Add drip file transformers

- for all three file functions on the drip contract

pkg/transformers/drip_file/config.go

@@ -0,0 +1,25 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package drip_file
+
+import "github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+
+var DripFileConfig = shared.TransformerConfig{
+	ContractAddress:     shared.DripContractAddress,
+	ContractAbi:         shared.DripABI,
+	Topics:              []string{shared.DripFileIlkSignature, shared.DripFileRepoSignature},
+	StartingBlockNumber: 0,
+	EndingBlockNumber:   100,
+}

pkg/transformers/drip_file/ilk/converter.go

@@ -0,0 +1,60 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk
+
+import (
+	"bytes"
+	"encoding/json"
+	"math/big"
+
+	"errors"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+)
+
+type Converter interface {
+	ToModel(ethLog types.Log) (DripFileIlkModel, error)
+}
+
+type DripFileIlkConverter struct{}
+
+func (DripFileIlkConverter) ToModel(ethLog types.Log) (DripFileIlkModel, error) {
+	err := verifyLog(ethLog)
+	if err != nil {
+		return DripFileIlkModel{}, err
+	}
+	ilk := string(bytes.Trim(ethLog.Topics[2].Bytes(), "\x00"))
+	vow := string(bytes.Trim(ethLog.Topics[3].Bytes(), "\x00"))
+	taxBytes := ethLog.Data[len(ethLog.Data)-shared.DataItemLength:]
+	tax := big.NewInt(0).SetBytes(taxBytes).String()
+	raw, err := json.Marshal(ethLog)
+	return DripFileIlkModel{
+		Ilk:              ilk,
+		Vow:              vow,
+		Tax:              tax,
+		TransactionIndex: ethLog.TxIndex,
+		Raw:              raw,
+	}, err
+}
+
+func verifyLog(log types.Log) error {
+	if len(log.Topics) < 4 {
+		return errors.New("log missing topics")
+	}
+	if len(log.Data) < shared.DataItemLength {
+		return errors.New("log missing data")
+	}
+	return nil
+}

pkg/transformers/drip_file/ilk/converter_test.go

@@ -0,0 +1,60 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk_test
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/ilk"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+)
+
+var _ = Describe("Drip file ilk converter", func() {
+	It("returns err if log missing topics", func() {
+		converter := ilk.DripFileIlkConverter{}
+		badLog := types.Log{
+			Topics: []common.Hash{{}},
+			Data:   []byte{1, 1, 1, 1, 1},
+		}
+
+		_, err := converter.ToModel(badLog)
+
+		Expect(err).To(HaveOccurred())
+	})
+
+	It("returns err if log missing data", func() {
+		converter := ilk.DripFileIlkConverter{}
+		badLog := types.Log{
+			Topics: []common.Hash{{}, {}, {}, {}},
+		}
+
+		_, err := converter.ToModel(badLog)
+
+		Expect(err).To(HaveOccurred())
+
+	})
+
+	It("converts a log to a model", func() {
+		converter := ilk.DripFileIlkConverter{}
+
+		model, err := converter.ToModel(test_data.EthDripFileIlkLog)
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(model).To(Equal(test_data.DripFileIlkModel))
+	})
+})

pkg/transformers/drip_file/ilk/ilk_suite_test.go

@@ -0,0 +1,27 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+func TestIlk(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Ilk Suite")
+}

pkg/transformers/drip_file/ilk/model.go

@@ -0,0 +1,23 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk
+
+type DripFileIlkModel struct {
+	Ilk              string
+	Vow              string
+	Tax              string
+	TransactionIndex uint   `db:"tx_idx"`
+	Raw              []byte `db:"raw_log"`
+}

pkg/transformers/drip_file/ilk/repository.go

@@ -0,0 +1,59 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk
+
+import (
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
+)
+
+type Repository interface {
+	Create(headerID int64, model DripFileIlkModel) error
+	MissingHeaders(startingBlockNumber, endingBlockNumber int64) ([]core.Header, error)
+}
+
+type DripFileIlkRepository struct {
+	db *postgres.DB
+}
+
+func NewDripFileIlkRepository(db *postgres.DB) DripFileIlkRepository {
+	return DripFileIlkRepository{db: db}
+}
+
+func (repository DripFileIlkRepository) Create(headerID int64, model DripFileIlkModel) error {
+	_, err := repository.db.Exec(
+		`INSERT into maker.drip_file_ilk (header_id, ilk, vow, tax, tx_idx, raw_log)
+        VALUES($1, $2, $3, $4::NUMERIC, $5, $6)`,
+		headerID, model.Ilk, model.Vow, model.Tax, model.TransactionIndex, model.Raw,
+	)
+	return err
+}
+
+func (repository DripFileIlkRepository) MissingHeaders(startingBlockNumber, endingBlockNumber int64) ([]core.Header, error) {
+	var result []core.Header
+	err := repository.db.Select(
+		&result,
+		`SELECT headers.id, headers.block_number FROM headers
+               LEFT JOIN maker.drip_file_ilk on headers.id = header_id
+               WHERE header_id ISNULL
+               AND headers.block_number >= $1
+               AND headers.block_number <= $2
+               AND headers.eth_node_fingerprint = $3`,
+		startingBlockNumber,
+		endingBlockNumber,
+		repository.db.Node.ID,
+	)
+	return result, err
+}

pkg/transformers/drip_file/ilk/repository_test.go

@@ -0,0 +1,145 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk_test
+
+import (
+	"database/sql"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres/repositories"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/ilk"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+	"github.com/vulcanize/vulcanizedb/test_config"
+)
+
+var _ = Describe("Drip file ilk repository", func() {
+	Describe("Create", func() {
+		It("adds a drip file ilk event", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileIlkRepository := ilk.NewDripFileIlkRepository(db)
+
+			err = dripFileIlkRepository.Create(headerID, test_data.DripFileIlkModel)
+
+			Expect(err).NotTo(HaveOccurred())
+			var dbDripFileIlk ilk.DripFileIlkModel
+			err = db.Get(&dbDripFileIlk, `SELECT ilk, vow, tax, tx_idx, raw_log FROM maker.drip_file_ilk WHERE header_id = $1`, headerID)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(dbDripFileIlk.Ilk).To(Equal(test_data.DripFileIlkModel.Ilk))
+			Expect(dbDripFileIlk.Vow).To(Equal(test_data.DripFileIlkModel.Vow))
+			Expect(dbDripFileIlk.Tax).To(Equal(test_data.DripFileIlkModel.Tax))
+			Expect(dbDripFileIlk.TransactionIndex).To(Equal(test_data.DripFileIlkModel.TransactionIndex))
+			Expect(dbDripFileIlk.Raw).To(MatchJSON(test_data.DripFileIlkModel.Raw))
+		})
+
+		It("does not duplicate drip file events", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileIlkRepository := ilk.NewDripFileIlkRepository(db)
+			err = dripFileIlkRepository.Create(headerID, test_data.DripFileIlkModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			err = dripFileIlkRepository.Create(headerID, test_data.DripFileIlkModel)
+
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("pq: duplicate key value violates unique constraint"))
+		})
+
+		It("removes drip file if corresponding header is deleted", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileIlkRepository := ilk.NewDripFileIlkRepository(db)
+			err = dripFileIlkRepository.Create(headerID, test_data.DripFileIlkModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			_, err = db.Exec(`DELETE FROM headers WHERE id = $1`, headerID)
+
+			Expect(err).NotTo(HaveOccurred())
+			var dbDripFileIlk ilk.DripFileIlkModel
+			err = db.Get(&dbDripFileIlk, `SELECT ilk, vow, tax, tx_idx, raw_log FROM maker.drip_file_ilk WHERE header_id = $1`, headerID)
+			Expect(err).To(HaveOccurred())
+			Expect(err).To(MatchError(sql.ErrNoRows))
+		})
+	})
+
+	Describe("MissingHeaders", func() {
+		It("returns headers with no associated drip file event", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			startingBlockNumber := int64(1)
+			dripFileIlkBlockNumber := int64(2)
+			endingBlockNumber := int64(3)
+			blockNumbers := []int64{startingBlockNumber, dripFileIlkBlockNumber, endingBlockNumber, endingBlockNumber + 1}
+			var headerIDs []int64
+			for _, n := range blockNumbers {
+				headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				headerIDs = append(headerIDs, headerID)
+				Expect(err).NotTo(HaveOccurred())
+			}
+			dripFileIlkRepository := ilk.NewDripFileIlkRepository(db)
+			err := dripFileIlkRepository.Create(headerIDs[1], test_data.DripFileIlkModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			headers, err := dripFileIlkRepository.MissingHeaders(startingBlockNumber, endingBlockNumber)
+
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(headers)).To(Equal(2))
+			Expect(headers[0].BlockNumber).To(Or(Equal(startingBlockNumber), Equal(endingBlockNumber)))
+			Expect(headers[1].BlockNumber).To(Or(Equal(startingBlockNumber), Equal(endingBlockNumber)))
+		})
+
+		It("only returns headers associated with the current node", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			blockNumbers := []int64{1, 2, 3}
+			headerRepository := repositories.NewHeaderRepository(db)
+			dbTwo := test_config.NewTestDB(core.Node{ID: "second"})
+			headerRepositoryTwo := repositories.NewHeaderRepository(dbTwo)
+			var headerIDs []int64
+			for _, n := range blockNumbers {
+				headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				Expect(err).NotTo(HaveOccurred())
+				headerIDs = append(headerIDs, headerID)
+				_, err = headerRepositoryTwo.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				Expect(err).NotTo(HaveOccurred())
+			}
+			dripFileIlkRepository := ilk.NewDripFileIlkRepository(db)
+			dripFileIlkRepositoryTwo := ilk.NewDripFileIlkRepository(dbTwo)
+			err := dripFileIlkRepository.Create(headerIDs[0], test_data.DripFileIlkModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			nodeOneMissingHeaders, err := dripFileIlkRepository.MissingHeaders(blockNumbers[0], blockNumbers[len(blockNumbers)-1])
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(nodeOneMissingHeaders)).To(Equal(len(blockNumbers) - 1))
+
+			nodeTwoMissingHeaders, err := dripFileIlkRepositoryTwo.MissingHeaders(blockNumbers[0], blockNumbers[len(blockNumbers)-1])
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(nodeTwoMissingHeaders)).To(Equal(len(blockNumbers)))
+		})
+	})
+})

pkg/transformers/drip_file/ilk/transformer.go

@@ -0,0 +1,71 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+)
+
+type DripFileIlkTransformer struct {
+	Config     shared.TransformerConfig
+	Converter  Converter
+	Fetcher    shared.LogFetcher
+	Repository Repository
+}
+
+type DripFileIlkTransformerInitializer struct {
+	Config shared.TransformerConfig
+}
+
+func (initializer DripFileIlkTransformerInitializer) NewDripFileIlkTransformer(db *postgres.DB, blockChain core.BlockChain) shared.Transformer {
+	converter := DripFileIlkConverter{}
+	fetcher := shared.NewFetcher(blockChain)
+	repository := NewDripFileIlkRepository(db)
+	return DripFileIlkTransformer{
+		Config:     initializer.Config,
+		Converter:  converter,
+		Fetcher:    fetcher,
+		Repository: repository,
+	}
+}
+
+func (transformer DripFileIlkTransformer) Execute() error {
+	missingHeaders, err := transformer.Repository.MissingHeaders(transformer.Config.StartingBlockNumber, transformer.Config.EndingBlockNumber)
+	if err != nil {
+		return err
+	}
+	for _, header := range missingHeaders {
+		topics := [][]common.Hash{{common.HexToHash(shared.DripFileIlkSignature)}}
+		matchingLogs, err := transformer.Fetcher.FetchLogs(drip_file.DripFileConfig.ContractAddress, topics, header.BlockNumber)
+		if err != nil {
+			return err
+		}
+		for _, log := range matchingLogs {
+			model, err := transformer.Converter.ToModel(log)
+			if err != nil {
+				return err
+			}
+			err = transformer.Repository.Create(header.Id, model)
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}

pkg/transformers/drip_file/ilk/transformer_test.go

@@ -0,0 +1,174 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ilk_test
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/fakes"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/ilk"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data/mocks"
+	ilk_mocks "github.com/vulcanize/vulcanizedb/pkg/transformers/test_data/mocks/drip_file/ilk"
+)
+
+var _ = Describe("Drip file ilk transformer", func() {
+	It("gets missing headers for block numbers specified in config", func() {
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		transformer := ilk.DripFileIlkTransformer{
+			Config:     drip_file.DripFileConfig,
+			Fetcher:    &mocks.MockLogFetcher{},
+			Converter:  &ilk_mocks.MockDripFileIlkConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(repository.PassedStartingBlockNumber).To(Equal(drip_file.DripFileConfig.StartingBlockNumber))
+		Expect(repository.PassedEndingBlockNumber).To(Equal(drip_file.DripFileConfig.EndingBlockNumber))
+	})
+
+	It("returns error if repository returns error for missing headers", func() {
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		repository.SetMissingHeadersErr(fakes.FakeError)
+		transformer := ilk.DripFileIlkTransformer{
+			Fetcher:    &mocks.MockLogFetcher{},
+			Converter:  &ilk_mocks.MockDripFileIlkConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("fetches logs for missing headers", func() {
+		fetcher := &mocks.MockLogFetcher{}
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}, {BlockNumber: 2}})
+		transformer := ilk.DripFileIlkTransformer{
+			Fetcher:    fetcher,
+			Converter:  &ilk_mocks.MockDripFileIlkConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(fetcher.FetchedBlocks).To(Equal([]int64{1, 2}))
+		Expect(fetcher.FetchedContractAddress).To(Equal(drip_file.DripFileConfig.ContractAddress))
+		Expect(fetcher.FetchedTopics).To(Equal([][]common.Hash{{common.HexToHash(shared.DripFileIlkSignature)}}))
+	})
+
+	It("returns error if fetcher returns error", func() {
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetcherError(fakes.FakeError)
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := ilk.DripFileIlkTransformer{
+			Fetcher:    fetcher,
+			Converter:  &ilk_mocks.MockDripFileIlkConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("converts matching logs", func() {
+		converter := &ilk_mocks.MockDripFileIlkConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileIlkLog})
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := ilk.DripFileIlkTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(converter.PassedLog).To(Equal(test_data.EthDripFileIlkLog))
+	})
+
+	It("returns error if converter returns error", func() {
+		converter := &ilk_mocks.MockDripFileIlkConverter{}
+		converter.SetConverterError(fakes.FakeError)
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileIlkLog})
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := ilk.DripFileIlkTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("persists drip file model", func() {
+		converter := &ilk_mocks.MockDripFileIlkConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileIlkLog})
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		fakeHeader := core.Header{BlockNumber: 1, Id: 2}
+		repository.SetMissingHeaders([]core.Header{fakeHeader})
+		transformer := ilk.DripFileIlkTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(repository.PassedHeaderID).To(Equal(fakeHeader.Id))
+		Expect(repository.PassedModel).To(Equal(test_data.DripFileIlkModel))
+	})
+
+	It("returns error if repository returns error for create", func() {
+		converter := &ilk_mocks.MockDripFileIlkConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileIlkLog})
+		repository := &ilk_mocks.MockDripFileIlkRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1, Id: 2}})
+		repository.SetCreateError(fakes.FakeError)
+		transformer := ilk.DripFileIlkTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+})

pkg/transformers/drip_file/repo/converter.go

@@ -0,0 +1,52 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"github.com/ethereum/go-ethereum/core/types"
+	"math/big"
+)
+
+type Converter interface {
+	ToModel(ethLog types.Log) (DripFileRepoModel, error)
+}
+
+type DripFileRepoConverter struct{}
+
+func (DripFileRepoConverter) ToModel(ethLog types.Log) (DripFileRepoModel, error) {
+	err := verifyLog(ethLog)
+	if err != nil {
+		return DripFileRepoModel{}, err
+	}
+	what := string(bytes.Trim(ethLog.Topics[2].Bytes(), "\x00"))
+	data := big.NewInt(0).SetBytes(ethLog.Topics[3].Bytes()).String()
+	raw, err := json.Marshal(ethLog)
+	return DripFileRepoModel{
+		What:             what,
+		Data:             data,
+		TransactionIndex: ethLog.TxIndex,
+		Raw:              raw,
+	}, err
+}
+
+func verifyLog(log types.Log) error {
+	if len(log.Topics) < 4 {
+		return errors.New("log missing topics")
+	}
+	return nil
+}

pkg/transformers/drip_file/repo/converter_test.go

@@ -0,0 +1,48 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo_test
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/repo"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+)
+
+var _ = Describe("Drip file repo converter", func() {
+	It("returns err if log missing topics", func() {
+		converter := repo.DripFileRepoConverter{}
+		badLog := types.Log{
+			Topics: []common.Hash{{}},
+			Data:   []byte{1, 1, 1, 1, 1},
+		}
+
+		_, err := converter.ToModel(badLog)
+
+		Expect(err).To(HaveOccurred())
+	})
+
+	It("converts a log to a model", func() {
+		converter := repo.DripFileRepoConverter{}
+
+		model, err := converter.ToModel(test_data.EthDripFileRepoLog)
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(model).To(Equal(test_data.DripFileRepoModel))
+	})
+})

pkg/transformers/drip_file/repo/model.go

@@ -0,0 +1,22 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo
+
+type DripFileRepoModel struct {
+	What             string
+	Data             string
+	TransactionIndex uint   `db:"tx_idx"`
+	Raw              []byte `db:"raw_log"`
+}

pkg/transformers/drip_file/repo/repo_suite_test.go

@@ -0,0 +1,27 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+func TestRepo(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Repo Suite")
+}

pkg/transformers/drip_file/repo/repository.go

@@ -0,0 +1,59 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo
+
+import (
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
+)
+
+type Repository interface {
+	Create(headerID int64, model DripFileRepoModel) error
+	MissingHeaders(startingBlockNumber, endingBlockNumber int64) ([]core.Header, error)
+}
+
+type DripFileRepoRepository struct {
+	db *postgres.DB
+}
+
+func NewDripFileRepoRepository(db *postgres.DB) DripFileRepoRepository {
+	return DripFileRepoRepository{db: db}
+}
+
+func (repository DripFileRepoRepository) Create(headerID int64, model DripFileRepoModel) error {
+	_, err := repository.db.Exec(
+		`INSERT into maker.drip_file_repo (header_id, what, data, tx_idx, raw_log)
+        VALUES($1, $2, $3::NUMERIC, $4, $5)`,
+		headerID, model.What, model.Data, model.TransactionIndex, model.Raw,
+	)
+	return err
+}
+
+func (repository DripFileRepoRepository) MissingHeaders(startingBlockNumber, endingBlockNumber int64) ([]core.Header, error) {
+	var result []core.Header
+	err := repository.db.Select(
+		&result,
+		`SELECT headers.id, headers.block_number FROM headers
+               LEFT JOIN maker.drip_file_repo on headers.id = header_id
+               WHERE header_id ISNULL
+               AND headers.block_number >= $1
+               AND headers.block_number <= $2
+               AND headers.eth_node_fingerprint = $3`,
+		startingBlockNumber,
+		endingBlockNumber,
+		repository.db.Node.ID,
+	)
+	return result, err
+}

pkg/transformers/drip_file/repo/repository_test.go

@@ -0,0 +1,142 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo_test
+
+import (
+	"database/sql"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres/repositories"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/repo"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+	"github.com/vulcanize/vulcanizedb/test_config"
+)
+
+var _ = Describe("", func() {
+	Describe("Create", func() {
+		It("adds a drip file repo event", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileRepoRepository := repo.NewDripFileRepoRepository(db)
+
+			err = dripFileRepoRepository.Create(headerID, test_data.DripFileRepoModel)
+
+			Expect(err).NotTo(HaveOccurred())
+			var dbDripFileRepo repo.DripFileRepoModel
+			err = db.Get(&dbDripFileRepo, `SELECT what, data, tx_idx, raw_log FROM maker.drip_file_repo WHERE header_id = $1`, headerID)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(dbDripFileRepo.What).To(Equal(test_data.DripFileRepoModel.What))
+			Expect(dbDripFileRepo.Data).To(Equal(test_data.DripFileRepoModel.Data))
+			Expect(dbDripFileRepo.TransactionIndex).To(Equal(test_data.DripFileRepoModel.TransactionIndex))
+			Expect(dbDripFileRepo.Raw).To(MatchJSON(test_data.DripFileRepoModel.Raw))
+		})
+
+		It("does not duplicate drip file events", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileRepoRepository := repo.NewDripFileRepoRepository(db)
+			err = dripFileRepoRepository.Create(headerID, test_data.DripFileRepoModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			err = dripFileRepoRepository.Create(headerID, test_data.DripFileRepoModel)
+
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("pq: duplicate key value violates unique constraint"))
+		})
+
+		It("removes drip file if corresponding header is deleted", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileRepoRepository := repo.NewDripFileRepoRepository(db)
+			err = dripFileRepoRepository.Create(headerID, test_data.DripFileRepoModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			_, err = db.Exec(`DELETE FROM headers WHERE id = $1`, headerID)
+
+			Expect(err).NotTo(HaveOccurred())
+			var dbDripFileRepo repo.DripFileRepoModel
+			err = db.Get(&dbDripFileRepo, `SELECT what, data, tx_idx, raw_log FROM maker.drip_file_repo WHERE header_id = $1`, headerID)
+			Expect(err).To(HaveOccurred())
+			Expect(err).To(MatchError(sql.ErrNoRows))
+		})
+	})
+
+	Describe("MissingHeaders", func() {
+		It("returns headers with no associated drip file event", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			startingBlockNumber := int64(1)
+			dripFileRepoBlockNumber := int64(2)
+			endingBlockNumber := int64(3)
+			blockNumbers := []int64{startingBlockNumber, dripFileRepoBlockNumber, endingBlockNumber, endingBlockNumber + 1}
+			var headerIDs []int64
+			for _, n := range blockNumbers {
+				headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				headerIDs = append(headerIDs, headerID)
+				Expect(err).NotTo(HaveOccurred())
+			}
+			dripFileRepoRepository := repo.NewDripFileRepoRepository(db)
+			err := dripFileRepoRepository.Create(headerIDs[1], test_data.DripFileRepoModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			headers, err := dripFileRepoRepository.MissingHeaders(startingBlockNumber, endingBlockNumber)
+
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(headers)).To(Equal(2))
+			Expect(headers[0].BlockNumber).To(Or(Equal(startingBlockNumber), Equal(endingBlockNumber)))
+			Expect(headers[1].BlockNumber).To(Or(Equal(startingBlockNumber), Equal(endingBlockNumber)))
+		})
+
+		It("only returns headers associated with the current node", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			blockNumbers := []int64{1, 2, 3}
+			headerRepository := repositories.NewHeaderRepository(db)
+			dbTwo := test_config.NewTestDB(core.Node{ID: "second"})
+			headerRepositoryTwo := repositories.NewHeaderRepository(dbTwo)
+			var headerIDs []int64
+			for _, n := range blockNumbers {
+				headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				Expect(err).NotTo(HaveOccurred())
+				headerIDs = append(headerIDs, headerID)
+				_, err = headerRepositoryTwo.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				Expect(err).NotTo(HaveOccurred())
+			}
+			dripFileRepoRepository := repo.NewDripFileRepoRepository(db)
+			dripFileRepoRepositoryTwo := repo.NewDripFileRepoRepository(dbTwo)
+			err := dripFileRepoRepository.Create(headerIDs[0], test_data.DripFileRepoModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			nodeOneMissingHeaders, err := dripFileRepoRepository.MissingHeaders(blockNumbers[0], blockNumbers[len(blockNumbers)-1])
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(nodeOneMissingHeaders)).To(Equal(len(blockNumbers) - 1))
+
+			nodeTwoMissingHeaders, err := dripFileRepoRepositoryTwo.MissingHeaders(blockNumbers[0], blockNumbers[len(blockNumbers)-1])
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(nodeTwoMissingHeaders)).To(Equal(len(blockNumbers)))
+		})
+	})
+})

pkg/transformers/drip_file/repo/transformer.go

@@ -0,0 +1,71 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+)
+
+type DripFileRepoTransformer struct {
+	Config     shared.TransformerConfig
+	Converter  Converter
+	Fetcher    shared.LogFetcher
+	Repository Repository
+}
+
+type DripFileRepoTransformerInitializer struct {
+	Config shared.TransformerConfig
+}
+
+func (initializer DripFileRepoTransformerInitializer) NewDripFileRepoTransformer(db *postgres.DB, blockChain core.BlockChain) shared.Transformer {
+	converter := DripFileRepoConverter{}
+	fetcher := shared.NewFetcher(blockChain)
+	repository := NewDripFileRepoRepository(db)
+	return DripFileRepoTransformer{
+		Config:     initializer.Config,
+		Converter:  converter,
+		Fetcher:    fetcher,
+		Repository: repository,
+	}
+}
+
+func (transformer DripFileRepoTransformer) Execute() error {
+	missingHeaders, err := transformer.Repository.MissingHeaders(transformer.Config.StartingBlockNumber, transformer.Config.EndingBlockNumber)
+	if err != nil {
+		return err
+	}
+	for _, header := range missingHeaders {
+		topics := [][]common.Hash{{common.HexToHash(shared.DripFileRepoSignature)}}
+		matchingLogs, err := transformer.Fetcher.FetchLogs(drip_file.DripFileConfig.ContractAddress, topics, header.BlockNumber)
+		if err != nil {
+			return err
+		}
+		for _, log := range matchingLogs {
+			model, err := transformer.Converter.ToModel(log)
+			if err != nil {
+				return err
+			}
+			err = transformer.Repository.Create(header.Id, model)
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}

pkg/transformers/drip_file/repo/transformer_test.go

@@ -0,0 +1,175 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package repo_test
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/fakes"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/repo"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data/mocks"
+	repo_mocks "github.com/vulcanize/vulcanizedb/pkg/transformers/test_data/mocks/drip_file/repo"
+)
+
+var _ = Describe("Drip file repo transformer", func() {
+	It("gets missing headers for block numbers specified in config", func() {
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		transformer := repo.DripFileRepoTransformer{
+			Config:     drip_file.DripFileConfig,
+			Fetcher:    &mocks.MockLogFetcher{},
+			Converter:  &repo_mocks.MockDripFileRepoConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(repository.PassedStartingBlockNumber).To(Equal(drip_file.DripFileConfig.StartingBlockNumber))
+		Expect(repository.PassedEndingBlockNumber).To(Equal(drip_file.DripFileConfig.EndingBlockNumber))
+	})
+
+	It("returns error if repository returns error for missing headers", func() {
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		repository.SetMissingHeadersErr(fakes.FakeError)
+		transformer := repo.DripFileRepoTransformer{
+			Fetcher:    &mocks.MockLogFetcher{},
+			Converter:  &repo_mocks.MockDripFileRepoConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("fetches logs for missing headers", func() {
+		fetcher := &mocks.MockLogFetcher{}
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}, {BlockNumber: 2}})
+		transformer := repo.DripFileRepoTransformer{
+			Fetcher:    fetcher,
+			Converter:  &repo_mocks.MockDripFileRepoConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(fetcher.FetchedBlocks).To(Equal([]int64{1, 2}))
+		Expect(fetcher.FetchedContractAddress).To(Equal(drip_file.DripFileConfig.ContractAddress))
+		Expect(fetcher.FetchedTopics).To(Equal([][]common.Hash{{common.HexToHash(shared.DripFileRepoSignature)}}))
+	})
+
+	It("returns error if fetcher returns error", func() {
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetcherError(fakes.FakeError)
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := repo.DripFileRepoTransformer{
+			Fetcher:    fetcher,
+			Converter:  &repo_mocks.MockDripFileRepoConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("converts matching logs", func() {
+		converter := &repo_mocks.MockDripFileRepoConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileRepoLog})
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := repo.DripFileRepoTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(converter.PassedLog).To(Equal(test_data.EthDripFileRepoLog))
+	})
+
+	It("returns error if converter returns error", func() {
+		converter := &repo_mocks.MockDripFileRepoConverter{}
+		converter.SetConverterError(fakes.FakeError)
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileRepoLog})
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := repo.DripFileRepoTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("persists drip file model", func() {
+		converter := &repo_mocks.MockDripFileRepoConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileRepoLog})
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		fakeHeader := core.Header{BlockNumber: 1, Id: 2}
+		repository.SetMissingHeaders([]core.Header{fakeHeader})
+		transformer := repo.DripFileRepoTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(repository.PassedHeaderID).To(Equal(fakeHeader.Id))
+		Expect(repository.PassedModel).To(Equal(test_data.DripFileRepoModel))
+	})
+
+	It("returns error if repository returns error for create", func() {
+		converter := &repo_mocks.MockDripFileRepoConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileRepoLog})
+		repository := &repo_mocks.MockDripFileRepoRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1, Id: 2}})
+		repository.SetCreateError(fakes.FakeError)
+		transformer := repo.DripFileRepoTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+})

pkg/transformers/drip_file/vow/converter.go

@@ -0,0 +1,51 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"github.com/ethereum/go-ethereum/core/types"
+)
+
+type Converter interface {
+	ToModel(ethLog types.Log) (DripFileVowModel, error)
+}
+
+type DripFileVowConverter struct{}
+
+func (DripFileVowConverter) ToModel(ethLog types.Log) (DripFileVowModel, error) {
+	err := verifyLog(ethLog)
+	if err != nil {
+		return DripFileVowModel{}, err
+	}
+	what := string(bytes.Trim(ethLog.Topics[2].Bytes(), "\x00"))
+	data := string(bytes.Trim(ethLog.Topics[3].Bytes(), "\x00"))
+	raw, err := json.Marshal(ethLog)
+	return DripFileVowModel{
+		What:             what,
+		Data:             data,
+		TransactionIndex: ethLog.TxIndex,
+		Raw:              raw,
+	}, err
+}
+
+func verifyLog(log types.Log) error {
+	if len(log.Topics) < 4 {
+		return errors.New("log missing topics")
+	}
+	return nil
+}

pkg/transformers/drip_file/vow/converter_test.go

@@ -0,0 +1,48 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow_test
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/vow"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+)
+
+var _ = Describe("Drip file repo converter", func() {
+	It("returns err if log missing topics", func() {
+		converter := vow.DripFileVowConverter{}
+		badLog := types.Log{
+			Topics: []common.Hash{{}},
+			Data:   []byte{1, 1, 1, 1, 1},
+		}
+
+		_, err := converter.ToModel(badLog)
+
+		Expect(err).To(HaveOccurred())
+	})
+
+	It("converts a log to a model", func() {
+		converter := vow.DripFileVowConverter{}
+
+		model, err := converter.ToModel(test_data.EthDripFileVowLog)
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(model).To(Equal(test_data.DripFileVowModel))
+	})
+})

pkg/transformers/drip_file/vow/model.go

@@ -0,0 +1,22 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow
+
+type DripFileVowModel struct {
+	What             string
+	Data             string
+	TransactionIndex uint   `db:"tx_idx"`
+	Raw              []byte `db:"raw_log"`
+}

pkg/transformers/drip_file/vow/repository.go

@@ -0,0 +1,59 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow
+
+import (
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
+)
+
+type Repository interface {
+	Create(headerID int64, model DripFileVowModel) error
+	MissingHeaders(startingBlockNumber, endingBlockNumber int64) ([]core.Header, error)
+}
+
+type DripFileVowRepository struct {
+	db *postgres.DB
+}
+
+func NewDripFileVowRepository(db *postgres.DB) DripFileVowRepository {
+	return DripFileVowRepository{db: db}
+}
+
+func (repository DripFileVowRepository) Create(headerID int64, model DripFileVowModel) error {
+	_, err := repository.db.Exec(
+		`INSERT into maker.drip_file_vow (header_id, what, data, tx_idx, raw_log)
+        VALUES($1, $2, $3, $4, $5)`,
+		headerID, model.What, model.Data, model.TransactionIndex, model.Raw,
+	)
+	return err
+}
+
+func (repository DripFileVowRepository) MissingHeaders(startingBlockNumber, endingBlockNumber int64) ([]core.Header, error) {
+	var result []core.Header
+	err := repository.db.Select(
+		&result,
+		`SELECT headers.id, headers.block_number FROM headers
+               LEFT JOIN maker.drip_file_vow on headers.id = header_id
+               WHERE header_id ISNULL
+               AND headers.block_number >= $1
+               AND headers.block_number <= $2
+               AND headers.eth_node_fingerprint = $3`,
+		startingBlockNumber,
+		endingBlockNumber,
+		repository.db.Node.ID,
+	)
+	return result, err
+}

pkg/transformers/drip_file/vow/repository_test.go

@@ -0,0 +1,142 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow_test
+
+import (
+	"database/sql"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres/repositories"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/vow"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+	"github.com/vulcanize/vulcanizedb/test_config"
+)
+
+var _ = Describe("", func() {
+	Describe("Create", func() {
+		It("adds a drip file vow event", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileVowRepository := vow.NewDripFileVowRepository(db)
+
+			err = dripFileVowRepository.Create(headerID, test_data.DripFileVowModel)
+
+			Expect(err).NotTo(HaveOccurred())
+			var dbDripFileVow vow.DripFileVowModel
+			err = db.Get(&dbDripFileVow, `SELECT what, data, tx_idx, raw_log FROM maker.drip_file_vow WHERE header_id = $1`, headerID)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(dbDripFileVow.What).To(Equal(test_data.DripFileVowModel.What))
+			Expect(dbDripFileVow.Data).To(Equal(test_data.DripFileVowModel.Data))
+			Expect(dbDripFileVow.TransactionIndex).To(Equal(test_data.DripFileVowModel.TransactionIndex))
+			Expect(dbDripFileVow.Raw).To(MatchJSON(test_data.DripFileVowModel.Raw))
+		})
+
+		It("does not duplicate drip file events", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileVowRepository := vow.NewDripFileVowRepository(db)
+			err = dripFileVowRepository.Create(headerID, test_data.DripFileVowModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			err = dripFileVowRepository.Create(headerID, test_data.DripFileVowModel)
+
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("pq: duplicate key value violates unique constraint"))
+		})
+
+		It("removes drip file if corresponding header is deleted", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{})
+			Expect(err).NotTo(HaveOccurred())
+			dripFileVowRepository := vow.NewDripFileVowRepository(db)
+			err = dripFileVowRepository.Create(headerID, test_data.DripFileVowModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			_, err = db.Exec(`DELETE FROM headers WHERE id = $1`, headerID)
+
+			Expect(err).NotTo(HaveOccurred())
+			var dbDripFileVow vow.DripFileVowModel
+			err = db.Get(&dbDripFileVow, `SELECT what, data, tx_idx, raw_log FROM maker.drip_file_vow WHERE header_id = $1`, headerID)
+			Expect(err).To(HaveOccurred())
+			Expect(err).To(MatchError(sql.ErrNoRows))
+		})
+	})
+
+	Describe("MissingHeaders", func() {
+		It("returns headers with no associated drip file event", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			headerRepository := repositories.NewHeaderRepository(db)
+			startingBlockNumber := int64(1)
+			dripFileVowBlockNumber := int64(2)
+			endingBlockNumber := int64(3)
+			blockNumbers := []int64{startingBlockNumber, dripFileVowBlockNumber, endingBlockNumber, endingBlockNumber + 1}
+			var headerIDs []int64
+			for _, n := range blockNumbers {
+				headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				headerIDs = append(headerIDs, headerID)
+				Expect(err).NotTo(HaveOccurred())
+			}
+			dripFileVowRepository := vow.NewDripFileVowRepository(db)
+			err := dripFileVowRepository.Create(headerIDs[1], test_data.DripFileVowModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			headers, err := dripFileVowRepository.MissingHeaders(startingBlockNumber, endingBlockNumber)
+
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(headers)).To(Equal(2))
+			Expect(headers[0].BlockNumber).To(Or(Equal(startingBlockNumber), Equal(endingBlockNumber)))
+			Expect(headers[1].BlockNumber).To(Or(Equal(startingBlockNumber), Equal(endingBlockNumber)))
+		})
+
+		It("only returns headers associated with the current node", func() {
+			db := test_config.NewTestDB(core.Node{})
+			test_config.CleanTestDB(db)
+			blockNumbers := []int64{1, 2, 3}
+			headerRepository := repositories.NewHeaderRepository(db)
+			dbTwo := test_config.NewTestDB(core.Node{ID: "second"})
+			headerRepositoryTwo := repositories.NewHeaderRepository(dbTwo)
+			var headerIDs []int64
+			for _, n := range blockNumbers {
+				headerID, err := headerRepository.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				Expect(err).NotTo(HaveOccurred())
+				headerIDs = append(headerIDs, headerID)
+				_, err = headerRepositoryTwo.CreateOrUpdateHeader(core.Header{BlockNumber: n})
+				Expect(err).NotTo(HaveOccurred())
+			}
+			dripFileVowRepository := vow.NewDripFileVowRepository(db)
+			dripFileVowRepositoryTwo := vow.NewDripFileVowRepository(dbTwo)
+			err := dripFileVowRepository.Create(headerIDs[0], test_data.DripFileVowModel)
+			Expect(err).NotTo(HaveOccurred())
+
+			nodeOneMissingHeaders, err := dripFileVowRepository.MissingHeaders(blockNumbers[0], blockNumbers[len(blockNumbers)-1])
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(nodeOneMissingHeaders)).To(Equal(len(blockNumbers) - 1))
+
+			nodeTwoMissingHeaders, err := dripFileVowRepositoryTwo.MissingHeaders(blockNumbers[0], blockNumbers[len(blockNumbers)-1])
+			Expect(err).NotTo(HaveOccurred())
+			Expect(len(nodeTwoMissingHeaders)).To(Equal(len(blockNumbers)))
+		})
+	})
+})

pkg/transformers/drip_file/vow/transformer.go

@@ -0,0 +1,53 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+)
+
+type DripFileVowTransformer struct {
+	Config     shared.TransformerConfig
+	Converter  Converter
+	Fetcher    shared.LogFetcher
+	Repository Repository
+}
+
+func (transformer DripFileVowTransformer) Execute() error {
+	missingHeaders, err := transformer.Repository.MissingHeaders(transformer.Config.StartingBlockNumber, transformer.Config.EndingBlockNumber)
+	if err != nil {
+		return err
+	}
+	for _, header := range missingHeaders {
+		topics := [][]common.Hash{{common.HexToHash(shared.DripFileVowSignature)}}
+		matchingLogs, err := transformer.Fetcher.FetchLogs(drip_file.DripFileConfig.ContractAddress, topics, header.BlockNumber)
+		if err != nil {
+			return err
+		}
+		for _, log := range matchingLogs {
+			model, err := transformer.Converter.ToModel(log)
+			if err != nil {
+				return err
+			}
+			err = transformer.Repository.Create(header.Id, model)
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}

pkg/transformers/drip_file/vow/transformer_test.go

@@ -0,0 +1,175 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow_test
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/fakes"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/drip_file/vow"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/test_data/mocks"
+	vow_mocks "github.com/vulcanize/vulcanizedb/pkg/transformers/test_data/mocks/drip_file/vow"
+)
+
+var _ = Describe("Drip file vow transformer", func() {
+	It("gets missing headers for block numbers specified in config", func() {
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		transformer := vow.DripFileVowTransformer{
+			Config:     drip_file.DripFileConfig,
+			Fetcher:    &mocks.MockLogFetcher{},
+			Converter:  &vow_mocks.MockDripFileVowConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(repository.PassedStartingBlockNumber).To(Equal(drip_file.DripFileConfig.StartingBlockNumber))
+		Expect(repository.PassedEndingBlockNumber).To(Equal(drip_file.DripFileConfig.EndingBlockNumber))
+	})
+
+	It("returns error if repository returns error for missing headers", func() {
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		repository.SetMissingHeadersErr(fakes.FakeError)
+		transformer := vow.DripFileVowTransformer{
+			Fetcher:    &mocks.MockLogFetcher{},
+			Converter:  &vow_mocks.MockDripFileVowConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("fetches logs for missing headers", func() {
+		fetcher := &mocks.MockLogFetcher{}
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}, {BlockNumber: 2}})
+		transformer := vow.DripFileVowTransformer{
+			Fetcher:    fetcher,
+			Converter:  &vow_mocks.MockDripFileVowConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(fetcher.FetchedBlocks).To(Equal([]int64{1, 2}))
+		Expect(fetcher.FetchedContractAddress).To(Equal(drip_file.DripFileConfig.ContractAddress))
+		Expect(fetcher.FetchedTopics).To(Equal([][]common.Hash{{common.HexToHash(shared.DripFileVowSignature)}}))
+	})
+
+	It("returns error if fetcher returns error", func() {
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetcherError(fakes.FakeError)
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := vow.DripFileVowTransformer{
+			Fetcher:    fetcher,
+			Converter:  &vow_mocks.MockDripFileVowConverter{},
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("converts matching logs", func() {
+		converter := &vow_mocks.MockDripFileVowConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileVowLog})
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := vow.DripFileVowTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(converter.PassedLog).To(Equal(test_data.EthDripFileVowLog))
+	})
+
+	It("returns error if converter returns error", func() {
+		converter := &vow_mocks.MockDripFileVowConverter{}
+		converter.SetConverterError(fakes.FakeError)
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileVowLog})
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1}})
+		transformer := vow.DripFileVowTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+
+	It("persists drip file model", func() {
+		converter := &vow_mocks.MockDripFileVowConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileVowLog})
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		fakeHeader := core.Header{BlockNumber: 1, Id: 2}
+		repository.SetMissingHeaders([]core.Header{fakeHeader})
+		transformer := vow.DripFileVowTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(repository.PassedHeaderID).To(Equal(fakeHeader.Id))
+		Expect(repository.PassedModel).To(Equal(test_data.DripFileVowModel))
+	})
+
+	It("returns error if repository returns error for create", func() {
+		converter := &vow_mocks.MockDripFileVowConverter{}
+		fetcher := &mocks.MockLogFetcher{}
+		fetcher.SetFetchedLogs([]types.Log{test_data.EthDripFileVowLog})
+		repository := &vow_mocks.MockDripFileVowRepository{}
+		repository.SetMissingHeaders([]core.Header{{BlockNumber: 1, Id: 2}})
+		repository.SetCreateError(fakes.FakeError)
+		transformer := vow.DripFileVowTransformer{
+			Fetcher:    fetcher,
+			Converter:  converter,
+			Repository: repository,
+		}
+
+		err := transformer.Execute()
+
+		Expect(err).To(HaveOccurred())
+		Expect(err).To(MatchError(fakes.FakeError))
+	})
+})

pkg/transformers/drip_file/vow/vow_suite_test.go

@@ -0,0 +1,27 @@
+// Copyright 2018 Vulcanize
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vow_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+func TestVow(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Vow Suite")
+}