refactoring plugin generating code

2019-02-24 21:38:47 -06:00
parent decc2a3caf
commit a322372713
16 changed files with 549 additions and 361 deletions
@@ -0,0 +1,118 @@
+// VulcanizeDB
+// Copyright © 2018 Vulcanize
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package builder
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"github.com/vulcanize/vulcanizedb/pkg/config"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/helpers"
+)
+
+type PluginBuilder interface {
+	BuildPlugin() error
+	CleanUp() error
+}
+
+type builder struct {
+	GenConfig  config.Plugin
+	tmpVenDirs []string
+	goFile     string
+}
+
+func NewPluginBuilder(gc config.Plugin, dbc config.Database) *builder {
+	return &builder{
+		GenConfig:  gc,
+		tmpVenDirs: make([]string, 0, len(gc.Dependencies)),
+	}
+}
+
+func (b *builder) BuildPlugin() error {
+	// Get plugin .go and .so file paths
+	var err error
+	var soFile string
+	b.goFile, soFile, err = b.GenConfig.GetPluginPaths()
+	if err != nil {
+		return err
+	}
+
+	// setup env to build plugin
+	err = b.setupBuildEnv()
+	if err != nil {
+		return err
+	}
+
+	// Build the .go file into a .so plugin
+	err = exec.Command("go", "build", "-buildmode=plugin", "-o", soFile, b.goFile).Run()
+	if err != nil {
+		return errors.New(fmt.Sprintf("unable to build .so file: %s", err.Error()))
+	}
+	return nil
+}
+
+// Sets up temporary vendor libs needed for plugin build
+func (b *builder) setupBuildEnv() error {
+	// TODO: Less hacky way of handling plugin build deps
+	vendorPath, err := helpers.CleanPath("$GOPATH/src/github.com/vulcanize/vulcanizedb/vendor")
+	if err != nil {
+		return err
+	}
+
+	// Import transformer dependencies so that we can build our plugin
+	for name, importPath := range b.GenConfig.Dependencies {
+		index := strings.Index(importPath, "/")
+		gitPath := importPath[:index] + ":" + importPath[index+1:]
+		importURL := "git@" + gitPath + ".git"
+		depPath := filepath.Join(vendorPath, importPath)
+		err = exec.Command("git", "clone", importURL, depPath).Run()
+		if err != nil {
+			return errors.New(fmt.Sprintf("unable to clone %s transformer dependency: %s", name, err.Error()))
+		}
+
+		err := os.RemoveAll(filepath.Join(depPath, "vendor/"))
+		if err != nil {
+			return err
+		}
+
+		b.tmpVenDirs = append(b.tmpVenDirs, depPath)
+	}
+
+	return nil
+}
+
+func (b *builder) CleanUp() error {
+	if !b.GenConfig.Save {
+		err := helpers.ClearFiles(b.goFile)
+		if err != nil {
+			return err
+		}
+	}
+
+	for _, venDir := range b.tmpVenDirs {
+		err := os.RemoveAll(venDir)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
@@ -0,0 +1,69 @@
+// VulcanizeDB
+// Copyright © 2018 Vulcanize
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package plugin
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/vulcanize/vulcanizedb/pkg/config"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/builder"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/manager"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/writer"
+)
+
+type Generator interface {
+	GenerateExporterPlugin() error
+}
+
+type generator struct {
+	writer.PluginWriter
+	builder.PluginBuilder
+	manager.MigrationManager
+}
+
+func NewGenerator(gc config.Plugin, dbc config.Database) (*generator, error) {
+	if len(gc.Initializers) < 1 {
+		return nil, errors.New("generator needs to be configured with TransformerInitializer import paths")
+	}
+	if len(gc.Dependencies) < 1 {
+		return nil, errors.New("generator needs to be configured with root repository path(s)")
+	}
+	if len(gc.Migrations) < 1 {
+		fmt.Fprintf(os.Stderr, "warning: no db migration paths have been provided for the plugin transformers\r\n")
+	}
+	return &generator{
+		PluginWriter:     writer.NewPluginWriter(gc),
+		PluginBuilder:    builder.NewPluginBuilder(gc, dbc),
+		MigrationManager: manager.NewMigrationManager(gc, dbc),
+	}, nil
+}
+
+func (g *generator) GenerateExporterPlugin() error {
+	err := g.PluginWriter.WritePlugin()
+	if err != nil {
+		return err
+	}
+	defer g.PluginBuilder.CleanUp()
+	err = g.PluginBuilder.BuildPlugin()
+	if err != nil {
+		return err
+	}
+
+	return g.MigrationManager.RunMigrations()
+}
@@ -0,0 +1,35 @@
+// VulcanizeDB
+// Copyright © 2018 Vulcanize
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package plugin_test
+
+import (
+	"io/ioutil"
+	"log"
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+func TestRepository(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Gen Suite Test")
+}
+
+var _ = BeforeSuite(func() {
+	log.SetOutput(ioutil.Discard)
+})
@@ -0,0 +1,151 @@
+// VulcanizeDB
+// Copyright © 2018 Vulcanize
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package plugin_test
+
+import (
+	"plugin"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/spf13/viper"
+
+	"github.com/vulcanize/vulcanizedb/libraries/shared/transformer"
+	"github.com/vulcanize/vulcanizedb/libraries/shared/watcher"
+	"github.com/vulcanize/vulcanizedb/pkg/config"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres/repositories"
+	p2 "github.com/vulcanize/vulcanizedb/pkg/plugin"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/helpers"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/test_helpers"
+)
+
+var genConfig = config.Plugin{
+	Initializers: map[string]string{
+		"bite": "github.com/vulcanize/mcd_transformers/transformers/bite/initializer",
+		"deal": "github.com/vulcanize/mcd_transformers/transformers/deal/initializer",
+	},
+	Dependencies: map[string]string{
+		"mcd_transformers": "github.com/vulcanize/mcd_transformers",
+	},
+	//Migrations: map[string]string{"mcd_transformers" : "db/migrations"},
+	FileName: "externalTestTransformerSet",
+	FilePath: "$GOPATH/src/github.com/vulcanize/vulcanizedb/pkg/plugin/test_helpers/test",
+	Save:     false,
+}
+
+var dbConfig = config.Database{
+	Hostname: "localhost",
+	Port:     5432,
+	Name:     "vulcanize_private",
+}
+
+type Exporter interface {
+	Export() []transformer.TransformerInitializer
+}
+
+var _ = Describe("Generator test", func() {
+	var g p2.Generator
+	var goPath, soPath string
+	var err error
+	var bc core.BlockChain
+	var db *postgres.DB
+	var hr repositories.HeaderRepository
+	var headerID int64
+	viper.SetConfigName("compose")
+	viper.AddConfigPath("$GOPATH/src/github.com/vulcanize/vulcanizedb/environments/")
+
+	BeforeEach(func() {
+		goPath, soPath, err = genConfig.GetPluginPaths()
+		Expect(err).ToNot(HaveOccurred())
+		g, err = p2.NewGenerator(genConfig, dbConfig)
+		Expect(err).ToNot(HaveOccurred())
+		err = g.GenerateExporterPlugin()
+		Expect(err).ToNot(HaveOccurred())
+	})
+
+	AfterEach(func() {
+		err := helpers.ClearFiles(goPath, soPath)
+		Expect(err).ToNot(HaveOccurred())
+	})
+
+	Describe("GenerateTransformerPlugin", func() {
+		It("It bundles the specified transformer initializers into a Exporter object and creates .so", func() {
+			plug, err := plugin.Open(soPath)
+			Expect(err).ToNot(HaveOccurred())
+			symExporter, err := plug.Lookup("Exporter")
+			Expect(err).ToNot(HaveOccurred())
+			exporter, ok := symExporter.(Exporter)
+			Expect(ok).To(Equal(true))
+			initializers := exporter.Export()
+			Expect(len(initializers)).To(Equal(2))
+		})
+
+		It("Loads our generated Exporter and uses it to import an arbitrary set of TransformerInitializers that we can execute over", func() {
+			db, bc = test_helpers.SetupDBandBC()
+			defer test_helpers.TearDown(db)
+
+			hr = repositories.NewHeaderRepository(db)
+			header1, err := bc.GetHeaderByNumber(9377319)
+			Expect(err).ToNot(HaveOccurred())
+			headerID, err = hr.CreateOrUpdateHeader(header1)
+			Expect(err).ToNot(HaveOccurred())
+
+			plug, err := plugin.Open(soPath)
+			Expect(err).ToNot(HaveOccurred())
+			symExporter, err := plug.Lookup("Exporter")
+			Expect(err).ToNot(HaveOccurred())
+			exporter, ok := symExporter.(Exporter)
+			Expect(ok).To(Equal(true))
+			initializers := exporter.Export()
+
+			w := watcher.NewWatcher(db, bc)
+			w.AddTransformers(initializers)
+			err = w.Execute()
+			Expect(err).ToNot(HaveOccurred())
+
+			type model struct {
+				Ilk              string
+				Urn              string
+				Ink              string
+				Art              string
+				IArt             string
+				Tab              string
+				NFlip            string
+				LogIndex         uint   `db:"log_idx"`
+				TransactionIndex uint   `db:"tx_idx"`
+				Raw              []byte `db:"raw_log"`
+				Id               int64  `db:"id"`
+				HeaderId         int64  `db:"header_id"`
+			}
+
+			returned := model{}
+
+			err = db.Get(&returned, `SELECT * FROM maker.bite WHERE header_id = $1`, headerID)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(returned.Ilk).To(Equal("ETH"))
+			Expect(returned.Urn).To(Equal("0x0000d8b4147eDa80Fec7122AE16DA2479Cbd7ffB"))
+			Expect(returned.Ink).To(Equal("80000000000000000000"))
+			Expect(returned.Art).To(Equal("11000000000000000000000"))
+			Expect(returned.IArt).To(Equal("12496609999999999999992"))
+			Expect(returned.Tab).To(Equal("11000000000000000000000"))
+			Expect(returned.NFlip).To(Equal("7"))
+			Expect(returned.TransactionIndex).To(Equal(uint(1)))
+			Expect(returned.LogIndex).To(Equal(uint(4)))
+		})
+	})
+})
@@ -0,0 +1,61 @@
+package helpers
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"syscall"
+
+	"github.com/mitchellh/go-homedir"
+)
+
+func CleanPath(str string) (string, error) {
+	path, err := homedir.Expand(filepath.Clean(str))
+	if err != nil {
+		return "", err
+	}
+	if strings.Contains(path, "$GOPATH") {
+		env := os.Getenv("GOPATH")
+		spl := strings.Split(path, "$GOPATH")[1]
+		path = filepath.Join(env, spl)
+	}
+
+	return path, nil
+}
+
+func ClearFiles(files ...string) error {
+	for _, file := range files {
+		if _, err := os.Stat(file); err == nil {
+			err = os.Remove(file)
+			if err != nil {
+				return err
+			}
+		} else if os.IsNotExist(err) {
+			// fall through
+		} else {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func CopyFile(src, dst string) error {
+	in, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer in.Close()
+	out, err := os.OpenFile(dst, syscall.O_CREAT|syscall.O_EXCL|os.O_WRONLY, os.FileMode(0666)) // Doesn't overwrite files
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+
+	_, err = io.Copy(out, in)
+	if err != nil {
+		return err
+	}
+	return out.Close()
+}
@@ -0,0 +1,134 @@
+// VulcanizeDB
+// Copyright © 2018 Vulcanize
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package manager
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+
+	"github.com/vulcanize/vulcanizedb/pkg/config"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/helpers"
+)
+
+type MigrationManager interface {
+	RunMigrations() error
+}
+
+type manager struct {
+	GenConfig config.Plugin
+	DBConfig  config.Database
+	tmpMigDir string
+}
+
+func NewMigrationManager(gc config.Plugin, dbc config.Database) *manager {
+	return &manager{
+		GenConfig: gc,
+		DBConfig:  dbc,
+	}
+}
+
+func (m *manager) RunMigrations() error {
+	// Get paths to db migrations
+	paths, err := m.GenConfig.GetMigrationsPaths()
+	if err != nil {
+		return err
+	}
+	if len(paths) < 1 {
+		return nil
+	}
+
+	// Init directory for temporary copies
+	err = m.setupMigrationEnv()
+	if err != nil {
+		return err
+	}
+	defer m.cleanUp()
+
+	// Create temporary copies of migrations to the temporary migrationDir
+	// These tmps are identical except they have had `1` added in front of their unix_timestamps
+	// As such, they will be ran on top of all core migrations (at least, for the next ~317 years)
+	// But will still be ran in the same order relative to one another
+	// TODO: Less hacky way of handing migrations
+	err = m.createMigrationCopies(paths)
+	if err != nil {
+		return err
+	}
+
+	// Run the copied migrations
+	pgStr := fmt.Sprintf("postgres://%s:%d/%s?sslmode=disable", m.DBConfig.Hostname, m.DBConfig.Port, m.DBConfig.Name)
+	err = exec.Command("migrate", "-path", m.tmpMigDir, "-database", pgStr, "up").Run()
+	if err != nil {
+		return errors.New(fmt.Sprintf("db migrations for plugin transformers failed: %s", err.Error()))
+	}
+
+	return nil
+}
+
+func (m *manager) setupMigrationEnv() error {
+	// Initialize temp directory for transformer migrations
+	var err error
+	m.tmpMigDir, err = helpers.CleanPath("$GOPATH/src/github.com/vulcanize/vulcanizedb/db/plugin_migrations")
+	if err != nil {
+		return err
+	}
+	err = os.RemoveAll(m.tmpMigDir)
+	if err != nil {
+		return errors.New(fmt.Sprintf("unable to remove file found at %s where tmp directory needs to be written", m.tmpMigDir))
+	}
+	err = os.Mkdir(m.tmpMigDir, os.FileMode(0777))
+	if err != nil {
+		return errors.New(fmt.Sprintf("unable to create temporary migration directory %s", m.tmpMigDir))
+	}
+
+	return nil
+}
+
+func (m *manager) createMigrationCopies(paths []string) error {
+	for _, path := range paths {
+		dir, err := ioutil.ReadDir(path)
+		if err != nil {
+			return err
+		}
+		for _, file := range dir {
+			if file.IsDir() || len(file.Name()) < 15 || filepath.Ext(file.Name()) != ".sql" { // (10 digit unix time stamp + x + .sql) is bare minimum
+				continue
+			}
+			_, err := strconv.Atoi(file.Name()[:10])
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "migration file name %s does not posses 10 digit timestamp prefix\r\n", file.Name())
+				continue
+			}
+			src := filepath.Join(path, file.Name())
+			dst := filepath.Join(m.tmpMigDir, "1"+file.Name())
+			err = helpers.CopyFile(src, dst)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func (m *manager) cleanUp() error {
+	return os.RemoveAll(m.tmpMigDir)
+}
@@ -0,0 +1,65 @@
+package test_helpers
+
+import (
+	"github.com/ethereum/go-ethereum/ethclient"
+	"github.com/ethereum/go-ethereum/rpc"
+	. "github.com/onsi/gomega"
+
+	"github.com/vulcanize/vulcanizedb/pkg/config"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+	"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
+	"github.com/vulcanize/vulcanizedb/pkg/geth"
+	"github.com/vulcanize/vulcanizedb/pkg/geth/client"
+	rpc2 "github.com/vulcanize/vulcanizedb/pkg/geth/converters/rpc"
+	"github.com/vulcanize/vulcanizedb/pkg/geth/node"
+)
+
+func SetupDBandBC() (*postgres.DB, core.BlockChain) {
+	infuraIPC := "http://kovan0.vulcanize.io:8545"
+	rawRpcClient, err := rpc.Dial(infuraIPC)
+	Expect(err).NotTo(HaveOccurred())
+	rpcClient := client.NewRpcClient(rawRpcClient, infuraIPC)
+	ethClient := ethclient.NewClient(rawRpcClient)
+	blockChainClient := client.NewEthClient(ethClient)
+	node := node.MakeNode(rpcClient)
+	transactionConverter := rpc2.NewRpcTransactionConverter(ethClient)
+	blockChain := geth.NewBlockChain(blockChainClient, rpcClient, node, transactionConverter)
+
+	db, err := postgres.NewDB(config.Database{
+		Hostname: "localhost",
+		Name:     "vulcanize_private",
+		Port:     5432,
+	}, blockChain.Node())
+	Expect(err).NotTo(HaveOccurred())
+
+	return db, blockChain
+}
+
+func TearDown(db *postgres.DB) {
+	tx, err := db.Begin()
+	Expect(err).NotTo(HaveOccurred())
+
+	_, err = tx.Exec(`DELETE FROM headers`)
+	Expect(err).NotTo(HaveOccurred())
+
+	_, err = tx.Exec(`DELETE FROM logs`)
+	Expect(err).NotTo(HaveOccurred())
+
+	_, err = tx.Exec(`DELETE FROM log_filters`)
+	Expect(err).NotTo(HaveOccurred())
+
+	_, err = tx.Exec(`DELETE FROM transactions`)
+	Expect(err).NotTo(HaveOccurred())
+
+	_, err = tx.Exec(`DELETE FROM receipts`)
+	Expect(err).NotTo(HaveOccurred())
+
+	_, err = tx.Exec(`DELETE FROM checked_headers`)
+	Expect(err).NotTo(HaveOccurred())
+
+	_, err = tx.Exec(`DELETE FROM maker.bite`)
+	Expect(err).NotTo(HaveOccurred())
+
+	err = tx.Commit()
+	Expect(err).NotTo(HaveOccurred())
+}
@@ -0,0 +1,3 @@
+### Test
+
+This empty directory is for holding the temporary .so and .go files generated during the generator_tests
@@ -0,0 +1,92 @@
+// VulcanizeDB
+// Copyright © 2018 Vulcanize
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package writer
+
+import (
+	"errors"
+	"fmt"
+
+	. "github.com/dave/jennifer/jen"
+
+	"github.com/vulcanize/vulcanizedb/pkg/config"
+	"github.com/vulcanize/vulcanizedb/pkg/plugin/helpers"
+)
+
+type PluginWriter interface {
+	WritePlugin() error
+}
+
+type writer struct {
+	GenConfig config.Plugin
+}
+
+func NewPluginWriter(gc config.Plugin) *writer {
+	return &writer{
+		GenConfig: gc,
+	}
+}
+
+// Generates the plugin code
+func (w *writer) WritePlugin() error {
+	// Setup plugin file paths
+	goFile, err := w.setupFilePath()
+	if err != nil {
+		return err
+	}
+
+	// Begin code generation
+	f := NewFile("main")
+	f.HeaderComment("This is a plugin generated to export the configured transformer initializers")
+
+	// Import TransformerInitializers specified in config
+	f.ImportAlias("github.com/vulcanize/vulcanizedb/libraries/shared/transformer", "interface")
+	for alias, imp := range w.GenConfig.Initializers {
+		f.ImportAlias(imp, alias)
+	}
+
+	// Collect TransformerInitializer names
+	importedInitializers := make([]Code, 0, len(w.GenConfig.Initializers))
+	for _, path := range w.GenConfig.Initializers {
+		importedInitializers = append(importedInitializers, Qual(path, "TransformerInitializer"))
+	}
+
+	// Create Exporter variable with method to export the set of the imported TransformerInitializers
+	f.Type().Id("exporter").String()
+	f.Var().Id("Exporter").Id("exporter")
+	f.Func().Params(Id("e").Id("exporter")).Id("Export").Params().Index().Qual(
+		"github.com/vulcanize/vulcanizedb/libraries/shared/transformer",
+		"TransformerInitializer").Block(
+		Return(Index().Qual(
+			"github.com/vulcanize/vulcanizedb/libraries/shared/transformer",
+			"TransformerInitializer").Values(importedInitializers...))) // Exports the collected TransformerInitializers
+
+	// Write code to destination file
+	err = f.Save(goFile)
+	if err != nil {
+		return errors.New(fmt.Sprintf("failed to save generated .go file: %s\r\n%s", goFile, err.Error()))
+	}
+	return nil
+}
+
+func (w *writer) setupFilePath() (string, error) {
+	goFile, soFile, err := w.GenConfig.GetPluginPaths()
+	if err != nil {
+		return "", err
+	}
+	// Clear .go and .so files of the same name if they exist
+	return goFile, helpers.ClearFiles(goFile, soFile)
+}