Merge pull request #69 from 8thlight/watch_contract

* Add contracts table / start building out watch contracts

Gododir/main.go

@@ -36,6 +36,16 @@ func tasks(p *do.Project) {
 			do.M{"environment": environment, "startingNumber": startingNumber, "$in": "cmd/populate_blocks"})
 	})
 
+	p.Task("watchContract", nil, func(context *do.Context) {
+		environment := parseEnvironment(context)
+		contractHash := context.Args.MayString("", "contract-hash", "c")
+		if contractHash == "" {
+			log.Fatalln("--contract-hash required")
+		}
+		context.Start(`go run main.go --environment={{.environment}} --contract-hash={{.contractHash}}`,
+			do.M{"environment": environment, "contractHash": contractHash, "$in": "cmd/subscribe_contract"})
+	})
+
 	p.Task("migrate", nil, func(context *do.Context) {
 		environment := parseEnvironment(context)
 		cfg := cmd.LoadConfig(environment)

cmd/subscribe_contract/main.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"flag"
+
+	"github.com/8thlight/vulcanizedb/cmd"
+	"github.com/8thlight/vulcanizedb/pkg/core"
+	"github.com/8thlight/vulcanizedb/pkg/repositories"
+)
+
+func main() {
+	environment := flag.String("environment", "", "Environment name")
+	contractHash := flag.String("contract-hash", "", "contract-hash=x1234")
+	flag.Parse()
+	config := cmd.LoadConfig(*environment)
+	repository := repositories.NewPostgres(config.Database)
+	repository.CreateWatchedContract(core.WatchedContract{Hash: *contractHash})
+}

db/migrations/1510257608_add_contracts_table.down.sql

@@ -0,0 +1 @@
+DROP TABLE watched_contracts

db/migrations/1510257608_add_contracts_table.up.sql

@@ -0,0 +1,5 @@
+CREATE TABLE watched_contracts
+(
+  contract_id SERIAL PRIMARY KEY,
+  contract_hash VARCHAR(66)
+)

db/schema.sql

@@ -3,7 +3,7 @@
 --
 
 -- Dumped from database version 10.0
--- Dumped by pg_dump version 10.0
+-- Dumped by pg_dump version 10.1
 
 SET statement_timeout = 0;
 SET lock_timeout = 0;
@@ -118,6 +118,35 @@ CREATE SEQUENCE transactions_id_seq
 ALTER SEQUENCE transactions_id_seq OWNED BY transactions.id;
 
 
+--
+-- Name: watched_contracts; Type: TABLE; Schema: public; Owner: -
+--
+
+CREATE TABLE watched_contracts (
+    contract_id integer NOT NULL,
+    contract_hash character varying(66)
+);
+
+
+--
+-- Name: watched_contracts_contract_id_seq; Type: SEQUENCE; Schema: public; Owner: -
+--
+
+CREATE SEQUENCE watched_contracts_contract_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1;
+
+
+--
+-- Name: watched_contracts_contract_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
+--
+
+ALTER SEQUENCE watched_contracts_contract_id_seq OWNED BY watched_contracts.contract_id;
+
+
 --
 -- Name: blocks id; Type: DEFAULT; Schema: public; Owner: -
 --
@@ -132,6 +161,13 @@ ALTER TABLE ONLY blocks ALTER COLUMN id SET DEFAULT nextval('blocks_id_seq'::reg
 ALTER TABLE ONLY transactions ALTER COLUMN id SET DEFAULT nextval('transactions_id_seq'::regclass);
 
 
+--
+-- Name: watched_contracts contract_id; Type: DEFAULT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY watched_contracts ALTER COLUMN contract_id SET DEFAULT nextval('watched_contracts_contract_id_seq'::regclass);
+
+
 --
 -- Name: blocks blocks_pkey; Type: CONSTRAINT; Schema: public; Owner: -
 --
@@ -156,6 +192,14 @@ ALTER TABLE ONLY transactions
     ADD CONSTRAINT transactions_pkey PRIMARY KEY (id);
 
 
+--
+-- Name: watched_contracts watched_contracts_pkey; Type: CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY watched_contracts
+    ADD CONSTRAINT watched_contracts_pkey PRIMARY KEY (contract_id);
+
+
 --
 -- Name: block_number_index; Type: INDEX; Schema: public; Owner: -
 --

pkg/core/contract.go

@@ -0,0 +1,5 @@
+package core
+
+type WatchedContract struct {
+	Hash string
+}

pkg/repositories/in_memory.go

@@ -5,7 +5,18 @@ import (
 )
 
 type InMemory struct {
-	blocks map[int64]*core.Block
+	blocks           map[int64]*core.Block
+	watchedContracts map[string]*core.WatchedContract
+}
+
+func (repository *InMemory) CreateWatchedContract(watchedContract core.WatchedContract) error {
+	repository.watchedContracts[watchedContract.Hash] = &watchedContract
+	return nil
+}
+
+func (repository *InMemory) IsWatchedContract(contractHash string) bool {
+	_, present := repository.watchedContracts[contractHash]
+	return present
 }
 
 func (repository *InMemory) MissingBlockNumbers(startingBlockNumber int64, endingBlockNumber int64) []int64 {
@@ -20,7 +31,8 @@ func (repository *InMemory) MissingBlockNumbers(startingBlockNumber int64, endin
 
 func NewInMemory() *InMemory {
 	return &InMemory{
-		blocks: make(map[int64]*core.Block),
+		blocks:           make(map[int64]*core.Block),
+		watchedContracts: make(map[string]*core.WatchedContract),
 	}
 }
 

pkg/repositories/postgres.go

@@ -18,6 +18,10 @@ type Postgres struct {
 	Db *sqlx.DB
 }
 
+var (
+	ErrDBInsertFailed = errors.New("postgres: insert failed")
+)
+
 func NewPostgres(databaseConfig config.Database) Postgres {
 	connectString := config.DbConnectionString(databaseConfig)
 	db, err := sqlx.Connect("postgres", connectString)
@@ -27,9 +31,24 @@ func NewPostgres(databaseConfig config.Database) Postgres {
 	return Postgres{Db: db}
 }
 
-var (
-	ErrDBInsertFailed = errors.New("postgres: insert failed")
-)
+func (repository Postgres) CreateWatchedContract(contract core.WatchedContract) error {
+	_, err := repository.Db.Exec(
+		`INSERT INTO watched_contracts (contract_hash) VALUES ($1)`, contract.Hash)
+	if err != nil {
+		return ErrDBInsertFailed
+	}
+	return nil
+}
+
+func (repository Postgres) IsWatchedContract(contractHash string) bool {
+	var exists bool
+	err := repository.Db.QueryRow(
+		`SELECT exists(select 1 from watched_contracts where contract_hash=$1) FROM watched_contracts`, contractHash).Scan(&exists)
+	if err != nil && err != sql.ErrNoRows {
+		log.Fatalf("error checking if row exists %v", err)
+	}
+	return exists
+}
 
 func (repository Postgres) MaxBlockNumber() int64 {
 	var highestBlockNumber int64

pkg/repositories/repository.go

@@ -8,4 +8,6 @@ type Repository interface {
 	FindBlockByNumber(blockNumber int64) *core.Block
 	MaxBlockNumber() int64
 	MissingBlockNumbers(startingBlockNumber int64, endingBlockNumber int64) []int64
+	CreateWatchedContract(contract core.WatchedContract) error
+	IsWatchedContract(contractHash string) bool
 }

pkg/repositories/repository_test.go

@@ -195,6 +195,13 @@ var _ = Describe("Repositories", func() {
 				Expect(repository.MissingBlockNumbers(1, 5)).To(Equal([]int64{1, 2, 4, 5}))
 			})
 
+			It("Adds a contract to the watched_contracts table", func() {
+				repository.CreateWatchedContract(core.WatchedContract{Hash: "x123"})
+
+				Expect(repository.IsWatchedContract("x123")).To(BeTrue())
+				Expect(repository.IsWatchedContract("x456")).To(BeFalse())
+			})
+
 		})
 
 		Describe("The max block numbers", func() {

scripts/create_migration

@@ -2,7 +2,7 @@
 
 if [ $# -eq 1 ]
 then
-  migrate create -dir ./migrations -ext sql $1
+  migrate create -dir ./db/migrations -ext sql $1
 else
   echo "**An Error Occurred**"
   echo "Usage: ./scripts/create_migration <migration-name>"