Enable running locally using docker; add db migrations

Author: jarri-abidi

Dockerfile

@@ -0,0 +1,21 @@
+# Build stage
+FROM golang:1.19-alpine3.16 AS builder
+WORKDIR /app
+COPY go.mod .
+COPY go.sum .
+RUN go mod download
+COPY . .
+RUN go build -o main cmd/main.go
+
+# Run stage
+FROM alpine:3.16
+WORKDIR /app
+COPY --from=builder /app/main .
+COPY app.env .
+COPY start.sh .
+COPY wait-for.sh .
+RUN chmod +x start.sh wait-for.sh
+COPY postgres/migrations ./postgres/migrations
+
+EXPOSE 8085
+CMD [ "/app/main" ]

README.md

@@ -1,2 +1,12 @@
 # todo
 Example project meant to demonstrate a production-ready, enterprise-style REST API using go-kit. 
+
+To run:
+```
+docker-compose build && docker-compose up -d
+```
+
+To stop:
+```
+docker-compose down
+```

app.env

@@ -3,3 +3,6 @@ SERVER_WRITE_TIMEOUT=15s
 SERVER_READ_TIMEOUT=15s
 SERVER_IDLE_TIMEOUT=60s
 GRACEFUL_SHUTDOWN_TIMEOUT=30s
+DB_SOURCE=postgresql://root:secret@postgres:5432/todo?sslmode=disable
+DB_CONNECT_TIMEOUT=5s
+OTEL_EXPORTER_JAEGER_ENDPOINT=http://jaeger:14268/api/traces

cmd/main.go

@@ -2,20 +2,23 @@ package main
 
 import (
 	"context"
-	"database/sql"
-	"fmt"
 	"net/http"
 	"os"
 	"os/signal"
 
 	"github.com/go-kit/log"
+	_ "github.com/golang-migrate/migrate/v4/database/postgres"
+	_ "github.com/golang-migrate/migrate/v4/source/file"
 	_ "github.com/lib/pq"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"go.opentelemetry.io/contrib/propagators/b3"
 	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/exporters/jaeger"
 	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/sdk/resource"
 	"go.opentelemetry.io/otel/sdk/trace"
+	semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
 
 	"github.com/jarri-abidi/todo/checklist"
 	"github.com/jarri-abidi/todo/config"
@@ -31,36 +34,37 @@ func main() {
 		os.Exit(1)
 	}
 
-	var db *sql.DB
-	{
-		ctx, cancel := context.WithTimeout(context.Background(), conf.DBConnectTimeout)
-		defer cancel()
-		db, err = postgres.NewDB(ctx, conf.DBSource)
-		if err != nil {
-			logger.Log("msg", "could not connect to postgres", "err", err)
-			os.Exit(1)
-		}
+	ctx, cancel := context.WithTimeout(context.Background(), conf.DBConnectTimeout)
+	defer cancel()
+	db, err := postgres.NewDB(ctx, conf.DBSource)
+	if err != nil {
+		logger.Log("msg", "could not connect to postgres", "err", err)
+		os.Exit(1)
 	}
 
-	var exporter trace.SpanExporter
-	{
-		exporter, err = jaeger.New(jaeger.WithCollectorEndpoint())
-		if err != nil {
-			logger.Log("msg", "could not create jaeger exporter", "err", err)
-			os.Exit(1)
-		}
+	if err = postgres.Migrate("file://postgres/migrations", db); err != nil {
+		logger.Log("msg", "could not run postgres schema migrations", "err", err)
+		os.Exit(1)
 	}
 
-	var tp *trace.TracerProvider
-	{
-		tp = trace.NewTracerProvider(
-			trace.WithSampler(trace.AlwaysSample()),
-			trace.WithBatcher(exporter),
-		)
-		otel.SetTracerProvider(tp)
-		otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(b3.New()))
+	exporter, err := jaeger.New(jaeger.WithCollectorEndpoint())
+	if err != nil {
+		logger.Log("msg", "could not create jaeger exporter", "err", err)
+		os.Exit(1)
 	}
 
+	tp := trace.NewTracerProvider(
+		trace.WithSampler(trace.AlwaysSample()),
+		trace.WithBatcher(exporter),
+		trace.WithResource(resource.NewWithAttributes(
+			semconv.SchemaURL,
+			semconv.ServiceNameKey.String("todo"),
+			attribute.String("environment", "dev"),
+		)),
+	)
+	otel.SetTracerProvider(tp)
+	otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(b3.New()))
+
 	tasks := postgres.NewTaskRepository(db)
 
 	var service checklist.Service
@@ -79,14 +83,6 @@ func main() {
 		Handler:      mux,
 	}
 
-	fmt.Println(`
-	 _____          _       
-   	/__   \___   __| | ___  
-	  / /\/ _ \ / _  |/ _ \ 
-	 / / | (_) | (_| | (_) |
-	 \/   \___/ \__,_|\___/ 
-	`)
-
 	sig := make(chan os.Signal, 1)
 	signal.Notify(sig, os.Interrupt)
 
@@ -100,19 +96,19 @@ func main() {
 
 	logger.Log("received", <-sig, "msg", "terminating")
 
-	if err := server.Shutdown(context.Background()); err != nil {
+	if err = server.Shutdown(context.Background()); err != nil {
 		logger.Log("msg", "could not shutdown http server", "err", err)
 	}
 
-	if err := db.Close(); err != nil {
+	if err = db.Close(); err != nil {
 		logger.Log("msg", "could not close db connection", "err", err)
 	}
 
-	if err := tp.Shutdown(context.Background()); err != nil {
+	if err = tp.Shutdown(context.Background()); err != nil {
 		logger.Log("msg", "could not shutdown tracer provider", "err", err)
 	}
 
-	if err := exporter.Shutdown(context.Background()); err != nil {
+	if err = exporter.Shutdown(context.Background()); err != nil {
 		logger.Log("msg", "could not shutdown traces exporter", "err", err)
 	}
 

config/config.go

@@ -11,13 +11,14 @@ import (
 // Config stores all configurations of the application.
 // The values are read from a file or environment variables.
 type Config struct {
-	ServerAddress           string        `envconfig:"SERVER_ADDRESS"`
-	ServerWriteTimeout      time.Duration `envconfig:"SERVER_WRITE_TIMEOUT"`
-	ServerReadTimeout       time.Duration `envconfig:"SERVER_READ_TIMEOUT"`
-	ServerIdleTimeout       time.Duration `envconfig:"SERVER_IDLE_TIMEOUT"`
-	GracefulShutdownTimeout time.Duration `envconfig:"GRACEFUL_SHUTDOWN_TIMEOUT"`
-	DBSource                string        `envconfig:"DB_SOURCE"`
-	DBConnectTimeout        time.Duration `envconfig:"DB_CONNECT_TIMEOUT"`
+	ServerAddress              string        `envconfig:"SERVER_ADDRESS"`
+	ServerWriteTimeout         time.Duration `envconfig:"SERVER_WRITE_TIMEOUT"`
+	ServerReadTimeout          time.Duration `envconfig:"SERVER_READ_TIMEOUT"`
+	ServerIdleTimeout          time.Duration `envconfig:"SERVER_IDLE_TIMEOUT"`
+	GracefulShutdownTimeout    time.Duration `envconfig:"GRACEFUL_SHUTDOWN_TIMEOUT"`
+	DBSource                   string        `envconfig:"DB_SOURCE"`
+	DBConnectTimeout           time.Duration `envconfig:"DB_CONNECT_TIMEOUT"`
+	OTELExporterJaegerEndpoint string        `envconfig:"OTEL_EXPORTER_JAEGER_ENDPOINT"`
 }
 
 // Load returns configuration from file or environment variables.

docker-compose.yml

@@ -0,0 +1,30 @@
+version: "3.9"
+services:
+  postgres:
+    image: postgres:14-alpine
+    environment:
+      - POSTGRES_USER=root
+      - POSTGRES_PASSWORD=secret
+      - POSTGRES_DB=todo
+  jaeger:
+    image: jaegertracing/all-in-one:latest
+    ports:
+      - "16687:16686"
+  todo:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    ports:
+      - "8085:8085"
+    environment:
+      - DB_SOURCE=postgresql://root:secret@postgres:5432/todo?sslmode=disable
+    depends_on:
+      - postgres
+    entrypoint:
+      [
+        "/app/wait-for.sh",
+        "postgres:5432",
+        "--",
+        "/app/start.sh"
+      ]
+    command: [ "/app/main" ]

go.mod

@@ -5,15 +5,16 @@ go 1.14
 require (
 	github.com/go-kit/kit v0.12.0
 	github.com/go-kit/log v0.2.0
+	github.com/golang-migrate/migrate/v4 v4.15.2
 	github.com/gorilla/mux v1.8.0
 	github.com/joho/godotenv v1.4.0
 	github.com/kelseyhightower/envconfig v1.4.0
-	github.com/lib/pq v1.10.7 // indirect
+	github.com/lib/pq v1.10.7
 	github.com/pkg/errors v0.9.1
 	github.com/prometheus/client_golang v1.11.0
 	github.com/stretchr/testify v1.8.0
 	go.opentelemetry.io/contrib/instrumentation/github.com/go-kit/kit/otelkit v0.35.0
-	go.opentelemetry.io/contrib/propagators/b3 v1.10.0 // indirect
+	go.opentelemetry.io/contrib/propagators/b3 v1.10.0
 	go.opentelemetry.io/otel v1.10.0
 	go.opentelemetry.io/otel/exporters/jaeger v1.10.0
 	go.opentelemetry.io/otel/sdk v1.10.0