change API to pgxpool

cmd/apollo-api/main.go

@@ -1,15 +1,17 @@
 package main
 
 import (
-	"database/sql"
+	"context"
 	"fmt"
 	"log"
 	"net/http"
 	"os"
+	"os/signal"
+	"syscall"
 
 	"github.com/DataDog/datadog-go/statsd"
+	"github.com/jackc/pgx/v4/pgxpool"
 	"github.com/joho/godotenv"
-	_ "github.com/lib/pq"
 	"github.com/sirupsen/logrus"
 
 	"github.com/christianselig/apollo-backend/internal/data"
@@ -23,12 +25,15 @@ type config struct {
 type application struct {
 	cfg    config
 	logger *logrus.Logger
-	db     *sql.DB
+	pool   *pgxpool.Pool
 	models *data.Models
 	client *reddit.Client
 }
 
 func main() {
+	_ = godotenv.Load()
+	ctx, cancel := context.WithCancel(context.Background())
+
 	var logger *logrus.Logger
 	{
 		logger = logrus.New()
@@ -42,22 +47,27 @@ func main() {
 		}
 	}
 
-	if err := godotenv.Load(); err != nil {
-		logger.Printf("Couldn't find .env so I will read from existing ENV.")
-	}
-
 	var cfg config
 
-	dburl, ok := os.LookupEnv("DATABASE_CONNECTION_POOL_URL")
-	if !ok {
-		dburl = os.Getenv("DATABASE_URL")
+	// Set up Postgres connection
+	var pool *pgxpool.Pool
+	{
+		url := fmt.Sprintf("%s?sslmode=require", os.Getenv("DATABASE_CONNECTION_POOL_URL"))
+		config, err := pgxpool.ParseConfig(url)
+		if err != nil {
+			panic(err)
 		}
 
-	db, err := sql.Open("postgres", fmt.Sprintf("%s?binary_parameters=yes", dburl))
+		// Setting the build statement cache to nil helps this work with pgbouncer
+		config.ConnConfig.BuildStatementCache = nil
+		config.ConnConfig.PreferSimpleProtocol = true
+
+		pool, err = pgxpool.ConnectConfig(ctx, config)
 		if err != nil {
-		log.Fatal(err)
+			panic(err)
+		}
+		defer pool.Close()
 	}
-	defer db.Close()
 
 	statsd, err := statsd.New("127.0.0.1:8125")
 	if err != nil {
@@ -73,8 +83,8 @@ func main() {
 	app := &application{
 		cfg,
 		logger,
-		db,
-		data.NewModels(db),
+		pool,
+		data.NewModels(ctx, pool),
 		rc,
 	}
 
@@ -89,6 +99,19 @@ func main() {
 	}
 
 	logger.Printf("starting server on %s", srv.Addr)
-	err = srv.ListenAndServe()
-	logger.Fatal(err)
+	go srv.ListenAndServe()
+
+	signals := make(chan os.Signal, 1)
+	signal.Notify(signals, syscall.SIGINT, syscall.SIGTERM)
+	defer signal.Stop(signals)
+
+	<-signals // wait for signal
+
+	srv.Shutdown(ctx)
+	cancel()
+
+	go func() {
+		<-signals // hard exit on second signal (in case shutdown gets stuck)
+		os.Exit(1)
+	}()
 }

internal/data/accounts.go

@@ -1,8 +1,11 @@
 package data
 
 import (
-	"database/sql"
+	"context"
 	"strings"
+
+	"github.com/jackc/pgx/v4"
+	"github.com/jackc/pgx/v4/pgxpool"
 )
 
 type Account struct {
@@ -21,11 +24,13 @@ func (a *Account) NormalizedUsername() string {
 }
 
 type AccountModel struct {
-	DB *sql.DB
+	ctx  context.Context
+	pool *pgxpool.Pool
 }
 
 func (am *AccountModel) Upsert(a *Account) error {
-	query := `
+	return am.pool.BeginFunc(am.ctx, func(tx pgx.Tx) error {
+		stmt := `
 				INSERT INTO accounts (username, account_id, access_token, refresh_token, expires_at, last_message_id, device_count, last_checked_at)
 					VALUES ($1, $2, $3, $4, $5, '', 0, 0)
 					ON CONFLICT(username)
@@ -37,9 +42,18 @@ func (am *AccountModel) Upsert(a *Account) error {
 							last_message_id = $6,
 							last_checked_at = $7
 					RETURNING id`
-
-	args := []interface{}{a.NormalizedUsername(), a.AccountID, a.AccessToken, a.RefreshToken, a.ExpiresAt, a.LastMessageID, a.LastCheckedAt}
-	return am.DB.QueryRow(query, args...).Scan(&a.ID)
+		return tx.QueryRow(
+			am.ctx,
+			stmt,
+			a.NormalizedUsername(),
+			a.AccountID,
+			a.AccessToken,
+			a.RefreshToken,
+			a.ExpiresAt,
+			a.LastMessageID,
+			a.LastCheckedAt,
+		).Scan(&a.ID)
+	})
 }
 
 func (am *AccountModel) Delete(id int64) error {

internal/data/device_accounts.go

@@ -1,6 +1,10 @@
 package data
 
-import "database/sql"
+import (
+	"context"
+
+	"github.com/jackc/pgx/v4/pgxpool"
+)
 
 type DeviceAccount struct {
 	ID        int64
@@ -9,30 +13,29 @@ type DeviceAccount struct {
 }
 
 type DeviceAccountModel struct {
-	DB *sql.DB
+	ctx  context.Context
+	pool *pgxpool.Pool
 }
 
 func (dam *DeviceAccountModel) Associate(accountID int64, deviceID int64) error {
-	query := `
+	stmt := `
 		INSERT INTO devices_accounts (account_id, device_id)
 		VALUES ($1, $2)
 		ON CONFLICT (account_id, device_id) DO NOTHING
 		RETURNING id`
-
-	args := []interface{}{accountID, deviceID}
-	if err := dam.DB.QueryRow(query, args...).Err(); err != nil {
+	if _, err := dam.pool.Exec(dam.ctx, stmt, accountID, deviceID); err != nil {
 		return err
 	}
 
 	// Update account counter
-	query = `
+	stmt = `
 		UPDATE accounts
 		SET device_count = (
 			SELECT COUNT(*) FROM devices_accounts WHERE account_id = $1
 		)
 		WHERE id = $1`
-	args = []interface{}{accountID}
-	return dam.DB.QueryRow(query, args...).Err()
+	_, err := dam.pool.Exec(dam.ctx, stmt, accountID)
+	return err
 }
 
 type MockDeviceAccountModel struct{}

internal/data/devices.go

@@ -1,9 +1,11 @@
 package data
 
 import (
-	"database/sql"
-	"errors"
+	"context"
 	"time"
+
+	"github.com/jackc/pgx/v4"
+	"github.com/jackc/pgx/v4/pgxpool"
 )
 
 type Device struct {
@@ -14,46 +16,46 @@ type Device struct {
 }
 
 type DeviceModel struct {
-	DB *sql.DB
+	ctx  context.Context
+	pool *pgxpool.Pool
 }
 
 func (dm *DeviceModel) Upsert(d *Device) error {
 	d.LastPingedAt = time.Now().Unix()
 
-	query := `
+	return dm.pool.BeginFunc(dm.ctx, func(tx pgx.Tx) error {
+		stmt := `
 			INSERT INTO devices (apns_token, sandbox, last_pinged_at)
 			VALUES ($1, $2, $3)
 			ON CONFLICT(apns_token)
 			DO
 				UPDATE SET last_pinged_at = $3
 			RETURNING id`
-
-	args := []interface{}{d.APNSToken, d.Sandbox, d.LastPingedAt}
-	return dm.DB.QueryRow(query, args...).Scan(&d.ID)
+		return tx.QueryRow(
+			dm.ctx,
+			stmt,
+			d.APNSToken,
+			d.Sandbox,
+			d.LastPingedAt,
+		).Scan(&d.ID)
+	})
 }
 
 func (dm *DeviceModel) GetByAPNSToken(token string) (*Device, error) {
-	query := `
+	device := &Device{}
+	stmt := `
 		SELECT id, apns_token, sandbox, last_pinged_at
 		FROM devices
 		WHERE apns_token = $1`
 
-	device := &Device{}
-	err := dm.DB.QueryRow(query, token).Scan(
+	if err := dm.pool.QueryRow(dm.ctx, stmt, token).Scan(
 		&device.ID,
 		&device.APNSToken,
 		&device.Sandbox,
 		&device.LastPingedAt,
-	)
-
-	if err != nil {
-		switch {
-		case errors.Is(err, sql.ErrNoRows):
-			return nil, ErrRecordNotFound
-		default:
+	); err != nil {
 		return nil, err
 	}
-	}
 	return device, nil
 }
 

internal/data/models.go

@@ -1,8 +1,10 @@
 package data
 
 import (
-	"database/sql"
+	"context"
 	"errors"
+
+	"github.com/jackc/pgx/v4/pgxpool"
 )
 
 var (
@@ -25,11 +27,11 @@ type Models struct {
 	}
 }
 
-func NewModels(db *sql.DB) *Models {
+func NewModels(ctx context.Context, pool *pgxpool.Pool) *Models {
 	return &Models{
-		Accounts:        &AccountModel{DB: db},
-		Devices:         &DeviceModel{DB: db},
-		DevicesAccounts: &DeviceAccountModel{DB: db},
+		Accounts:        &AccountModel{ctx, pool},
+		Devices:         &DeviceModel{ctx, pool},
+		DevicesAccounts: &DeviceAccountModel{ctx, pool},
 	}
 }