feat: use connection pooling

Using a single connection is not thread-safe and should not be used in
applications like this where several requests may be processed at a
time.

This also makes it more reliable. Previously the db connection could not
recover from a DB server restart. With connection pooling it is now able
to recover. May not be perfect but is good enough atm.

Closes #24.

cmd/main.go

@@ -3,13 +3,12 @@ package main
 import (
 	"context"
 	"fmt"
-	"github.com/crazybolillo/eryth/internal/bouncer"
 	"github.com/crazybolillo/eryth/internal/handler"
 	"github.com/crazybolillo/eryth/internal/service"
 	"github.com/go-chi/chi/v5"
 	"github.com/go-chi/chi/v5/middleware"
 	"github.com/go-chi/httplog/v2"
-	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgxpool"
 	"log/slog"
 	"net/http"
 	"net/url"
@@ -53,12 +52,12 @@ func serve(ctx context.Context) error {
 		slog.String("database", u.Path[1:]),
 	)
 
-	conn, err := pgx.Connect(ctx, os.Getenv("DATABASE_URL"))
+	pool, err := pgxpool.New(ctx, os.Getenv("DATABASE_URL"))
 	if err != nil {
 		slog.Error("failed to establish database connection", slog.String("reason", err.Error()))
 		return err
 	}
-	defer conn.Close(ctx)
+	defer pool.Close()
 
 	r := chi.NewRouter()
 	r.Use(httplog.RequestLogger(httplog.NewLogger("eryth", httplog.Options{
@@ -68,10 +67,10 @@ func serve(ctx context.Context) error {
 	})))
 	r.Use(middleware.AllowContentEncoding("application/json"))
 
-	endpoint := handler.Endpoint{Service: &service.EndpointService{Cursor: conn}}
+	endpoint := handler.Endpoint{Service: &service.EndpointService{Cursor: pool}}
 	r.Mount("/endpoints", endpoint.Router())
 
-	checker := &bouncer.Bouncer{Conn: conn}
+	checker := &service.Bouncer{Cursor: pool}
 	authorization := handler.Authorization{Bouncer: checker}
 	r.Mount("/bouncer", authorization.Router())
 

docs/swagger.yaml

@@ -1,18 +1,18 @@
 definitions:
-  bouncer.Response:
+  handler.AuthorizationRequest:
     properties:
-      allow:
-        type: boolean
-      callerid:
+      endpoint:
         type: string
-      destination:
+      extension:
         type: string
     type: object
-  handler.AuthorizationRequest:
+  model.BouncerResponse:
     properties:
-      endpoint:
+      allow:
+        type: boolean
+      callerid:
         type: string
-      extension:
+      destination:
         type: string
     type: object
   model.Endpoint:
@@ -128,7 +128,7 @@ paths:
         "200":
           description: OK
           schema:
-            $ref: '#/definitions/bouncer.Response'
+            $ref: '#/definitions/model.BouncerResponse'
         "400":
           description: Bad Request
         "500":

go.mod

@@ -11,6 +11,8 @@ require (
 require (
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
+	github.com/jackc/puddle/v2 v2.2.1 // indirect
 	golang.org/x/crypto v0.17.0 // indirect
+	golang.org/x/sync v0.1.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
 )

internal/handler/authorization.go

@@ -3,14 +3,14 @@ package handler
 import (
 	"context"
 	"encoding/json"
-	"github.com/crazybolillo/eryth/internal/bouncer"
+	"github.com/crazybolillo/eryth/internal/model"
 	"github.com/go-chi/chi/v5"
 	"log/slog"
 	"net/http"
 )
 
 type CallBouncer interface {
-	Check(ctx context.Context, endpoint, dialed string) bouncer.Response
+	Check(ctx context.Context, endpoint, dialed string) model.BouncerResponse
 }
 
 type Authorization struct {
@@ -34,7 +34,7 @@ func (e *Authorization) Router() chi.Router {
 // @Accept json
 // @Produce json
 // @Param payload body AuthorizationRequest true "Action to be reviewed"
-// @Success 200 {object} bouncer.Response
+// @Success 200 {object} model.BouncerResponse
 // @Failure 400
 // @Failure 500
 // @Tags bouncer

internal/model/bouncer.go

@@ -0,0 +1,7 @@
+package model
+
+type BouncerResponse struct {
+	Allow       bool   `json:"allow"`
+	Destination string `json:"destination"`
+	CallerID    string `json:"callerid"`
+}

internal/bouncer/bouncer.go → internal/service/bouncer.go

@@ -1,25 +1,19 @@
-package bouncer
+package service
 
 import (
 	"context"
 	"github.com/crazybolillo/eryth/internal/db"
+	"github.com/crazybolillo/eryth/internal/model"
 	"github.com/crazybolillo/eryth/internal/sqlc"
-	"github.com/jackc/pgx/v5"
 	"log/slog"
 )
 
-type Response struct {
-	Allow       bool   `json:"allow"`
-	Destination string `json:"destination"`
-	CallerID    string `json:"callerid"`
-}
-
 type Bouncer struct {
-	*pgx.Conn
+	Cursor
 }
 
-func (b *Bouncer) Check(ctx context.Context, endpoint, dialed string) Response {
-	result := Response{
+func (b *Bouncer) Check(ctx context.Context, endpoint, dialed string) model.BouncerResponse {
+	result := model.BouncerResponse{
 		Allow: false,
 	}
 
@@ -44,7 +38,7 @@ func (b *Bouncer) Check(ctx context.Context, endpoint, dialed string) Response {
 		return result
 	}
 
-	return Response{
+	return model.BouncerResponse{
 		Allow:       true,
 		Destination: row.ID,
 		CallerID:    row.Callerid.String,