feat(slack): implement slack oauth2 service

.env.example

@@ -18,6 +18,11 @@ REDIS_PORT=6379
 REDIS_PASSWORD=zenreply
 REDIS_DB=0
 
+# --- Slack ---
+SLACK_CLIENT_ID=<SLACK_CLIENT_ID>
+SLACK_CLIENT_SECRET=<SLACK_CLIENT_SECRET>
+SLACK_SIGNING_SECRET=<SLACK_SIGNING_SECRET>
+
 # --- JWT ---
 JWT_SECRET=6ef0c2d5179f616e653915dc66844a763b80ef4ddac87953d4631290fe30de8a
 JWT_EXPIRATION=24h

backend/cmd/api/main.go

@@ -21,18 +21,8 @@
 //
 //	@tag.name system
 //	@tag.description System health and diagnostics
-//	@tag.name auth
-//	@tag.description Slack OAuth 2.0 authentication flow
-//	@tag.name users
-//	@tag.description User profile management
-//	@tag.name deep-work
-//	@tag.description Deep work session management
-//	@tag.name settings
-//	@tag.description User auto-reply configuration
-//	@tag.name logs
-//	@tag.description Auto-reply message history
 //	@tag.name slack
-//	@tag.description Slack Events API webhook
+//	@tag.description Slack authentication flow
 
 package main
 
@@ -49,7 +39,9 @@ import (
 	"github.com/kietle/zenreply/handler"
 	"github.com/kietle/zenreply/pkg/database"
 	"github.com/kietle/zenreply/pkg/logger"
+	"github.com/kietle/zenreply/pkg/slack"
 	"github.com/kietle/zenreply/route"
+	"github.com/kietle/zenreply/service"
 )
 
 func main() {
@@ -87,8 +79,12 @@ func main() {
 	}
 	log.Info("migrations applied successfully")
 
+	// --- Service ---
+	slackOAuth := slack.NewSlackOAuth(cfg)
+	authSvc := service.NewOAuthService(cfg, rdb, slackOAuth)
+
 	// --- Handler ---
-	h := handler.New(cfg, db, rdb)
+	h := handler.New(cfg, db, rdb, authSvc)
 
 	// --- HTTP Server ---
 	router := route.Setup(cfg, h, log)

backend/config/config.go

@@ -1,12 +1,10 @@
 package config
 
 import (
-	"log"
+	"fmt"
 	"os"
 	"strconv"
 	"time"
-
-	"github.com/joho/godotenv"
 )
 
 type AppConfig struct {
@@ -44,21 +42,22 @@ type RedisConfig struct {
 	URL      string
 }
 
+type SlackConfig struct {
+	ClientID      string
+	ClientSecret  string
+	SigningSecret string
+	RedirectURL   string
+}
+
 type Config struct {
 	App      AppConfig
 	Postgres PostgresConfig
 	Redis    RedisConfig
 	JWT      JWTConfig
+	Slack    SlackConfig
 }
 
 func Load() *Config {
-	if os.Getenv("ENV") == "development" {
-		err := godotenv.Load()
-		if err != nil {
-			log.Println(".env not found")
-		}
-	}
-
 	return &Config{
 		App: AppConfig{
 			Port:        getEnv("APP_PORT", "8080"),
@@ -72,7 +71,7 @@ func Load() *Config {
 			Port:     getEnv("POSTGRES_PORT", "5432"),
 			User:     getEnv("POSTGRES_USER", "postgres"),
 			Password: getEnv("POSTGRES_PASSWORD", "password"),
-			DB:       getEnv("POSTGRES_DB", "attendance_db"),
+			DB:       getEnv("POSTGRES_DB", "zenreply"),
 		},
 		Redis: RedisConfig{
 			Host:     getEnv("REDIS_HOST", "localhost"),
@@ -84,6 +83,12 @@ func Load() *Config {
 			Secret: getEnv("JWT_SECRET", "secret"),
 			Expiry: getEnvAsDuration("JWT_EXPIRY", 3600*time.Second),
 		},
+		Slack: SlackConfig{
+			ClientID:      getEnv("SLACK_CLIENT_ID", ""),
+			ClientSecret:  getEnv("SLACK_CLIENT_SECRET", ""),
+			SigningSecret: getEnv("SLACK_SIGNING_SECRET", ""),
+			RedirectURL:   fmt.Sprintf("%s/api/v1/slack/callback", getEnv("APP_BASE_URL", "https://localhost:8080")),
+		},
 	}
 }
 

backend/docs/docs.go

@@ -64,6 +64,47 @@ const docTemplate = `{
                     }
                 }
             }
+        },
+        "/slack/auth": {
+            "get": {
+                "description": "Generate a Slack OAuth URL for the user login",
+                "consumes": [
+                    "application/json"
+                ],
+                "produces": [
+                    "application/json"
+                ],
+                "tags": [
+                    "slack"
+                ],
+                "summary": "Generate Slack OAuth URL",
+                "responses": {
+                    "200": {
+                        "description": "OK",
+                        "schema": {
+                            "allOf": [
+                                {
+                                    "$ref": "#/definitions/github_com_kietle_zenreply_pkg_response.Response"
+                                },
+                                {
+                                    "type": "object",
+                                    "properties": {
+                                        "data": {
+                                            "$ref": "#/definitions/handler.SlackAuthURLResponse"
+                                        }
+                                    }
+                                }
+                            ]
+                        }
+                    },
+                    "500": {
+                        "description": "Internal Server Error",
+                        "schema": {
+                            "$ref": "#/definitions/github_com_kietle_zenreply_pkg_response.Response"
+                        }
+                    }
+                }
+            }
         }
     },
     "definitions": {
@@ -144,6 +185,19 @@ const docTemplate = `{
                     "example": "1.0.0"
                 }
             }
+        },
+        "handler.SlackAuthURLResponse": {
+            "type": "object",
+            "properties": {
+                "state": {
+                    "type": "string",
+                    "example": "123456"
+                },
+                "url": {
+                    "type": "string",
+                    "example": "https://slack.com/oauth/v2/authorize?client_id=1234567890\u0026scope=chat:write,im:write,channels:read,groups:read,users:read,reactions:read\u0026redirect_uri=https://localhost:8080/api/v1/slack/auth/callback"
+                }
+            }
         }
     },
     "securityDefinitions": {

backend/docs/swagger.json

@@ -62,6 +62,47 @@
                     }
                 }
             }
+        },
+        "/slack/auth": {
+            "get": {
+                "description": "Generate a Slack OAuth URL for the user login",
+                "consumes": [
+                    "application/json"
+                ],
+                "produces": [
+                    "application/json"
+                ],
+                "tags": [
+                    "slack"
+                ],
+                "summary": "Generate Slack OAuth URL",
+                "responses": {
+                    "200": {
+                        "description": "OK",
+                        "schema": {
+                            "allOf": [
+                                {
+                                    "$ref": "#/definitions/github_com_kietle_zenreply_pkg_response.Response"
+                                },
+                                {
+                                    "type": "object",
+                                    "properties": {
+                                        "data": {
+                                            "$ref": "#/definitions/handler.SlackAuthURLResponse"
+                                        }
+                                    }
+                                }
+                            ]
+                        }
+                    },
+                    "500": {
+                        "description": "Internal Server Error",
+                        "schema": {
+                            "$ref": "#/definitions/github_com_kietle_zenreply_pkg_response.Response"
+                        }
+                    }
+                }
+            }
         }
     },
     "definitions": {
@@ -142,6 +183,19 @@
                     "example": "1.0.0"
                 }
             }
+        },
+        "handler.SlackAuthURLResponse": {
+            "type": "object",
+            "properties": {
+                "state": {
+                    "type": "string",
+                    "example": "123456"
+                },
+                "url": {
+                    "type": "string",
+                    "example": "https://slack.com/oauth/v2/authorize?client_id=1234567890\u0026scope=chat:write,im:write,channels:read,groups:read,users:read,reactions:read\u0026redirect_uri=https://localhost:8080/api/v1/slack/auth/callback"
+                }
+            }
         }
     },
     "securityDefinitions": {

backend/docs/swagger.yaml

@@ -53,6 +53,15 @@ definitions:
         example: 1.0.0
         type: string
     type: object
+  handler.SlackAuthURLResponse:
+    properties:
+      state:
+        example: "123456"
+        type: string
+      url:
+        example: https://slack.com/oauth/v2/authorize?client_id=1234567890&scope=chat:write,im:write,channels:read,groups:read,users:read,reactions:read&redirect_uri=https://localhost:8080/api/v1/slack/auth/callback
+        type: string
+    type: object
 host: localhost:8080
 info:
   contact:
@@ -91,6 +100,30 @@ paths:
       summary: Health check
       tags:
       - system
+  /slack/auth:
+    get:
+      consumes:
+      - application/json
+      description: Generate a Slack OAuth URL for the user login
+      produces:
+      - application/json
+      responses:
+        "200":
+          description: OK
+          schema:
+            allOf:
+            - $ref: '#/definitions/github_com_kietle_zenreply_pkg_response.Response'
+            - properties:
+                data:
+                  $ref: '#/definitions/handler.SlackAuthURLResponse'
+              type: object
+        "500":
+          description: Internal Server Error
+          schema:
+            $ref: '#/definitions/github_com_kietle_zenreply_pkg_response.Response'
+      summary: Generate Slack OAuth URL
+      tags:
+      - slack
 schemes:
 - http
 - https

backend/go.mod

@@ -25,6 +25,7 @@ require (
 	github.com/go-playground/validator/v10 v10.30.1 // indirect
 	github.com/goccy/go-json v0.10.5 // indirect
 	github.com/goccy/go-yaml v1.19.2 // indirect
+	github.com/gorilla/websocket v1.5.3 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
@@ -58,6 +59,7 @@ require (
 	github.com/jackc/puddle/v2 v2.2.2 // indirect
 	github.com/joho/godotenv v1.5.1
 	github.com/redis/go-redis/v9 v9.18.0
+	github.com/slack-go/slack v0.20.0
 	github.com/swaggo/files v1.0.1
 	github.com/swaggo/gin-swagger v1.6.1
 	github.com/swaggo/swag v1.16.6

backend/go.sum

@@ -48,6 +48,8 @@ github.com/goccy/go-yaml v1.19.2/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7Lk
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
+github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
 github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
 github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=
@@ -91,6 +93,8 @@ github.com/quic-go/quic-go v0.59.0 h1:OLJkp1Mlm/aS7dpKgTc6cnpynnD2Xg7C1pwL6vy/SA
 github.com/quic-go/quic-go v0.59.0/go.mod h1:upnsH4Ju1YkqpLXC305eW3yDZ4NfnNbmQRCMWS58IKU=
 github.com/redis/go-redis/v9 v9.18.0 h1:pMkxYPkEbMPwRdenAzUNyFNrDgHx9U+DrBabWNfSRQs=
 github.com/redis/go-redis/v9 v9.18.0/go.mod h1:k3ufPphLU5YXwNTUcCRXGxUoF1fqxnhFQmscfkCoDA0=
+github.com/slack-go/slack v0.20.0 h1:gbDdbee8+Z2o+DWx05Spq3GzbrLLleiRwHUKs+hZLSU=
+github.com/slack-go/slack v0.20.0/go.mod h1:K81UmCivcYd/5Jmz8vLBfuyoZ3B4rQC2GHVXHteXiAE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=

backend/handler/handler.go

@@ -3,19 +3,22 @@ package handler
 import (
 	"github.com/jackc/pgx/v5/pgxpool"
 	"github.com/kietle/zenreply/config"
+	"github.com/kietle/zenreply/service"
 	"github.com/redis/go-redis/v9"
 )
 
 type Handler struct {
-	config *config.Config
-	db     *pgxpool.Pool
-	rdb    *redis.Client
+	config  *config.Config
+	db      *pgxpool.Pool
+	rdb     *redis.Client
+	authSvc *service.AuthService
 }
 
-func New(cfg *config.Config, db *pgxpool.Pool, rdb *redis.Client) *Handler {
+func New(cfg *config.Config, db *pgxpool.Pool, rdb *redis.Client, authSvc *service.AuthService) *Handler {
 	return &Handler{
-		config: cfg,
-		db:     db,
-		rdb:    rdb,
+		config:  cfg,
+		db:      db,
+		rdb:     rdb,
+		authSvc: authSvc,
 	}
 }