feat: add errno

README.md

@@ -126,3 +126,11 @@ Set up the web server with some necessary/nice to have middlewares.
 - RequestId
 
 Using channel and signal to gracefully shutdown the server.
+
+A more comprehensible error code design :
+
+- Classical HTTP code.
+- Service error code composed by "PlatformError.ServiceError", e.g. "ResourceNotFound.PageNotFound"
+- error message.
+
+The service error code helps to identify the problem more precisely.

internal/howmuch/howmuch.go

@@ -31,6 +31,8 @@ import (
 	"syscall"
 	"time"
 
+	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/core"
+	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/errno"
 	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/log"
 	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/middleware"
 	"git.vinchent.xyz/vinchent/howmuch/pkg/version/verflag"
@@ -112,9 +114,13 @@ func run() error {
 
 	r.Use(middleware.RequestID())
 
+	r.NoRoute(func(ctx *gin.Context) {
+		core.WriteResponse(ctx, errno.PageNotFoundErr, nil)
+	})
+
 	r.GET("/", func(ctx *gin.Context) {
 		// time.Sleep(10 * time.Second) // Test shutdown
-		ctx.JSON(http.StatusOK, gin.H{
+		core.WriteResponse(ctx, nil, gin.H{
 			"message": "how much?",
 		})
 	})

internal/pkg/core/core.go

@@ -0,0 +1,51 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package core
+
+import (
+	"net/http"
+
+	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/errno"
+	"github.com/gin-gonic/gin"
+)
+
+type ErrResponse struct {
+	Code    string `json:"code"`
+	Message string `json:"message"`
+}
+
+// WriteResponse writes the response to the HTTP response writer with HTTP code
+// and potential errors.
+func WriteResponse(c *gin.Context, err error, data any) {
+	// No error, write json response directly
+	if err == nil {
+		c.JSON(http.StatusOK, data)
+		return
+	}
+
+	error := errno.Decode(err)
+	c.JSON(error.HTTP, ErrResponse{
+		Code:    error.Code,
+		Message: error.Message,
+	})
+}

internal/pkg/errno/code.go

@@ -0,0 +1,41 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package errno
+
+import "net/http"
+
+var (
+	OK = &Errno{HTTP: http.StatusOK, Code: "", Message: ""}
+
+	InternalServerErr = &Errno{
+		HTTP:    http.StatusInternalServerError,
+		Code:    "InternalError",
+		Message: "Internal server error",
+	}
+
+	PageNotFoundErr = &Errno{
+		HTTP:    http.StatusNotFound,
+		Code:    "ResourceNotFound.PageNotFound",
+		Message: "Page not found",
+	}
+)

internal/pkg/errno/errno.go

@@ -0,0 +1,51 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package errno
+
+type Errno struct {
+	HTTP    int
+	Code    string
+	Message string
+}
+
+// Error implements Error() method in error interface
+func (err *Errno) Error() string {
+	return err.Message
+}
+
+// Decode tries to get the Errno from the error
+func Decode(err error) *Errno {
+	if err == nil {
+		return OK
+	}
+
+	switch typed := err.(type) {
+	case *Errno:
+		return typed
+	default:
+	}
+
+	internErr := InternalServerErr
+	internErr.Message = err.Error()
+	return internErr
+}