add x/errors.OK, Create, NoContent and NoContentOrNotModified package-level generic functions as custom service helpers

_examples/README.md

@@ -55,6 +55,7 @@
     * [Custom HTTP Errors](routing/http-errors/main.go)
     * [HTTP Wire Errors](routing/http-wire-errors/main.go) **NEW**
         * [Custom Validation Errors](routing/http-wire-errors/custom-validation-errors/main.go)
+        * [Service](routing/http-wire-errors/service/main.go) **NEW**
     * [Not Found - Intelligence](routing/intelligence/main.go)
         * [Not Found - Suggest Closest Paths](routing/intelligence/manual/main.go)
     * [Dynamic Path](routing/dynamic-path/main.go)

_examples/routing/http-wire-errors/main.go

@@ -29,7 +29,7 @@ import (
 // errors.Unavailable
 // errors.DataLoss
 var (
-	Custom = errors.E("CUSTOM_CANONICAL_ERROR_NAME", iris.StatusBadRequest)
+	Custom = errors.Register("CUSTOM_CANONICAL_ERROR_NAME", iris.StatusBadRequest)
 )
 
 func main() {

_examples/routing/http-wire-errors/service/main.go

@@ -0,0 +1,127 @@
+package main
+
+import (
+	"context"
+	"strings"
+
+	"github.com/kataras/iris/v12"
+	"github.com/kataras/iris/v12/x/errors"
+)
+
+func main() {
+	app := iris.New()
+
+	service := new(myService)
+	app.Post("/", createHandler(service))
+	app.Get("/", listHandler(service))
+	app.Delete("/{id:string}", deleteHandler(service))
+
+	app.Listen(":8080")
+}
+
+func createHandler(service *myService) iris.Handler {
+	return func(ctx iris.Context) {
+		// What it does?
+		// 1. Reads the request body and binds it to the CreateRequest struct.
+		// 2. Calls the service.Create function with the given request body.
+		// 3. If the service.Create returns an error, it sends an appropriate error response to the client.
+		// 4. If the service.Create returns a response, it sets the status code to 201 (Created) and sends the response as a JSON payload to the client.
+		//
+		// Useful for create operations.
+		errors.Create(ctx, service.Create)
+	}
+}
+
+func listHandler(service *myService) iris.Handler {
+	return func(ctx iris.Context) {
+		// What it does?
+		// 1. If the 3rd variadic (optional) parameter is empty (not our case here), it reads the request body and binds it to the ListRequest struct,
+		// otherwise (our case) it calls the service.List function directly with the given input parameter (empty ListRequest struct value in our case).
+		// 2. Calls the service.List function with the ListRequest value.
+		// 3. If the service.List returns an error, it sends an appropriate error response to the client.
+		// 4. If the service.List returns a response, it sets the status code to 200 (OK) and sends the response as a JSON payload to the client.
+		//
+		// Useful for get single, fetch multiple and search operations.
+		errors.OK(ctx, service.List, ListRequest{})
+	}
+}
+
+func deleteHandler(service *myService) iris.Handler {
+	return func(ctx iris.Context) {
+		id := ctx.Params().Get("id")
+		// What it does?
+		// 1. Calls the service.Delete function with the given input parameter.
+		// 2. If the service.Delete returns an error, it sends an appropriate error response to the client.
+		// 3.If the service.Delete doesn't return an error then it sets the status code to 204 (No Content) and
+		// sends the response as a JSON payload to the client.
+		// errors.NoContent(ctx, service.Delete, id)
+		// OR:
+		// 1. Calls the service.DeleteWithFeedback function with the given input parameter.
+		// 2. If the service.DeleteWithFeedback returns an error, it sends an appropriate error response to the client.
+		// 3. If the service.DeleteWithFeedback returns true, it sets the status code to 204 (No Content).
+		// 4. If the service.DeleteWithFeedback returns false, it sets the status code to 304 (Not Modified).
+		//
+		// Useful for update and delete operations.
+		errors.NoContentOrNotModified(ctx, service.DeleteWithFeedback, id)
+	}
+}
+
+type (
+	myService struct{}
+
+	CreateRequest struct {
+		Fullname string
+	}
+
+	CreateResponse struct {
+		ID        string
+		Firstname string
+		Lastname  string
+	}
+)
+
+func (s *myService) Create(ctx context.Context, in CreateRequest) (CreateResponse, error) {
+	arr := strings.Split(in.Fullname, " ")
+	firstname, lastname := arr[0], arr[1]
+	id := "test_id"
+
+	resp := CreateResponse{
+		ID:        id,
+		Firstname: firstname,
+		Lastname:  lastname,
+	}
+	return resp, nil // , errors.New("create: test error")
+}
+
+type ListRequest struct {
+}
+
+func (s *myService) List(ctx context.Context, in ListRequest) ([]CreateResponse, error) {
+	resp := []CreateResponse{
+		{
+			ID:        "test-id-1",
+			Firstname: "test first name 1",
+			Lastname:  "test last name 1",
+		},
+		{
+			ID:        "test-id-2",
+			Firstname: "test first name 2",
+			Lastname:  "test last name 2",
+		},
+		{
+			ID:        "test-id-3",
+			Firstname: "test first name 3",
+			Lastname:  "test last name 3",
+		},
+	}
+
+	return resp, nil //, errors.New("list: test error")
+}
+
+func (s *myService) Delete(ctx context.Context, id string) error {
+	return nil // errors.New("delete: test error")
+}
+
+func (s *myService) DeleteWithFeedback(ctx context.Context, id string) (bool, error) {
+	return true, nil // false, errors.New("delete: test error")
+}