feat: add custom HTTP Email provider (#2542)

* feat: implement Custom HTTP Email provider

* Update Setting.js

* Update ProviderEditPage.js

* Update http.go

* Update provider.go

---------

Co-authored-by: hsluoyz <hsluoyz@qq.com>

email/http.go

@@ -0,0 +1,75 @@
+// Copyright 2023 The Casdoor Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package email
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+
+	"github.com/casdoor/casdoor/proxy"
+)
+
+type HttpEmailProvider struct {
+	endpoint string
+	method   string
+}
+
+func NewHttpEmailProvider(endpoint string, method string) *HttpEmailProvider {
+	client := &HttpEmailProvider{
+		endpoint: endpoint,
+		method:   method,
+	}
+	return client
+}
+
+func (c *HttpEmailProvider) Send(fromAddress string, fromName string, toAddress string, subject string, content string) error {
+	req, err := http.NewRequest(c.method, c.endpoint, bytes.NewBufferString(content))
+	if err != nil {
+		return err
+	}
+
+	if c.method == "POST" {
+		req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+		req.PostForm = map[string][]string{
+			"fromName":  {fromName},
+			"toAddress": {toAddress},
+			"subject":   {subject},
+			"content":   {content},
+		}
+	} else if c.method == "GET" {
+		q := req.URL.Query()
+		q.Add("fromName", fromName)
+		q.Add("toAddress", toAddress)
+		q.Add("subject", subject)
+		q.Add("content", content)
+		req.URL.RawQuery = q.Encode()
+	} else {
+		return fmt.Errorf("HttpEmailProvider's Send() error, unsupported method: %s", c.method)
+	}
+
+	httpClient := proxy.DefaultHttpClient
+	resp, err := httpClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("HttpEmailProvider's Send() error, custom HTTP Email request failed with status: %s", resp.Status)
+	}
+
+	return err
+}

email/provider.go

@@ -18,9 +18,11 @@ type EmailProvider interface {
 	Send(fromAddress string, fromName, toAddress string, subject string, content string) error
 }
 
-func GetEmailProvider(typ string, clientId string, clientSecret string, host string, port int, disableSsl bool) EmailProvider {
+func GetEmailProvider(typ string, clientId string, clientSecret string, host string, port int, disableSsl bool, endpoint string, method string) EmailProvider {
 	if typ == "Azure ACS" {
 		return NewAzureACSEmailProvider(clientSecret, host)
+	} else if typ == "Custom HTTP Email" {
+		return NewHttpEmailProvider(endpoint, method)
 	} else {
 		return NewSmtpEmailProvider(clientId, clientSecret, host, port, typ, disableSsl)
 	}