83 lines
2.1 KiB
Go
83 lines
2.1 KiB
Go
package middleware
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/*
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* Copyright 2024 Jonas Kaninda
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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*/
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import (
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"bytes"
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"encoding/json"
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"github.com/jkaninda/goma-gateway/pkg/logger"
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"io"
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"net/http"
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)
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func newResponseRecorder(w http.ResponseWriter) *responseRecorder {
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return &responseRecorder{
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ResponseWriter: w,
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statusCode: http.StatusOK,
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body: &bytes.Buffer{},
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}
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}
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func (rec *responseRecorder) WriteHeader(code int) {
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rec.statusCode = code
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}
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func (rec *responseRecorder) Write(data []byte) (int, error) {
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return rec.body.Write(data)
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}
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// ErrorInterceptor Middleware intercepts backend errors
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func (intercept InterceptErrors) ErrorInterceptor(next http.Handler) http.Handler {
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return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
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rec := newResponseRecorder(w)
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next.ServeHTTP(rec, r)
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if canIntercept(rec.statusCode, intercept.Errors) {
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logger.Error("Backend error")
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logger.Error("An error occurred from the backend with the status code: %d", rec.statusCode)
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w.Header().Set("Content-Type", "application/json")
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w.WriteHeader(rec.statusCode)
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err := json.NewEncoder(w).Encode(ProxyResponseError{
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Success: false,
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Code: rec.statusCode,
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Message: http.StatusText(rec.statusCode),
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})
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if err != nil {
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return
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}
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} else {
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// No error: write buffered response to client
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w.WriteHeader(rec.statusCode)
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_, err := io.Copy(w, rec.body)
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if err != nil {
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return
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}
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}
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})
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}
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func canIntercept(code int, errors []int) bool {
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for _, er := range errors {
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if er == code {
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return true
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}
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continue
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}
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return false
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}
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