| // Licensed to Apache Software Foundation (ASF) under one or more contributor |
| // license agreements. See the NOTICE file distributed with |
| // this work for additional information regarding copyright |
| // ownership. Apache Software Foundation (ASF) licenses this file to you 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 mux |
| |
| import ( |
| "fmt" |
| "net/http" |
| |
| "github.com/apache/skywalking-go/plugins/core/operator" |
| "github.com/apache/skywalking-go/plugins/core/tracing" |
| ) |
| |
| type ServeHTTPInterceptor struct { |
| } |
| |
| func (n *ServeHTTPInterceptor) BeforeInvoke(invocation operator.Invocation) error { |
| request := invocation.Args()[1].(*http.Request) |
| s, err := tracing.CreateEntrySpan(fmt.Sprintf("%s:%s", request.Method, request.RequestURI), func(headerKey string) (string, error) { |
| return request.Header.Get(headerKey), nil |
| }, tracing.WithLayer(tracing.SpanLayerHTTP), |
| tracing.WithComponent(5017), |
| tracing.WithTag(tracing.TagHTTPMethod, request.Method), |
| tracing.WithTag(tracing.TagURL, request.Host+request.URL.Path)) |
| if err != nil { |
| return err |
| } |
| |
| writer := invocation.Args()[0].(http.ResponseWriter) |
| invocation.ChangeArg(0, &writerWrapper{ResponseWriter: writer, statusCode: http.StatusOK}) |
| invocation.SetContext(s) |
| return nil |
| } |
| |
| func (n *ServeHTTPInterceptor) AfterInvoke(invocation operator.Invocation, results ...interface{}) error { |
| if invocation.GetContext() == nil { |
| return nil |
| } |
| span := invocation.GetContext().(tracing.Span) |
| if wrapped, ok := invocation.Args()[0].(*writerWrapper); ok { |
| span.Tag(tracing.TagStatusCode, fmt.Sprintf("%d", wrapped.statusCode)) |
| } |
| span.End() |
| return nil |
| } |
| |
| type writerWrapper struct { |
| http.ResponseWriter |
| statusCode int |
| } |
| |
| func (w *writerWrapper) WriteHeader(statusCode int) { |
| // cache the status code |
| w.statusCode = statusCode |
| w.ResponseWriter.WriteHeader(statusCode) |
| } |