rob05c commented on a change in pull request #3023: WIP Supported routes fetch URL: https://github.com/apache/trafficcontrol/pull/3023#discussion_r233514672
########## File path: traffic_ops/traffic_ops_golang/api/api_route.go ########## @@ -0,0 +1,148 @@ +package api + +/* + * Licensed to the 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. The 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. + */ + +import "bytes" +import "net/http" +import "regexp" +import "strconv" +//import trops "github.com/apache/trafficcontrol/traffic_ops/traffic_ops_golang" +import log "github.com/apache/trafficcontrol/lib/go-log" + +// todo - make the version string modular and accessible everywhere +const ServerString = "Traffic Operations/3.0.0"; +const errorString = "Check the Traffic Ops log file(s) for details\n"; + +var APIVersions []float64; + + +// CompiledRoute ... +type CompiledRoute struct { + Handler http.HandlerFunc + Regex *regexp.Regexp + Params []string +} + + +var AllRoutes *map[string][]CompiledRoute; +// Writes a message indicating an internal server error back to the client (in plain text) +func errorResponse(writer http.ResponseWriter) { + err := []byte(errorString); + writer.Header().Set("Content-Length", strconv.Itoa(len(err))); + writer.WriteHeader(http.StatusInternalServerError); + writer.Write(err); +} + +// Handles the disallowed request methods for this endpoint +func AvailableRoutesBadMethodHandler(writer http.ResponseWriter, request *http.Request) { + writer.Header().Set("Allow", "OPTIONS"); + writer.Header().Set("Server", ServerString); + writer.WriteHeader(http.StatusMethodNotAllowed); +} + +func AvailableVersionsHandler(writer http.ResponseWriter, request *http.Request) { + writer.Header().Set("Server", ServerString); + + // check that this has been set + if APIVersions == nil { + writer.Header().Set("Content-Length", "0"); + writer.WriteHeader(http.StatusNoContent); + return; + } + + writer.Header().Set("Content-Type", "text/plain; charset=utf-8"); + + var body bytes.Buffer; + contentLength := 0; + for _, version := range APIVersions { + n, err := body.WriteString(strconv.FormatFloat(version, 'f', 1, 64)); + if err != nil { + log.Errorf("Unable to append API version to buffer: %s", err.Error()); + errorResponse(writer); + return; + } + contentLength += n; + body.WriteRune('\n'); + contentLength += 1; + } + + writer.Header().Set("Content-Length", strconv.Itoa(contentLength)); + writer.WriteHeader(http.StatusOK); + writer.Write(body.Bytes()); + log.Infof("API versions: '%s'", body.String()) +} + +// Writes a list of all available API routes in a response to the client in plaintext +// (or writes an error message via errorResponse if something wicked happens) +func AvailableRoutesHandler(writer http.ResponseWriter, request *http.Request) { + writer.Header().Set("Server", ServerString); + + // Check for a CORS preflight request (all headers accepted, so immediate response given) + if request.Header.Get("Origin") != "" && + request.Header.Get("Access-Control-Request-Method") != "" && + request.Header.Get("Access-Control-Request-Headers") != "" { + + writer.Header().Set("Access-Control-Allow-Methods", "OPTIONS,GET"); + writer.Header().Set("Access-Control-Allow-Headers", "*"); + writer.WriteHeader(http.StatusNoContent); + return; + } + + // ... otherwise, return a list of all supported methods/routes + + // if for some reason the variable didn't get set properly, return nothing + if AllRoutes == nil { + writer.Header().Set("Content-Length", "0"); + writer.Header().Set("Allow", "OPTIONS,GET"); + writer.WriteHeader(http.StatusNoContent); Review comment: >if this code were accessed before the routes were set/generated this would be the proper behaviour The routes are "set" before TO starts serving HTTP, that isn't possible. Even if it was, it's still a server error, should be a 503 in that case. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
