--- /dev/null
+// vi: ts=4 sw=4 noet:
+/*
+==================================================================================
+ Copyright (c) 2022 Alexandre Huff
+
+ 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.
+==================================================================================
+*/
+
+/*
+ Mnemonic: restclient.cpp
+ Abstract: Implements a tiny wrapper on top of libcurl to handle with rest requests.
+
+ Date: 8 Apr 2022
+ Author: Alexandre Huff
+*/
+
+
+#include "restclient.hpp"
+#include <mutex>
+#include <string.h>
+#include <memory>
+
+namespace restclient {
+
+// callback to handle http responses
+static size_t http_response_callback( const char *in, size_t size, size_t num, std::string *out ) {
+ if( out == NULL ) {
+ return 0;
+ }
+ const size_t totalBytes( size * num );
+ out->append( in, totalBytes );
+ return totalBytes;
+}
+
+/*
+ Create a RestClient instance to exchange messages with
+ a given rest api available on baseUrl, which consists of
+ scheme://domain[:port]
+*/
+RestClient::RestClient( std::string baseUrl ) {
+ this->baseUrl = baseUrl;
+
+ if( ! init() ) {
+ fprintf( stderr, "unable to initialize RestClient\n" );
+ }
+}
+
+RestClient::~RestClient( ) {
+ curl_slist_free_all( headers );
+ curl_easy_cleanup( curl );
+}
+
+std::string RestClient::getBaseUrl( ) {
+ return baseUrl;
+}
+
+bool RestClient::init( ) {
+ static std::mutex curl_mutex;
+
+ { // scoped mutex to make curl_global_init thread-safe
+ const std::lock_guard<std::mutex> lock( curl_mutex );
+ curl_global_init( CURL_GLOBAL_DEFAULT );
+ }
+
+ curl = curl_easy_init();
+ if( curl == NULL ) {
+ return false;
+ }
+
+ // curl_easy_setopt( curl, CURLOPT_VERBOSE, 1L );
+ curl_easy_setopt( curl, CURLOPT_TIMEOUT, 5 );
+
+ /* provide a buffer to store errors in */
+ if( curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errbuf) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_ERRORBUFFER\n" );
+ return false;
+ }
+ errbuf[0] = 0;
+
+ if( curl_easy_setopt( curl, CURLOPT_WRITEFUNCTION, http_response_callback ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_WRITEFUNCTION\n" );
+ return false;
+ }
+
+ if( curl_easy_setopt( curl, CURLOPT_WRITEDATA, &response.body ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_WRITEDATA\n" );
+ return false;
+ }
+
+ headers = curl_slist_append( headers, "Accept: application/json" );
+ headers = curl_slist_append( headers, "Content-Type: application/json" );
+ if( curl_easy_setopt( curl, CURLOPT_HTTPHEADER, headers ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_HTTPHEADER\n" );
+ return false;
+ }
+
+ return true;
+}
+
+/*
+ Executes a GET request at the path of this RestClient instance.
+ Returns the HTTP status code and the correspoding message body.
+*/
+response_t RestClient::do_get( std::string path ) {
+ response = { 0, "" };
+
+ const std::string endpoint = baseUrl + path;
+
+ if( curl_easy_setopt( curl, CURLOPT_URL, endpoint.c_str() ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_URL\n" );
+ return response;
+ }
+ if( curl_easy_setopt( curl, CURLOPT_HTTPGET, 1L ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_HTTPGET\n" );
+ return response;
+ }
+
+ CURLcode res = curl_easy_perform( curl );
+ if( res == CURLE_OK ) {
+ if( curl_easy_getinfo( curl, CURLINFO_RESPONSE_CODE, &response.status_code ) != CURLE_OK ) {
+ fprintf( stderr, "unable to get CURLINFO_RESPONSE_CODE\n" );
+ }
+ } else {
+ size_t len = strlen( errbuf );
+ fprintf( stderr, "unable to complete the request url=%s ", endpoint.c_str() );
+ if(len)
+ fprintf( stderr, "error=%s%s", errbuf,
+ ( ( errbuf[len - 1] != '\n' ) ? "\n" : "") );
+ else
+ fprintf( stderr, "error=%s\n", curl_easy_strerror( res ) );
+ }
+
+ return response;
+}
+
+/*
+ Executes a POST request of a json message at the path of this RestClient instance.
+ Returns the HTTP status code and the correspoding message body.
+*/
+response_t RestClient::do_post( std::string path, std::string json ) {
+ response = { 0, "" };
+
+ const std::string endpoint = baseUrl + path;
+
+ if( curl_easy_setopt( curl, CURLOPT_URL, endpoint.c_str() ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_URL\n" );
+ return response;
+ }
+ if( curl_easy_setopt( curl, CURLOPT_POST, 1L ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_POST\n" );
+ return response;
+ }
+ if( curl_easy_setopt( curl, CURLOPT_POSTFIELDS, json.c_str() ) != CURLE_OK ) {
+ fprintf( stderr, "unable to set CURLOPT_POSTFIELDS\n" );
+ return response;
+ }
+
+ CURLcode res = curl_easy_perform( curl );
+ if( res == CURLE_OK ) {
+ if( curl_easy_getinfo( curl, CURLINFO_RESPONSE_CODE, &response.status_code ) != CURLE_OK ) {
+ fprintf( stderr, "unable to get CURLINFO_RESPONSE_CODE\n" );
+ }
+ } else {
+ size_t len = strlen( errbuf );
+ fprintf( stderr, "unable to complete the request url=%s ", endpoint.c_str() );
+ if(len)
+ fprintf( stderr, "error=%s%s", errbuf,
+ ( (errbuf[len - 1] != '\n' ) ? "\n" : "") );
+ else
+ fprintf( stderr, "error=%s\n", curl_easy_strerror( res ) );
+ }
+
+ return response;
+}
+
+} // namespace
Code Review / ric-app / ts.git / blobdiff