request parser rewrite + added tests

* rewrote request parser, now more simplified and theoretically faster
* added gtest and an example test to measure parser times

CMakeLists.txt

@@ -15,7 +15,7 @@ add_custom_target(build-version
 
 add_custom_target(build-supplemental 
     COMMAND cd ../build_supp && python3 ./error_gen.py
-    COMMAND mkdir www && cp -r ../default_www/regular/* ./www/
+    COMMAND mkdir -p www && cp -r ../default_www/regular/* ./www/
     DEPENDS build_supp/version.txt ../default_www/regular/* build_supp/error_gen.py build-version
     COMMENT "Generated supplemental build files (default www dir + error pages)"
 )
@@ -38,3 +38,38 @@ add_dependencies(anthracite-bin anthracite)
 add_executable(anthracite-api-bin src/api_main.cpp) 
 target_link_libraries(anthracite-api-bin anthracite)
 
+include(FetchContent)
+FetchContent_Declare(
+  googletest
+  URL https://github.com/google/googletest/archive/03597a01ee50ed33e9dfd640b249b4be3799d395.zip
+)
+
+FetchContent_MakeAvailable(googletest)
+
+file(GLOB TESTS_SRC CONFIGURE_DEPENDS "tests/*.cpp")
+enable_testing()
+
+add_custom_target(test_files
+    COMMAND cp -r ../tests/test_files . 
+    DEPENDS ../tests/test_files/* 
+    COMMENT "Copied test resource files"
+)
+
+add_executable(
+  tests
+  ${TESTS_SRC}
+)
+add_dependencies(tests anthracite)
+add_dependencies(tests test_files)
+
+target_link_libraries(
+  tests
+  GTest::gtest_main
+)
+target_link_libraries(
+  tests
+  anthracite
+)
+
+include(GoogleTest)
+gtest_discover_tests(tests)

lib/http/request.cpp

@@ -5,115 +5,109 @@
 
 namespace anthracite::http {
 
+void request::parse_header(std::string& raw_line) {
+    auto delim_pos = raw_line.find_first_of(':');
+    auto value_pos = raw_line.find_first_not_of(' ', delim_pos+1);
+
+    std::string header_name = raw_line.substr(0,delim_pos);
+    std::string header_val = raw_line.substr(value_pos);
+
+    _headers[header_name] = header(header_name, header_val);
+}
+
+void request::parse_query_param(std::string& raw_param) {
+    auto delim_pos = raw_param.find_first_of('=');
+    auto value_pos = delim_pos+1;
+
+    std::string query_name = raw_param.substr(0,delim_pos);
+    std::string query_val = raw_param.substr(value_pos);
+
+    _query_params[query_name] = query_param(query_name, query_val);
+}
+
+void request::parse_path(std::string& raw_path) {
+    std::stringstream ss(raw_path);
+    std::string tok;
+
+    if (getline(ss, tok, '?')){
+        _path = tok;
+    }
+    
+    while(getline(ss, tok, '&')) {
+        parse_query_param(tok);
+    }
+}
+
+void request::parse_request_line(std::string& raw_line) {
+        request_line_parser_state state = METHOD;
+        std::stringstream ss(raw_line);
+        std::string tok;
+        while(getline(ss, tok, ' ')){
+            switch(state) {
+                case METHOD: {
+                    auto search = method_map.find(tok);
+                    if (search != method_map.end()) {
+                        _method = search->second;
+                    } else {
+                        _method = method::UNKNOWN;
+                    }
+
+                    state = PATH;
+                    break;
+                };
+                
+                case PATH: {
+                    parse_path(tok);
+                    state = VERSION;
+                    break;
+                };
+
+                case VERSION: {
+                    auto search = version_map.find(tok);
+                    if (search != version_map.end()) {
+                        _http_version = search->second;
+                    } else {
+                        _http_version = version::HTTP_1_0;
+                    }
+                    return;
+                };
+            }
+        }
+}
+
 request::request(std::string& raw_data, const std::string& client_ip)
     : _path("")
     , _client_ipaddr(client_ip)
 {
 
-    parser_state state = METHOD;
+    parser_state state = REQUEST_LINE;
 
-    std::string scratch = "";
-    std::string scratch_2 = "";
-    for (int i = 0; i < raw_data.length(); i++) {
-        switch (state) {
-        case METHOD: {
-            if (raw_data[i] == ' ') {
-                if (method_map.find(scratch) == method_map.end()) {
-                    _method = method::UNKNOWN;
+    std::stringstream line_stream(raw_data);
+    std::string line;
+
+    while(getline(line_stream, line, '\n') && state != BODY_CONTENT){
+        line.pop_back(); // HTTP requests do newline as \r\n, this removes the \r 
+        switch(state) {
+            case REQUEST_LINE: {
+                                   parse_request_line(line); 
+                                   state = HEADERS;
+                                   break;
+                               };
+            case HEADERS: {
+                if (line.length() == 0) {
+                    state = BODY_CONTENT;
                 } else {
-                    _method = method_map.find(scratch)->second;
+                    parse_header(line); 
                 }
-                scratch = "";
-                state = PATH;
-            } else {
-                scratch += raw_data[i];
-            }
-        } break;
-
-        case PATH: {
-            switch (raw_data[i]) {
-            case ' ':
-                state = VERSION;
                 break;
-            case '?':
-                state = QUERY_PARAM_NAME;
-                break;
-            default:
-                _path += raw_data[i];
-                break;
-            }
-        } break;
-
-        case QUERY_PARAM_NAME: {
-            if (raw_data[i] == ' ') {
-                scratch = "";
-                state = VERSION;
-            } else if (raw_data[i] == '=') {
-                state = QUERY_PARAM_VALUE;
-            } else {
-                scratch += raw_data[i];
-            }
-        } break;
-
-        case QUERY_PARAM_VALUE: {
-            if (raw_data[i] == ' ') {
-                _query_params[scratch] = query_param(scratch, scratch_2);
-                scratch = "";
-                scratch_2 = "";
-                state = VERSION;
-            } else if (raw_data[i] == '&') {
-                _query_params[scratch] = query_param(scratch, scratch_2);
-                scratch = "";
-                scratch_2 = "";
-                state = QUERY_PARAM_NAME;
-            } else {
-                scratch_2 += raw_data[i];
-            }
-        } break;
-
-        case VERSION: {
-            if (raw_data[i] == '\n') {
-                _http_version = version_map.find(scratch)->second;
-                scratch = "";
-                state = HEADER_NAME;
-            } else if (raw_data[i] != '\r') {
-                scratch += raw_data[i];
-            }
-        } break;
-
-        case HEADER_NAME: {
-            if (raw_data[i] == '\n') {
-                scratch = "";
-                scratch_2 = "";
-                state = BODY_CONTENT;
-                break;
-            } else if (raw_data[i] == ' ') {
-                scratch = "";
-                break;
-            } else if (raw_data[i] == ':') {
-                state = HEADER_VALUE;
-                i++;
-            } else {
-                scratch += raw_data[i];
-            }
-        } break;
-
-        case HEADER_VALUE: {
-            if (raw_data[i] == '\n') {
-                _headers[scratch] = header(scratch, scratch_2);
-                scratch = "";
-                scratch_2 = "";
-                state = HEADER_NAME;
-            } else if (raw_data[i] != '\r') {
-                scratch_2 += raw_data[i];
-            }
-        } break;
-
-        case BODY_CONTENT: {
-            _body_content += raw_data[i];
-        } break;
+            };
+            case BODY_CONTENT: break;
         }
     }
+
+    if (getline(line_stream, line, '\0')) {
+        _body_content = line;
+    }
 }
 
 std::string request::path() { return _path; }
@@ -129,7 +123,6 @@ version request::get_http_version()
 
 bool request::is_supported_version()
 {
-    // log::err << reverse_version_map.find(_http_version)->second << std::endl;
     return _http_version == HTTP_1_1 || _http_version == HTTP_1_0;
 }
 

lib/http/request.hpp

@@ -9,14 +9,16 @@ namespace anthracite::http {
 
 class request {
 private:
-    enum parser_state { METHOD,
-        PATH,
-        QUERY_PARAM_NAME,
-        QUERY_PARAM_VALUE,
-        VERSION,
-        HEADER_NAME,
-        HEADER_VALUE,
-        BODY_CONTENT };
+    enum request_line_parser_state {
+        METHOD, PATH, VERSION
+    };
+
+    enum parser_state {
+        REQUEST_LINE,
+        HEADERS,
+        BODY_CONTENT
+    };
+
     method _method;
     version _http_version;
     std::string _path;
@@ -24,6 +26,11 @@ private:
     std::string _body_content;
     std::unordered_map<std::string, header> _headers; // kinda goofy, whatever
     std::unordered_map<std::string, query_param> _query_params; // kinda goofy, whatever
+                                                                //
+    void parse_request_line(std::string& raw_line);
+    void parse_header(std::string& raw_line);
+    void parse_path(std::string& raw_path);
+    void parse_query_param(std::string& raw_param);
 
 public:
     request(std::string& raw_data, const std::string& client_ip);

tests/speed_tests.cpp

@@ -0,0 +1,28 @@
+#include <gtest/gtest.h>
+#include <fstream>
+#include <chrono>
+#include "../lib/http/request.hpp"
+
+
+TEST(speed_tests, request_parse) {
+    using std::chrono::high_resolution_clock;
+    using std::chrono::duration_cast;
+    using std::chrono::duration;
+    using std::chrono::milliseconds;
+
+    std::ifstream t("./test_files/test_request.http");
+    std::stringstream buffer;
+    buffer << t.rdbuf();
+    std::string raw_req = buffer.str();
+
+    auto t1 = high_resolution_clock::now();
+    for(int i = 0; i < 1000000; ++i) {
+        volatile anthracite::http::request req (raw_req, "0.0.0.0");
+    }
+    auto t2 = high_resolution_clock::now();
+
+    /* Getting number of milliseconds as an integer. */
+    auto ms_int = duration_cast<milliseconds>(t2 - t1);
+
+    std::cout << "Parsed 1 Million requests in " << ms_int << "ms" << std::endl;
+}

tests/test_files/test_request.http

@@ -0,0 +1,13 @@
+GET /foo/bar?test=a&test2=b HTTP/1.1
+Host: example.org
+User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; fr; rv:1.9.2.8) Gecko/20100722 Firefox/3.6.8
+Accept: */*
+Accept-Language: fr,fr-fr;q=0.8,en-us;q=0.5,en;q=0.3
+Accept-Encoding: gzip,deflate
+Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
+Keep-Alive: 115
+Connection: keep-alive
+Content-Type: application/x-www-form-urlencoded
+X-Requested-With: XMLHttpRequest
+Referer: http://example.org/test
+Cookie: foo=bar; lorem=ipsum;