A RequestParser that builds a request from interrupted input from a Stream

src/RequestParser.cpp

@@ -0,0 +1,81 @@
+#include "RequestParser.h"
+
+bool RequestParser::parse() {
+
+    while (client.available() && _state != S_ERROR) {
+        char in = client.read();
+
+        switch (_state) {
+            case S_IN_METHOD:
+                if (in == ' ') {
+                    *(_i++) = '\0';
+                    request.setMethod(_buffer);
+                    _i = _buffer;
+                    _state = S_IN_URL;
+                    break;
+                }
+                *(_i++) = in;
+                break;
+            case S_IN_URL:
+                // skip preceding whitespace
+                if (in == ' ') {
+                    if (_i == _buffer) continue;
+                    *(_i) = '\0';
+                    request.setUrl(_buffer);
+                    _i = _buffer;
+                    _state = S_IN_HTTPVER;
+                    break;
+                }
+                *(_i++) = in;
+                break;
+            case S_IN_HTTPVER:
+                if (in == '\r') continue;
+                if (in == '\n') {
+                    *(_i) = '\0';
+                    request.setHttpVer(_buffer);
+                    _i = _buffer;
+                    _state = S_IN_HEADER;
+                    break;
+                }
+                *(_i++) = in;
+                break;
+            case S_IN_HEADER:
+                if (in == '\r') continue;
+                if (in == '\n') {
+                    if (_i == _buffer) {
+                        if (request.headers.has("Content-Length"))
+                            _state = S_IN_MESSAGE;
+                        else _state = S_COMPLETE;
+                        break;
+                    }
+                    char * name = _buffer;
+                    char * value = _buffer;
+                    bool s = 0;
+                    while (value < _i) {
+                        if (s) {
+                            if (*value == ' ') value++;
+                            else break;
+                        } else {
+                            if (*value == ':') {
+                                s = true;
+                                *(value++) = '\0';
+                            } else value++;
+                        }
+                    }
+                    request.headers.set(name, value);
+                    _i = _buffer;
+                    break;
+                }
+                *(_i++) = in;
+                break;
+            case S_COMPLETE:
+                return true;
+            default:
+                _state = S_ERROR;
+
+        }
+
+    }
+
+    return (_state == S_COMPLETE || _state == S_ERROR);
+}

src/RequestParser.h

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+#pragma once
+#include "HttpRequest.h"
+#include "Arduino.h"
+
+#ifndef REQUESTPARSER_BUFFER
+#define REQUESTPARSER_BUFFER 512
+#endif
+
+enum RequestParserState {
+    S_IN_METHOD,
+    S_IN_URL,
+    S_IN_HTTPVER,
+    S_IN_HEADER,
+    S_IN_MESSAGE,
+    S_COMPLETE,
+    S_ERROR
+};
+    
+class RequestParser
+{
+    public:
+        RequestParser(HttpRequest& req, Stream& client):
+            request(req),
+            client(client),
+            _state(S_IN_METHOD)
+            {};
+
+        bool parse();
+        bool error() { return _state == S_ERROR; };
+        
+
+    private:
+        char _buffer[REQUESTPARSER_BUFFER] = {};
+        char * _i = _buffer;
+        HttpRequest& request;
+        Stream& client;
+        RequestParserState _state;
+};

test/test_RequestParser.cpp

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+#include "catch.hpp"
+#include "Buffer.h"
+#include "RequestParser.h"
+using Catch::Matchers::Equals;
+
+TEST_CASE("Test GET","[RequestParser]")
+{
+    uint8_t _buff[256] = {};
+    Buffer client(_buff, 256);
+    HttpRequest request;
+    RequestParser parser(request, client);
+
+    client.write("GET ");
+    CHECK(parser.parse() == 0);
+    CHECK_THAT(request.getMethod(), Equals("GET"));
+
+    client.write("/foo ");
+    CHECK(parser.parse() == 0);
+    CHECK_THAT(request.getUrl(), Equals("/foo"));
+
+    client.write("HTTP/1.1\r\n");
+    CHECK(parser.parse() == 0);
+    CHECK_THAT(request.getHttpVer(), Equals("HTTP/1.1"));
+
+    client.write("Host: localhost\r\n");
+    CHECK(parser.parse() == 0);
+    CHECK_THAT(request.headers.get("Host"), Equals("localhost"));
+
+    client.write("\r\n");
+    CHECK(parser.parse());
+    CHECK(!parser.error());
+}