feat(http): implement HTTP server with CLI, request, response, and session

handling

src/http/http_cli.cpp

@@ -0,0 +1,34 @@
+#include "http_cli.hpp"
+
+// helper for default values
+constexpr auto withDefault = [](auto value) {
+    using T = decltype(value);
+    return boost::program_options::value<T>()->default_value(value);
+};
+
+HttpCli::HttpCli()
+    : CliBase("HTTP Server Options")
+    , port_(8080)
+    , rootDir_("./www")
+{
+}
+
+void HttpCli::setupOptions()
+{
+    // clang-format off
+    desc_.add_options()
+      ("help,h", "Show help message")
+      ("port,p", withDefault(8080), "Port to listen on")
+      ("root,r", withDefault(std::string("./www")), "Root directory for files");
+    // clang-format on
+}
+
+int HttpCli::getPort() const
+{
+    return vm_["port"].as<int>();
+}
+
+std::string HttpCli::getRootDir() const
+{
+    return vm_["root"].as<std::string>();
+}

src/http/http_cli.hpp

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "cli_base.hpp"
+
+class HttpCli : public CliBase
+{
+  public:
+    HttpCli();
+
+    int getPort() const;
+    std::string getRootDir() const;
+
+  protected:
+    void setupOptions() override;
+
+  private:
+    int port_;
+    std::string rootDir_;
+};

src/http/http_request.cpp

@@ -0,0 +1,70 @@
+#include "http_request.hpp"
+
+#include <stdexcept>
+
+void HttpRequest::setMethod(const std::string_view method)
+{
+    method_ = method;
+}
+
+const std::string HttpRequest::getMethod() const
+{
+    return method_;
+}
+
+void HttpRequest::setPath(const std::string_view path)
+{
+    path_ = path;
+}
+
+const std::string HttpRequest::getPath() const
+{
+    return path_;
+}
+
+void HttpRequest::setVersion(const std::string_view version)
+{
+    version_ = version;
+}
+
+const std::string HttpRequest::getVersion() const
+{
+    return version_;
+}
+
+void HttpRequest::addHeader(
+    const std::string_view key, const std::string_view value
+)
+{
+    headers_[std::string(key)] = std::string(value);
+}
+
+bool HttpRequest::hasHeader(const std::string_view key) const
+{
+    return headers_.find(std::string(key)) != headers_.end();
+}
+
+std::string HttpRequest::getHeader(const std::string_view key) const
+{
+    auto it = headers_.find(std::string(key));
+    if (it == headers_.end()) {
+        throw std::runtime_error("Header not found: " + std::string(key));
+    }
+    return it->second;
+}
+
+const std::unordered_map<std::string, std::string> &
+HttpRequest::getHeaders() const
+{
+    return headers_;
+}
+
+void HttpRequest::setBody(const std::string_view body)
+{
+    body_ = body;
+}
+
+const std::string HttpRequest::getBody() const
+{
+    return body_;
+}

src/http/http_request.hpp

@@ -0,0 +1,34 @@
+#pragma once
+
+#include <string>
+#include <unordered_map>
+
+class HttpRequest
+{
+  public:
+    HttpRequest() = default;
+
+    void setMethod(const std::string_view method);
+    const std::string getMethod() const;
+
+    void setPath(const std::string_view path);
+    const std::string getPath() const;
+
+    void setVersion(const std::string_view version);
+    const std::string getVersion() const;
+
+    void addHeader(const std::string_view key, const std::string_view value);
+    bool hasHeader(const std::string_view key) const;
+    std::string getHeader(const std::string_view key) const;
+    const std::unordered_map<std::string, std::string> &getHeaders() const;
+
+    void setBody(const std::string_view body);
+    const std::string getBody() const;
+
+  private:
+    std::string method_;  // GET, POST
+    std::string path_;    // /index.html
+    std::string version_; // HTTP/1.1
+    std::unordered_map<std::string, std::string> headers_;
+    std::string body_;
+};

src/http/http_request_parser.cpp

@@ -0,0 +1,89 @@
+#include "http_request_parser.hpp"
+
+#include <boost/algorithm/string/trim.hpp>
+#include <sstream>
+#include <stdexcept>
+
+HttpRequest HttpRequestParser::parse(const std::string &raw)
+{
+    std::istringstream stream(raw);
+    HttpRequest request;
+
+    std::string line;
+    if (!std::getline(stream, line)) {
+        throw std::runtime_error("Invalid HTTP request: empty");
+    }
+    if (!line.empty() && line.back() == '\r') {
+        line.pop_back();
+    }
+
+    parseRequestLine(line, request);
+    parseHeaders(stream, request);
+    parseBody(stream, request);
+
+    return request;
+}
+
+// parse "GET /index.html HTTP/1.1"
+void HttpRequestParser::parseRequestLine(
+    const std::string &line, HttpRequest &req
+)
+{
+    std::istringstream requestLine(line);
+    std::string method, path, version;
+    requestLine >> method >> path >> version;
+
+    if (method.empty() || path.empty() || version.empty()) {
+        throw std::runtime_error("Invalid HTTP request line");
+    }
+
+    req.setMethod(method);
+    req.setPath(path);
+    req.setVersion(version);
+}
+
+// parse headers until empty line
+void HttpRequestParser::parseHeaders(
+    std::istringstream &stream, HttpRequest &req
+)
+{
+    std::string line;
+    while (std::getline(stream, line)) {
+        if (!line.empty() && line.back() == '\r') {
+            line.pop_back();
+        }
+        if (line.empty()) {
+            break; // end of headers
+        }
+        parseHeaderLine(line, req);
+    }
+}
+
+// parse single "Key: Value" header
+void HttpRequestParser::parseHeaderLine(
+    const std::string &line, HttpRequest &req
+)
+{
+    auto colon = line.find(':');
+    if (colon == std::string::npos) {
+        return; // skip invalid header
+    }
+
+    std::string key = line.substr(0, colon);
+    std::string value = line.substr(colon + 1);
+
+    boost::algorithm::trim(key);
+    boost::algorithm::trim(value);
+
+    req.addHeader(key, value);
+}
+
+// parse optional body after headers
+void HttpRequestParser::parseBody(std::istringstream &stream, HttpRequest &req)
+{
+    std::string body;
+    std::getline(stream, body, '\0');
+    if (!body.empty()) {
+        req.setBody(body);
+    }
+}

src/http/http_request_parser.hpp

@@ -0,0 +1,16 @@
+#pragma once
+
+#include "http_request.hpp"
+#include <string>
+
+class HttpRequestParser
+{
+  public:
+    static HttpRequest parse(const std::string &raw);
+
+  private:
+    static void parseRequestLine(const std::string &line, HttpRequest &req);
+    static void parseHeaderLine(const std::string &line, HttpRequest &req);
+    static void parseHeaders(std::istringstream &stream, HttpRequest &req);
+    static void parseBody(std::istringstream &stream, HttpRequest &req);
+};

src/http/http_response.cpp

@@ -0,0 +1,95 @@
+#include "http_response.hpp"
+
+#include <sstream>
+#include <stdexcept>
+
+HttpResponse::HttpResponse()
+    : statusCode_(200)
+    , reasonPhrase_("OK")
+    , version_("HTTP/1.1")
+{
+}
+
+void HttpResponse::setStatusCode(int code)
+{
+    statusCode_ = code;
+}
+
+int HttpResponse::getStatusCode() const
+{
+    return statusCode_;
+}
+
+void HttpResponse::setReasonPhrase(const std::string_view phrase)
+{
+    reasonPhrase_ = phrase;
+}
+
+const std::string_view HttpResponse::getReasonPhrase() const
+{
+    return reasonPhrase_;
+}
+
+void HttpResponse::setVersion(const std::string_view version)
+{
+    version_ = version;
+}
+
+const std::string_view HttpResponse::getVersion() const
+{
+    return version_;
+}
+
+void HttpResponse::addHeader(
+    const std::string_view key, const std::string_view value
+)
+{
+    headers_[std::string(key)] = std::string(value);
+}
+
+bool HttpResponse::hasHeader(const std::string_view key) const
+{
+    return headers_.find(std::string(key)) != headers_.end();
+}
+
+std::string HttpResponse::getHeader(const std::string_view key) const
+{
+    auto it = headers_.find(std::string(key));
+    if (it == headers_.end()) {
+        throw std::runtime_error("Header not found: " + std::string(key));
+    }
+    return it->second;
+}
+
+const std::unordered_map<std::string, std::string> &
+HttpResponse::getHeaders() const
+{
+    return headers_;
+}
+
+void HttpResponse::setBody(const std::string_view body)
+{
+    body_ = body;
+}
+
+const std::string_view HttpResponse::getBody() const
+{
+    return body_;
+}
+
+std::string HttpResponse::toString() const
+{
+    std::ostringstream oss;
+
+    oss << version_ << " " << statusCode_ << " " << reasonPhrase_ << "\r\n";
+
+    for (const auto &[key, value] : headers_) {
+        oss << key << ": " << value << "\r\n";
+    }
+
+    oss << "\r\n";
+
+    oss << body_;
+
+    return oss.str();
+}

src/http/http_response.hpp

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <string>
+#include <unordered_map>
+
+class HttpResponse
+{
+  public:
+    HttpResponse();
+
+    void setStatusCode(int code);
+    int getStatusCode() const;
+
+    void setReasonPhrase(const std::string_view phrase);
+    const std::string_view getReasonPhrase() const;
+
+    void setVersion(const std::string_view version);
+    const std::string_view getVersion() const;
+
+    void addHeader(const std::string_view key, const std::string_view value);
+    bool hasHeader(const std::string_view key) const;
+    std::string getHeader(const std::string_view key) const;
+    const std::unordered_map<std::string, std::string> &getHeaders() const;
+
+    void setBody(const std::string_view body);
+    const std::string_view getBody() const;
+
+    std::string toString() const;
+
+  private:
+    int statusCode_;
+    std::string reasonPhrase_;
+    std::string version_;
+    std::unordered_map<std::string, std::string> headers_;
+    std::string body_;
+};

src/http/http_server.cpp

@@ -0,0 +1,15 @@
+#include "http_server.hpp"
+
+#include "http_server.hpp"
+#include "http_session.hpp"
+
+HttpServer::HttpServer(IoContext &io, unsigned short port, std::string rootDir)
+    : TcpServerBase(io, port)
+    , rootDir_(std::move(rootDir))
+{
+}
+
+void HttpServer::createSession(TcpSocket socket)
+{
+    std::make_shared<HttpSession>(std::move(socket), rootDir_)->start();
+}

src/http/http_server.hpp

@@ -0,0 +1,15 @@
+#pragma once
+
+#include "tcp_server_base.hpp"
+
+class HttpServer : public TcpServerBase
+{
+  public:
+    HttpServer(IoContext &io, unsigned short port, std::string rootDir);
+
+  protected:
+    void createSession(TcpSocket socket) override;
+
+  private:
+    std::string rootDir_;
+};

src/http/http_session.cpp

@@ -0,0 +1,61 @@
+#include "http_session.hpp"
+
+#include "session_base.hpp"
+#include "http_request.hpp"
+#include "http_request_parser.hpp"
+#include "http_response.hpp"
+#include "logger.hpp"
+#include <fstream>
+
+HttpSession::HttpSession(TcpSocket socket, std::string rootDir)
+    : SessionBase(std::move(socket))
+    , rootDir_(std::move(rootDir))
+{
+}
+
+void HttpSession::handleRequest(const std::string_view rawRequest)
+{
+    HttpRequest req = HttpRequestParser::parse(std::string(rawRequest));
+
+    HttpResponse res;
+
+    if (req.getPath().rfind("/file/", 0) == 0) {
+        // remove "/file/" prefix
+        std::string filePath = rootDir_ + "/" + req.getPath().substr(6);
+
+        std::ifstream file(filePath, std::ios::binary);
+        if (file) {
+            std::ostringstream ss;
+            ss << file.rdbuf();
+
+            std::string content = ss.str();
+            res.setStatusCode(200);
+            res.setReasonPhrase("OK");
+            res.setBody(content);
+            res.addHeader("Content-Type", "text/plain");
+            res.addHeader("Content-Length", std::to_string(content.size()));
+        } else {
+            res.setStatusCode(404);
+            res.setReasonPhrase("Not Found");
+            res.setBody("File not found");
+            res.addHeader("Content-Type", "text/plain");
+            res.addHeader(
+                "Content-Length", std::to_string(res.getBody().size())
+            );
+        }
+    } else {
+        res.setStatusCode(200);
+        res.setReasonPhrase("OK");
+        res.setBody("Hello, World!");
+        res.addHeader("Content-Type", "text/plain");
+        res.addHeader("Content-Length", std::to_string(res.getBody().size()));
+    }
+
+    std::string responseStr = res.toString();
+    doWrite(responseStr);
+
+    Logger::info(
+        req.getMethod() + " " + req.getPath() + " -> "
+        + std::to_string(res.getStatusCode())
+    );
+}

src/http/http_session.hpp

@@ -0,0 +1,15 @@
+#pragma once
+
+#include "session_base.hpp"
+
+class HttpSession : public SessionBase
+{
+  public:
+    HttpSession(TcpSocket socket, std::string rootDir);
+
+  protected:
+    void handleRequest(const std::string_view rawRequest) override;
+
+  private:
+    std::string rootDir_;
+};

src/main/main_http.cpp

@@ -0,0 +1,29 @@
+#include "http_cli.hpp"
+#include "http_server.hpp"
+#include "logger.hpp"
+
+int main(int argc, char **argv)
+{
+    HttpCli cli;
+    cli.parse(argc, argv);
+
+    if (cli.isHelp()) {
+        cli.printHelp();
+        return 0;
+    }
+
+    Logger::init(true, "http_server.log");
+
+    IoContext io;
+    HttpServer server(io, cli.getPort(), cli.getRootDir());
+
+    Logger::info(
+        "Http server starting on port " + std::to_string(cli.getPort())
+        + ", root dir: " + cli.getRootDir()
+    );
+
+    server.start();
+    io.run();
+
+    return 0;
+}