encapsulate HTTP response creation, add common headers

src/librssguard/network-web/apiserver.cpp

@@ -48,16 +48,11 @@ void ApiServer::answerClient(QTcpSocket* socket, const HttpRequest& request) {
       }
     }
 
-    reply_message = QSL("HTTP/1.0 200 OK \r\n"
+    reply_message = generateHttpAnswer(200,
-                        "Access-Control-Allow-Origin: *\r\n"
+                                       {{QSL("Access-Control-Allow-Origin"), QSL("*")},
-                        "Access-Control-Allow-Headers: *\r\n"
+                                        {QSL("Access-Control-Allow-Headers"), QSL("*")},
-                        "Content-Type: application/json; charset=\"utf-8\"\r\n"
+                                        {QSL("Content-Type"), QSL("application/json; charset=\"utf-8\"")}},
-                        "Content-Length: %1"
+                                       json_data);
-                        "\r\n\r\n")
-                      .arg(QString::number(json_data.size()))
-                      .toLocal8Bit();
-
-    reply_message += json_data;
 
 #if !defined(NDEBUG)
     IOFactory::writeFile("a.out", json_data);
@@ -69,12 +64,10 @@ void ApiServer::answerClient(QTcpSocket* socket, const HttpRequest& request) {
 }
 
 QByteArray ApiServer::processCorsPreflight() const {
-  QString answer = QSL("HTTP/1.0 204 No Content\r\n"
+  return generateHttpAnswer(204,
-                       "Access-Control-Allow-Origin: *\r\n"
+                            {{QSL("Access-Control-Allow-Origin"), QSL("*")},
-                       "Access-Control-Allow-Headers: *\r\n"
+                             {QSL("Access-Control-Allow-Headers"), QSL("*")},
-                       "Access-Control-Allow-Methods: POST, GET, OPTIONS, DELETE\r\n\r\n");
+                             {QSL("Access-Control-Allow-Methods"), QSL("POST, GET, OPTIONS, DELETE")}});
-
-  return answer.toLocal8Bit();
 }
 
 QByteArray ApiServer::processHtmlPage() const {
@@ -88,18 +81,14 @@ QByteArray ApiServer::processHtmlPage() const {
     page = IOFactory::readFile(WEB_UI_FOLDER + QL1C('/') + WEB_UI_FILE);
   }
 
-  QString answer = QSL("HTTP/1.0 200 OK\r\n"
+  QByteArray data = generateHttpAnswer(200,
-                       "Access-Control-Allow-Origin: *\r\n"
+                                       {{QSL("Access-Control-Allow-Origin"), QSL("*")},
-                       "Access-Control-Allow-Headers: *\r\n"
+                                        {QSL("Access-Control-Allow-Headers"), QSL("*")},
-                       "Access-Control-Allow-Methods: POST, GET, OPTIONS, DELETE\r\n"
+                                        {QSL("Access-Control-Allow-Methods"), QSL("POST, GET, OPTIONS, DELETE")},
-                       "Content-Type: text/html; charset=\"utf-8\"\r\n"
+                                        {QSL("Content-Type"), QSL("text/html; charset=\"utf-8\"")}},
-                       "Content-Length: %1\r\n"
+                                       page);
-                       "\r\n")
-                     .arg(QString::number(page.size()));
 
-  QByteArray data = answer.toLocal8Bit();
+  return data;
-
-  return data + page;
 }
 
 ApiResponse ApiServer::processRequest(const ApiRequest& req) const {

src/librssguard/network-web/httpserver.cpp

@@ -4,6 +4,8 @@
 
 #include "definitions/definitions.h"
 
+#include <QDateTime>
+
 HttpServer::HttpServer(QObject* parent) : QObject(parent), m_listenAddress(QHostAddress()), m_listenPort(0) {
   connect(&m_httpServer, &QTcpServer::newConnection, this, &HttpServer::clientConnected);
 
@@ -64,6 +66,35 @@ void HttpServer::setListenAddressPort(const QString& full_uri, bool start_handle
   }
 }
 
+QByteArray HttpServer::generateHttpAnswer(int http_code,
+                                          const QList<HttpHeader>& headers,
+                                          const QByteArray& body) const {
+  QList<HttpHeader> my_headers = headers;
+  QByteArray answer = QSL("HTTP/1.0 %1  \r\n").arg(http_code).toLocal8Bit();
+  int body_length = body.size();
+
+  // Append body length.
+  if (body_length > 0) {
+    my_headers.append({QSL("Content-Length"), QString::number(body_length)});
+  }
+
+  // Append server ID and other common headers.
+  my_headers.append({QSL("Date"), QDateTime::currentDateTimeUtc().toString(Qt::DateFormat::RFC2822Date)});
+  my_headers.append({QSL("Server"), QSL(APP_LONG_NAME)});
+
+  for (const HttpHeader& header : my_headers) {
+    answer.append(QSL("%1: %2\r\n").arg(header.m_name, header.m_value).toLocal8Bit());
+  }
+
+  answer.append(QSL("\r\n").toLocal8Bit());
+
+  if (body_length > 0) {
+    answer.append(body);
+  }
+
+  return answer;
+}
+
 void HttpServer::clientConnected() {
   QTcpSocket* socket = m_httpServer.nextPendingConnection();
 

src/librssguard/network-web/httpserver.h

@@ -35,6 +35,13 @@ class HttpServer : public QObject {
     void setListenAddressPort(const QString& full_uri, bool start_handler);
 
   protected:
+    struct HttpHeader {
+        QString m_name;
+        QString m_value;
+    };
+
+    QByteArray generateHttpAnswer(int http_code, const QList<HttpHeader>& headers, const QByteArray& body = {}) const;
+
     struct HttpRequest {
         bool readMethod(QTcpSocket* socket);
         bool readUrl(QTcpSocket* socket);