Added KIWIX_RESPONSE_DATA to error response

Now the data used to generate an error response can be made to be
embedded in the response as a JS object KIWIX_RESPONSE_DATA.

src/server/response.cpp

@@ -195,6 +195,9 @@ public:
     };
   }
 
+  std::string asJSON() const;
+  void dumpJSON(std::ostream& os) const;
+
 private:
   bool isString() const { return std::holds_alternative<std::string>(data); }
   bool isList()   const { return std::holds_alternative<List>(data); }
@@ -248,15 +251,51 @@ MustacheData ContentResponseBlueprint::Data::toMustache(const std::string& lang)
   }
 }
 
+void ContentResponseBlueprint::Data::dumpJSON(std::ostream& os) const
+{
+  if ( this->isString() ) {
+    os << '"' << escapeForJSON(this->stringValue()) << '"';
+  } else if ( this->isList() ) {
+    const char * sep = " ";
+    os << "[";
+
+    for ( const auto& x :  this->listValue() ) {
+      os << sep;
+      x.dumpJSON(os);
+      sep = ", ";
+    }
+    os << " ]";
+  } else if ( this->isObject() ) {
+    const char * sep = " ";
+    os << "{";
+    for ( const auto& kv : this->objectValue() ) {
+      os << sep << '"' << kv.first << "\" : ";
+      kv.second.dumpJSON(os);
+      sep = ", ";
+    }
+    os << " }";
+  } else {
+    os << (this->boolValue() ? "true" : "false");
+  }
+}
+
+std::string ContentResponseBlueprint::Data::asJSON() const
+{
+  std::ostringstream oss;
+  this->dumpJSON(oss);
+  return oss.str();
+}
 
 ContentResponseBlueprint::ContentResponseBlueprint(const RequestContext* request,
                          int httpStatusCode,
                          const std::string& mimeType,
-                         const std::string& templateStr)
+                         const std::string& templateStr,
+                         bool includeKiwixResponseData)
   : m_request(*request)
   , m_httpStatusCode(httpStatusCode)
   , m_mimeType(mimeType)
   , m_template(templateStr)
+  , m_includeKiwixResponseData(includeKiwixResponseData)
   , m_data(new Data)
 {}
 
@@ -265,6 +304,9 @@ ContentResponseBlueprint::~ContentResponseBlueprint() = default;
 std::unique_ptr<ContentResponse> ContentResponseBlueprint::generateResponseObject() const
 {
   kainjow::mustache::data d = m_data->toMustache(m_request.get_user_language());
+  if ( m_includeKiwixResponseData ) {
+    d.set("KIWIX_RESPONSE_DATA", m_data->asJSON());
+  }
   auto r = ContentResponse::build(m_template, d, m_mimeType);
   r->set_code(m_httpStatusCode);
   return r;
@@ -274,11 +316,13 @@ HTTPErrorResponse::HTTPErrorResponse(const RequestContext& request,
                                      int httpStatusCode,
                                      const std::string& pageTitleMsgId,
                                      const std::string& headingMsgId,
-                                     const std::string& cssUrl)
+                                     const std::string& cssUrl,
+                                     bool includeKiwixResponseData)
   : ContentResponseBlueprint(&request,
                              httpStatusCode,
                              request.get_requested_format() == "html" ? "text/html; charset=utf-8" : "application/xml; charset=utf-8",
-                             request.get_requested_format() == "html" ? RESOURCE::templates::error_html : RESOURCE::templates::error_xml)
+                             request.get_requested_format() == "html" ? RESOURCE::templates::error_html : RESOURCE::templates::error_xml,
+                             includeKiwixResponseData)
 {
   Data::List emptyList;
   *this->m_data = Data(Data::Object{

src/server/response.h

@@ -121,7 +121,8 @@ public: // functions
   ContentResponseBlueprint(const RequestContext* request,
                            int httpStatusCode,
                            const std::string& mimeType,
-                           const std::string& templateStr);
+                           const std::string& templateStr,
+                           bool includeKiwixResponseData = false);
 
   ~ContentResponseBlueprint();
 
@@ -140,6 +141,7 @@ protected: //data
   const int m_httpStatusCode;
   const std::string m_mimeType;
   const std::string m_template;
+  const bool m_includeKiwixResponseData;
   std::unique_ptr<Data> m_data;
 };
 
@@ -149,7 +151,8 @@ struct HTTPErrorResponse : ContentResponseBlueprint
                     int httpStatusCode,
                     const std::string& pageTitleMsgId,
                     const std::string& headingMsgId,
-                    const std::string& cssUrl = "");
+                    const std::string& cssUrl = "",
+                    bool includeKiwixResponseData = false);
 
   HTTPErrorResponse& operator+(const ParameterizedMessage& errorDetails);
   HTTPErrorResponse& operator+=(const ParameterizedMessage& errorDetails);

static/templates/error.html

@@ -5,7 +5,9 @@
     <title>{{PAGE_TITLE}}</title>
 {{#CSS_URL}}
     <link type="text/css" href="{{{CSS_URL}}}" rel="Stylesheet" />
-{{/CSS_URL}}
+{{/CSS_URL}}{{#KIWIX_RESPONSE_DATA}}    <script>
+      const KIWIX_RESPONSE_DATA = {{{KIWIX_RESPONSE_DATA}}};
+    </script>{{/KIWIX_RESPONSE_DATA}}
   </head>
   <body>
     <h1>{{PAGE_HEADING}}</h1>

test/response.cpp

@@ -29,7 +29,8 @@ TEST(HTTPErrorResponse, shouldBeInEnglishByDefault) {
   HTTPErrorResponse errResp(req, MHD_HTTP_NOT_FOUND,
                             "404-page-title",
                             "404-page-heading",
-                            "/css/error.css");
+                            "/css/error.css",
+                            /*includeKiwixResponseData=*/true);
 
   EXPECT_EQ(getResponseContent(errResp),
 R"(<!DOCTYPE html>
@@ -38,6 +39,9 @@ R"(<!DOCTYPE html>
     <meta content="text/html;charset=UTF-8" http-equiv="content-type" />
     <title>Content not found</title>
     <link type="text/css" href="/css/error.css" rel="Stylesheet" />
+    <script>
+      const KIWIX_RESPONSE_DATA = { "CSS_URL" : "/css/error.css", "PAGE_HEADING" : { "msgid" : "404-page-heading", "params" : { } }, "PAGE_TITLE" : { "msgid" : "404-page-title", "params" : { } }, "details" : [ ] };
+    </script>
   </head>
   <body>
     <h1>Not Found</h1>
@@ -56,7 +60,8 @@ TEST(HTTPErrorResponse, shouldBeTranslatable) {
   HTTPErrorResponse errResp(req, MHD_HTTP_NOT_FOUND,
                             "404-page-title",
                             "404-page-heading",
-                            "/css/error.css");
+                            "/css/error.css",
+                            /*includeKiwixResponseData=*/true);
 
   EXPECT_EQ(getResponseContent(errResp),
 R"(<!DOCTYPE html>
@@ -65,6 +70,9 @@ R"(<!DOCTYPE html>
     <meta content="text/html;charset=UTF-8" http-equiv="content-type" />
     <title>[I18N TESTING] Not Found - Try Again</title>
     <link type="text/css" href="/css/error.css" rel="Stylesheet" />
+    <script>
+      const KIWIX_RESPONSE_DATA = { "CSS_URL" : "/css/error.css", "PAGE_HEADING" : { "msgid" : "404-page-heading", "params" : { } }, "PAGE_TITLE" : { "msgid" : "404-page-title", "params" : { } }, "details" : [ ] };
+    </script>
   </head>
   <body>
     <h1>[I18N TESTING] Content not found, but at least the server is alive</h1>