Merge pull request #1798 from ObiWahn/devel

optional velocypack response

arangod/RestHandler/RestBaseHandler.cpp

@@ -43,16 +43,17 @@ void RestBaseHandler::handleError(Exception const& ex) {
   generateError(GeneralResponse::responseCode(ex.code()), ex.code(), ex.what());
 }
 
+
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief generates a result from VelocyPack
 ////////////////////////////////////////////////////////////////////////////////
 
 void RestBaseHandler::generateResult(GeneralResponse::ResponseCode code,
                                      VPackSlice const& slice) {
-  createResponse(code);
-  _response->setContentType("application/json; charset=utf-8");
 
-  dumpResponse(slice, &VPackOptions::Defaults);
+  createResponse(code);
+  writeResult(slice, VPackOptions::Defaults);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -63,9 +64,7 @@ void RestBaseHandler::generateResult(GeneralResponse::ResponseCode code,
                                      VPackSlice const& slice,
                                      std::shared_ptr<TransactionContext> context) {
   createResponse(code);
-  _response->setContentType("application/json; charset=utf-8");
+  writeResult(slice,*(context->getVPackOptions()));
-  
-  dumpResponse(slice, context->getVPackOptions());
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -90,7 +89,6 @@ void RestBaseHandler::generateError(GeneralResponse::ResponseCode code,
 void RestBaseHandler::generateError(GeneralResponse::ResponseCode code,
                                     int errorCode, std::string const& message) {
   createResponse(code);
-  _response->setContentType("application/json; charset=utf-8");
 
   VPackBuilder builder;
   try {
@@ -106,7 +104,7 @@ void RestBaseHandler::generateError(GeneralResponse::ResponseCode code,
     builder.add("errorNum", VPackValue(errorCode));
     builder.close();
 
-    dumpResponse(builder.slice(), &VPackOptions::Defaults);
+    writeResult(builder.slice(), VPackOptions::Defaults);
   } catch (...) {
     // Building the error response failed
   }
@@ -147,3 +145,28 @@ void RestBaseHandler::dumpResponse(VPackSlice const& slice,
   }
 }
 
+//////////////////////////////////////////////////////////////////////////////
+/// @brief checks if velocypack is expected as answer
+//////////////////////////////////////////////////////////////////////////////
+
+bool RestBaseHandler::returnVelocypack() const {
+  auto accept = std::string(_request->header("accept"));
+  if (std::string::npos == accept.find("application/x-velocypack")) {
+    return false;
+  }
+  return true;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief writes volocypack or json to response
+//////////////////////////////////////////////////////////////////////////////
+
+void RestBaseHandler::writeResult(arangodb::velocypack::Slice const& slice, VPackOptions const& options){
+  if(returnVelocypack()) {
+    _response->setContentType("application/x-velocypack");
+    _response->body().appendText(slice.startAs<const char>(),slice.byteSize());
+  } else {
+    _response->setContentType("application/json; charset=utf-8");
+    dumpResponse(slice, &options);
+  }
+}

arangod/RestHandler/RestBaseHandler.h

@@ -44,11 +44,8 @@ class RestBaseHandler : public rest::HttpHandler {
  public:
   explicit RestBaseHandler(HttpRequest* request);
 
- public:
   void handleError(basics::Exception const&) override;
 
- public:
-
   //////////////////////////////////////////////////////////////////////////////
   /// @brief generates a result from VelocyPack
   //////////////////////////////////////////////////////////////////////////////
@@ -92,6 +89,19 @@ class RestBaseHandler : public rest::HttpHandler {
   /// @brief dumps the response as JSON into the response string buffer
   //////////////////////////////////////////////////////////////////////////////
 
+ protected:
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief checks if velocypack is expected as answer
+  //////////////////////////////////////////////////////////////////////////////
+
+  bool returnVelocypack() const;
+
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief write result back to client
+  //////////////////////////////////////////////////////////////////////////////
+  void writeResult(arangodb::velocypack::Slice const& slice, VPackOptions const& options);
+
+ private:
   void dumpResponse(arangodb::velocypack::Slice const& slice,
                     arangodb::velocypack::Options const* options);
 };

arangod/RestHandler/RestVocbaseBaseHandler.cpp

@@ -236,7 +236,6 @@ void RestVocbaseBaseHandler::generate20x(
 
   VPackSlice slice = result.slice();
   TRI_ASSERT(slice.isObject() || slice.isArray());
-  _response->setContentType("application/json; charset=utf-8");
   if (slice.isObject()) {
     _response->setHeaderNC("etag", "\"" + slice.get(TRI_VOC_ATTRIBUTE_REV).copyString() + "\"");
     // pre 1.4 location headers withdrawn for >= 3.0
@@ -246,14 +245,9 @@ void RestVocbaseBaseHandler::generate20x(
                          std::string("/_db/" + _request->databaseName() +
                                      DOCUMENT_PATH + "/" + escapedHandle));
   }
-  VPackStringBufferAdapter buffer(_response->body().stringBuffer());
+
-  VPackDumper dumper(&buffer, options);
+  writeResult(slice, *options);
-  try {
+
-    dumper.dump(slice);
-  } catch (...) {
-    generateError(GeneralResponse::ResponseCode::SERVER_ERROR, TRI_ERROR_INTERNAL,
-                  "cannot generate output");
-  }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -282,7 +276,6 @@ void RestVocbaseBaseHandler::generatePreconditionFailed(
     VPackSlice const& slice) {
 
   createResponse(GeneralResponse::ResponseCode::PRECONDITION_FAILED);
-  _response->setContentType("application/json; charset=utf-8");
 
   if (slice.isObject()) {  // single document case
     std::string const rev = VelocyPackHelper::getStringValue(slice, TRI_VOC_ATTRIBUTE_REV, "");
@@ -306,16 +299,8 @@ void RestVocbaseBaseHandler::generatePreconditionFailed(
     }
   }
 
-  VPackStringBufferAdapter buffer(_response->body().stringBuffer());
   auto transactionContext(StandaloneTransactionContext::Create(_vocbase));
-  VPackDumper dumper(&buffer, transactionContext->getVPackOptions());
+  writeResult(builder.slice(), *(transactionContext->getVPackOptions()));
-
-  try {
-    dumper.dump(builder.slice());
-  } catch (...) {
-    generateError(GeneralResponse::ResponseCode::SERVER_ERROR, TRI_ERROR_INTERNAL,
-                  "cannot generate output");
-  }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -362,26 +347,27 @@ void RestVocbaseBaseHandler::generateDocument(VPackSlice const& document,
 
   // and generate a response
   createResponse(GeneralResponse::ResponseCode::OK);
-  _response->setContentType("application/json; charset=utf-8");
   if (!rev.empty()) {
     _response->setHeaderNC("etag", "\"" + rev + "\"");
   }
 
   if (generateBody) {
-    VPackStringBufferAdapter buffer(_response->body().stringBuffer());
+    writeResult(document, *options);
-    VPackDumper dumper(&buffer, options);
-    try {
-      dumper.dump(document);
-    } catch (...) {
-      generateError(GeneralResponse::ResponseCode::SERVER_ERROR, TRI_ERROR_INTERNAL,
-                    "cannot generate output");
-    }
   } else {
+    if(returnVelocypack()){
+      //TODO REVIEW
+      _response->setContentType("application/x-velocypack");
+      _response->headResponse(document.byteSize());
+    } else {
+      _response->setContentType("application/json; charset=utf-8");
+
       // TODO can we optimize this?
       // Just dump some where else to find real length
       StringBuffer tmp(TRI_UNKNOWN_MEM_ZONE);
       // convert object to string
       VPackStringBufferAdapter buffer(tmp.stringBuffer());
+
+      //usual dumping -  but not to the response body
       VPackDumper dumper(&buffer, options);
       try {
         dumper.dump(document);
@@ -389,9 +375,11 @@ void RestVocbaseBaseHandler::generateDocument(VPackSlice const& document,
         generateError(GeneralResponse::ResponseCode::SERVER_ERROR, TRI_ERROR_INTERNAL,
                       "cannot generate output");
       }
+      // set the length of what would have been written
       _response->headResponse(tmp.length());
     }
   }
+}
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief generate an error message for a transaction error