Move the serialiser to Flipper

Summary:
This change moves the existing serialiser from FlipperWebSocket to FlipperURLSerializer.

The serialiser can be shared with Android as it no longer has any iOS dependencies.

Reviewed By: fabiomassimo

Differential Revision: D31571272

fbshipit-source-id: 0769b384d4143d7404fcfcf993d49dc1b00eeffd

xplat/Flipper/FlipperURLSerializer.cpp

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "FlipperURLSerializer.h"
+#include <iomanip>
+#include <sstream>
+#include "FlipperBase64.h"
+
+namespace facebook {
+namespace flipper {
+
+void URLSerializer::put(std::string key, std::string value) {
+  object_[key] = value;
+}
+void URLSerializer::put(std::string key, int value) {
+  object_[key] = value;
+}
+
+std::string URLSerializer::serialize() {
+  std::string query = "";
+  bool append = false;
+
+  for (auto& pair : object_.items()) {
+    auto key = pair.first.asString();
+    auto value = pair.second.asString();
+    if (append) {
+      query += "&";
+    }
+    query += key;
+    query += "=";
+    if (key == "csr") {
+      query += Base64::encode(value);
+    } else {
+      query += url_encode(value);
+    }
+    append = true;
+  }
+
+  return query;
+}
+
+std::string URLSerializer::url_encode(const std::string& value) {
+  std::ostringstream escaped;
+  escaped.fill('0');
+  escaped << std::hex;
+
+  for (std::string::const_iterator i = value.begin(), n = value.end(); i != n;
+       ++i) {
+    std::string::value_type c = (*i);
+
+    // Keep alphanumeric and other accepted characters intact
+    if (std::isalnum(c) || c == '-' || c == '_' || c == '.' || c == '~') {
+      escaped << c;
+      continue;
+    }
+
+    // Any other characters are percent-encoded
+    escaped << std::uppercase;
+    escaped << '%' << std::setw(2) << int((unsigned char)c);
+    escaped << std::nouppercase;
+  }
+
+  return escaped.str();
+}
+
+} // namespace flipper
+} // namespace facebook

xplat/Flipper/FlipperURLSerializer.h

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <folly/json.h>
+#include <string>
+#include "FlipperTransportTypes.h"
+
+namespace facebook {
+namespace flipper {
+
+class URLSerializer : public FlipperPayloadSerializer {
+ public:
+  void put(std::string key, std::string value) override;
+  void put(std::string key, int value) override;
+
+  std::string serialize() override;
+  ~URLSerializer() {}
+
+ private:
+  std::string url_encode(const std::string& value);
+  folly::dynamic object_ = folly::dynamic::object();
+};
+
+} // namespace flipper
+} // namespace facebook