[Lldb-commits] [lldb] [lldb-dap] Refactoring IOStream into Transport handler. (PR #130026)

[Jonas Devlieghere via lldb-commits]

================
@@ -221,52 +222,22 @@ void DAP::StopEventHandlers() {
   }
 }
 
-// Send the JSON in "json_str" to the "out" stream. Correctly send the
-// "Content-Length:" field followed by the length, followed by the raw
-// JSON bytes.
-void DAP::SendJSON(const std::string &json_str) {
-  output.write_full("Content-Length: ");
-  output.write_full(llvm::utostr(json_str.size()));
-  output.write_full("\r\n\r\n");
-  output.write_full(json_str);
-}
-
 // Serialize the JSON value into a string and send the JSON packet to
 // the "out" stream.
 void DAP::SendJSON(const llvm::json::Value &json) {
-  std::string json_str;
-  llvm::raw_string_ostream strm(json_str);
-  strm << json;
-  static std::mutex mutex;
-  std::lock_guard<std::mutex> locker(mutex);
-  SendJSON(json_str);
-
-  DAP_LOG(log, "({0}) <-- {1}", client_name, json_str);
-}
-
-// Read a JSON packet from the "in" stream.
-std::string DAP::ReadJSON() {
-  std::string length_str;
-  std::string json_str;
-  int length;
-
-  if (!input.read_expected(log, "Content-Length: "))
-    return json_str;
-
-  if (!input.read_line(log, length_str))
-    return json_str;
-
-  if (!llvm::to_integer(length_str, length))
-    return json_str;
-
-  if (!input.read_expected(log, "\r\n"))
-    return json_str;
-
-  if (!input.read_full(log, length, json_str))
-    return json_str;
-
-  DAP_LOG(log, "({0}) --> {1}", client_name, json_str);
-  return json_str;
+  // FIXME: Instead of parsing the output message from JSON, pass the `Message`
+  // as parameter to `SendJSON`.
+  protocol::Message message;
+  llvm::json::Path::Root root;
+  if (!fromJSON(json, message, root)) {
+    DAP_LOG_ERROR(log, root.getError(), "({1}) encoding failed: {0}",
+                  client_name);
+    return;
+  }
+  auto err = transport.Write(message);
+  if (err) {
+    DAP_LOG_ERROR(log, std::move(err), "({1}) write failed: {0}", client_name);
+  }
----------------
JDevlieghere wrote:

Nit: the type of `err` is not obvious from the RHS so I don't think `auto` is appropriate. Also no braces for single line `if`s:
```suggestion
  if (llvm::Error err = transport.Write(message)) 
    DAP_LOG_ERROR(log, std::move(err), "({1}) write failed: {0}", client_name);
  ```

https://github.com/llvm/llvm-project/pull/130026