[Lldb-commits] [lldb] 165f45a - [lldb][lldb-vscode] Pretty print JSON to log files

[David Spickett via lldb-commits]

Author: David Spickett
Date: 2023-08-03T15:09:12Z
New Revision: 165f45a877742a74988d63f36aee635c8e0a47da

URL: https://github.com/llvm/llvm-project/commit/165f45a877742a74988d63f36aee635c8e0a47da
DIFF: https://github.com/llvm/llvm-project/commit/165f45a877742a74988d63f36aee635c8e0a47da.diff

LOG: [lldb][lldb-vscode] Pretty print JSON to log files

This makes anlysing test failures much more easy.

For SendJSON this is simple, just use llvm::format instead.

For GetNextObject/ReadJSON it's a bit more tricky.
* Print the "Content-Length:" line in ReadJSON, but not the json.
* Back in GetNextObject, if the JSON doesn't parse, it'll be
  printed as a normal string along with an error message.
* If we didn't error before, we have a JSON value so we pretty print it.
* Finally, if it isn't an object we'll log an error for that,
  not including the JSON.

Before:
```
<--
Content-Length: 81

{"command":"disconnect","request_seq":5,"seq":0,"success":true,"type":"response"}
```

After:
```
<--
Content-Length: 81

{
  "command": "disconnect",
  "request_seq": 5,
  "seq": 0,
  "success": true,
  "type": "response"
}
```

There appear to be some responses that include strings that are themselves JSON,
and this won't pretty print those but I think it's still worth doing.

Reviewed By: wallace

Differential Revision: https://reviews.llvm.org/D156979

Added: 
    

Modified: 
    lldb/tools/lldb-vscode/VSCode.cpp

Removed: 
    


################################################################################
diff  --git a/lldb/tools/lldb-vscode/VSCode.cpp b/lldb/tools/lldb-vscode/VSCode.cpp
index cad67c4273dd53..85e1f4b4ac06e4 100644
--- a/lldb/tools/lldb-vscode/VSCode.cpp
+++ b/lldb/tools/lldb-vscode/VSCode.cpp
@@ -89,12 +89,6 @@ void VSCode::SendJSON(const std::string &json_str) {
   output.write_full(llvm::utostr(json_str.size()));
   output.write_full("\r\n\r\n");
   output.write_full(json_str);
-
-  if (log) {
-    *log << "<-- " << std::endl
-         << "Content-Length: " << json_str.size() << "\r\n\r\n"
-         << json_str << std::endl;
-  }
 }
 
 // Serialize the JSON value into a string and send the JSON packet to
@@ -105,7 +99,14 @@ void VSCode::SendJSON(const llvm::json::Value &json) {
   strm << json;
   static std::mutex mutex;
   std::lock_guard<std::mutex> locker(mutex);
-  SendJSON(strm.str());
+  std::string json_str = strm.str();
+  SendJSON(json_str);
+
+  if (log) {
+    *log << "<-- " << std::endl
+         << "Content-Length: " << json_str.size() << "\r\n\r\n"
+         << llvm::formatv("{0:2}", json).str() << std::endl;
+  }
 }
 
 // Read a JSON packet from the "in" stream.
@@ -129,11 +130,8 @@ std::string VSCode::ReadJSON() {
   if (!input.read_full(log.get(), length, json_str))
     return json_str;
 
-  if (log) {
-    *log << "--> " << std::endl
-         << "Content-Length: " << length << "\r\n\r\n"
-         << json_str << std::endl;
-  }
+  if (log)
+    *log << "--> " << std::endl << "Content-Length: " << length << "\r\n\r\n";
 
   return json_str;
 }
@@ -523,6 +521,11 @@ PacketStatus VSCode::GetNextObject(llvm::json::Object &object) {
     }
     return PacketStatus::JSONMalformed;
   }
+
+  if (log) {
+    *log << llvm::formatv("{0:2}", *json_value).str() << std::endl;
+  }
+
   llvm::json::Object *object_ptr = json_value->getAsObject();
   if (!object_ptr) {
     if (log)