JSON: don't return a raw result string for "stop" and "recover".

In general, results should always be an object, so we can add new fields
later (e.g. warnings!).  But we violated this for "stop", and when "recover"
used the same infrastructure, it started doing the same thing.

I'm assuming nobody cares, so we don't need to do a deprecation cycle.

Changelog-Changed: JSON-RPC: `stop` and `recover` now return a JSON object (not a raw string!) like every other command does.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

.msggen.json

@@ -334,6 +334,9 @@
             "complete": 1,
             "pending": 0
         },
+        "StopResult": {
+            "Shutdown complete": 0
+        },
         "WaitIndexname": {
             "created": 0,
             "deleted": 2,
@@ -1687,6 +1690,9 @@
         "StaticbackupResponse": {
             "StaticBackup.scb[]": 1
         },
+        "StopResponse": {
+            "Stop.result": 1
+        },
         "TxdiscardRequest": {
             "TxDiscard.txid": 1
         },
@@ -5982,6 +5988,10 @@
             "added": "pre-v0.10.1",
             "deprecated": null
         },
+        "Stop.result": {
+            "added": "v24.05",
+            "deprecated": false
+        },
         "TxDiscard": {
             "added": "pre-v0.10.1",
             "deprecated": null

cln-grpc/proto/node.proto

@@ -1951,6 +1951,11 @@ message StopRequest {
 }
 
 message StopResponse {
+	// Stop.result
+	enum StopResult {
+		SHUTDOWN_COMPLETE = 0;
+	}
+	optional StopResult result = 1;
 }
 
 message PreapprovekeysendRequest {

cln-grpc/src/convert.rs

@@ -1825,6 +1825,7 @@ impl From<responses::WaitResponse> for pb::WaitResponse {
 impl From<responses::StopResponse> for pb::StopResponse {
     fn from(c: responses::StopResponse) -> Self {
         Self {
+            result: c.result.map(|v| v as i32),
         }
     }
 }

cln-rpc/src/model.rs

@@ -5951,8 +5951,34 @@ pub mod responses {
 	    }
 	}
 
+	#[derive(Copy, Clone, Debug, Deserialize, Serialize, PartialEq, Eq)]
+	pub enum StopResult {
+	    #[serde(rename = "Shutdown complete")]
+	    SHUTDOWN_COMPLETE,
+	}
+
+	impl TryFrom<i32> for StopResult {
+	    type Error = anyhow::Error;
+	    fn try_from(c: i32) -> Result<StopResult, anyhow::Error> {
+	        match c {
+	    0 => Ok(StopResult::SHUTDOWN_COMPLETE),
+	            o => Err(anyhow::anyhow!("Unknown variant {} for enum StopResult", o)),
+	        }
+	    }
+	}
+
+	impl ToString for StopResult {
+	    fn to_string(&self) -> String {
+	        match self {
+	            StopResult::SHUTDOWN_COMPLETE => "SHUTDOWN_COMPLETE",
+	        }.to_string()
+	    }
+	}
+
 	#[derive(Clone, Debug, Deserialize, Serialize)]
 	pub struct StopResponse {
+	    #[serde(skip_serializing_if = "Option::is_none")]
+	    pub result: Option<StopResult>,
 	}
 
 	impl TryFrom<Response> for StopResponse {

contrib/pyln-grpc-proto/pyln/grpc/node_pb2.py

@@ -20,6 +20,7 @@ _globals = globals()
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
 _builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'node_pb2', _globals)
 if _descriptor._USE_C_DESCRIPTORS == False:
+
   DESCRIPTOR._options = None
   _globals['_GETINFOREQUEST']._serialized_start=37
   _globals['_GETINFOREQUEST']._serialized_end=53

contrib/pyln-grpc-proto/pyln/grpc/primitives_pb2.py

@@ -19,6 +19,7 @@ _globals = globals()
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
 _builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'primitives_pb2', _globals)
 if _descriptor._USE_C_DESCRIPTORS == False:
+
   DESCRIPTOR._options = None
   _globals['_CHANNELSIDE']._serialized_start=718
   _globals['_CHANNELSIDE']._serialized_end=754

contrib/pyln-testing/pyln/testing/grpc2py.py

@@ -1515,6 +1515,7 @@ def wait2py(m):
 
 def stop2py(m):
     return remove_default({
+        "result": str(m.result),  # EnumField in generate_composite
     })
 
 

doc/lightning-stop.7.md

@@ -25,7 +25,10 @@ RETURN VALUE
 ------------
 
 [comment]: # (GENERATE-FROM-SCHEMA-START)
-On success, returns a single element (string) (always "Shutdown complete")
+On success, an object is returned, containing:
+
+- **result** (string) (always "Shutdown complete") *(added v24.05)*
+
 [comment]: # (GENERATE-FROM-SCHEMA-END)
 
 Once it has returned, the daemon has cleaned up completely, and if
@@ -43,4 +46,4 @@ RESOURCES
 
 Main web site: <https://github.com/ElementsProject/lightning>
 
-[comment]: # ( SHA256STAMP:d070207640745cfc9b9ba26e5d023e96a3befcdde9a2c9b17d48d46dafb460f9)
+[comment]: # ( SHA256STAMP:879e99c76bb615e2c7f7356ff24b748ef42ff11cf692d1f199c60aacf9c09e0b)

doc/schemas/stop.schema.json

@@ -1,7 +1,17 @@
 {
   "$schema": "http://json-schema.org/draft-07/schema#",
-  "type": "string",
-  "enum": [
-    "Shutdown complete"
-  ]
+  "type": "object",
+  "additionalProperties": false,
+  "required": [
+    "result"
+  ],
+  "properties": {
+    "result": {
+	"type": "string",
+	"added": "v24.05",
+	"enum": [
+	    "Shutdown complete"
+	]
+    }
+  }
 }

lightningd/jsonrpc.c

@@ -213,16 +213,17 @@ static struct command_result *prepare_stop_conn(struct command *cmd,
 
 	cmd->ld->stop_conn = cmd->jcon->conn;
 
-	/* This is the one place where result is a literal string. */
 	jout = json_out_new(tmpctx);
 	json_out_start(jout, NULL, '{');
 	json_out_addstr(jout, "jsonrpc", "2.0");
 	/* Copy input id token exactly */
 	memcpy(json_out_member_direct(jout, "id", strlen(cmd->id)),
 	       cmd->id, strlen(cmd->id));
+	json_out_start(jout, "result", '{');
 	json_out_addstr(jout, "result", why);
 	json_out_end(jout, '}');
-	json_out_finished(jout);
+	json_out_end(jout, '}');
+ 	json_out_finished(jout);
 
 	/* Add two \n */
 	memcpy(json_out_direct(jout, 2), "\n\n", strlen("\n\n"));