libplugin: don't turn non-string JSON ids into strings.

When called with `"id": 1` we replied with `"id": "1"`.  lightningd doesn't
actually care, but it's weird.

Copy the entire token: this way we don't have to special case anything.

Also, remove the doubled test in json_add_jsonstr.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

common/json_parse_simple.c

@@ -206,7 +206,9 @@ const char *json_get_id(const tal_t *ctx,
 	const jsmntok_t *idtok = json_get_member(buffer, obj, "id");
 	if (!idtok)
 		return NULL;
-	return json_strdup(ctx, buffer, idtok);
+	return tal_strndup(ctx,
+			   json_tok_full(buffer, idtok),
+			   json_tok_full_len(idtok));
 }
 
 /*-----------------------------------------------------------------------------

common/json_parse_simple.h

@@ -66,7 +66,7 @@ const jsmntok_t *json_get_member(const char *buffer, const jsmntok_t tok[],
 /* Get index'th array member. */
 const jsmntok_t *json_get_arr(const jsmntok_t tok[], size_t index);
 
-/* Helper to get "id" field from object. */
+/* Helper to get "id" field from object (including any quotes!). */
 const char *json_get_id(const tal_t *ctx,
 			const char *buffer, const jsmntok_t *obj);
 

common/json_stream.c

@@ -239,9 +239,6 @@ void json_add_jsonstr(struct json_stream *js,
 {
 	char *p;
 
-	if (!json_filter_ok(js->filter, fieldname))
-		return;
-
 	/* NOTE: Filtering doesn't really work here! */
 	if (!json_filter_ok(js->filter, fieldname))
 		return;
@@ -690,3 +687,11 @@ void json_add_lease_rates(struct json_stream *result,
 		     rates->channel_fee_max_proportional_thousandths);
 }
 
+void json_add_id(struct json_stream *result, const char *id)
+{
+	char *p;
+
+	/* Bypass escape-required assertion in json_out_add */
+	p = json_member_direct(result, "id", strlen(id));
+	memcpy(p, id, strlen(id));
+}

common/json_stream.h

@@ -390,4 +390,7 @@ void json_add_psbt(struct json_stream *stream,
  * Note that field names are set */
 void json_add_lease_rates(struct json_stream *result,
 			  const struct lease_rates *rates);
+
+/* Add an id field literally (i.e. it's already a JSON primitive or string!) */
+void json_add_id(struct json_stream *result, const char *id);
 #endif /* LIGHTNING_COMMON_JSON_STREAM_H */

plugins/libplugin.c

@@ -177,14 +177,22 @@ static const char *get_json_id(const tal_t *ctx,
 			       const char *cmd_id,
 			       const char *method)
 {
-	if (cmd_id)
+	const char *prefix;
-		return tal_fmt(ctx, "%s/%s:%s#%"PRIu64,
+
-			       cmd_id,
+	if (cmd_id) {
-			       plugin->id, method,
+		/* Strip quotes! */
-			       plugin->next_outreq_id++);
+		if (strstarts(cmd_id, "\"")) {
-	return tal_fmt(ctx, "%s:%s#%"PRIu64,
+			assert(strlen(cmd_id) >= 2);
-		       plugin->id, method,
+			assert(strends(cmd_id, "\""));
-		       plugin->next_outreq_id++);
+			prefix = tal_fmt(tmpctx, "%.*s/",
+					 (int)strlen(cmd_id) - 2, cmd_id + 1);
+		} else
+			prefix = tal_fmt(tmpctx, "%s/", cmd_id);
+	} else
+		prefix = "";
+
+	return tal_fmt(ctx, "\"%s%s:%s#%"PRIu64"\"",
+		       prefix, plugin->id, method, plugin->next_outreq_id++);
 }
 
 static void destroy_out_req(struct out_req *out_req, struct plugin *plugin)
@@ -225,7 +233,7 @@ jsonrpc_request_start_(struct plugin *plugin, struct command *cmd,
 	out->js = new_json_stream(NULL, cmd, NULL);
 	json_object_start(out->js, NULL);
 	json_add_string(out->js, "jsonrpc", "2.0");
-	json_add_string(out->js, "id", out->id);
+	json_add_id(out->js, out->id);
 	json_add_string(out->js, "method", method);
 	if (out->errcb)
 		json_object_start(out->js, "params");
@@ -251,7 +259,7 @@ static struct json_stream *jsonrpc_stream_start(struct command *cmd)
 
 	json_object_start(js, NULL);
 	json_add_string(js, "jsonrpc", "2.0");
-	json_add_string(js, "id", cmd->id);
+	json_add_id(js, cmd->id);
 
 	return js;
 }
@@ -548,10 +556,12 @@ static const jsmntok_t *sync_req(const tal_t *ctx,
 	const jsmntok_t *contents;
 	int reqlen;
 	struct json_out *jout = json_out_new(tmpctx);
+	const char *id = get_json_id(tmpctx, plugin, "init", method);
 
 	json_out_start(jout, NULL, '{');
 	json_out_addstr(jout, "jsonrpc", "2.0");
-	json_out_addstr(jout, "id", get_json_id(tmpctx, plugin, "init", method));
+	/* Copy in id *literally* */
+	memcpy(json_out_member_direct(jout, "id", strlen(id)), id, strlen(id));
 	json_out_addstr(jout, "method", method);
 	json_out_add_splice(jout, "params", params);
 	if (taken(params))
@@ -810,8 +820,8 @@ static void handle_rpc_reply(struct plugin *plugin, const jsmntok_t *toks)
 		return;
 
 	out = strmap_getn(&plugin->out_reqs,
-			  buf + idtok->start,
+			  json_tok_full(buf, idtok),
-			  idtok->end - idtok->start);
+			  json_tok_full_len(idtok));
 	if (!out) {
 		/* This can actually happen, if they free req! */
 		plugin_log(plugin, LOG_DBG, "JSON reply with unknown id '%.*s'",
@@ -1376,7 +1386,7 @@ struct json_stream *plugin_notify_start(struct command *cmd, const char *method)
 	json_add_string(js, "method", method);
 
 	json_object_start(js, "params");
-	json_add_string(js, "id", cmd->id);
+	json_add_id(js, cmd->id);
 
 	return js;
 }