jsonrpc: allow multiple commands in-flight from single JSON connection.

We now keep a list of commands for the jcon instead of a simple
'current' pointer: the assertions become a bit more complex, but
the rest is fairly mechanical.

Fixes: #1007
Reported-by: @ZmnSCPxj
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2018-02-16 13:23:00 +10:30 committed by Christian Decker
parent f7097c76bd
commit 43ec3f0761
3 changed files with 69 additions and 56 deletions

View File

@ -32,10 +32,13 @@ struct json_output {
/* jcon and cmd have separate lifetimes: we detach them on either destruction */
static void destroy_jcon(struct json_connection *jcon)
{
if (jcon->current) {
log_unusual(jcon->log, "Abandoning current command");
jcon->current->jcon = NULL;
struct command *cmd;
list_for_each(&jcon->commands, cmd, list) {
log_unusual(jcon->log, "Abandoning command");
cmd->jcon = NULL;
}
/* Make sure this happens last! */
tal_free(jcon->log);
}
@ -43,7 +46,7 @@ static void destroy_jcon(struct json_connection *jcon)
static void destroy_cmd(struct command *cmd)
{
if (cmd->jcon)
cmd->jcon->current = NULL;
list_del_from(&cmd->jcon->commands, &cmd->list);
}
static void json_help(struct command *cmd,
@ -237,34 +240,35 @@ static const struct json_command *find_cmd(const char *buffer,
return NULL;
}
static void json_done(struct json_connection *jcon, const char *json TAKES)
static void json_done(struct json_connection *jcon,
struct command *cmd,
const char *json TAKES)
{
struct json_output *out = tal(jcon, struct json_output);
out->json = tal_strdup(out, json);
/* Clear existing command (if any: NULL in malformed case) */
jcon->current = tal_free(jcon->current);
tal_free(cmd);
/* Queue for writing. */
/* Queue for writing, and wake writer. */
list_add_tail(&jcon->output, &out->list);
/* Both writer and reader can now continue. */
io_wake(jcon);
}
static void connection_complete_ok(struct json_connection *jcon,
struct command *cmd,
const char *id,
const struct json_result *result)
{
/* This JSON is simple enough that we build manually */
json_done(jcon, take(tal_fmt(jcon,
"{ \"jsonrpc\": \"2.0\", "
"\"result\" : %s,"
" \"id\" : %s }\n",
json_result_string(result), id)));
json_done(jcon, cmd, take(tal_fmt(jcon,
"{ \"jsonrpc\": \"2.0\", "
"\"result\" : %s,"
" \"id\" : %s }\n",
json_result_string(result), id)));
}
static void connection_complete_error(struct json_connection *jcon,
struct command *cmd,
const char *id,
const char *errmsg,
int code,
@ -282,16 +286,16 @@ static void connection_complete_error(struct json_connection *jcon,
else
data_str = "";
json_done(jcon, take(tal_fmt(tmpctx,
"{ \"jsonrpc\": \"2.0\", "
" \"error\" : "
"{ \"code\" : %d,"
" \"message\" : %s%s },"
" \"id\" : %s }\n",
code,
json_result_string(errorres),
data_str,
id)));
json_done(jcon, cmd, take(tal_fmt(tmpctx,
"{ \"jsonrpc\": \"2.0\", "
" \"error\" : "
"{ \"code\" : %d,"
" \"message\" : %s%s },"
" \"id\" : %s }\n",
code,
json_result_string(errorres),
data_str,
id)));
tal_free(tmpctx);
}
@ -370,6 +374,17 @@ void json_add_address(struct json_result *response, const char *fieldname,
json_object_end(response);
}
static bool cmd_in_jcon(const struct json_connection *jcon,
const struct command *cmd)
{
const struct command *i;
list_for_each(&jcon->commands, i, list)
if (i == cmd)
return true;
return false;
}
void command_success(struct command *cmd, struct json_result *result)
{
struct json_connection *jcon = cmd->jcon;
@ -380,8 +395,8 @@ void command_success(struct command *cmd, struct json_result *result)
tal_free(cmd);
return;
}
assert(jcon->current == cmd);
connection_complete_ok(jcon, cmd->id, result);
assert(cmd_in_jcon(jcon, cmd));
connection_complete_ok(jcon, cmd, cmd->id, result);
log_debug(jcon->log, "Success");
}
@ -404,8 +419,8 @@ static void command_fail_v(struct command *cmd,
log_debug(jcon->log, "Failing: %s", error);
assert(jcon->current == cmd);
connection_complete_error(jcon, cmd->id, error, code, data);
assert(cmd_in_jcon(jcon, cmd));
connection_complete_error(jcon, cmd, cmd->id, error, code, data);
}
void command_fail(struct command *cmd, const char *fmt, ...)
{
@ -435,7 +450,7 @@ static void json_command_malformed(struct json_connection *jcon,
const char *id,
const char *error)
{
return connection_complete_error(jcon, id, error,
return connection_complete_error(jcon, NULL, id, error,
JSONRPC2_INVALID_REQUEST, NULL);
}
@ -443,8 +458,8 @@ static void parse_request(struct json_connection *jcon, const jsmntok_t tok[])
{
const jsmntok_t *method, *id, *params;
const struct json_command *cmd;
struct command *c;
assert(!jcon->current);
if (tok[0].type != JSMN_OBJECT) {
json_command_malformed(jcon, "null",
"Expected {} for json command");
@ -467,24 +482,25 @@ static void parse_request(struct json_connection *jcon, const jsmntok_t tok[])
/* This is a convenient tal parent for duration of command
* (which may outlive the conn!). */
jcon->current = tal(jcon->ld, struct command);
jcon->current->jcon = jcon;
jcon->current->ld = jcon->ld;
jcon->current->pending = false;
jcon->current->id = tal_strndup(jcon->current,
json_tok_contents(jcon->buffer, id),
json_tok_len(id));
tal_add_destructor(jcon->current, destroy_cmd);
c = tal(jcon->ld, struct command);
c->jcon = jcon;
c->ld = jcon->ld;
c->pending = false;
c->id = tal_strndup(c,
json_tok_contents(jcon->buffer, id),
json_tok_len(id));
list_add(&jcon->commands, &c->list);
tal_add_destructor(c, destroy_cmd);
if (!method || !params) {
command_fail_detailed(jcon->current,
command_fail_detailed(c,
JSONRPC2_INVALID_REQUEST, NULL,
method ? "No params" : "No method");
return;
}
if (method->type != JSMN_STRING) {
command_fail_detailed(jcon->current,
command_fail_detailed(c,
JSONRPC2_INVALID_REQUEST, NULL,
"Expected string for method");
return;
@ -492,7 +508,7 @@ static void parse_request(struct json_connection *jcon, const jsmntok_t tok[])
cmd = find_cmd(jcon->buffer, method);
if (!cmd) {
command_fail_detailed(jcon->current,
command_fail_detailed(c,
JSONRPC2_METHOD_NOT_FOUND, NULL,
"Unknown command '%.*s'",
(int)(method->end - method->start),
@ -500,7 +516,7 @@ static void parse_request(struct json_connection *jcon, const jsmntok_t tok[])
return;
}
if (cmd->deprecated && !deprecated_apis) {
command_fail_detailed(jcon->current,
command_fail_detailed(c,
JSONRPC2_METHOD_NOT_FOUND, NULL,
"Command '%.*s' is deprecated",
(int)(method->end - method->start),
@ -509,12 +525,12 @@ static void parse_request(struct json_connection *jcon, const jsmntok_t tok[])
}
db_begin_transaction(jcon->ld->wallet->db);
cmd->dispatch(jcon->current, jcon->buffer, params);
cmd->dispatch(c, jcon->buffer, params);
db_commit_transaction(jcon->ld->wallet->db);
/* If they didn't complete it, they must call command_still_pending */
if (jcon->current)
assert(jcon->current->pending);
if (cmd_in_jcon(jcon, c))
assert(c->pending);
}
bool json_get_params(struct command *cmd,
@ -687,12 +703,6 @@ again:
jcon->used -= toks[0].end;
tal_free(toks);
/* Need to wait for command to finish? */
if (jcon->current) {
jcon->len_read = 0;
return io_wait(conn, jcon, read_json, jcon);
}
/* See if we can parse the rest. */
goto again;
@ -713,7 +723,8 @@ static struct io_plan *jcon_connected(struct io_conn *conn,
jcon->used = 0;
jcon->buffer = tal_arr(jcon, char, 64);
jcon->stop = false;
jcon->current = NULL;
list_head_init(&jcon->commands);
/* We want to log on destruction, so we free this in destructor. */
jcon->log = new_log(ld->log_book, ld->log_book, "%sjcon fd %i:",
log_prefix(ld->log), io_conn_fd(conn));

View File

@ -11,6 +11,8 @@ struct wireaddr;
/* Context for a command (from JSON, but might outlive the connection!)
* You can allocate off this for temporary objects. */
struct command {
/* Off jcon->commands */
struct list_node list;
/* The global state */
struct lightningd *ld;
/* The 'id' which we need to include in the response. */
@ -40,8 +42,8 @@ struct json_connection {
/* We've been told to stop. */
bool stop;
/* Current command. */
struct command *current;
/* Current commands. */
struct list_head commands;
struct list_head output;
const char *outbuf;

View File

@ -3434,7 +3434,7 @@ class LightningDTests(BaseLightningDTests):
b'{"id":4,"jsonrpc":"2.0","method":"listpeers","params":[]}',
b'{"id":5,"jsonrpc":"2.0","method":"listpeers","params":[]}',
b'{"id":6,"jsonrpc":"2.0","method":"listpeers","params":[]}',
b'{"method": "invoice", "params": [100, "foo", "foo", 1], "jsonrpc": "2.0", "id": 7 }',
b'{"method": "invoice", "params": [100, "foo", "foo"], "jsonrpc": "2.0", "id": 7 }',
b'{"method": "waitinvoice", "params": ["foo"], "jsonrpc" : "2.0", "id": 8 }',
b'{"method": "delinvoice", "params": ["foo", "unpaid"], "jsonrpc" : "2.0", "id": 9 }',
]