From: Timo Sirainen <tss@iki.fi>
Date: Sun, 10 Mar 2013 18:37:41 +0000 (+0200)
Subject: lib-http: Callback can now request a retry with http_client_request_try_retry()
X-Git-Tag: 2.2.rc3~60
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6c768e0e1ca2da178e79f7435c32ced01f6bcb24;p=thirdparty%2Fdovecot%2Fcore.git

lib-http: Callback can now request a retry with http_client_request_try_retry()
This can be useful for handling "try again" errors from HTTP servers.
---

diff --git a/src/lib-http/http-client-connection.c b/src/lib-http/http-client-connection.c
index 949af799f0..d4bc06590c 100644
--- a/src/lib-http/http-client-connection.c
+++ b/src/lib-http/http-client-connection.c
@@ -392,7 +392,17 @@ http_client_connection_return_response(struct http_client_connection *conn,
 		io_remove(&conn->conn.io);
 	}
 
-	http_client_request_callback(req, response);
+	if (!http_client_request_callback(req, response)) {
+		/* retrying, don't destroy the request */
+		if (response->payload != NULL) {
+			i_stream_unset_destroy_callback(conn->incoming_payload);
+			i_stream_unref(&conn->incoming_payload);
+			conn->conn.io = io_add(conn->conn.fd_in, IO_READ,
+					       http_client_connection_input,
+					       &conn->conn);
+		}
+		return TRUE;
+	}
 
 	// FIXME: conn may be freed at this point..
 
@@ -506,6 +516,7 @@ static void http_client_connection_input(struct connection *_conn)
 		/* remove request from queue */
 		array_delete(&conn->request_wait_list, 0, 1);
 		aborted = (req->state == HTTP_REQUEST_STATE_ABORTED);
+		i_assert(req->refcount > 1 || aborted);
 		http_client_request_unref(&req);
 		
 		conn->close_indicated = response->connection_close;
diff --git a/src/lib-http/http-client-private.h b/src/lib-http/http-client-private.h
index 0dba7ef726..6c2ef75ae6 100644
--- a/src/lib-http/http-client-private.h
+++ b/src/lib-http/http-client-private.h
@@ -191,7 +191,7 @@ int http_client_request_send(struct http_client_request *req,
 			     const char **error_r);
 int http_client_request_send_more(struct http_client_request *req,
 				  const char **error_r);
-void http_client_request_callback(struct http_client_request *req,
+bool http_client_request_callback(struct http_client_request *req,
 	struct http_response *response);
 void http_client_request_resubmit(struct http_client_request *req);
 void http_client_request_retry(struct http_client_request *req,
diff --git a/src/lib-http/http-client-request.c b/src/lib-http/http-client-request.c
index 4525992036..814cba287d 100644
--- a/src/lib-http/http-client-request.c
+++ b/src/lib-http/http-client-request.c
@@ -412,16 +412,25 @@ int http_client_request_send(struct http_client_request *req,
 	return ret;
 }
 
-void http_client_request_callback(struct http_client_request *req,
+bool http_client_request_callback(struct http_client_request *req,
 			     struct http_response *response)
 {
 	http_client_request_callback_t *callback = req->callback;
+	unsigned int orig_attempts = req->attempts;
 
 	req->state = HTTP_REQUEST_STATE_GOT_RESPONSE;
 
 	req->callback = NULL;
-	if (callback != NULL)
+	if (callback != NULL) {
 		callback(response, req->context);
+		if (req->attempts != orig_attempts) {
+			/* retrying */
+			req->callback = callback;
+			http_client_request_resubmit(req);
+			return FALSE;
+		}
+	}
+	return TRUE;
 }
 
 static void
@@ -636,17 +645,21 @@ void http_client_request_resubmit(struct http_client_request *req)
 void http_client_request_retry(struct http_client_request *req,
 	unsigned int status, const char *error)
 {
-	/* limit the number of attempts for each request */
-	if (++req->attempts >= req->client->set.max_attempts) {
-		/* return error */
+	if (!http_client_request_try_retry(req))
 		http_client_request_error(req, status, error);
-		return;
-	}
+}
 
-	http_client_request_debug(req, "Retrying (attempts=%d)", req->attempts);
+bool http_client_request_try_retry(struct http_client_request *req)
+{
+	/* limit the number of attempts for each request */
+	if (req->attempts+1 >= req->client->set.max_attempts)
+		return FALSE;
+	req->attempts++;
 
-	/* resubmit */
-	http_client_request_resubmit(req);
+	http_client_request_debug(req, "Retrying (attempts=%d)", req->attempts);
+	if (req->callback != NULL)
+		http_client_request_resubmit(req);
+	return TRUE;
 }
 
 void http_client_request_set_destroy_callback(struct http_client_request *req,
diff --git a/src/lib-http/http-client.h b/src/lib-http/http-client.h
index a83f47b1a4..0e0423c64a 100644
--- a/src/lib-http/http-client.h
+++ b/src/lib-http/http-client.h
@@ -90,6 +90,7 @@ void http_client_request_set_payload(struct http_client_request *req,
 enum http_request_state
 http_client_request_get_state(struct http_client_request *req);
 void http_client_request_submit(struct http_client_request *req);
+bool http_client_request_try_retry(struct http_client_request *req);
 void http_client_request_abort(struct http_client_request **req);
 
 /* Call the specified callback when HTTP request is destroyed. */