static void
req_forward(struct context *ctx, struct conn *c_conn, struct msg *msg)
{
rstatus_t status;
struct conn *s_conn;
struct server_pool *pool;
uint8_t *key;
uint32_t keylen;
struct keypos *kpos;
ASSERT(c_conn->client && !c_conn->proxy);
/* enqueue message (request) into client outq, if response is expected */
if (!msg->noreply) {
c_conn->enqueue_outq(ctx, c_conn, msg);
}
pool = c_conn->owner;
ASSERT(array_n(msg->keys) > 0);
kpos = array_get(msg->keys, 0);
key = kpos->start;
keylen = (uint32_t)(kpos->end - kpos->start);
s_conn = server_pool_conn(ctx, c_conn->owner, key, keylen);
if (s_conn == NULL) {
req_forward_error(ctx, c_conn, msg);
return;
}
ASSERT(!s_conn->client && !s_conn->proxy);
/* enqueue the message (request) into server inq */
if (TAILQ_EMPTY(&s_conn->imsg_q)) {
status = event_add_out(ctx->evb, s_conn);
if (status != NC_OK) {
req_forward_error(ctx, c_conn, msg);
s_conn->err = errno;
return;
}
}
if (!conn_authenticated(s_conn)) {
status = msg->add_auth(ctx, c_conn, s_conn);
if (status != NC_OK) {
req_forward_error(ctx, c_conn, msg);
s_conn->err = errno;
return;
}
}
s_conn->enqueue_inq(ctx, s_conn, msg);
req_forward_stats(ctx, s_conn->owner, msg);
log_debug(LOG_VERB, "forward from c %d to s %d req %"PRIu64" len %"PRIu32
" type %d with key '%.*s'", c_conn->sd, s_conn->sd, msg->id,
msg->mlen, msg->type, keylen, key);
}
static bool
req_filter(struct context *ctx, struct conn *conn, struct msg *msg)
{
ASSERT(conn->client && !conn->proxy);
if (msg_empty(msg)) {
ASSERT(conn->rmsg == NULL);
log_debug(LOG_VERB, "filter empty req %"PRIu64" from c %d", msg->id,
conn->sd);
req_put(msg);
return true;
}
/*
* Handle "quit\r\n" (memcache) or "*1\r\n$4\r\nquit\r\n" (redis), which
* is the protocol way of doing a passive close. The connection is closed
* as soon as all pending replies have been written to the client.
*/
if (msg->quit) {
log_debug(LOG_INFO, "filter quit req %"PRIu64" from c %d", msg->id,
conn->sd);
if (conn->rmsg != NULL) {
log_debug(LOG_INFO, "discard invalid req %"PRIu64" len %"PRIu32" "
"from c %d sent after quit req", conn->rmsg->id,
conn->rmsg->mlen, conn->sd);
}
conn->eof = 1;
conn->recv_ready = 0;
req_put(msg);
return true;
}
/*
* If this conn is not authenticated, we will mark it as noforward,
* and handle it in the redis_reply handler.
*/
if (!conn_authenticated(conn)) {
msg->noforward = 1;
}
return false;
}
//转发到后端服务器
static void
req_forward(struct context *ctx, struct conn *c_conn, struct msg *msg)
{
rstatus_t status;
struct conn *s_conn;
struct server_pool *pool;
uint8_t *key;
uint32_t keylen;
struct keypos *kpos;
ASSERT(c_conn->client && !c_conn->proxy);
/* enqueue message (request) into client outq, if response is expected */
if (!msg->noreply) {
c_conn->enqueue_outq(ctx, c_conn, msg);
//req_forward把msg入队到客户端连接c_conn->enqueue_outq req_send_done把msg入队到服务端连接s_conn->enqueue_outq
}
pool = c_conn->owner;
ASSERT(array_n(msg->keys) > 0);
kpos = array_get(msg->keys, 0);
key = kpos->start;
keylen = (uint32_t)(kpos->end - kpos->start);
//选举后端服务器并建立连接
s_conn = server_pool_conn(ctx, c_conn->owner, key, keylen);
if (s_conn == NULL) {
req_forward_error(ctx, c_conn, msg);
return;
}
ASSERT(!s_conn->client && !s_conn->proxy);
/* enqueue the message (request) into server inq */
if (TAILQ_EMPTY(&s_conn->imsg_q)) {
//现在队列上面没有msg,但是下面会往该队列加msg,往后端的队列上面有msg,则添加些事件，通过epoll触发发送出去
status = event_add_out(ctx->evb, s_conn); //该写事件触发在core_core中的写事件把imsg_q中的msg发送出去
if (status != NC_OK) {
req_forward_error(ctx, c_conn, msg);
s_conn->err = errno;
return;
}
}
if (!conn_authenticated(s_conn)) { //现在还没有认证成功，则先进行认证
status = msg->add_auth(ctx, c_conn, s_conn);
if (status != NC_OK) {
req_forward_error(ctx, c_conn, msg);
s_conn->err = errno;
return;
}
}
//req_server_enqueue_imsgq
s_conn->enqueue_inq(ctx, s_conn, msg);//在core_core中的写事件把imsg_q中的msg发送出去
req_forward_stats(ctx, s_conn->owner, msg);
log_debug(LOG_VERB, "forward from c %d to s %d req %"PRIu64" len %"PRIu32
" type %d with key '%.*s'", c_conn->sd, s_conn->sd, msg->id,
msg->mlen, msg->type, keylen, key);
}
