static ngx_int_t
ngx_http_push_stream_subscriber_handler(ngx_http_request_t *r)
{
ngx_slab_pool_t *shpool = (ngx_slab_pool_t *)ngx_http_push_stream_shm_zone->shm.addr;
ngx_http_push_stream_loc_conf_t *cf = ngx_http_get_module_loc_conf(r, ngx_http_push_stream_module);
ngx_http_push_stream_subscriber_t *worker_subscriber;
ngx_http_push_stream_requested_channel_t *channels_ids, *cur;
ngx_http_push_stream_subscriber_ctx_t *ctx;
time_t if_modified_since;
ngx_str_t *last_event_id, vv_time = ngx_null_string;
ngx_str_t *push_mode;
ngx_flag_t polling, longpolling;
ngx_int_t rc;
ngx_int_t status_code;
ngx_str_t *explain_error_message;
// add headers to support cross domain requests
if (cf->allowed_origins.len > 0) {
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ACCESS_CONTROL_ALLOW_ORIGIN, &cf->allowed_origins);
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ACCESS_CONTROL_ALLOW_METHODS, &NGX_HTTP_PUSH_STREAM_ALLOW_GET);
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ACCESS_CONTROL_ALLOW_HEADERS, &NGX_HTTP_PUSH_STREAM_ALLOWED_HEADERS);
}
if (r->method & NGX_HTTP_OPTIONS) {
return ngx_http_push_stream_send_only_header_response(r, NGX_HTTP_OK, NULL);
}
// only accept GET method
if (!(r->method & NGX_HTTP_GET)) {
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ALLOW, &NGX_HTTP_PUSH_STREAM_ALLOW_GET);
return ngx_http_push_stream_send_only_header_response(r, NGX_HTTP_NOT_ALLOWED, NULL);
}
if ((ctx = ngx_http_push_stream_add_request_context(r)) == NULL) {
ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to create request context");
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
//get channels ids and backtracks from path
channels_ids = ngx_http_push_stream_parse_channels_ids_from_path(r, ctx->temp_pool);
if ((channels_ids == NULL) || ngx_queue_empty(&channels_ids->queue)) {
ngx_log_error(NGX_LOG_WARN, r->connection->log, 0, "push stream module: the $push_stream_channels_path variable is required but is not set");
return ngx_http_push_stream_send_only_header_response(r, NGX_HTTP_BAD_REQUEST, &NGX_HTTP_PUSH_STREAM_NO_CHANNEL_ID_MESSAGE);
}
//validate channels: name, length and quantity. check if channel exists when authorized_channels_only is on. check if channel is full of subscribers
if (ngx_http_push_stream_validate_channels(r, channels_ids, &status_code, &explain_error_message) == NGX_ERROR) {
return ngx_http_push_stream_send_only_header_response(r, status_code, explain_error_message);
}
if (cf->last_received_message_time != NULL) {
ngx_http_push_stream_complex_value(r, cf->last_received_message_time, &vv_time);
} else if (r->headers_in.if_modified_since != NULL) {
vv_time = r->headers_in.if_modified_since->value;
}
// get control headers
if_modified_since = vv_time.len ? ngx_http_parse_time(vv_time.data, vv_time.len) : -1;
last_event_id = ngx_http_push_stream_get_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_LAST_EVENT_ID);
push_mode = ngx_http_push_stream_get_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_MODE);
polling = ((cf->location_type == NGX_HTTP_PUSH_STREAM_SUBSCRIBER_MODE_POLLING) || ((push_mode != NULL) && (push_mode->len == NGX_HTTP_PUSH_STREAM_MODE_POLLING.len) && (ngx_strncasecmp(push_mode->data, NGX_HTTP_PUSH_STREAM_MODE_POLLING.data, NGX_HTTP_PUSH_STREAM_MODE_POLLING.len) == 0)));
longpolling = ((cf->location_type == NGX_HTTP_PUSH_STREAM_SUBSCRIBER_MODE_LONGPOLLING) || ((push_mode != NULL) && (push_mode->len == NGX_HTTP_PUSH_STREAM_MODE_LONGPOLLING.len) && (ngx_strncasecmp(push_mode->data, NGX_HTTP_PUSH_STREAM_MODE_LONGPOLLING.data, NGX_HTTP_PUSH_STREAM_MODE_LONGPOLLING.len) == 0)));
if (polling || longpolling) {
ngx_int_t result = ngx_http_push_stream_subscriber_polling_handler(r, channels_ids, if_modified_since, last_event_id, longpolling, ctx->temp_pool);
if (ctx->temp_pool != NULL) {
ngx_destroy_pool(ctx->temp_pool);
ctx->temp_pool = NULL;
}
return result;
}
ctx->padding = ngx_http_push_stream_get_padding_by_user_agent(r);
// stream access
if ((worker_subscriber = ngx_http_push_stream_subscriber_prepare_request_to_keep_connected(r)) == NULL) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_TRANSFER_ENCODING, &NGX_HTTP_PUSH_STREAM_HEADER_CHUNCKED);
ngx_http_send_header(r);
// sending response content header
if (ngx_http_push_stream_send_response_content_header(r, cf) == NGX_ERROR) {
ngx_log_error(NGX_LOG_ERR, (r)->connection->log, 0, "push stream module: could not send content header to subscriber");
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
ngx_shmtx_lock(&shpool->mutex);
rc = ngx_http_push_stream_registry_subscriber_locked(r, worker_subscriber);
ngx_shmtx_unlock(&shpool->mutex);
if (rc == NGX_ERROR) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
// adding subscriber to channel(s) and send backtrack messages
cur = channels_ids;
while ((cur = (ngx_http_push_stream_requested_channel_t *) ngx_queue_next(&cur->queue)) != channels_ids) {
if (ngx_http_push_stream_subscriber_assign_channel(shpool, cf, r, cur, if_modified_since, last_event_id, worker_subscriber, ctx->temp_pool) != NGX_OK) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
}
if (ctx->temp_pool != NULL) {
ngx_destroy_pool(ctx->temp_pool);
ctx->temp_pool = NULL;
}
return NGX_DONE;
}
static ngx_int_t
ngx_http_push_stream_subscriber_handler(ngx_http_request_t *r)
{
ngx_http_push_stream_main_conf_t *mcf = ngx_http_get_module_main_conf(r, ngx_http_push_stream_module);
ngx_http_push_stream_loc_conf_t *cf = ngx_http_get_module_loc_conf(r, ngx_http_push_stream_module);
ngx_http_push_stream_subscriber_t *worker_subscriber;
ngx_http_push_stream_requested_channel_t *requested_channels, *requested_channel;
ngx_queue_t *q;
ngx_http_push_stream_module_ctx_t *ctx;
ngx_int_t tag;
time_t if_modified_since;
ngx_str_t *last_event_id = NULL;
ngx_str_t *push_mode;
ngx_flag_t polling, longpolling;
ngx_int_t status_code;
ngx_str_t *explain_error_message;
ngx_str_t vv_allowed_origins = ngx_null_string;
// add headers to support cross domain requests
if (cf->allowed_origins != NULL) {
ngx_http_push_stream_complex_value(r, cf->allowed_origins, &vv_allowed_origins);
}
if (vv_allowed_origins.len > 0) {
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ACCESS_CONTROL_ALLOW_ORIGIN, &vv_allowed_origins);
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ACCESS_CONTROL_ALLOW_METHODS, &NGX_HTTP_PUSH_STREAM_ALLOW_GET);
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ACCESS_CONTROL_ALLOW_HEADERS, &NGX_HTTP_PUSH_STREAM_ALLOWED_HEADERS);
}
if (r->method & NGX_HTTP_OPTIONS) {
return ngx_http_push_stream_send_only_header_response(r, NGX_HTTP_OK, NULL);
}
ngx_http_push_stream_set_expires(r, NGX_HTTP_PUSH_STREAM_EXPIRES_EPOCH, 0);
// only accept GET method
if (!(r->method & NGX_HTTP_GET)) {
ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_ALLOW, &NGX_HTTP_PUSH_STREAM_ALLOW_GET);
return ngx_http_push_stream_send_only_header_response(r, NGX_HTTP_NOT_ALLOWED, NULL);
}
if ((ctx = ngx_http_push_stream_add_request_context(r)) == NULL) {
ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: unable to create request context");
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
//get channels ids and backtracks from path
requested_channels = ngx_http_push_stream_parse_channels_ids_from_path(r, r->pool);
if ((requested_channels == NULL) || ngx_queue_empty(&requested_channels->queue)) {
ngx_log_error(NGX_LOG_WARN, r->connection->log, 0, "push stream module: the push_stream_channels_path is required but is not set");
return ngx_http_push_stream_send_only_header_response(r, NGX_HTTP_BAD_REQUEST, &NGX_HTTP_PUSH_STREAM_NO_CHANNEL_ID_MESSAGE);
}
//validate channels: name, length and quantity. check if channel exists when authorized_channels_only is on. check if channel is full of subscribers
if (ngx_http_push_stream_validate_channels(r, requested_channels, &status_code, &explain_error_message) == NGX_ERROR) {
return ngx_http_push_stream_send_only_header_response(r, status_code, explain_error_message);
}
// get control values
ngx_http_push_stream_get_last_received_message_values(r, &if_modified_since, &tag, &last_event_id);
push_mode = ngx_http_push_stream_get_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_MODE);
polling = ((cf->location_type == NGX_HTTP_PUSH_STREAM_SUBSCRIBER_MODE_POLLING) || ((push_mode != NULL) && (push_mode->len == NGX_HTTP_PUSH_STREAM_MODE_POLLING.len) && (ngx_strncasecmp(push_mode->data, NGX_HTTP_PUSH_STREAM_MODE_POLLING.data, NGX_HTTP_PUSH_STREAM_MODE_POLLING.len) == 0)));
longpolling = ((cf->location_type == NGX_HTTP_PUSH_STREAM_SUBSCRIBER_MODE_LONGPOLLING) || ((push_mode != NULL) && (push_mode->len == NGX_HTTP_PUSH_STREAM_MODE_LONGPOLLING.len) && (ngx_strncasecmp(push_mode->data, NGX_HTTP_PUSH_STREAM_MODE_LONGPOLLING.data, NGX_HTTP_PUSH_STREAM_MODE_LONGPOLLING.len) == 0)));
if (polling || longpolling) {
ngx_int_t result = ngx_http_push_stream_subscriber_polling_handler(r, requested_channels, if_modified_since, tag, last_event_id, longpolling, ctx->temp_pool);
if (ctx->temp_pool != NULL) {
ngx_destroy_pool(ctx->temp_pool);
ctx->temp_pool = NULL;
}
return result;
}
ctx->padding = ngx_http_push_stream_get_padding_by_user_agent(r);
// stream access
if ((worker_subscriber = ngx_http_push_stream_subscriber_prepare_request_to_keep_connected(r)) == NULL) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
ngx_http_send_header(r);
// sending response content header
if (ngx_http_push_stream_send_response_content_header(r, cf) == NGX_ERROR) {
ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "push stream module: could not send content header to subscriber");
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
if (ngx_http_push_stream_registry_subscriber(r, worker_subscriber) == NGX_ERROR) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
// adding subscriber to channel(s) and send old messages
for (q = ngx_queue_head(&requested_channels->queue); q != ngx_queue_sentinel(&requested_channels->queue); q = ngx_queue_next(q)) {
requested_channel = ngx_queue_data(q, ngx_http_push_stream_requested_channel_t, queue);
if (ngx_http_push_stream_subscriber_assign_channel(mcf, cf, r, requested_channel, if_modified_since, tag, last_event_id, worker_subscriber, ctx->temp_pool) != NGX_OK) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
}
if (ctx->temp_pool != NULL) {
ngx_destroy_pool(ctx->temp_pool);
ctx->temp_pool = NULL;
}
return NGX_DONE;
}
