uwsgi/plugins/cache/cache.c

#include <uwsgi.h>

/*

	Plugin for remote access to the uWSGI cache

	For request generating a response containing cache data, we need to make
	a copy to avoid holding the lock too much in case of blocking/slow writes

	uwsgi_cache_safe_get2() will do the job

	the modifier2 is the command to run. Some command is extremely raw, and generally it is mean
	for internal uWSGI usage.

*/

extern struct uwsgi_server uwsgi;

static void cache_command(char *key, uint16_t keylen, char *val, uint16_t vallen, void *data) {

        struct wsgi_request *wsgi_req = (struct wsgi_request *) data;
        uint64_t tmp_vallen = 0;

        if (vallen > 0) {
                if (!uwsgi_strncmp(key, keylen, "key", 3)) {
                        val = uwsgi_cache_get(val, vallen, &tmp_vallen);
                        if (val && tmp_vallen > 0) {
#ifdef UWSGI_DEBUG
				uwsgi_log("cache value size: %llu\n", tmp_vallen);
#endif
				uwsgi_response_write_body_do(wsgi_req, val, tmp_vallen);
                        }

                }
                else if (!uwsgi_strncmp(key, keylen, "get", 3)) {
                        val = uwsgi_cache_get(val, vallen, &tmp_vallen);
                        if (val && vallen > 0) {
				uwsgi_response_write_body_do(wsgi_req, val, tmp_vallen);
                        }
                        else {
				uwsgi_404(wsgi_req);
                        }
                }
        }
}


int uwsgi_cache_request(struct wsgi_request *wsgi_req) {

        uint64_t vallen = 0;
        char *value;
        char *argv[3];
        uint16_t argvs[3];
        uint8_t argc = 0;

        switch(wsgi_req->uh->modifier2) {
                case 0:
                        // get
                        if (wsgi_req->uh->pktsize > 0) {
                                value = uwsgi_cache_get(wsgi_req->buffer, wsgi_req->uh->pktsize, &vallen);
                                if (value && vallen > 0) {
                                        wsgi_req->uh->pktsize = vallen;
					if (uwsgi_response_write_body_do(wsgi_req, (char *)&wsgi_req->uh, 4)) return -1;
					uwsgi_response_write_body_do(wsgi_req, value, vallen);
                                }
                        }
                        break;
                case 1:
                        // set
                        if (wsgi_req->uh->pktsize > 0) {
                                argc = 3;
                                if (!uwsgi_parse_array(wsgi_req->buffer, wsgi_req->uh->pktsize, argv, argvs, &argc)) {
                                        if (argc > 1) {
                                                uwsgi_cache_set(argv[0], argvs[0], argv[1], argvs[1], 0, 0);
                                        }
                                }
                        }
                        break;
                case 2:
                        // del
                        if (wsgi_req->uh->pktsize > 0) {
                                uwsgi_cache_del(wsgi_req->buffer, wsgi_req->uh->pktsize, 0, 0);
                        }
                        break;
                case 3:
                case 4:
                        // dict
                        if (wsgi_req->uh->pktsize > 0) {
                                uwsgi_hooked_parse(wsgi_req->buffer, wsgi_req->uh->pktsize, cache_command, (void *) wsgi_req);
                        }
                        break;
                case 5:
                        // get (uwsgi + stream)
                        if (wsgi_req->uh->pktsize > 0) {
                                value = uwsgi_cache_get(wsgi_req->buffer, wsgi_req->uh->pktsize, &vallen);
                                if (value && vallen > 0) {
                                        wsgi_req->uh->pktsize = 0;
                                        wsgi_req->uh->modifier2 = 1;
					if (uwsgi_response_write_body_do(wsgi_req, (char *)&wsgi_req->uh, 4)) return -1;
					uwsgi_response_write_body_do(wsgi_req, value, vallen);
                                }
                                else {
                                        wsgi_req->uh->pktsize = 0;
                                        wsgi_req->uh->modifier2 = 0;
					if (uwsgi_response_write_body_do(wsgi_req, (char *)&wsgi_req->uh, 4)) return -1;
                                }
                        }
                        break;
		case 6:
			// dump
			wsgi_req->uh->modifier2 = 7;
			struct uwsgi_buffer *cache_dump = uwsgi_buffer_new(4096);
			if (uwsgi_buffer_append_keynum(cache_dump, "items", 5, uwsgi.cache_max_items)) {
				uwsgi_buffer_destroy(cache_dump);
				break;
			}
			if (uwsgi_buffer_append_keynum(cache_dump, "blocksize", 9, uwsgi.cache_blocksize)) {
				uwsgi_buffer_destroy(cache_dump);
				break;
			}

                        wsgi_req->uh->pktsize = cache_dump->pos;
			if (uwsgi_response_write_body_do(wsgi_req, (char *)&wsgi_req->uh, 4)) {
				uwsgi_buffer_destroy(cache_dump);
				return -1;
			}
			uwsgi_response_write_body_do(wsgi_req, cache_dump->buf, cache_dump->pos);
			uwsgi_buffer_destroy(cache_dump);
			uwsgi_wlock(uwsgi.caches->lock);
			int ret = uwsgi_write_nb(wsgi_req->fd, (char *)uwsgi.caches->items, uwsgi.caches->filesize, uwsgi.shared->options[UWSGI_OPTION_SOCKET_TIMEOUT]);
			if (!ret) {
				wsgi_req->response_size += uwsgi.caches->filesize;
			}
			uwsgi_rwunlock(uwsgi.caches->lock);
			break;
        }

        return 0;
}

struct uwsgi_plugin cache_plugin = {

        .name = "cache",
        .modifier1 = 111,
        .request = uwsgi_cache_request,

};