Apache扩展对于webservice指定机器请求

Mod_jk是apache module模块中鼎鼎大名的

static int jk_handler(request_rec * r)
{
    const char *worker_name;
    jk_server_conf_t *xconf;
    jk_request_conf_t *rconf;
    int rc, dmt = 1;
    int worker_name_extension = JK_FALSE;

    /* We do DIR_MAGIC_TYPE here to make sure TC gets all requests, even
     * if they are directory requests, in case there are no static files
     * visible to Apache and/or DirectoryIndex was not used. This is only
     * used when JkOptions has ForwardDirectories set. */
    /* Not for me, try next handler */
    if (strcmp(r->handler, JK_HANDLER)
        && (dmt = strcmp(r->handler, DIR_MAGIC_TYPE)))
        return DECLINED;

    xconf = (jk_server_conf_t *) ap_get_module_config(r->server->module_config,
                                                      &jk_module);
    JK_TRACE_ENTER(xconf->log);
    if (apr_table_get(r->subprocess_env, "no-jk")) {
        if (JK_IS_DEBUG_LEVEL(xconf->log))
            jk_log(xconf->log, JK_LOG_DEBUG,
                   "Into handler no-jk env var detected for uri=%s, declined",
                   r->uri);

        JK_TRACE_EXIT(xconf->log);
        return DECLINED;
    }

    /* Was the option to forward directories to Tomcat set? */
    if (!dmt && !(xconf->options & JK_OPT_FWDDIRS)) {
        JK_TRACE_EXIT(xconf->log);
        return DECLINED;
    }

    worker_name = apr_table_get(r->notes, JK_NOTE_WORKER_NAME);

    if (worker_name == NULL) {
        /* we may be here because of a manual directive ( that overrides
           translate and
           sets the handler directly ). We still need to know the worker.
         */
        worker_name = apr_table_get(r->subprocess_env, xconf->worker_indicator);
        if (worker_name) {
          /* The JkWorkerIndicator environment variable has
           * been used to explicitely set the worker without JkMount.
           * This is useful in combination with LocationMatch or mod_rewrite.
           */
            if (JK_IS_DEBUG_LEVEL(xconf->log))
                jk_log(xconf->log, JK_LOG_DEBUG,
                       "Retrieved worker (%s) from env %s for %s",
                       worker_name, xconf->worker_indicator, r->uri);
            if (ap_strchr_c(worker_name, ';')) {
                rule_extension_t *e = apr_palloc(r->pool, sizeof(rule_extension_t));
                char *w = apr_pstrdup(r->pool, worker_name);
                worker_name_extension = JK_TRUE;
                parse_rule_extensions(w, e, xconf->log);
                worker_name = w;
                rconf = (jk_request_conf_t *)ap_get_module_config(r->request_config,
                                                                  &jk_module);
                rconf->rule_extensions = e;
            }
        }
        else if (worker_env.num_of_workers == 1) {
          /** We have a single worker ( the common case ).
              ( lb is a bit special, it should count as a single worker but
              I'm not sure how ). We also have a manual config directive that
              explicitely give control to us. */
            worker_name = worker_env.worker_list[0];
            if (JK_IS_DEBUG_LEVEL(xconf->log))
                jk_log(xconf->log, JK_LOG_DEBUG,
                       "Single worker (%s) configuration for %s",
                       worker_name, r->uri);
        }
        else {
            if (!xconf->uw_map) {
                if (JK_IS_DEBUG_LEVEL(xconf->log))
                    jk_log(xconf->log, JK_LOG_DEBUG,
                           "missing uri map for %s:%s",
                           xconf->s->server_hostname ? xconf->s->server_hostname : "_default_",
                           r->uri);
            }
            else {
                rule_extension_t *e;
                worker_name = map_uri_to_worker_ext(xconf->uw_map, r->uri,
                                                    NULL, &e, NULL, xconf->log);
                rconf = (jk_request_conf_t *)ap_get_module_config(r->request_config,
                                                                  &jk_module);
                rconf->rule_extensions = e;
            }

            if (worker_name == NULL && worker_env.num_of_workers) {
                worker_name = worker_env.worker_list[0];
                if (JK_IS_DEBUG_LEVEL(xconf->log))
                    jk_log(xconf->log, JK_LOG_DEBUG,
                           "Using first worker (%s) from %d workers for %s",
                           worker_name, worker_env.num_of_workers, r->uri);
            }
        }
        if (worker_name)
            apr_table_setn(r->notes, JK_NOTE_WORKER_NAME, worker_name);
    }

    if (JK_IS_DEBUG_LEVEL(xconf->log))
       jk_log(xconf->log, JK_LOG_DEBUG, "Into handler %s worker=%s"
              " r->proxyreq=%d",
              r->handler, STRNULL_FOR_NULL(worker_name), r->proxyreq);

    rconf = (jk_request_conf_t *)ap_get_module_config(r->request_config,
                                                      &jk_module);
    rconf->jk_handled = JK_TRUE;

    /* If this is a proxy request, we'll notify an error */
    if (r->proxyreq) {
        jk_log(xconf->log, JK_LOG_INFO, "Proxy request for worker=%s"
              " is not allowed",
              STRNULL_FOR_NULL(worker_name));
        JK_TRACE_EXIT(xconf->log);
        return HTTP_INTERNAL_SERVER_ERROR;
    }

    /* Set up r->read_chunked flags for chunked encoding, if present */
    if ((rc = ap_setup_client_block(r, REQUEST_CHUNKED_DECHUNK)) != APR_SUCCESS) {
        JK_TRACE_EXIT(xconf->log);
        return rc;
    }

    if (worker_name) {
        jk_worker_t *worker = wc_get_worker_for_name(worker_name, xconf->log);

        /* If the remote client has aborted, just ignore the request */
        if (r->connection->aborted) {
            jk_log(xconf->log, JK_LOG_INFO, "Client connection aborted for"
                   " worker=%s",
                   worker_name);
            JK_TRACE_EXIT(xconf->log);
            return OK;
        }

        if (worker) {
            long micro, seconds;
            char *duration = NULL;
            apr_time_t rd;
            apr_time_t request_begin = 0;
            int is_error = HTTP_INTERNAL_SERVER_ERROR;
            int rc = JK_FALSE;
            apache_private_data_t private_data;
            jk_ws_service_t s;
            jk_pool_atom_t buf[SMALL_POOL_SIZE];
            jk_open_pool(&private_data.p, buf, sizeof(buf));

            private_data.read_body_started = JK_FALSE;
            private_data.r = r;

            if (worker_name_extension == JK_TRUE) {
                extension_fix(&private_data.p, worker_name,
                              rconf->rule_extensions, xconf->log);
            }

            /* Maintain will be done by watchdog thread */
            if (!jk_watchdog_interval)
                wc_maintain(xconf->log);
            jk_init_ws_service(&s);
            s.ws_private = &private_data;
            s.pool = &private_data.p;
            apr_table_setn(r->notes, JK_NOTE_WORKER_TYPE,
                           wc_get_name_for_type(worker->type, xconf->log));

            request_begin = apr_time_now();

            if (init_ws_service(&private_data, &s, xconf)) {
                jk_endpoint_t *end = NULL;

                /* Use per/thread pool ( or "context" ) to reuse the
                   endpoint. It's a bit faster, but I don't know
                   how to deal with load balancing - but it's usefull for JNI
                 */

                /* worker->get_endpoint might fail if we are out of memory so check */
                /* and handle it */
                if (worker->get_endpoint(worker, &end, xconf->log)) {
                    rc = end->service(end, &s, xconf->log,
                                      &is_error);
                    end->done(&end, xconf->log);
                    if (s.content_read < s.content_length ||
                        (s.is_chunked && !s.no_more_chunks)) {
                        /*
                         * If the servlet engine didn't consume all of the
                         * request data, consume and discard all further
                         * characters left to read from client
                         */
                        char *buff = apr_palloc(r->pool, 2048);
                        int consumed = 0;
                        if (buff != NULL) {
                            int rd;
                            while ((rd =
                                    ap_get_client_block(r, buff, 2048)) > 0) {
                                s.content_read += rd;
                                consumed += rd;
                            }
                        }
                        if (JK_IS_DEBUG_LEVEL(xconf->log)) {
                           jk_log(xconf->log, JK_LOG_DEBUG,
                                  "Consumed %d bytes of remaining request data for worker=%s",
                                  consumed, STRNULL_FOR_NULL(worker_name));
                        }
                    }
                }
                else {            /* this means we couldn't get an endpoint */
                    jk_log(xconf->log, JK_LOG_ERROR, "Could not get endpoint"
                           " for worker=%s",
                           worker_name);
                    rc = 0;       /* just to make sure that we know we've failed */
                }
            }
            else {
                jk_log(xconf->log, JK_LOG_ERROR, "Could not init service"
                       " for worker=%s",
                       worker_name);
                jk_close_pool(&private_data.p);
                JK_TRACE_EXIT(xconf->log);
                return HTTP_INTERNAL_SERVER_ERROR;
            }
            rd = apr_time_now() - request_begin;
            seconds = (long)apr_time_sec(rd);
            micro = (long)(rd - apr_time_from_sec(seconds));

            duration = apr_psprintf(r->pool, "%.1ld.%.6ld", seconds, micro);
            apr_table_setn(r->notes, JK_NOTE_REQUEST_DURATION, duration);
            if (s.route && *s.route)
                apr_table_setn(r->notes, JK_NOTE_WORKER_ROUTE, s.route);

            jk_close_pool(&private_data.p);

            if (rc > 0) {
                if (s.extension.use_server_error_pages &&
                    s.http_response_status >= s.extension.use_server_error_pages) {
                    if (JK_IS_DEBUG_LEVEL(xconf->log))
                        jk_log(xconf->log, JK_LOG_DEBUG, "Forwarding status=%d"
                               " for worker=%s",
                               s.http_response_status, worker_name);
                    JK_TRACE_EXIT(xconf->log);
                    return s.http_response_status;
                }
                /* If tomcat returned no body and the status is not OK,
                   let apache handle the error code */

                if (!r->sent_bodyct && r->status >= HTTP_BAD_REQUEST) {
                    jk_log(xconf->log, JK_LOG_INFO, "No body with status=%d"
                           " for worker=%s",
                           r->status, worker_name);
                    JK_TRACE_EXIT(xconf->log);
                    return r->status;
                }
                if (JK_IS_DEBUG_LEVEL(xconf->log))
                    jk_log(xconf->log, JK_LOG_DEBUG, "Service finished"
                           " with status=%d for worker=%s",
                           r->status, worker_name);
                JK_TRACE_EXIT(xconf->log);
                return OK;      /* NOT r->status, even if it has changed. */
            }
            else if (rc == JK_CLIENT_ERROR) {
                if (is_error != HTTP_REQUEST_ENTITY_TOO_LARGE)
                    r->connection->aborted = 1;
                jk_log(xconf->log, JK_LOG_INFO, "Aborting connection"
                       " for worker=%s",
                       worker_name);
                JK_TRACE_EXIT(xconf->log);
                return is_error;
            }
            else {
                jk_log(xconf->log, JK_LOG_INFO, "Service error=%d"
                       " for worker=%s",
                       rc, worker_name);
                JK_TRACE_EXIT(xconf->log);
                return is_error;
            }
        }
        else {
            jk_log(xconf->log, JK_LOG_INFO, "Could not find a worker"
                   " for worker name=%s",
                   worker_name);
            JK_TRACE_EXIT(xconf->log);
            return HTTP_INTERNAL_SERVER_ERROR;
        }
    }

    rconf->jk_handled = JK_FALSE;
    JK_TRACE_EXIT(xconf->log);
    return DECLINED;
}