mod_serf.c revision 3c290fd0361d6d9d84d97725eaf299456bddd6cf
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "mod_serf.h"
#include "httpd.h"
#include "http_core.h"
#include "http_config.h"
#include "http_protocol.h"
#include "http_request.h"
#include "http_log.h"
#include "serf.h"
#include "apr_uri.h"
#include "apr_strings.h"
#include "apr_version.h"
#include "ap_mpm.h"
module AP_MODULE_DECLARE_DATA serf_module;
static int mpm_supprts_serf = 0;
typedef struct {
int on;
int preservehost;
apr_uri_t url;
} serf_config_t;
typedef struct {
const char *name;
const char *provider;
apr_table_t *params;
} serf_cluster_t;
typedef struct {
/* name -> serf_cluster_t* */
apr_hash_t *clusters;
} serf_server_config_t;
typedef struct {
int rstatus;
int want_ssl;
int done_headers;
int keep_reading;
request_rec *r;
apr_pool_t *serf_pool;
apr_bucket_brigade *tmpbb;
serf_config_t *conf;
serf_ssl_context_t *ssl_ctx;
serf_bucket_alloc_t *bkt_alloc;
serf_bucket_t *body_bkt;
} s_baton_t;
#if !APR_VERSION_AT_LEAST(1,4,0)
#define apr_time_from_msec(x) (x * 1000)
#endif
/**
* This works right now because all timers are invoked in the single listener
* thread in the Event MPM -- the same thread that serf callbacks are made
* from, so we don't technically need a mutex yet, but with the Simple MPM,
* invocations are made from worker threads, and we need to figure out locking
*/
static void timed_cleanup_callback(void *baton)
{
s_baton_t *ctx = baton;
/* Causes all serf connections to unregister from the event mpm */
if (ctx->rstatus) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, ctx->rstatus, ctx->r,
"serf: request returned: %d", ctx->rstatus);
ctx->r->status = HTTP_OK;
apr_pool_destroy(ctx->serf_pool);
ap_die(ctx->rstatus, ctx->r);
}
else {
apr_bucket *e;
apr_brigade_cleanup(ctx->tmpbb);
e = apr_bucket_flush_create(ctx->r->connection->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(ctx->tmpbb, e);
e = apr_bucket_eos_create(ctx->r->connection->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(ctx->tmpbb, e);
/* TODO: return code? bleh */
ap_pass_brigade(ctx->r->output_filters, ctx->tmpbb);
apr_pool_destroy(ctx->serf_pool);
ap_finalize_request_protocol(ctx->r);
ap_process_request_after_handler(ctx->r);
return;
}
}
static void closed_connection(serf_connection_t *conn,
void *closed_baton,
apr_status_t why,
apr_pool_t *pool)
{
s_baton_t *ctx = closed_baton;
if (why) {
/* justin says that error handling isn't done yet. hah. */
/* XXXXXX: review */
ap_log_rerror(APLOG_MARK, APLOG_ERR, why, ctx->r, "Closed Connection Error");
ctx->rstatus = HTTP_INTERNAL_SERVER_ERROR;
}
if (mpm_supprts_serf) {
ap_mpm_register_timed_callback(apr_time_from_msec(1),
timed_cleanup_callback, ctx);
}
ctx->keep_reading = 0;
}
static serf_bucket_t* conn_setup(apr_socket_t *sock,
void *setup_baton,
apr_pool_t *pool)
{
serf_bucket_t *c;
s_baton_t *ctx = setup_baton;
c = serf_bucket_socket_create(sock, ctx->bkt_alloc);
if (ctx->want_ssl) {
c = serf_bucket_ssl_decrypt_create(c, ctx->ssl_ctx, ctx->bkt_alloc);
}
return c;
}
static int copy_headers_in(void *vbaton, const char *key, const char *value)
{
serf_bucket_t *hdrs_bkt = (serf_bucket_t *)vbaton;
/* XXXXX: List of headers not to copy to serf. serf's serf_bucket_headers_setn,
* doesn't actually overwrite a header if we set it once, so we need to ignore anything
* we might want to toggle or combine.
*/
switch (key[0]) {
case 'a':
case 'A':
if (strcasecmp("Accept-Encoding", key) == 0) {
return 0;
}
break;
case 'c':
case 'C':
if (strcasecmp("Connection", key) == 0) {
return 0;
}
break;
case 'h':
case 'H':
if (strcasecmp("Host", key) == 0) {
return 0;
}
break;
case 'k':
case 'K':
if (strcasecmp("Keep-Alive", key) == 0) {
return 0;
}
break;
case 't':
case 'T':
if (strcasecmp("TE", key) == 0) {
return 0;
}
if (strcasecmp("Trailer", key) == 0) {
return 0;
}
break;
case 'u':
case 'U':
if (strcasecmp("Upgrade", key) == 0) {
return 0;
}
break;
default:
break;
}
serf_bucket_headers_setn(hdrs_bkt, key, value);
return 0;
}
static int copy_headers_out(void *vbaton, const char *key, const char *value)
{
s_baton_t *ctx = vbaton;
int done = 0;
/* XXXXX: Special Treatment required for MANY other headers. fixme.*/
switch (key[0]) {
case 'c':
case 'C':
if (strcasecmp("Content-Type", key) == 0) {
ap_set_content_type(ctx->r, value);
done = 1;
break;
}
else if (strcasecmp("Connection", key) == 0) {
done = 1;
break;
}
else if (strcasecmp("Content-Encoding", key) == 0) {
done = 1;
break;
}
else if (strcasecmp("Content-Length", key) == 0) {
done = 1;
break;
}
break;
case 't':
case 'T':
if (strcasecmp("Transfer-Encoding", key) == 0) {
done = 1;
break;
}
break;
default:
break;
}
if (!done) {
apr_table_addn(ctx->r->headers_out, key, value);
}
return 0;
}
static serf_bucket_t* accept_response(serf_request_t *request,
serf_bucket_t *stream,
void *acceptor_baton,
apr_pool_t *pool)
{
serf_bucket_t *c;
serf_bucket_alloc_t *bkt_alloc;
/* get the per-request bucket allocator */
bkt_alloc = serf_request_get_alloc(request);
/* Create a barrier so the response doesn't eat us! */
c = serf_bucket_barrier_create(stream, bkt_alloc);
return serf_bucket_response_create(c, bkt_alloc);
}
static apr_status_t handle_response(serf_request_t *request,
serf_bucket_t *response,
void *vbaton,
apr_pool_t *pool)
{
apr_status_t rv;
s_baton_t *ctx = vbaton;
const char *data;
apr_size_t len;
serf_status_line sl;
if (response == NULL) {
ctx->rstatus = HTTP_INTERNAL_SERVER_ERROR;
return APR_EGENERAL;
}
/* XXXXXXX: Create better error message. */
rv = serf_bucket_response_status(response, &sl);
if (rv) {
if (APR_STATUS_IS_EAGAIN(rv)) {
return APR_SUCCESS;
}
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, ctx->r, "serf_bucket_response_status...");
ctx->rstatus = HTTP_INTERNAL_SERVER_ERROR;
if (mpm_supprts_serf) {
ap_mpm_register_timed_callback(apr_time_from_msec(1),
timed_cleanup_callback, ctx);
}
return rv;
}
/**
* XXXXX: If I understood serf buckets better, it might be possible to not
* copy all of the data here, and better stream it to the client.
**/
do {
apr_brigade_cleanup(ctx->tmpbb);
rv = serf_bucket_read(response, AP_IOBUFSIZE, &data, &len);
if (SERF_BUCKET_READ_ERROR(rv)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, ctx->r, "serf_bucket_read(response)");
return rv;
}
if (!ctx->done_headers) {
serf_bucket_t *hdrs;
serf_status_line line;
/* TODO: improve */
serf_bucket_response_status(response, &line);
ctx->r->status = line.code;
hdrs = serf_bucket_response_get_headers(response);
serf_bucket_headers_do(hdrs, copy_headers_out, ctx);
ctx->done_headers = 1;
}
if (len > 0) {
/* TODO: make APR bucket <-> serf bucket stuff more magical. */
apr_brigade_write(ctx->tmpbb, NULL, NULL, data, len);
}
if (APR_STATUS_IS_EOF(rv)) {
ctx->keep_reading = 0;
ctx->rstatus = ap_pass_brigade(ctx->r->output_filters, ctx->tmpbb);
if (mpm_supprts_serf) {
ap_mpm_register_timed_callback(apr_time_from_msec(1),
timed_cleanup_callback, ctx);
}
return APR_EOF;
}
ctx->rstatus = ap_pass_brigade(ctx->r->output_filters, ctx->tmpbb);
/* XXXX: Should we send a flush now? */
if (APR_STATUS_IS_EAGAIN(rv)) {
return APR_SUCCESS;
}
} while (1);
}
static apr_status_t setup_request(serf_request_t *request,
void *vbaton,
serf_bucket_t **req_bkt,
serf_response_acceptor_t *acceptor,
void **acceptor_baton,
serf_response_handler_t *handler,
void **handler_baton,
apr_pool_t *pool)
{
s_baton_t *ctx = vbaton;
serf_bucket_t *hdrs_bkt;
*req_bkt = serf_bucket_request_create(ctx->r->method, ctx->r->unparsed_uri,
ctx->body_bkt,
serf_request_get_alloc(request));
hdrs_bkt = serf_bucket_request_get_headers(*req_bkt);
apr_table_do(copy_headers_in, hdrs_bkt, ctx->r->headers_in, NULL);
if (ctx->conf->preservehost) {
serf_bucket_headers_setn(hdrs_bkt, "Host",
apr_table_get(ctx->r->headers_in, "Host"));
}
else {
serf_bucket_headers_setn(hdrs_bkt, "Host", ctx->conf->url.hostname);
}
serf_bucket_headers_setn(hdrs_bkt, "Accept-Encoding", "gzip");
if (ctx->want_ssl) {
if (ctx->ssl_ctx == NULL) {
*req_bkt = serf_bucket_ssl_encrypt_create(*req_bkt, NULL,
ctx->bkt_alloc);
ctx->ssl_ctx = serf_bucket_ssl_encrypt_context_get(*req_bkt);
}
else {
*req_bkt = serf_bucket_ssl_encrypt_create(*req_bkt, ctx->ssl_ctx,
ctx->bkt_alloc);
}
}
*acceptor = accept_response;
*acceptor_baton = ctx;
*handler = handle_response;
*handler_baton = ctx;
return APR_SUCCESS;
}
/*
* Finding a random number in a range.
* n' = a + n(b-a+1)/(M+1)
* where:
* n' = random number in range
* a = low end of range
* b = high end of range
* n = random number of 0..M
* M = maxint
* Algorithm 'borrowed' from PHP's rand() function. (See mod_lbmethod_heartbeat.c).
*/
#define RAND_RANGE(__n, __min, __max, __tmax) \
(__n) = (__min) + (long) ((double) ((__max) - (__min) + 1.0) * ((__n) / ((__tmax) + 1.0)))
static apr_status_t random_pick(apr_uint32_t *number,
apr_uint32_t min,
apr_uint32_t max)
{
apr_status_t rv =
apr_generate_random_bytes((void*)number, sizeof(apr_uint32_t));
if (rv) {
return rv;
}
RAND_RANGE(*number, min, max, APR_UINT32_MAX);
return APR_SUCCESS;
}
/* TOOD: rewrite drive_serf to make it async */
static int drive_serf(request_rec *r, serf_config_t *conf)
{
apr_status_t rv = 0;
apr_pool_t *pool;
apr_sockaddr_t *address;
s_baton_t *baton = apr_palloc(r->pool, sizeof(s_baton_t));
/* XXXXX: make persistent/per-process or something.*/
serf_context_t *serfme;
serf_connection_t *conn;
serf_server_config_t *ctx =
(serf_server_config_t *)ap_get_module_config(r->server->module_config,
&serf_module);
/* Allocate everything out of a subpool, with a shorter lifetime than
* the main request, so that we can cleanup safely and remove our events
* from the main serf context in the async mpm mode.
*/
apr_pool_create(&pool, r->pool);
if (strcmp(conf->url.scheme, "cluster") == 0) {
int rc;
ap_serf_cluster_provider_t *cp;
serf_cluster_t *cluster;
apr_array_header_t *servers = NULL;
apr_uint32_t pick = 0;
ap_serf_server_t *choice;
/* TODO: could this be optimized in post-config to pre-setup the
* pointers to the right cluster inside the conf structure?
*/
cluster = apr_hash_get(ctx->clusters,
conf->url.hostname,
APR_HASH_KEY_STRING);
if (!cluster) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
"SerfCluster: unable to find cluster %s", conf->url.hostname);
return HTTP_INTERNAL_SERVER_ERROR;
}
cp = ap_lookup_provider(AP_SERF_CLUSTER_PROVIDER, cluster->provider, "0");
if (cp == NULL) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
"SerfCluster: unable to find provider %s", cluster->provider);
return HTTP_INTERNAL_SERVER_ERROR;
}
if (cp->list_servers == NULL) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
"SerfCluster: %s is missing list servers provider.", cluster->provider);
return HTTP_INTERNAL_SERVER_ERROR;
}
rc = cp->list_servers(cp->baton,
r,
cluster->params,
&servers);
if (rc != OK) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r,
"SerfCluster: %s list servers returned failure", cluster->provider);
return HTTP_INTERNAL_SERVER_ERROR;
}
if (servers == NULL || apr_is_empty_array(servers)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r,
"SerfCluster: %s failed to provide a list of servers", cluster->provider);
return HTTP_INTERNAL_SERVER_ERROR;
}
/* TOOD: restructure try all servers in the array !! */
if (random_pick(&pick, 0, servers->nelts-1) != APR_SUCCESS)
pick = 0;
choice = APR_ARRAY_IDX(servers, pick, ap_serf_server_t *);
rv = apr_sockaddr_info_get(&address, choice->ip,
APR_UNSPEC, choice->port, 0,
pool);
}
else {
/* XXXXX: cache dns? */
rv = apr_sockaddr_info_get(&address, conf->url.hostname,
APR_UNSPEC, conf->url.port, 0,
pool);
}
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, "Unable to resolve: %s", conf->url.hostname);
return HTTP_INTERNAL_SERVER_ERROR;
}
if (mpm_supprts_serf) {
serfme = ap_lookup_provider("mpm_serf", "instance", "0");
if (!serfme) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, "mpm lied to us about supporting serf.");
return HTTP_INTERNAL_SERVER_ERROR;
}
}
else {
serfme = serf_context_create(pool);
}
baton->r = r;
baton->conf = conf;
baton->serf_pool = pool;
baton->bkt_alloc = serf_bucket_allocator_create(pool, NULL, NULL);
baton->body_bkt = NULL;
baton->ssl_ctx = NULL;
baton->rstatus = OK;
baton->tmpbb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
baton->done_headers = 0;
baton->keep_reading = 1;
if (strcasecmp(conf->url.scheme, "https") == 0) {
baton->want_ssl = 1;
}
else {
baton->want_ssl = 0;
}
rv = ap_setup_client_block(baton->r, REQUEST_CHUNKED_DECHUNK);
if (rv) {
return rv;
}
/* TODO: create custom serf bucket, which does async request body reads */
if (ap_should_client_block(r)) {
apr_size_t len;
apr_off_t flen = 0;
char buf[AP_IOBUFSIZE];
apr_file_t *fp;
rv = apr_file_mktemp(&fp, "mod_serf_buffer.XXXXXX", 0, pool);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, "mod_serf: Unable to create temp request body buffer file.");
return HTTP_INTERNAL_SERVER_ERROR;
}
do {
len = sizeof(buf);
rv = ap_get_client_block(baton->r, buf, len);
if (rv > 0) {
rv = apr_file_write_full(fp, buf, rv, NULL);
if (rv) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, "mod_serf: failed to read request body");
return HTTP_INTERNAL_SERVER_ERROR;
}
}
} while(rv > 0);
if (rv < 0) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, "mod_serf: failed to read request body");
return HTTP_INTERNAL_SERVER_ERROR;
}
apr_file_seek(fp, APR_SET, &flen);
baton->body_bkt = serf_bucket_file_create(fp, baton->bkt_alloc);
}
conn = serf_connection_create(serfme, address,
conn_setup, baton,
closed_connection, baton,
pool);
/* XXX: Is it correct that we don't use the returned serf_request_t? */
serf_connection_request_create(conn, setup_request, baton);
if (mpm_supprts_serf) {
return SUSPENDED;
}
else {
do {
rv = serf_context_run(serfme, SERF_DURATION_FOREVER, pool);
/* XXXX: Handle timeouts */
if (APR_STATUS_IS_TIMEUP(rv)) {
continue;
}
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, "serf_context_run() for %pI", address);
return HTTP_INTERNAL_SERVER_ERROR;
}
serf_debug__closed_conn(baton->bkt_alloc);
} while (baton->keep_reading);
return baton->rstatus;
}
}
static int serf_handler(request_rec *r)
{
serf_config_t *conf = ap_get_module_config(r->per_dir_config,
&serf_module);
if (conf->on == 0) {
return DECLINED;
}
return drive_serf(r, conf);
}
static int is_true(const char *w)
{
if (strcasecmp(w, "on") == 0 || strcmp(w, "1") == 0 ||
strcasecmp(w, "true") == 0)
{
return 1;
}
return 0;
}
static const char *add_pass(cmd_parms *cmd, void *vconf,
int argc, char *const argv[])
{
int i;
apr_status_t rv;
serf_config_t *conf = (serf_config_t *) vconf;
if (argc < 1) {
return "SerfPass must have at least a URI.";
}
rv = apr_uri_parse(cmd->pool, argv[0], &conf->url);
if (rv != APR_SUCCESS) {
return "mod_serf: Unable to parse SerfPass url.";
}
if (!conf->url.scheme) {
return "mod_serf: Need scheme part in url.";
}
/* XXXX: These are bugs in apr_uri_parse. Fixme. */
if (!conf->url.port) {
conf->url.port = apr_uri_port_of_scheme(conf->url.scheme);
}
if (!conf->url.path) {
conf->url.path = "/";
}
for (i = 1; i < argc; i++) {
const char *p = argv[i];
const char *x = ap_strchr_c(p, '=');
if (x) {
if (strncmp(p, "preservehost", x-p) == 0) {
conf->preservehost = is_true(x+1);
}
}
}
conf->on = 1;
return NULL;
}
/* SerfCluster <name> <provider> <key=value_params_to_provider> ... */
static const char *add_cluster(cmd_parms *cmd, void *d,
int argc, char *const argv[])
{
const char *rv;
ap_serf_cluster_provider_t *backend;
int i;
serf_cluster_t *cluster = NULL;
serf_server_config_t *ctx =
(serf_server_config_t *)ap_get_module_config(cmd->server->module_config,
&serf_module);
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
if (argc < 2) {
return "SerfCluster must have at least a name and provider.";
}
cluster = apr_palloc(cmd->pool, sizeof(serf_cluster_t));
cluster->name = apr_pstrdup(cmd->pool, argv[0]);
cluster->provider = apr_pstrdup(cmd->pool, argv[1]);
cluster->params = apr_table_make(cmd->pool, 6);
backend = ap_lookup_provider(AP_SERF_CLUSTER_PROVIDER, cluster->provider, "0");
if (backend == NULL) {
return apr_psprintf(cmd->pool, "SerfCluster: unable to find "
"provider '%s'", cluster->provider);
}
for (i = 2; i < argc; i++) {
const char *p = argv[i];
const char *x = ap_strchr_c(p, '=');
if (x && strlen(p) > 1) {
apr_table_addn(cluster->params,
apr_pstrndup(cmd->pool, p, x-p),
x+1);
}
else {
apr_table_addn(cluster->params,
apr_pstrdup(cmd->pool, p),
"");
}
}
if (backend->check_config == NULL) {
return apr_psprintf(cmd->pool, "SerfCluster: Provider '%s' failed to "
"provider a configuration checker",
cluster->provider);
}
rv = backend->check_config(backend->baton, cmd, cluster->params);
if (rv) {
return rv;
}
apr_hash_set(ctx->clusters, cluster->name, APR_HASH_KEY_STRING, cluster);
return NULL;
}
static void *create_dir_config(apr_pool_t *p, char *dummy)
{
serf_config_t *new = (serf_config_t *) apr_pcalloc(p, sizeof(serf_config_t));
new->on = 0;
new->preservehost = 1;
return new;
}
static void *create_server_config(apr_pool_t *p, server_rec *s)
{
serf_server_config_t *ctx =
(serf_server_config_t *) apr_pcalloc(p, sizeof(serf_server_config_t));
ctx->clusters = apr_hash_make(p);
return ctx;
}
static void * merge_server_config(apr_pool_t *p, void *basev, void *overridesv)
{
serf_server_config_t *ctx = apr_pcalloc(p, sizeof(serf_server_config_t));
serf_server_config_t *base = (serf_server_config_t *) basev;
serf_server_config_t *overrides = (serf_server_config_t *) overridesv;
ctx->clusters = apr_hash_overlay(p, base->clusters, overrides->clusters);
return ctx;
}
static const command_rec serf_cmds[] =
{
AP_INIT_TAKE_ARGV("SerfCluster", add_cluster, NULL, RSRC_CONF,
"Configure a cluster backend"),
AP_INIT_TAKE_ARGV("SerfPass", add_pass, NULL, OR_INDEXES,
"URL to reverse proxy to"),
{NULL}
};
typedef struct hb_table_baton_t {
apr_pool_t *p;
const char *msg;
} hb_table_baton_t;
static int hb_table_check(void *rec, const char *key, const char *value)
{
hb_table_baton_t *b = (hb_table_baton_t*)rec;
if (strcmp(key, "path") != 0) {
b->msg = apr_psprintf(b->p,
"SerfCluster Heartbeat Invalid parameter '%s'",
key);
return 1;
}
return 0;
}
static const char* hb_config_check(void *baton,
cmd_parms *cmd,
apr_table_t *params)
{
hb_table_baton_t b;
if (apr_is_empty_table(params)) {
return "SerfCluster Heartbeat requires a path to the heartbat information.";
}
b.p = cmd->pool;
b.msg = NULL;
apr_table_do(hb_table_check, &b, params, NULL);
if (b.msg) {
return b.msg;
}
return NULL;
}
typedef struct hb_server_t {
const char *ip;
int busy;
int ready;
int seen;
unsigned int port;
} hb_server_t;
static void
argstr_to_table(apr_pool_t *p, char *str, apr_table_t *parms)
{
char *key;
char *value;
char *strtok_state;
key = apr_strtok(str, "&", &strtok_state);
while (key) {
value = strchr(key, '=');
if (value) {
*value = '\0'; /* Split the string in two */
value++; /* Skip passed the = */
}
else {
value = "1";
}
ap_unescape_url(key);
ap_unescape_url(value);
apr_table_set(parms, key, value);
key = apr_strtok(NULL, "&", &strtok_state);
}
}
static apr_status_t read_heartbeats(const char *path,
apr_array_header_t *servers,
apr_pool_t *pool)
{
apr_finfo_t fi;
apr_status_t rv;
apr_file_t *fp;
if (!path) {
return APR_SUCCESS;
}
rv = apr_file_open(&fp, path, APR_READ|APR_BINARY|APR_BUFFERED,
APR_OS_DEFAULT, pool);
if (rv) {
return rv;
}
rv = apr_file_info_get(&fi, APR_FINFO_SIZE, fp);
if (rv) {
return rv;
}
{
char *t;
int lineno = 0;
apr_table_t *hbt = apr_table_make(pool, 10);
char buf[4096];
while (apr_file_gets(buf, sizeof(buf), fp) == APR_SUCCESS) {
hb_server_t *server;
const char *ip;
lineno++;
/* comment */
if (buf[0] == '#') {
continue;
}
/* line format: <IP> <query_string>\n */
t = strchr(buf, ' ');
if (!t) {
continue;
}
ip = apr_pstrndup(pool, buf, t - buf);
t++;
server = apr_pcalloc(pool, sizeof(hb_server_t));
server->ip = ip;
server->port = 80;
server->seen = -1;
apr_table_clear(hbt);
argstr_to_table(pool, apr_pstrdup(pool, t), hbt);
if (apr_table_get(hbt, "busy")) {
server->busy = atoi(apr_table_get(hbt, "busy"));
}
if (apr_table_get(hbt, "ready")) {
server->ready = atoi(apr_table_get(hbt, "ready"));
}
if (apr_table_get(hbt, "lastseen")) {
server->seen = atoi(apr_table_get(hbt, "lastseen"));
}
if (apr_table_get(hbt, "port")) {
server->port = atoi(apr_table_get(hbt, "port"));
}
if (server->busy == 0 && server->ready != 0) {
/* Server has zero threads active, but lots of them ready,
* it likely just started up, so lets /4 the number ready,
* to prevent us from completely flooding it with all new
* requests.
*/
server->ready = server->ready / 4;
}
APR_ARRAY_PUSH(servers, hb_server_t *) = server;
}
}
return APR_SUCCESS;
}
static int hb_server_sort(const void *a_, const void *b_)
{
hb_server_t *a = (hb_server_t*)a_;
hb_server_t *b = (hb_server_t*)b_;
if (a->ready == b->ready) {
return 0;
}
else if (a->ready > b->ready) {
return -1;
}
else {
return 1;
}
}
static int hb_list_servers(void *baton,
request_rec *r,
apr_table_t *params,
apr_array_header_t **out_servers)
{
int i;
hb_server_t *hbs;
apr_status_t rv;
apr_pool_t *tpool;
apr_array_header_t *tmpservers;
apr_array_header_t *servers;
const char *path = apr_table_get(params, "path");
apr_pool_create(&tpool, r->pool);
path = ap_server_root_relative(tpool, path);
tmpservers = apr_array_make(tpool, 32, sizeof(hb_server_t *));
rv = read_heartbeats(path, tmpservers, tpool);
if (rv) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
"SerfCluster: Heartbeat unable to read '%s'", path);
apr_pool_destroy(tpool);
return HTTP_INTERNAL_SERVER_ERROR;
}
qsort(tmpservers->elts, tmpservers->nelts, sizeof(hb_server_t *),
hb_server_sort);
servers = apr_array_make(r->pool, tmpservers->nelts, sizeof(ap_serf_server_t *));
for (i = 0;
i < tmpservers->nelts;
i++)
{
ap_serf_server_t *x;
hbs = APR_ARRAY_IDX(tmpservers, i, hb_server_t *);
if (hbs->ready > 0) {
x = apr_palloc(r->pool, sizeof(ap_serf_server_t));
x->ip = apr_pstrdup(r->pool, hbs->ip);
x->port = hbs->port;
APR_ARRAY_PUSH(servers, ap_serf_server_t *) = x;
}
}
*out_servers = servers;
apr_pool_destroy(tpool);
return OK;
}
static const ap_serf_cluster_provider_t builtin_heartbeat =
{
"heartbeat",
NULL,
&hb_config_check,
&hb_list_servers,
NULL,
NULL
};
static int static_table_check(void *rec, const char *key, const char *value)
{
hb_table_baton_t *b = (hb_table_baton_t*)rec;
if (strcmp(key, "hosts") != 0 &&
strcmp(key, "order") != 0) {
b->msg = apr_psprintf(b->p,
"SerfCluster Static Invalid parameter '%s'",
key);
return 1;
}
return 0;
}
static const char* static_config_check(void *baton,
cmd_parms *cmd,
apr_table_t *params)
{
hb_table_baton_t b;
if (apr_is_empty_table(params)) {
return "SerfCluster Static requires at least a host list.";
}
b.p = cmd->pool;
b.msg = NULL;
apr_table_do(static_table_check, &b, params, NULL);
if (b.msg) {
return b.msg;
}
if (apr_table_get(params, "hosts") == NULL) {
return "SerfCluster Static requires at least a hosts parameter";
}
return NULL;
}
static int static_list_servers(void *baton,
request_rec *r,
apr_table_t *params,
apr_array_header_t **out_servers)
{
apr_status_t rv;
char *ip;
char *strtok_state;
apr_array_header_t *servers;
const char *hosts = apr_table_get(params, "hosts");
const char *order = apr_table_get(params, "order");
servers = apr_array_make(r->pool, 10, sizeof(ap_serf_server_t *));
ip = apr_strtok(apr_pstrdup(r->pool, hosts), ",", &strtok_state);
while (ip) {
char *host_str;
char *scope_id;
apr_port_t port = 0;
rv = apr_parse_addr_port(&host_str, &scope_id, &port, ip, r->pool);
if (!rv) {
ap_serf_server_t *s = apr_palloc(r->pool, sizeof(ap_serf_server_t));
s->ip = host_str;
s->port = port ? port : 80;
APR_ARRAY_PUSH(servers, ap_serf_server_t *) = s;
}
ip = apr_strtok(NULL, ",", &strtok_state);
}
if (strcmp(order, "random") == 0) {
/* TODO: support order=random */
}
*out_servers = servers;
return OK;
}
static const ap_serf_cluster_provider_t builtin_static =
{
"static",
NULL,
&static_config_check,
&static_list_servers,
NULL,
NULL
};
static int serf_post_config(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s)
{
apr_status_t rv;
rv = ap_mpm_query(AP_MPMQ_HAS_SERF, &mpm_supprts_serf);
if (rv != APR_SUCCESS) {
mpm_supprts_serf = 0;
}
return OK;
}
static void register_hooks(apr_pool_t *p)
{
ap_register_provider(p, AP_SERF_CLUSTER_PROVIDER,
"heartbeat", "0", &builtin_heartbeat);
ap_register_provider(p, AP_SERF_CLUSTER_PROVIDER,
"static", "0", &builtin_static);
ap_hook_post_config(serf_post_config, NULL, NULL, APR_HOOK_MIDDLE);
ap_hook_handler(serf_handler, NULL, NULL, APR_HOOK_FIRST);
}
AP_DECLARE_MODULE(serf) =
{
STANDARD20_MODULE_STUFF,
create_dir_config,
NULL,
create_server_config,
merge_server_config,
serf_cmds,
register_hooks
};