[
https://issues.apache.org/jira/browse/TS-4723?focusedWorklogId=26279&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-26279
]
ASF GitHub Bot logged work on TS-4723:
--------------------------------------
Author: ASF GitHub Bot
Created on: 10/Aug/16 15:02
Start Date: 10/Aug/16 15:02
Worklog Time Spent: 10m
Work Description: Github user SolidWallOfCode commented on a diff in the
pull request:
https://github.com/apache/trafficserver/pull/843#discussion_r74262139
--- Diff: plugins/experimental/carp/CarpConfigPool.cc ---
@@ -0,0 +1,218 @@
+/** @file
+
+ Manage a list of CARP configurations
+
+ @section license License
+
+ 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 <sstream>
+
+#include "Common.h"
+#include "CarpConfigPool.h"
+#include "UrlComponents.h"
+#include "CarpHost.h"
+
+#include <netdb.h>
+#include <ts/ts.h>
+
+using namespace std;
+
+/*******************************************************************/
+CarpConfigPool::CarpConfigPool()
+{
+ _globalHash = NULL;
+ _globalConfig = NULL;
+}
+
+/*******************************************************************/
+CarpConfigPool::~CarpConfigPool()
+{
+ for(CarpConfigListIter it=_configList.begin(); it != _configList.end();
it++) {
+ it->second->_config->stop();
+ delete it->second;
+ }
+}
+/*******************************************************************/
+static int initCarpConfigAndHash(CarpConfigAndHash * cch, string
sFilename) {
+ cch->_configPath = sFilename;
+ cch->_config = new CarpConfig();
+ TSAssert(cch->_config);
+
+ if (!cch->_config->loadConfig(sFilename)) {
+ return -1;
+ }
+
+ cch->_hashAlgo = new CarpHashAlgorithm(cch->_config);
+
+ TSAssert(cch->_hashAlgo);
+
+ CarpHostList* hostList = cch->_config->getHostList();
+ // add hosts, etc to hash algo
+ char szServerName[256];
+ *szServerName = 0;
+
+ if (!gethostname(szServerName, 255)) { // success!
+ TSDebug(DEBUG_TAG_INIT, "using %s as server name to detect 'self'",
+ szServerName);
+ }
+ char buf[1024];
+ struct hostent self, *selfhe = getHostIp(string(szServerName), &self,
buf,
+ sizeof(buf));
+
+ for (CarpHostListIter i = hostList->begin(); i != hostList->end(); i++) {
+ HashNode *hashNode;
+ bool bSelf = false;
+ if (NULL != selfhe) { // check for 'self'
+ // include hostname and port
+ bSelf = isSelf((*i)->getName(), (*i)->getPort(), selfhe);
+ }
+ if (cch->_config->getHealthCheckPort() == -1) { // did they
specify 'PORT'?
+ (*i)->setHealthCheckPort((*i)->getPort()); // set HC port from
server spec'd port
+ } else {
+ (*i)->setHealthCheckPort(cch->_config->getHealthCheckPort()); // set
HC port
+ }
+ string sHCUrl = cch->_config->getHealthCheckUrl();
+ size_t pos = sHCUrl.find("{port}");
+ if (pos != string::npos) { // need to replace '{port}' with servers
port
+ stringstream ss;
+ ss << (*i)->getPort();
+ sHCUrl.replace(pos, 6, ss.str()); // 6 = strlen of '{port}'
+ }
+ pos = sHCUrl.find("{host}");
+ if (pos != string::npos) {
+ sHCUrl.replace(pos, 6, (*i)->getName());
+ }
+ (*i)->setHealthCheckUrl(sHCUrl); // set HC Url
+
+ // Look up host and create addr struct for healthchecks
+ char hBuf[1024];
+ struct hostent host, *hosthe = getHostIp((*i)->getName(), &host, hBuf,
+ sizeof(hBuf));
+ if (hosthe) {
+ // convert hostent to sockaddr_in structure
+ sockaddr_in hIn;
+ memcpy(&hIn.sin_addr, hosthe->h_addr_list[0], hosthe->h_length);
+ hIn.sin_port = htons((*i)->getHealthCheckPort()); // set port
+ if (hosthe->h_length == 4) { // size match IPv4? assume such
+ hIn.sin_family = AF_INET;
+ } else { // assume IPv6
+ hIn.sin_family = AF_INET6;
+ }
+ (*i)->setHealthCheckAddr(
+ reinterpret_cast<struct sockaddr_storage &>(hIn));
+ hIn.sin_port = htons((*i)->getPort());
+ hashNode = new HashNode((*i)->getName(), (*i)->getPort(),
+ (*i)->getScheme(), (*i)->getWeight(), bSelf,
+ reinterpret_cast<struct sockaddr_storage &>(hIn),
+ (*i)->getGroup());
+ cch->_hashAlgo->addHost(hashNode);
+ } else {
+ //Config error or dns error. Should not continue
+ TSError("carp: error get peer address of host '%s'",
(*i)->getName().c_str());
+ return -1;
+ }
+
+ HttpFetch *f = new HttpFetch(sHCUrl, cch->_hashAlgo, hashNode);
+ cch->_config->addHealthCheckClient(f);
+ }
+ string diag;
+ cch->_config->dump(diag);
+ TSDebug(DEBUG_TAG_INIT, "Carp Configuration\n%s", diag.c_str());
+
+ // tell algo we are done configuring it
+ cch->_hashAlgo->algoInit();
+
+ return 1;
+}
+
+/*******************************************************************/
+int
+cleanHandler(TSCont cont, TSEvent event, void *edata) {
+ CarpConfigAndHash * cch = (CarpConfigAndHash *)TSContDataGet(cont);
+ delete cch;
+ TSContDestroy(cont);
+
+ return 1;
+}
+
+/*******************************************************************/
+CarpConfigAndHash*
+CarpConfigPool::processConfigFile(string sFilename,bool isGlobal)
+{
+
+ CarpConfigAndHash* cch = _configList[sFilename];
+
+ if ( NULL == cch ) { // new config file
+ cch = new CarpConfigAndHash();
+ _configList[sFilename] = cch;
+ TSDebug(DEBUG_TAG_INIT, "processing new config file '%s'",
sFilename.c_str());
+ if (initCarpConfigAndHash(cch, sFilename) < 0 ) {
+ return NULL;
+ }
+
+ if(isGlobal) { // extract global setting(s) from this config file and
save locally
+ _globalHash = cch->_hashAlgo;
+ _globalConfig = cch->_config;
+ }
+ // create and start health watcher thread
+ cch->_thread = TSThreadCreate(
CarpConfigHealthCheckThreadStart,static_cast<void *> (cch) );
+ } else { // config reload
+
+ TSDebug(DEBUG_TAG_HEALTH, "Reload the config file '%s'",
sFilename.c_str());
+ CarpConfigAndHash *newCCH = new CarpConfigAndHash();
+ CarpConfigAndHash *oldCCH = cch;
+ if (initCarpConfigAndHash(newCCH, sFilename) < 0 ) {
+ return NULL;
+ }
+ /*
+ * Find the status of current Host in previous HashAlgo, and
+ * then assign the value to the new HashAlgo.
+ */
+ size_t index;
+ vector<CarpHost*> *list = newCCH->_config->getHostList();
+ for (unsigned int i = 0; i < list->size(); i++) {
+ string name = (*list)[i]->getName();
--- End diff --
Any reason for this to not be `string const&`?
Issue Time Tracking
-------------------
Worklog Id: (was: 26279)
Time Spent: 2.5h (was: 2h 20m)
> ATS CARP Plugin
> ---------------
>
> Key: TS-4723
> URL: https://issues.apache.org/jira/browse/TS-4723
> Project: Traffic Server
> Issue Type: New Feature
> Components: Plugins
> Reporter: Eric Schwartz
> Assignee: Eric Schwartz
> Fix For: 7.0.0
>
> Time Spent: 2.5h
> Remaining Estimate: 0h
>
> Open sourcing this plugin we use internally within Yahoo in place of
> hierarchical caching.
> CARP is a plugin that allows you to group a bunch of ATS hosts into a cluster
> and share cache space across the entire group. This is done with consistent
> hashing on the object URL to generate an "owner" node in the cluster.
> Requests to any other node in the cluster will be forwarded on to the
> corresponding owner. More info in the README.
> Difference from internal version of note:
> I've ripped out some code we weren't entirely sure we could open source
> because of a hash function. If it turns out that we can open source this,
> I'll do so. The CarpHashAlgorithm class is meant to be extensible, so any
> consistent hash function can replace it. The function included here is pretty
> straightforward but not what we use in production, so just wanted to use that
> caveat.
> One last caveat:
> You'll see some code and documentation in here for object replication. This
> is something I added recently to CARP that allows you to specify an object be
> replicated a certain number of times in the cluster. This is useful if you
> have a network partition or if you're performing some sort of update. When an
> object's primary owner is unreachable, a node in the cluster can go to the
> secondary owner if it's available rather than having to fall all the way back
> to origin. While I've done some initial testing on this with my own cluster
> of hosts, it's not been tested in production so use at your own risk for now.
> I'll be sure to keep the open source community informed on the progress of
> our tests with this feature.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
