Future<bool> ZooKeeperSlavesManagerStorage::updated(const string& path)
{
int ret;
string result;
if (path == znode) {
LOG(INFO) << "Slaves manager storage found updates in ZooKeeper "
<< "... propogating changes";
ret = zk->get(znode, true, &result, NULL);
if (ret != ZOK) {
LOG(WARNING) << "Slaves manager storage failed to get '" << znode
<< "' in ZooKeeper! (" << zk->message(ret) << ")";
return false;
}
// Parse what's in ZooKeeper into active/inactive hostname port pairs.
multihashmap<string, uint16_t> active;
if (parse("active=", result, &active)) {
process::dispatch(slavesManager, &SlavesManager::updateActive, active);
}
multihashmap<string, uint16_t> inactive;
if (parse("inactive=", result, &inactive)) {
process::dispatch(slavesManager, &SlavesManager::updateInactive, inactive);
}
} else {
LOG(WARNING) << "Slaves manager stoage not expecting changes to path '"
<< path << "' in ZooKeeper";
return false;
}
return true;
}
Future<bool> ZooKeeperSlavesManagerStorage::add(const string& hostname, uint16_t port)
{
// TODO(benh): Use ZooKeeperSlavesManagerStorage::parse to clean up code.
int ret;
string result;
Stat stat;
ret = zk->get(znode, true, &result, &stat);
if (ret != ZOK) {
LOG(WARNING) << "Slaves manager storage failed to get '" << znode
<< "' in ZooKeeper! (" << zk->message(ret) << ")";
return false;
}
ostringstream out;
out << hostname << ":" << port;
if (result.size() == 0) {
out << "active=" << hostname << ":" << port << "\n";
out << "inactive=\n";
result = out.str();
} else {
const string active("active=");
size_t index = result.find(active);
if (index == string::npos) {
LOG(WARNING) << "Slaves manager storage found bad data in '" << znode
<< "', could not find 'active='";
return false;
}
if (result[index + active.size()] != '\n') {
out << ",";
}
result.insert(index + active.size(), out.str());
}
// Set the data in the znode.
ret = zk->set(znode, result, stat.version);
if (ret != ZOK) {
LOG(WARNING) << "Slaves manager storage could not add slave "
<< hostname << ":" << port
<< " to '" << znode << "' in ZooKeeper! ("
<< zk->message(ret) << ")";
return false;
}
return true;
}
Future<bool> ZooKeeperSlavesManagerStorage::remove(const string& hostname, uint16_t port)
{
// TODO(benh): Use ZooKeeperSlavesManagerStorage::parse to clean up code.
int ret;
string result;
Stat stat;
ret = zk->get(znode, true, &result, &stat);
if (ret != ZOK) {
LOG(WARNING) << "Slaves manager storage failed to get '" << znode
<< "' in ZooKeeper! (" << zk->message(ret) << ")";
return false;
}
ostringstream out;
out << hostname << ":" << port;
size_t index = result.find(out.str());
if (index == string::npos) {
LOG(WARNING) << "Slaves manager storage could not remove slave "
<< hostname << ":" << port
<< " because not currently active or inactive";
return false;
} else if (index == 0) {
LOG(WARNING) << "Bad data in '" << znode;
return false;
}
if (result[index - 1] == '=') {
if (result[index + out.str().size()] == '\n') {
result.erase(index, out.str().size());
} else {
result.erase(index, out.str().size() + 1);
}
} else {
result.erase(index - 1, out.str().size() + 1);
}
// Set the data in the znode.
ret = zk->set(znode, result, stat.version);
if (ret != ZOK) {
LOG(WARNING) << "Slaves manager storage could not remove slave "
<< hostname << ":" << port
<< " from '" << znode << "' in ZooKeeper! ("
<< zk->message(ret) << ")";
return false;
}
return true;
}
void LogProcess::regroup()
{
vector<string> results;
int ret = zk->getChildren(znode + "/replicas", false, &results);
if (ret != ZOK) {
LOG(FATAL) << "Failed to get children of '" << znode << "/replicas"
<< "' in ZooKeeper: " << zk->message(ret);
}
set<UPID> current;
set<UPID> added;
set<UPID> removed;
foreach (const string& result, results) {
string s;
int ret = zk->get(znode + "/replicas/" + result, false, &s, NULL);
UPID pid = s;
current.insert(pid);
}