ClickHouse/src/Interpreters/Cluster.cpp

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#include <Interpreters/Cluster.h>
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#include <common/SimpleCache.h>
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#include <Common/DNSResolver.h>
#include <Common/escapeForFileName.h>
#include <Common/isLocalAddress.h>
#include <Common/StringUtils/StringUtils.h>
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#include <Common/parseAddress.h>
#include <Common/Config/AbstractConfigurationComparison.h>
#include <Core/Settings.h>
#include <IO/WriteHelpers.h>
#include <IO/ReadHelpers.h>
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#include <Poco/Util/AbstractConfiguration.h>
#include <Poco/Util/Application.h>
#include <ext/range.h>
#include <boost/range/algorithm_ext/erase.hpp>
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namespace DB
{
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namespace ErrorCodes
{
extern const int UNKNOWN_ELEMENT_IN_CONFIG;
extern const int EXCESSIVE_ELEMENT_IN_CONFIG;
extern const int LOGICAL_ERROR;
extern const int SHARD_HAS_NO_CONNECTIONS;
extern const int SYNTAX_ERROR;
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}
namespace
{
/// Default shard weight.
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constexpr UInt32 default_weight = 1;
inline bool isLocalImpl(const Cluster::Address & address, const Poco::Net::SocketAddress & resolved_address, UInt16 clickhouse_port)
{
/// If there is replica, for which:
/// - its port is the same that the server is listening;
/// - its host is resolved to set of addresses, one of which is the same as one of addresses of network interfaces of the server machine*;
/// then we must go to this shard without any inter-process communication.
///
/// * - this criteria is somewhat approximate.
///
/// Also, replica is considered non-local, if it has default database set
/// (only reason is to avoid query rewrite).
return address.default_database.empty() && isLocalAddress(resolved_address, clickhouse_port);
}
void concatInsertPath(std::string & insert_path, const std::string & dir_name)
{
if (insert_path.empty())
insert_path = dir_name;
else
insert_path += "," + dir_name;
}
}
/// Implementation of Cluster::Address class
std::optional<Poco::Net::SocketAddress> Cluster::Address::getResolvedAddress() const
{
try
{
return DNSResolver::instance().resolveAddress(host_name, port);
}
catch (...)
{
/// Failure in DNS resolution in cluster initialization is Ok.
tryLogCurrentException("Cluster");
return {};
}
}
bool Cluster::Address::isLocal(UInt16 clickhouse_port) const
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{
if (auto resolved = getResolvedAddress())
return isLocalImpl(*this, *resolved, clickhouse_port);
return false;
}
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Cluster::Address::Address(
const Poco::Util::AbstractConfiguration & config,
const String & config_prefix,
const String & cluster_,
const String & cluster_secret_,
UInt32 shard_index_,
UInt32 replica_index_)
: cluster(cluster_)
, cluster_secret(cluster_secret_)
, shard_index(shard_index_)
, replica_index(replica_index_)
{
host_name = config.getString(config_prefix + ".host");
port = static_cast<UInt16>(config.getInt(config_prefix + ".port"));
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if (config.has(config_prefix + ".user"))
user_specified = true;
user = config.getString(config_prefix + ".user", "default");
password = config.getString(config_prefix + ".password", "");
default_database = config.getString(config_prefix + ".default_database", "");
secure = config.getBool(config_prefix + ".secure", false) ? Protocol::Secure::Enable : Protocol::Secure::Disable;
priority = config.getInt(config_prefix + ".priority", 1);
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const char * port_type = secure == Protocol::Secure::Enable ? "tcp_port_secure" : "tcp_port";
is_local = isLocal(config.getInt(port_type, 0));
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/// By default compression is disabled if address looks like localhost.
/// NOTE: it's still enabled when interacting with servers on different port, but we don't want to complicate the logic.
compression = config.getBool(config_prefix + ".compression", !is_local)
? Protocol::Compression::Enable : Protocol::Compression::Disable;
}
Cluster::Address::Address(
const String & host_port_,
const String & user_,
const String & password_,
UInt16 clickhouse_port,
bool secure_,
Int64 priority_,
UInt32 shard_index_,
UInt32 replica_index_)
: user(user_)
, password(password_)
{
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auto parsed_host_port = parseAddress(host_port_, clickhouse_port);
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host_name = parsed_host_port.first;
port = parsed_host_port.second;
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secure = secure_ ? Protocol::Secure::Enable : Protocol::Secure::Disable;
priority = priority_;
is_local = isLocal(clickhouse_port);
shard_index = shard_index_;
replica_index = replica_index_;
}
String Cluster::Address::toString() const
{
return toString(host_name, port);
}
String Cluster::Address::toString(const String & host_name, UInt16 port)
{
return escapeForFileName(host_name) + ':' + DB::toString(port);
}
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String Cluster::Address::readableString() const
{
String res;
/// If it looks like IPv6 address add braces to avoid ambiguity in ipv6_host:port notation
if (host_name.find_first_of(':') != std::string::npos && !host_name.empty() && host_name.back() != ']')
res += '[' + host_name + ']';
else
res += host_name;
res += ':' + DB::toString(port);
return res;
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}
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std::pair<String, UInt16> Cluster::Address::fromString(const String & host_port_string)
{
auto pos = host_port_string.find_last_of(':');
if (pos == std::string::npos)
throw Exception("Incorrect <host>:<port> format " + host_port_string, ErrorCodes::SYNTAX_ERROR);
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return {unescapeForFileName(host_port_string.substr(0, pos)), parse<UInt16>(host_port_string.substr(pos + 1))};
}
String Cluster::Address::toFullString(bool use_compact_format) const
{
if (use_compact_format)
{
if (shard_index == 0 || replica_index == 0)
// shard_num/replica_num like in system.clusters table
throw Exception("shard_num/replica_num cannot be zero", ErrorCodes::LOGICAL_ERROR);
return "shard" + std::to_string(shard_index) + "_replica" + std::to_string(replica_index);
}
else
{
return
escapeForFileName(user)
+ (password.empty() ? "" : (':' + escapeForFileName(password))) + '@'
+ escapeForFileName(host_name) + ':' + std::to_string(port)
+ (default_database.empty() ? "" : ('#' + escapeForFileName(default_database)))
+ ((secure == Protocol::Secure::Enable) ? "+secure" : "");
}
}
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Cluster::Address Cluster::Address::fromFullString(const String & full_string)
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{
const char * address_begin = full_string.data();
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const char * address_end = address_begin + full_string.size();
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const char * user_pw_end = strchr(full_string.data(), '@');
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/// parsing with the new [shard{shard_index}[_replica{replica_index}]] format
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if (!user_pw_end && startsWith(full_string, "shard"))
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{
const char * underscore = strchr(full_string.data(), '_');
Address address;
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address.shard_index = parse<UInt32>(address_begin + strlen("shard"));
address.replica_index = underscore ? parse<UInt32>(underscore + strlen("_replica")) : 0;
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return address;
}
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else
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{
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/// parsing with the old user[:password]@host:port#default_database format
/// This format is appeared to be inconvenient for the following reasons:
/// - credentials are exposed in file name;
/// - the file name can be too long.
Protocol::Secure secure = Protocol::Secure::Disable;
const char * secure_tag = "+secure";
if (endsWith(full_string, secure_tag))
{
address_end -= strlen(secure_tag);
secure = Protocol::Secure::Enable;
}
const char * colon = strchr(full_string.data(), ':');
if (!user_pw_end || !colon)
throw Exception("Incorrect user[:password]@host:port#default_database format " + full_string, ErrorCodes::SYNTAX_ERROR);
const bool has_pw = colon < user_pw_end;
const char * host_end = has_pw ? strchr(user_pw_end + 1, ':') : colon;
if (!host_end)
throw Exception("Incorrect address '" + full_string + "', it does not contain port", ErrorCodes::SYNTAX_ERROR);
const char * has_db = strchr(full_string.data(), '#');
const char * port_end = has_db ? has_db : address_end;
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Address address;
address.secure = secure;
address.port = parse<UInt16>(host_end + 1, port_end - (host_end + 1));
address.host_name = unescapeForFileName(std::string(user_pw_end + 1, host_end));
address.user = unescapeForFileName(std::string(address_begin, has_pw ? colon : user_pw_end));
address.password = has_pw ? unescapeForFileName(std::string(colon + 1, user_pw_end)) : std::string();
address.default_database = has_db ? unescapeForFileName(std::string(has_db + 1, address_end)) : std::string();
// address.priority ignored
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return address;
}
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}
/// Implementation of Clusters class
Clusters::Clusters(const Poco::Util::AbstractConfiguration & config, const Settings & settings, const String & config_prefix)
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{
updateClusters(config, settings, config_prefix);
}
ClusterPtr Clusters::getCluster(const std::string & cluster_name) const
{
std::lock_guard lock(mutex);
auto it = impl.find(cluster_name);
return (it != impl.end()) ? it->second : nullptr;
}
void Clusters::setCluster(const String & cluster_name, const std::shared_ptr<Cluster> & cluster)
{
std::lock_guard lock(mutex);
impl[cluster_name] = cluster;
}
void Clusters::updateClusters(const Poco::Util::AbstractConfiguration & new_config, const Settings & settings, const String & config_prefix, Poco::Util::AbstractConfiguration * old_config)
{
Poco::Util::AbstractConfiguration::Keys new_config_keys;
new_config.keys(config_prefix, new_config_keys);
/// If old config is set, we will update only clusters with updated config.
/// In this case, we first need to find clusters that were deleted from config.
Poco::Util::AbstractConfiguration::Keys deleted_keys;
if (old_config)
{
std::sort(new_config_keys.begin(), new_config_keys.end());
Poco::Util::AbstractConfiguration::Keys old_config_keys;
old_config->keys(config_prefix, old_config_keys);
std::sort(old_config_keys.begin(), old_config_keys.end());
std::set_difference(
old_config_keys.begin(), old_config_keys.end(), new_config_keys.begin(), new_config_keys.end(), std::back_inserter(deleted_keys));
}
std::lock_guard lock(mutex);
/// If old config is set, remove deleted clusters from impl, otherwise just clear it.
if (old_config)
{
for (const auto & key : deleted_keys)
impl.erase(key);
}
else
impl.clear();
for (const auto & key : new_config_keys)
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{
if (key.find('.') != String::npos)
throw Exception("Cluster names with dots are not supported: '" + key + "'", ErrorCodes::SYNTAX_ERROR);
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/// If old config is set and cluster config wasn't changed, don't update this cluster.
if (!old_config || !isSameConfiguration(new_config, *old_config, config_prefix + "." + key))
impl[key] = std::make_shared<Cluster>(new_config, settings, config_prefix, key);
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}
}
Clusters::Impl Clusters::getContainer() const
{
std::lock_guard lock(mutex);
/// The following line copies container of shared_ptrs to return value under lock
return impl;
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}
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/// Implementation of `Cluster` class
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Cluster::Cluster(const Poco::Util::AbstractConfiguration & config,
const Settings & settings,
const String & config_prefix_,
const String & cluster_name)
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{
auto config_prefix = config_prefix_ + "." + cluster_name;
Poco::Util::AbstractConfiguration::Keys config_keys;
config.keys(config_prefix, config_keys);
config_prefix += ".";
secret = config.getString(config_prefix + "secret", "");
boost::range::remove_erase(config_keys, "secret");
if (config_keys.empty())
throw Exception("No cluster elements (shard, node) specified in config at path " + config_prefix, ErrorCodes::SHARD_HAS_NO_CONNECTIONS);
UInt32 current_shard_num = 1;
for (const auto & key : config_keys)
{
if (startsWith(key, "node"))
{
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/// Shard without replicas.
Addresses addresses;
const auto & prefix = config_prefix + key;
const auto weight = config.getInt(prefix + ".weight", default_weight);
addresses.emplace_back(config, prefix, cluster_name, secret, current_shard_num, 1);
const auto & address = addresses.back();
ShardInfo info;
info.shard_num = current_shard_num;
info.weight = weight;
if (address.is_local)
info.local_addresses.push_back(address);
ConnectionPoolPtr pool = std::make_shared<ConnectionPool>(
settings.distributed_connections_pool_size,
address.host_name, address.port,
address.default_database, address.user, address.password,
address.cluster, address.cluster_secret,
"server", address.compression,
address.secure, address.priority);
info.pool = std::make_shared<ConnectionPoolWithFailover>(
ConnectionPoolPtrs{pool}, settings.load_balancing);
info.per_replica_pools = {std::move(pool)};
if (weight)
slot_to_shard.insert(std::end(slot_to_shard), weight, shards_info.size());
shards_info.emplace_back(std::move(info));
addresses_with_failover.emplace_back(std::move(addresses));
}
else if (startsWith(key, "shard"))
{
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/// Shard with replicas.
Poco::Util::AbstractConfiguration::Keys replica_keys;
config.keys(config_prefix + key, replica_keys);
addresses_with_failover.emplace_back();
Addresses & replica_addresses = addresses_with_failover.back();
UInt32 current_replica_num = 1;
const auto & partial_prefix = config_prefix + key + ".";
const auto weight = config.getUInt(partial_prefix + ".weight", default_weight);
bool internal_replication = config.getBool(partial_prefix + ".internal_replication", false);
ShardInfoInsertPathForInternalReplication insert_paths;
for (const auto & replica_key : replica_keys)
{
if (startsWith(replica_key, "weight") || startsWith(replica_key, "internal_replication"))
continue;
if (startsWith(replica_key, "replica"))
{
replica_addresses.emplace_back(config,
partial_prefix + replica_key,
cluster_name,
secret,
current_shard_num,
current_replica_num);
++current_replica_num;
if (internal_replication)
{
/// use_compact_format=0
{
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auto dir_name = replica_addresses.back().toFullString(false /* use_compact_format */);
if (!replica_addresses.back().is_local)
concatInsertPath(insert_paths.prefer_localhost_replica, dir_name);
concatInsertPath(insert_paths.no_prefer_localhost_replica, dir_name);
}
/// use_compact_format=1
{
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auto dir_name = replica_addresses.back().toFullString(true /* use_compact_format */);
if (!replica_addresses.back().is_local)
concatInsertPath(insert_paths.prefer_localhost_replica_compact, dir_name);
concatInsertPath(insert_paths.no_prefer_localhost_replica_compact, dir_name);
}
}
}
else
throw Exception("Unknown element in config: " + replica_key, ErrorCodes::UNKNOWN_ELEMENT_IN_CONFIG);
}
Addresses shard_local_addresses;
ConnectionPoolPtrs all_replicas_pools;
all_replicas_pools.reserve(replica_addresses.size());
for (const auto & replica : replica_addresses)
{
auto replica_pool = std::make_shared<ConnectionPool>(
settings.distributed_connections_pool_size,
replica.host_name, replica.port,
replica.default_database, replica.user, replica.password,
replica.cluster, replica.cluster_secret,
"server", replica.compression,
replica.secure, replica.priority);
all_replicas_pools.emplace_back(replica_pool);
if (replica.is_local)
shard_local_addresses.push_back(replica);
}
ConnectionPoolWithFailoverPtr shard_pool = std::make_shared<ConnectionPoolWithFailover>(
all_replicas_pools, settings.load_balancing,
settings.distributed_replica_error_half_life.totalSeconds(), settings.distributed_replica_error_cap);
if (weight)
slot_to_shard.insert(std::end(slot_to_shard), weight, shards_info.size());
shards_info.push_back({
std::move(insert_paths),
current_shard_num,
weight,
std::move(shard_local_addresses),
std::move(shard_pool),
std::move(all_replicas_pools),
internal_replication
});
}
else
throw Exception("Unknown element in config: " + key, ErrorCodes::UNKNOWN_ELEMENT_IN_CONFIG);
++current_shard_num;
}
if (addresses_with_failover.empty())
throw Exception("There must be either 'node' or 'shard' elements in config", ErrorCodes::EXCESSIVE_ELEMENT_IN_CONFIG);
initMisc();
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}
Cluster::Cluster(const Settings & settings, const std::vector<std::vector<String>> & names,
const String & username, const String & password, UInt16 clickhouse_port, bool treat_local_as_remote,
bool secure, Int64 priority)
{
UInt32 current_shard_num = 1;
for (const auto & shard : names)
{
Addresses current;
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for (const auto & replica : shard)
current.emplace_back(replica, username, password, clickhouse_port, secure, priority, current_shard_num, current.size() + 1);
addresses_with_failover.emplace_back(current);
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Addresses shard_local_addresses;
ConnectionPoolPtrs all_replicas;
all_replicas.reserve(current.size());
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for (const auto & replica : current)
{
auto replica_pool = std::make_shared<ConnectionPool>(
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settings.distributed_connections_pool_size,
replica.host_name, replica.port,
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replica.default_database, replica.user, replica.password,
replica.cluster, replica.cluster_secret,
"server", replica.compression, replica.secure, replica.priority);
all_replicas.emplace_back(replica_pool);
if (replica.is_local && !treat_local_as_remote)
shard_local_addresses.push_back(replica);
}
ConnectionPoolWithFailoverPtr shard_pool = std::make_shared<ConnectionPoolWithFailover>(
all_replicas, settings.load_balancing,
settings.distributed_replica_error_half_life.totalSeconds(), settings.distributed_replica_error_cap);
slot_to_shard.insert(std::end(slot_to_shard), default_weight, shards_info.size());
shards_info.push_back({
{}, // insert_path_for_internal_replication
current_shard_num,
default_weight,
std::move(shard_local_addresses),
std::move(shard_pool),
std::move(all_replicas),
false // has_internal_replication
});
++current_shard_num;
}
initMisc();
}
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Poco::Timespan Cluster::saturate(Poco::Timespan v, Poco::Timespan limit)
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{
if (limit.totalMicroseconds() == 0)
return v;
else
return (v > limit) ? limit : v;
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}
void Cluster::initMisc()
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{
for (const auto & shard_info : shards_info)
{
if (!shard_info.isLocal() && !shard_info.hasRemoteConnections())
throw Exception("Found shard without any specified connection",
ErrorCodes::SHARD_HAS_NO_CONNECTIONS);
}
for (const auto & shard_info : shards_info)
{
if (shard_info.isLocal())
++local_shard_count;
else
++remote_shard_count;
}
for (auto & shard_info : shards_info)
{
if (!shard_info.isLocal())
{
any_remote_shard_info = &shard_info;
break;
}
}
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}
std::unique_ptr<Cluster> Cluster::getClusterWithReplicasAsShards(const Settings & settings) const
{
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return std::unique_ptr<Cluster>{ new Cluster(ReplicasAsShardsTag{}, *this, settings)};
}
std::unique_ptr<Cluster> Cluster::getClusterWithSingleShard(size_t index) const
{
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return std::unique_ptr<Cluster>{ new Cluster(SubclusterTag{}, *this, {index}) };
}
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std::unique_ptr<Cluster> Cluster::getClusterWithMultipleShards(const std::vector<size_t> & indices) const
{
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return std::unique_ptr<Cluster>{ new Cluster(SubclusterTag{}, *this, indices) };
}
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Cluster::Cluster(Cluster::ReplicasAsShardsTag, const Cluster & from, const Settings & settings)
{
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if (from.addresses_with_failover.empty())
throw Exception("Cluster is empty", ErrorCodes::LOGICAL_ERROR);
UInt32 shard_num = 0;
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std::set<std::pair<String, int>> unique_hosts;
for (size_t shard_index : ext::range(0, from.shards_info.size()))
{
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const auto & replicas = from.addresses_with_failover[shard_index];
for (const auto & address : replicas)
{
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if (!unique_hosts.emplace(address.host_name, address.port).second)
continue; /// Duplicate host, skip.
ShardInfo info;
info.shard_num = ++shard_num;
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if (address.is_local)
info.local_addresses.push_back(address);
ConnectionPoolPtr pool = std::make_shared<ConnectionPool>(
settings.distributed_connections_pool_size,
address.host_name,
address.port,
address.default_database,
address.user,
address.password,
address.cluster,
address.cluster_secret,
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"server",
address.compression,
address.secure,
address.priority);
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info.pool = std::make_shared<ConnectionPoolWithFailover>(ConnectionPoolPtrs{pool}, settings.load_balancing);
info.per_replica_pools = {std::move(pool)};
addresses_with_failover.emplace_back(Addresses{address});
shards_info.emplace_back(std::move(info));
}
}
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initMisc();
}
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Cluster::Cluster(Cluster::SubclusterTag, const Cluster & from, const std::vector<size_t> & indices)
{
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for (size_t index : indices)
{
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shards_info.emplace_back(from.shards_info.at(index));
if (!from.addresses_with_failover.empty())
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addresses_with_failover.emplace_back(from.addresses_with_failover.at(index));
}
initMisc();
}
const std::string & Cluster::ShardInfo::insertPathForInternalReplication(bool prefer_localhost_replica, bool use_compact_format) const
{
if (!has_internal_replication)
throw Exception("internal_replication is not set", ErrorCodes::LOGICAL_ERROR);
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const auto & paths = insert_path_for_internal_replication;
if (!use_compact_format)
{
if (prefer_localhost_replica)
return paths.prefer_localhost_replica;
else
return paths.no_prefer_localhost_replica;
}
else
{
if (prefer_localhost_replica)
return paths.prefer_localhost_replica_compact;
else
return paths.no_prefer_localhost_replica_compact;
}
}
bool Cluster::maybeCrossReplication() const
{
/// Cluster can be used for cross-replication if some replicas have different default database names,
/// so one clickhouse-server instance can contain multiple replicas.
if (addresses_with_failover.empty())
return false;
const String & database_name = addresses_with_failover.front().front().default_database;
for (const auto & shard : addresses_with_failover)
for (const auto & replica : shard)
if (replica.default_database != database_name)
return true;
return false;
}
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}