1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
#include <Common/RemoteProxyConfigurationResolver.h>
#include <utility>
#include <IO/HTTPCommon.h>
#include <Poco/StreamCopier.h>
#include <Poco/Net/HTTPRequest.h>
#include <Poco/Net/HTTPResponse.h>
#include <Common/logger_useful.h>
#include <Common/DNSResolver.h>
namespace DB
{
namespace ErrorCodes
{
extern const int BAD_ARGUMENTS;
}
RemoteProxyConfigurationResolver::RemoteProxyConfigurationResolver(
const Poco::URI & endpoint_,
String proxy_protocol_,
unsigned proxy_port_,
unsigned cache_ttl_
)
: endpoint(endpoint_), proxy_protocol(std::move(proxy_protocol_)), proxy_port(proxy_port_), cache_ttl(cache_ttl_)
{
}
ProxyConfiguration RemoteProxyConfigurationResolver::resolve()
{
auto * logger = &Poco::Logger::get("RemoteProxyConfigurationResolver");
LOG_DEBUG(logger, "Obtain proxy using resolver: {}", endpoint.toString());
std::lock_guard lock(cache_mutex);
std::chrono::time_point<std::chrono::system_clock> now = std::chrono::system_clock::now();
if (cache_ttl.count() && cache_valid && now <= cache_timestamp + cache_ttl && now >= cache_timestamp)
{
LOG_DEBUG(logger,
"Use cached proxy: {}://{}:{}",
cached_config.protocol,
cached_config.host,
cached_config.port
);
return cached_config;
}
/// 1 second is enough for now.
/// TODO: Make timeouts configurable.
ConnectionTimeouts timeouts(
Poco::Timespan(1000000), /// Connection timeout.
Poco::Timespan(1000000), /// Send timeout.
Poco::Timespan(1000000) /// Receive timeout.
);
try
{
/// It should be just empty GET request.
Poco::Net::HTTPRequest request(Poco::Net::HTTPRequest::HTTP_GET, endpoint.getPath(), Poco::Net::HTTPRequest::HTTP_1_1);
const auto & host = endpoint.getHost();
auto resolved_hosts = DNSResolver::instance().resolveHostAll(host);
HTTPSessionPtr session;
for (size_t i = 0; i < resolved_hosts.size(); ++i)
{
auto resolved_endpoint = endpoint;
resolved_endpoint.setHost(resolved_hosts[i].toString());
session = makeHTTPSession(resolved_endpoint, timeouts);
try
{
session->sendRequest(request);
break;
}
catch (...)
{
if (i + 1 == resolved_hosts.size())
throw;
}
}
Poco::Net::HTTPResponse response;
auto & response_body_stream = session->receiveResponse(response);
if (response.getStatus() != Poco::Net::HTTPResponse::HTTP_OK)
throw Exception(ErrorCodes::BAD_ARGUMENTS, "Proxy resolver returned not OK status: {}", response.getReason());
String proxy_host;
/// Read proxy host as string from response body.
Poco::StreamCopier::copyToString(response_body_stream, proxy_host);
LOG_DEBUG(logger, "Use proxy: {}://{}:{}", proxy_protocol, proxy_host, proxy_port);
cached_config.protocol = ProxyConfiguration::protocolFromString(proxy_protocol);
cached_config.host = proxy_host;
cached_config.port = proxy_port;
cache_timestamp = std::chrono::system_clock::now();
cache_valid = true;
return cached_config;
}
catch (...)
{
tryLogCurrentException("RemoteProxyConfigurationResolver", "Failed to obtain proxy");
return {};
}
}
void RemoteProxyConfigurationResolver::errorReport(const ProxyConfiguration & config)
{
if (config.host.empty())
return;
std::lock_guard lock(cache_mutex);
if (!cache_ttl.count() || !cache_valid)
return;
if (std::tie(cached_config.protocol, cached_config.host, cached_config.port)
!= std::tie(config.protocol, config.host, config.port))
return;
/// Invalidate cached proxy when got error with this proxy
cache_valid = false;
}
}
|
