Google Cloud client libraries use HTTPS and gRPC in underlying communication
with the services. In both protocols, you can configure a proxy using https.proxyHost
and, optionally, https.proxyPort
properties.
Configure a proxy with HTTP
For HTTP clients, you can configure a basic proxy by using http.proxyHost
and
related system properties, as documented by Java Networking and Proxies
.
For a custom proxy (for example, an authenticated proxy), provide a
custom HttpTransportFactory
to GoogleCredentials
:
import
com.google.api.client.http. HttpTransport
;
import
com.google.api.client.http.apache.v2. ApacheHttpTransport
;
import
com.google.auth.http. HttpTransportFactory
;
import
com.google.auth.oauth2. GoogleCredentials
;
import
org.apache.http.HttpHost
;
import
org.apache.http.auth.AuthScope
;
import
org.apache.http.auth.UsernamePasswordCredentials
;
import
org.apache.http.client.CredentialsProvider
;
import
org.apache.http.client.HttpClient
;
import
org.apache.http.conn.routing.HttpRoutePlanner
;
import
org.apache.http.impl.client.BasicCredentialsProvider
;
import
org.apache.http.impl.client.ProxyAuthenticationStrategy
;
import
org.apache.http.impl.conn.DefaultProxyRoutePlanner
;
import
java.io.IOException
;
public
class
ProxyExample
{
public
GoogleCredentials
getCredentials
()
throws
IOException
{
HttpTransportFactory
httpTransportFactory
=
getHttpTransportFactory
(
"some-host"
,
8080
,
"some-username"
,
"some-password"
);
return
GoogleCredentials
.
getApplicationDefault
(
httpTransportFactory
);
}
public
HttpTransportFactory
getHttpTransportFactory
(
String
proxyHost
,
int
proxyPort
,
String
proxyUsername
,
String
proxyPassword
)
{
HttpHost
proxyHostDetails
=
new
HttpHost
(
proxyHost
,
proxyPort
);
HttpRoutePlanner
httpRoutePlanner
=
new
DefaultProxyRoutePlanner
(
proxyHostDetails
);
CredentialsProvider
credentialsProvider
=
new
BasicCredentialsProvider
();
credentialsProvider
.
setCredentials
(
new
AuthScope
(
proxyHostDetails
.
getHostName
(),
proxyHostDetails
.
getPort
()),
new
UsernamePasswordCredentials
(
proxyUsername
,
proxyPassword
)
);
HttpClient
httpClient
=
ApacheHttpTransport
.
newDefaultHttpClientBuilder
()
.
setRoutePlanner
(
httpRoutePlanner
)
.
setProxyAuthenticationStrategy
(
ProxyAuthenticationStrategy
.
INSTANCE
)
.
setDefaultCredentialsProvider
(
credentialsProvider
)
.
build
();
final
HttpTransport
httpTransport
=
new
ApacheHttpTransport
(
httpClient
);
return
new
HttpTransportFactory
()
{
@Override
public
HttpTransport
create
()
{
return
httpTransport
;
}
};
}
}
The preceding example requires com.google.http-client:google-http-client-apache-v2
.
Configure a proxy with a gRPC custom proxy configuration
For a custom proxy with gRPC, supply a ProxyDetector
to
the ManagedChannelBuilder
:
Replace PROXY_USERNAME
, PROXY_PASSWORD
, PROXY_HOST
, and PROXY_PORT
with the credentials and address of your proxy.
import
com.google.api.core. ApiFunction
;
import
com.google.api.gax.rpc. TransportChannelProvider
;
import
com.google.cloud.tasks.v2. CloudTasksClient
;
import
com.google.cloud.tasks.v2. CloudTasksSettings
;
import
com.google.cloud.tasks.v2.stub.CloudTasksStubSettings
;
import
io.grpc.HttpConnectProxiedSocketAddress
;
import
io.grpc.ManagedChannelBuilder
;
import
io.grpc.ProxiedSocketAddress
;
import
io.grpc.ProxyDetector
;
import
javax.annotation.Nullable
;
import
java.io.IOException
;
import
java.net.InetSocketAddress
;
import
java.net.SocketAddress
;
public
CloudTasksClient
getService
()
throws
IOException
{
TransportChannelProvider
transportChannelProvider
=
CloudTasksStubSettings
.
defaultGrpcTransportProviderBuilder
()
.
setChannelConfigurator
(
new
ApiFunction<ManagedChannelBuilder
,
ManagedChannelBuilder
> ()
{
@Override
public
ManagedChannelBuilder
apply
(
ManagedChannelBuilder
managedChannelBuilder
)
{
return
managedChannelBuilder
.
proxyDetector
(
new
ProxyDetector
()
{
@Nullable
@Override
public
ProxiedSocketAddress
proxyFor
(
SocketAddress
socketAddress
)
throws
IOException
{
return
HttpConnectProxiedSocketAddress
.
newBuilder
()
.
setUsername
(
PROXY_USERNAME
)
.
setPassword
(
PROXY_PASSWORD
)
.
setProxyAddress
(
new
InetSocketAddress
(
PROXY_HOST
,
PROXY_PORT
))
.
setTargetAddress
((
InetSocketAddress
)
socketAddress
)
.
build
();
}
});
}
})
.
build
();
CloudTasksSettings
cloudTasksSettings
=
CloudTasksSettings
.
newBuilder
()
.
setTransportChannelProvider
(
transportChannelProvider
)
.
build
();
return
CloudTasksClient
.
create
(
cloudTasksSettings
);
}
