Package org.apache.hadoop.yarn.util

Class DockerClientConfigHandler

java.lang.Object

org.apache.hadoop.yarn.util.DockerClientConfigHandler

public final class DockerClientConfigHandler
extends Object

Commonly needed actions for handling the Docker client configurations. Credentials that are used to access private Docker registries are supplied. Actions include:

• Read the Docker client configuration json file from a FileSystem.
• Extract the authentication information from the configuration into Token and Credentials objects.
• Tokens are commonly shipped via the ContainerLaunchContext as a ByteBuffer, extract the Credentials.
• Write the Docker client configuration json back to the local filesystem to be used by the Docker command line.

Method Summary

Modifier and Type	Method	Description
static org.apache.hadoop.security.Credentials	getCredentialsFromTokensByteBuffer(ByteBuffer tokens)	Convert the Token ByteBuffer to the appropriate Credentials object.
static org.apache.hadoop.security.Credentials	readCredentialsFromConfigFile(org.apache.hadoop.fs.Path configFile, org.apache.hadoop.conf.Configuration conf, String applicationId)	Read the Docker client configuration and extract the auth tokens into Credentials.
static boolean	writeDockerCredentialsToPath(File outConfigFile, org.apache.hadoop.security.Credentials credentials)	Extract the Docker related tokens from the Credentials and write the Docker client configuration to the supplied File.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

readCredentialsFromConfigFile

public static org.apache.hadoop.security.Credentials readCredentialsFromConfigFile(org.apache.hadoop.fs.Path configFile,
 org.apache.hadoop.conf.Configuration conf,
 String applicationId)
                                                                            throws IOException

Read the Docker client configuration and extract the auth tokens into Credentials.

Parameters:

configFile - the Path to the Docker client configuration.

conf - the Configuration object, needed by the FileSystem.

applicationId - the application ID to associate the Credentials with.

Returns:

the populated Credential object with the Docker Tokens.

Throws:

IOException - if the file can not be read.

getCredentialsFromTokensByteBuffer

public static org.apache.hadoop.security.Credentials getCredentialsFromTokensByteBuffer(ByteBuffer tokens)
                                                                                 throws IOException

Convert the Token ByteBuffer to the appropriate Credentials object.

Parameters:

tokens - the Tokens from the ContainerLaunchContext.

Returns:

the Credentials object populated from the Tokens.

Throws:

IOException - io error occur.

writeDockerCredentialsToPath

public static boolean writeDockerCredentialsToPath(File outConfigFile,
 org.apache.hadoop.security.Credentials credentials)
                                            throws IOException

Extract the Docker related tokens from the Credentials and write the Docker client configuration to the supplied File.

Parameters:

outConfigFile - the File to write the Docker client configuration to.

credentials - the populated Credentials object.

Returns:

true if a Docker credential is found in the supplied credentials.

Throws:

IOException - if the write fails.