Package org.apache.catalina.tribes.membership.cloud

Class CloudMembershipProvider

java.lang.Object

org.apache.catalina.tribes.membership.MembershipProviderBase

org.apache.catalina.tribes.membership.cloud.CloudMembershipProvider

All Implemented Interfaces:

ChannelListener, Heartbeat, MembershipProvider

Direct Known Subclasses:

DNSMembershipProvider, KubernetesMembershipProvider

public abstract class CloudMembershipProvider
extends MembershipProviderBase
implements Heartbeat, ChannelListener

Abstract base class for cloud-based membership providers.

Field Summary

Fields

Modifier and Type	Field	Description
protected int	connectionTimeout	Connection timeout in milliseconds.
protected static java.lang.String	CUSTOM_ENV_PREFIX	Prefix for custom environment variables.
protected long	expirationTime	Member expiration time in milliseconds.
protected java.util.Map<java.lang.String,java.lang.String>	headers	HTTP headers for cloud API requests.
protected java.lang.String	localIp	The local IP address.
protected int	port	The local port number.
protected int	readTimeout	Read timeout in milliseconds.
protected static StringManager	sm	String manager for this class.
protected java.time.Instant	startTime	The time when this provider started.
protected StreamProvider	streamProvider	The provider for cloud API streams.
protected java.lang.String	url	The URL for the cloud membership service.

Fields inherited from class org.apache.catalina.tribes.membership.MembershipProviderBase

executor, membership, membershipListener, service

Constructor Summary

Constructors

Constructor	Description
CloudMembershipProvider()	Default constructor.

Method Summary

Modifier and Type	Method	Description
boolean	accept(java.io.Serializable msg, Member sender)	Invoked by the channel to determine if the listener will process this message or not.
protected static byte[]	digest(byte[] input)	Thread safe MD5 digest.
protected abstract Member[]	fetchMembers()	Fetch current cluster members from the cloud orchestration.
protected static java.lang.String	getEnv(java.lang.String... keys)	Get value of environment variable.
protected java.lang.String	getNamespace()	Get the Kubernetes namespace, or "tomcat" if the Kubernetes environment variable cannot be found (with a warning log about the missing namespace).
void	heartbeat()	Heartbeat invocation for resources cleanup etc
void	init(java.util.Properties properties)	Initialize the membership provider with the specified configuration.
void	messageReceived(java.io.Serializable msg, Member sender)	Receive a message from the channel
void	start(int level)	Start the membership provider.
boolean	stop(int level)	Stop the membership provider.
protected void	updateMember(Member member, boolean add)	Add or remove specified member.

Methods inherited from class org.apache.catalina.tribes.membership.MembershipProviderBase

getMember, getMembers, hasMembers, setMembershipListener, setMembershipService

Methods inherited from class java.lang.Object

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

Field Detail

sm

protected static final StringManager sm

String manager for this class.

CUSTOM_ENV_PREFIX

protected static final java.lang.String CUSTOM_ENV_PREFIX

Prefix for custom environment variables.

See Also:

Constant Field Values

url

protected java.lang.String url

The URL for the cloud membership service.

streamProvider

protected StreamProvider streamProvider

The provider for cloud API streams.

connectionTimeout

protected int connectionTimeout

Connection timeout in milliseconds.

readTimeout

protected int readTimeout

Read timeout in milliseconds.

startTime

protected java.time.Instant startTime

The time when this provider started.

headers

protected java.util.Map<java.lang.String,java.lang.String> headers

HTTP headers for cloud API requests.

localIp

protected java.lang.String localIp

The local IP address.

port

protected int port

The local port number.

expirationTime

protected long expirationTime

Member expiration time in milliseconds.

Constructor Detail

CloudMembershipProvider

public CloudMembershipProvider()

Default constructor.

Method Detail

digest

protected static byte[] digest(byte[] input)

Thread safe MD5 digest.

Parameters:

input - The bytes to digest

Returns:

The MD5 digest for the given input

getEnv

protected static java.lang.String getEnv(java.lang.String... keys)

Get value of environment variable.

Parameters:

keys - the environment variables

Returns:

the env variables values, or null if not found

getNamespace

protected java.lang.String getNamespace()

Get the Kubernetes namespace, or "tomcat" if the Kubernetes environment variable cannot be found (with a warning log about the missing namespace).

Returns:

the namespace

init

public void init(java.util.Properties properties)
          throws java.io.IOException

Description copied from interface: MembershipProvider

Initialize the membership provider with the specified configuration.

Specified by:

init in interface MembershipProvider

Overrides:

init in class MembershipProviderBase

Parameters:

properties - configuration

Throws:

java.io.IOException

start

public void start(int level)
           throws java.lang.Exception

Description copied from interface: MembershipProvider

Start the membership provider.

Specified by:

start in interface MembershipProvider

Parameters:

level - the readiness level

• Channel.DEFAULT - will start all services
• Channel.MBR_RX_SEQ - starts the membership receiver
• Channel.MBR_TX_SEQ - starts the membership broadcaster

Throws:

java.lang.Exception - if an error occurs

stop

public boolean stop(int level)
             throws java.lang.Exception

Description copied from interface: MembershipProvider

Stop the membership provider.

Specified by:

stop in interface MembershipProvider

Parameters:

level - the readiness level

• Channel.DEFAULT - will stop all services
• Channel.MBR_RX_SEQ - stops the membership receiver
• Channel.MBR_TX_SEQ - stops the membership broadcaster

Returns:

true if successful

Throws:

java.lang.Exception - if an error occurs

heartbeat

public void heartbeat()

Description copied from interface: Heartbeat

Heartbeat invocation for resources cleanup etc

Specified by:

heartbeat in interface Heartbeat

fetchMembers

protected abstract Member[] fetchMembers()

Fetch current cluster members from the cloud orchestration.

Returns:

the member array

updateMember

protected void updateMember(Member member,
                            boolean add)

Add or remove specified member.

Parameters:

member - the member to add

add - true if the member is added, false otherwise

messageReceived

public void messageReceived(java.io.Serializable msg,
                            Member sender)

Description copied from interface: ChannelListener

Receive a message from the channel

Specified by:

messageReceived in interface ChannelListener

Parameters:

msg - Serializable

sender - - the source of the message

accept

public boolean accept(java.io.Serializable msg,
                      Member sender)

Description copied from interface: ChannelListener

Invoked by the channel to determine if the listener will process this message or not.

Specified by:

accept in interface ChannelListener

Parameters:

msg - Serializable

sender - Member

Returns:

boolean