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

Field Summary

Fields

Modifier and Type	Field	Description
protected int	connectionTimeout
protected static final String	CUSTOM_ENV_PREFIX
protected long	expirationTime
protected Map<String,String>	headers
protected String	localIp
protected MessageDigest	md5
protected int	port
protected int	readTimeout
protected static final StringManager	sm
protected Instant	startTime
protected StreamProvider	streamProvider
protected String	url

Fields inherited from class MembershipProviderBase

executor, membership, membershipListener, service

Constructor Summary

Constructors

Constructor	Description
CloudMembershipProvider()

Method Summary

Modifier and Type	Method	Description
boolean	accept(Serializable msg, Member sender)	Invoked by the channel to determine if the listener will process this message or not.
protected abstract Member[]	fetchMembers()	Fetch current cluster members from the cloud orchestration.
protected static String	getEnv(String... keys)	Get value of environment variable.
protected 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(Properties properties)	Initialize the membership provider with the specified configuration.
void	messageReceived(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 MembershipProviderBase

getMember, getMembers, hasMembers, setMembershipListener, setMembershipService

Methods inherited from class Object

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

Field Details

sm

protected static final StringManager sm

CUSTOM_ENV_PREFIX

protected static final String CUSTOM_ENV_PREFIX

See Also:

• Constant Field Values

url

protected String url

streamProvider

protected StreamProvider streamProvider

connectionTimeout

protected int connectionTimeout

readTimeout

protected int readTimeout

startTime

protected Instant startTime

md5

protected MessageDigest md5

headers

protected Map<String,String> headers

localIp

protected String localIp

port

protected int port

expirationTime

protected long expirationTime

Constructor Details

CloudMembershipProvider

public CloudMembershipProvider()

Method Details

getEnv

protected static String getEnv(String... keys)

Get value of environment variable.

Parameters:

keys - the environment variables

Returns:

the env variables values, or null if not found

getNamespace

protected 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(Properties properties)
          throws 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:

IOException

start

public void start(int level)
           throws 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:

Exception - if an error occurs

stop

public boolean stop(int level)
             throws 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:

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(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(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