com.netflix.discovery
Class DefaultEurekaClientConfig

java.lang.Object
  com.netflix.discovery.DefaultEurekaClientConfig

All Implemented Interfaces:

EurekaClientConfig

public class DefaultEurekaClientConfig
extends java.lang.Object
implements EurekaClientConfig

A default implementation of eureka client configuration as required by EurekaClientConfig.

The information required for configuring eureka client is provided in a configuration file.The configuration file is searched for in the classpath with the name specified by the property eureka.client.props and with the suffix .properties. If the property is not specified, eureka-client.properties is assumed as the default.The properties that are looked up uses the namespace passed on to this class.

If the eureka.environment property is specified, additionally eureka-client-.properties is loaded in addition to eureka-client.properties.

Field Summary

static java.lang.String

DEFAULT_ZONE

Constructor Summary

DefaultEurekaClientConfig()

DefaultEurekaClientConfig(java.lang.String namespace)

Method Summary

java.lang.String	fetchRegistryForRemoteRegions() Comma separated list of regions for which the eureka registry information will be fetched.
java.lang.String[]	getAvailabilityZones(java.lang.String region) Gets the list of availability zones (used in AWS data centers) for the region in which this instance resides.
java.lang.String	getBackupRegistryImpl() Gets the name of the implementation which implements BackupRegistry to fetch the registry information as a fall back option for only the first time when the eureka client starts.
int	getEurekaConnectionIdleTimeoutSeconds() Indicates how much time (in seconds) that the HTTP connections to eureka server can stay idle before it can be closed.
int	getEurekaServerConnectTimeoutSeconds() Indicates how long to wait (in seconds) before a connection to eureka server needs to timeout.
java.lang.String	getEurekaServerDNSName() Gets the DNS name to be queried to get the list of eureka servers.This information is not required if the contract returns the service urls by implementing EurekaClientConfig.getEurekaServerServiceUrls(String).
java.lang.String	getEurekaServerPort() Gets the port to be used to construct the service url to contact eureka server when the list of eureka servers come from the DNS.This information is not required if the contract returns the service urls by implementing EurekaClientConfig.getEurekaServerServiceUrls(String).
int	getEurekaServerReadTimeoutSeconds() Indicates how long to wait (in seconds) before a read from eureka server needs to timeout.
java.util.List<java.lang.String>	getEurekaServerServiceUrls(java.lang.String myZone) Gets the list of fully qualified URLs to communicate with eureka server.
int	getEurekaServerTotalConnections() Gets the total number of connections that is allowed from eureka client to all eureka servers.
int	getEurekaServerTotalConnectionsPerHost() Gets the total number of connections that is allowed from eureka client to a eureka server host.
java.lang.String	getEurekaServerURLContext() Gets the URL context to be used to construct the service url to contact eureka server when the list of eureka servers come from the DNS.This information is not required if the contract returns the service urls by implementing EurekaClientConfig.getEurekaServerServiceUrls(String).
int	getEurekaServiceUrlPollIntervalSeconds() Indicates how often(in seconds) to poll for changes to eureka server information.
int	getInstanceInfoReplicationIntervalSeconds() Indicates how often(in seconds) to replicate instance changes to be replicated to the eureka server.
java.lang.String	getProxyHost() Gets the proxy host to eureka server if any.
java.lang.String	getProxyPort() Gets the proxy port to eureka server if any.
java.lang.String	getRegion() Gets the region (used in AWS datacenters) where this instance resides.
int	getRegistryFetchIntervalSeconds() Indicates how often(in seconds) to fetch the registry information from the eureka server.
boolean	shouldDisableDelta() Indicates whether the eureka client should disable fetching of delta and should rather resort to getting the full registry information.
boolean	shouldFetchRegistry() Indicates whether this client should fetch eureka registry information from eureka server.
boolean	shouldFilterOnlyUpInstances() Indicates whether to get the applications after filtering the applications for instances with only InstanceInfo.InstanceStatus.UP states.
boolean	shouldGZipContent() Indicates whether the content fetched from eureka server has to be compressed whenever it is supported by the server.
boolean	shouldLogDeltaDiff() Indicates whether to log differences between the eureka server and the eureka client in terms of registry information.
boolean	shouldPreferSameZoneEureka() Indicates whether or not this instance should try to use the eureka server in the same zone for latency and/or other reason.
boolean	shouldRegisterWithEureka() Indicates whether or not this instance should register its information with eureka server for discovery by others.
boolean	shouldUseDnsForFetchingServiceUrls() Indicates whether the eureka client should use the DNS mechanism to fetch a list of eureka servers to talk to.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_ZONE

public static final java.lang.String DEFAULT_ZONE

See Also:

Constant Field Values

Constructor Detail

DefaultEurekaClientConfig

public DefaultEurekaClientConfig()

DefaultEurekaClientConfig

public DefaultEurekaClientConfig(java.lang.String namespace)

Method Detail

getRegistryFetchIntervalSeconds

public int getRegistryFetchIntervalSeconds()

Description copied from interface: EurekaClientConfig

Indicates how often(in seconds) to fetch the registry information from the eureka server.

Specified by:

getRegistryFetchIntervalSeconds in interface EurekaClientConfig

Returns:

the fetch interval in seconds.

getInstanceInfoReplicationIntervalSeconds

public int getInstanceInfoReplicationIntervalSeconds()

Description copied from interface: EurekaClientConfig

Indicates how often(in seconds) to replicate instance changes to be replicated to the eureka server.

Specified by:

getInstanceInfoReplicationIntervalSeconds in interface EurekaClientConfig

Returns:

the instance replication interval in seconds.

getEurekaServiceUrlPollIntervalSeconds

public int getEurekaServiceUrlPollIntervalSeconds()

Description copied from interface: EurekaClientConfig

Indicates how often(in seconds) to poll for changes to eureka server information.

Eureka servers could be added or removed and this setting controls how soon the eureka clients should know about it.

Specified by:

getEurekaServiceUrlPollIntervalSeconds in interface EurekaClientConfig

Returns:

the interval to poll for eureka service url changes.

getProxyHost

public java.lang.String getProxyHost()

Description copied from interface: EurekaClientConfig

Gets the proxy host to eureka server if any.

Specified by:

getProxyHost in interface EurekaClientConfig

Returns:

the proxy host.

getProxyPort

public java.lang.String getProxyPort()

Description copied from interface: EurekaClientConfig

Gets the proxy port to eureka server if any.

Specified by:

getProxyPort in interface EurekaClientConfig

Returns:

the proxy port.

shouldGZipContent

public boolean shouldGZipContent()

Description copied from interface: EurekaClientConfig

Indicates whether the content fetched from eureka server has to be compressed whenever it is supported by the server. The registry information from the eureka server is compressed for optimum network traffic.

Specified by:

shouldGZipContent in interface EurekaClientConfig

Returns:

true, if the content need to be compressed, false otherwise.

getEurekaServerReadTimeoutSeconds

public int getEurekaServerReadTimeoutSeconds()

Description copied from interface: EurekaClientConfig

Indicates how long to wait (in seconds) before a read from eureka server needs to timeout.

Specified by:

getEurekaServerReadTimeoutSeconds in interface EurekaClientConfig

Returns:

time in seconds before the read should timeout.

getEurekaServerConnectTimeoutSeconds

public int getEurekaServerConnectTimeoutSeconds()

Description copied from interface: EurekaClientConfig

Indicates how long to wait (in seconds) before a connection to eureka server needs to timeout.

Note that the connections in the client are pooled by HttpClient and this setting affects the actual connection creation and also the wait time to get the connection from the pool.

Specified by:

getEurekaServerConnectTimeoutSeconds in interface EurekaClientConfig

Returns:

time in seconds before the connections should timeout.

getBackupRegistryImpl

public java.lang.String getBackupRegistryImpl()

Description copied from interface: EurekaClientConfig

Gets the name of the implementation which implements BackupRegistry to fetch the registry information as a fall back option for only the first time when the eureka client starts.

This may be needed for applications which needs additional resiliency for registry information without which it cannot operate.

Specified by:

getBackupRegistryImpl in interface EurekaClientConfig

Returns:

the class name which implements BackupRegistry.

getEurekaServerTotalConnections

public int getEurekaServerTotalConnections()

Description copied from interface: EurekaClientConfig

Gets the total number of connections that is allowed from eureka client to all eureka servers.

Specified by:

getEurekaServerTotalConnections in interface EurekaClientConfig

Returns:

total number of allowed connections from eureka client to all eureka servers.

getEurekaServerTotalConnectionsPerHost

public int getEurekaServerTotalConnectionsPerHost()

Description copied from interface: EurekaClientConfig

Gets the total number of connections that is allowed from eureka client to a eureka server host.

Specified by:

getEurekaServerTotalConnectionsPerHost in interface EurekaClientConfig

Returns:

total number of allowed connections from eureka client to a eureka server.

getEurekaServerURLContext

public java.lang.String getEurekaServerURLContext()

Description copied from interface: EurekaClientConfig

Gets the URL context to be used to construct the service url to contact eureka server when the list of eureka servers come from the DNS.This information is not required if the contract returns the service urls by implementing EurekaClientConfig.getEurekaServerServiceUrls(String).

The DNS mechanism is used when EurekaClientConfig.shouldUseDnsForFetchingServiceUrls() is set to true and the eureka client expects the DNS to configured a certain way so that it can fetch changing eureka servers dynamically.

The changes are effective at runtime.

Specified by:

getEurekaServerURLContext in interface EurekaClientConfig

Returns:

the string indicating the context URI of the eureka server.

getEurekaServerPort

public java.lang.String getEurekaServerPort()

Description copied from interface: EurekaClientConfig

Gets the port to be used to construct the service url to contact eureka server when the list of eureka servers come from the DNS.This information is not required if the contract returns the service urls by implementing EurekaClientConfig.getEurekaServerServiceUrls(String).

The DNS mechanism is used when EurekaClientConfig.shouldUseDnsForFetchingServiceUrls() is set to true and the eureka client expects the DNS to configured a certain way so that it can fetch changing eureka servers dynamically.

The changes are effective at runtime.

Specified by:

getEurekaServerPort in interface EurekaClientConfig

Returns:

the string indicating the port where the eureka server is listening.

getEurekaServerDNSName

public java.lang.String getEurekaServerDNSName()

Description copied from interface: EurekaClientConfig

Gets the DNS name to be queried to get the list of eureka servers.This information is not required if the contract returns the service urls by implementing EurekaClientConfig.getEurekaServerServiceUrls(String).

The DNS mechanism is used when EurekaClientConfig.shouldUseDnsForFetchingServiceUrls() is set to true and the eureka client expects the DNS to configured a certain way so that it can fetch changing eureka servers dynamically.

The changes are effective at runtime.

Specified by:

getEurekaServerDNSName in interface EurekaClientConfig

Returns:

the string indicating the DNS name to be queried for eureka servers.

shouldUseDnsForFetchingServiceUrls

public boolean shouldUseDnsForFetchingServiceUrls()

Description copied from interface: EurekaClientConfig

Indicates whether the eureka client should use the DNS mechanism to fetch a list of eureka servers to talk to. When the DNS name is updated to have additional servers, that information is used immediately after the eureka client polls for that information as specified in EurekaClientConfig.getEurekaServiceUrlPollIntervalSeconds().

Alternatively, the service urls can be returned EurekaClientConfig.getEurekaServerServiceUrls(String), but the users should implement their own mechanism to return the updated list in case of changes.

The changes are effective at runtime.

Specified by:

shouldUseDnsForFetchingServiceUrls in interface EurekaClientConfig

Returns:

true if the DNS mechanism should be used for fetching urls, false otherwise.

shouldRegisterWithEureka

public boolean shouldRegisterWithEureka()

Description copied from interface: EurekaClientConfig

Indicates whether or not this instance should register its information with eureka server for discovery by others.

In some cases, you do not want your instances to be discovered whereas you just want do discover other instances.

Specified by:

shouldRegisterWithEureka in interface EurekaClientConfig

Returns:

true if this instance should register with eureka, false otherwise

shouldPreferSameZoneEureka

public boolean shouldPreferSameZoneEureka()

Description copied from interface: EurekaClientConfig

Indicates whether or not this instance should try to use the eureka server in the same zone for latency and/or other reason.

Ideally eureka clients are configured to talk to servers in the same zone

The changes are effective at runtime at the next registry fetch cycle as specified by EurekaClientConfig.getRegistryFetchIntervalSeconds()

Specified by:

shouldPreferSameZoneEureka in interface EurekaClientConfig

Returns:

true if the eureka client should prefer the server in the same zone, false otherwise.

shouldLogDeltaDiff

public boolean shouldLogDeltaDiff()

Description copied from interface: EurekaClientConfig

Indicates whether to log differences between the eureka server and the eureka client in terms of registry information.

Eureka client tries to retrieve only delta changes from eureka server to minimize network traffic. After receiving the deltas, eureka client reconciles the information from the server to verify it has not missed out some information. Reconciliation failures could happen when the client has had network issues communicating to server.If the reconciliation fails, eureka client gets the full registry information.

While getting the full registry information, the eureka client can log the differences between the client and the server and this setting controls that.

The changes are effective at runtime at the next registry fetch cycle as specified by EurekaClientConfig.getRegistryFetchIntervalSeconds()

Specified by:

shouldLogDeltaDiff in interface EurekaClientConfig

Returns:

true if the eureka client should log delta differences in the case of reconciliation failure.

shouldDisableDelta

public boolean shouldDisableDelta()

Description copied from interface: EurekaClientConfig

Indicates whether the eureka client should disable fetching of delta and should rather resort to getting the full registry information.

Note that the delta fetches can reduce the traffic tremendously, because the rate of change with the eureka server is normally much lower than the rate of fetches.

The changes are effective at runtime at the next registry fetch cycle as specified by EurekaClientConfig.getRegistryFetchIntervalSeconds()

Specified by:

shouldDisableDelta in interface EurekaClientConfig

Returns:

true to enable fetching delta information for registry, false to get the full registry.

fetchRegistryForRemoteRegions

@Nullable
public java.lang.String fetchRegistryForRemoteRegions()

Description copied from interface: EurekaClientConfig

Comma separated list of regions for which the eureka registry information will be fetched. It is mandatory to define the availability zones for each of these regions as returned by EurekaClientConfig.getAvailabilityZones(String). Failing to do so, will result in failure of discovery client startup.

Specified by:

fetchRegistryForRemoteRegions in interface EurekaClientConfig

Returns:

Comma separated list of regions for which the eureka registry information will be fetched. null if no remote region has to be fetched.

getRegion

public java.lang.String getRegion()

Description copied from interface: EurekaClientConfig

Gets the region (used in AWS datacenters) where this instance resides.

Specified by:

getRegion in interface EurekaClientConfig

Returns:

AWS region where this instance resides.

getAvailabilityZones

public java.lang.String[] getAvailabilityZones(java.lang.String region)

Description copied from interface: EurekaClientConfig

Gets the list of availability zones (used in AWS data centers) for the region in which this instance resides.

The changes are effective at runtime at the next registry fetch cycle as specified by EurekaClientConfig.getRegistryFetchIntervalSeconds()

Specified by:

getAvailabilityZones in interface EurekaClientConfig

Parameters:

region - the region where this instance is deployed.

Returns:

the list of available zones accessible by this instance.

getEurekaServerServiceUrls

public java.util.List<java.lang.String> getEurekaServerServiceUrls(java.lang.String myZone)

Description copied from interface: EurekaClientConfig

Gets the list of fully qualified URLs to communicate with eureka server.

Typically the eureka server URLs carry protocol,host,port,context and version information if any. Example: http://ec2-256-156-243-129.compute-1.amazonaws.com:7001/eureka/v2/

The changes are effective at runtime at the next service url refresh cycle as specified by EurekaClientConfig.getEurekaServiceUrlPollIntervalSeconds()

Specified by:

getEurekaServerServiceUrls in interface EurekaClientConfig

Parameters:

myZone - the zone in which the instance is deployed.

Returns:

the list of eureka server service urls for eureka clients to talk to.

shouldFilterOnlyUpInstances

public boolean shouldFilterOnlyUpInstances()

Description copied from interface: EurekaClientConfig

Indicates whether to get the applications after filtering the applications for instances with only InstanceInfo.InstanceStatus.UP states.

The changes are effective at runtime at the next registry fetch cycle as specified by EurekaClientConfig.getRegistryFetchIntervalSeconds()

Specified by:

shouldFilterOnlyUpInstances in interface EurekaClientConfig

Returns:

true to filter, false otherwise.

getEurekaConnectionIdleTimeoutSeconds

public int getEurekaConnectionIdleTimeoutSeconds()

Description copied from interface: EurekaClientConfig

Indicates how much time (in seconds) that the HTTP connections to eureka server can stay idle before it can be closed.

In the AWS environment, it is recommended that the values is 30 seconds or less, since the firewall cleans up the connection information after a few mins leaving the connection hanging in limbo

Specified by:

getEurekaConnectionIdleTimeoutSeconds in interface EurekaClientConfig

Returns:

time in seconds the connections to eureka can stay idle before it can be closed.

shouldFetchRegistry

public boolean shouldFetchRegistry()

Description copied from interface: EurekaClientConfig

Indicates whether this client should fetch eureka registry information from eureka server.

Specified by:

shouldFetchRegistry in interface EurekaClientConfig

Returns:

true if registry information has to be fetched, false otherwise.