In MockServer expectations are only held in memory by default. However, it is possible to persist expectations to the local file system to ensure that they survive a restart of MockServer.

  1. persistExpectations configuration property needs to be set to true
  2. the file path used to persist expectations can be configured using the persistedExpectationsPath configuration property
  3. expectations should be initialised automatically using the initializationJsonPath configuration property

To ensure that the persisted expectations are loaded the next time MockServer starts the initializationJsonPath and persistedExpectationsPath should match and the persistExpectations should be set to true as follows:

MOCKSERVER_PERSIST_EXPECTATIONS=true \
MOCKSERVER_PERSISTED_EXPECTATIONS_PATH=mockserverInitialization.json \
MOCKSERVER_INITIALIZATION_JSON_PATH=mockserverInitialization.json \
java -jar ~/Downloads/mockserver-netty-5.12.0-shaded.jar -serverPort 1080,1081 -logLevel INFO

or

java \
-Dmockserver.persistExpectations=true \
-Dmockserver.persistedExpectationsPath=mockserverInitialization.json \
-Dmockserver.initializationJsonPath=mockserverInitialization.json \
-jar ~/Downloads/mockserver-netty-5.12.0-shaded.jar -serverPort 1080,1081 -logLevel INFO
 

Clustering MockServer

MockServer supports a very high request throughput, however if a higher request per second rate is required it is possible to cluster MockServer so that all nodes share expectations.

Although expectations are clustered, currently there is no support for clustering the MockServer log therefore request verifications will only work against the node that received the request.

To create a MockServer cluster all instances need to:

Each node could be configured as follows (adjusting the port as necessary):

MOCKSERVER_WATCH_INITIALIZATION_JSON=true \
MOCKSERVER_INITIALIZATION_JSON_PATH=mockserverInitialization.json \
MOCKSERVER_PERSIST_EXPECTATIONS=true \
MOCKSERVER_PERSISTED_EXPECTATIONS_PATH=mockserverInitialization.json \
java -jar ~/Downloads/mockserver-netty-5.12.0-shaded.jar -serverPort 1080 -logLevel INFO

or

java \
-Dmockserver.watchInitializationJson=true \
-Dmockserver.initializationJsonPath=mockserverInitialization.json \
-Dmockserver.persistExpectations=true \
-Dmockserver.persistedExpectationsPath=mockserverInitialization.json \
-jar ~/Downloads/mockserver-netty-5.12.0-shaded.jar -serverPort 1080 -logLevel INFO
 

Initialization & Persistence Configuration:

The class (and package) used to initialize expectations in MockServer at startup, if set MockServer will load and call this class to initialise expectations when is starts.

Type: string Default: null

Java Code:

ConfigurationProperties.initializationClass(String initializationClass)

System Property:

-Dmockserver.initializationClass=...

Environment Variable:

MOCKSERVER_INITIALIZATION_CLASS=...

Property File:

mockserver.initializationClass=...

Example:

-Dmockserver.initializationClass="org.mockserver.server.initialize.ExpectationInitializerExample"

The path to the json file used to initialize expectations in MockServer at startup, if set MockServer will load this file and initialise expectations for each item in the file when is starts.

The expected format of the file is a JSON array of expectations, as per the REST API format

Type: string Default: null

Java Code:

ConfigurationProperties.initializationJsonPath(String initializationJsonPath)

System Property:

-Dmockserver.initializationJsonPath=...

Environment Variable:

MOCKSERVER_INITIALIZATION_JSON_PATH=...

Property File:

mockserver.initializationJsonPath=...

Example:

-Dmockserver.initializationJsonPath=org/mockserver/server/initialize/initializerJson.json

If enabled the initialization json file will be watched for changes, any changes found will result in expectations being created, remove or updated by matching against their key.

If duplicate keys exist only the last duplicate key in the file will be processed and all duplicates except the last duplicate will be removed.

The order of expectations in the file is the order in which they are created if they are new, however, re-ordering existing expectations does not change the order they are matched against incoming requests.

Type: boolean Default: false

Java Code:

ConfigurationProperties.watchInitializationJson(boolean enable)

System Property:

-Dmockserver.watchInitializationJson=...

Environment Variable:

MOCKSERVER_WATCH_INITIALIZATION_JSON=...

Property File:

mockserver.watchInitializationJson=...

Example:

-Dmockserver.watchInitializationJson="org/mockserver/server/initialize/initializerJson.json"

Enable the persisting of expectations as json, which is updated whenever the expectation state is updated (i.e. add, clear, expires, etc)

Type: boolean Default: false

Java Code:

ConfigurationProperties.persistExpectations(boolean persistExpectations)

System Property:

-Dmockserver.persistExpectations=...

Environment Variable:

MOCKSERVER_PERSIST_EXPECTATIONS=...

Property File:

mockserver.persistExpectations=...

Example:

-Dmockserver.persistExpectations="true"

The file path used to save persisted expectations as json, which is updated whenever the expectation state is updated (i.e. add, clear, expires, etc)

Type: string Default: persistedExpectations.json

Java Code:

ConfigurationProperties.persistedExpectationsPath(String persistedExpectationsPath)

System Property:

-Dmockserver.persistedExpectationsPath=...

Environment Variable:

MOCKSERVER_PERSISTED_EXPECTATIONS_PATH=...

Property File:

mockserver.persistedExpectationsPath=...

Example:

-Dmockserver.persistedExpectationsPath="org/mockserver/server/initialize/initializerJson.json"