call a REST API directly from Activiti

[indrajra]

Hi there, what is the best way to call a REST API directly from Activiti?

These links seem old and so curious to check if there are better ways. Writing a JAVA class (delegate) for every REST API doesn't seem to scale. Any thoughts, suggestions?

https://forums.manning.com/posts/list/26612.page
https://forums.activiti.org/content/calling-rest-api

Thanks in advance.

Cheers
Rajesh.R

[vasile_dirla]

Hi,
Personally I like the approach based on a ServiceTask with a java delegate.

More exactly what's the thing you don't like to this approach ?

[indrajra]

Apologies for replying late, Vasile - was on vacation. I was looking to have this platform open for newer tasks. In my use-cases, when we release software I do not know all the REST services my customer will consume. So, rolling out a delegate or asking customer to do this may not always work. Happy to hear suggestions/alternatives. Thank you!

[jbarrez]

In that case, you'd have to have a custom delegate that allows for generic REST calls and response processing.

[maudrid]

Not sure if it helps,we call REST services from script tasks using unirest.
We load the scripts from file, so they can be edited without changing or redeploying the processes.

[indrajra]

Good suggestions, thanks @maudrid, @jbarrez. Please do share any link that you're aware of - sample or a write-up.

[maudrid]

This is a script that I have shared with he rest of the developers in my team:

<code>
/*
* Javascript
* http://unirest.io/
* Hint: Use maven to download all the required jar files. Place them in the webapps/activiti-app/WEB-INF/lib.
* mvn dependency:resolve
*/

var objectvar = {};
objectvar.name='my name';
objectvar.subobj = {};
objectvar.subobj.testprop = 'test';

var Unirest = Java.type('com.mashape.unirest.http.Unirest');

var response = Unirest.post("http://httpbin.org/post").body(JSON.stringify(objectvar)).asJson();
var body = response.getBody().toString();
execution.setVariable('fullJSON', body);
var bodyObj = JSON.parse(body);
execution.setVariable('MyIp',bodyObj.origin);

/* Another example

var response = Unirest.post("http://httpbin.org/post")
  .header("accept", "application/json")
  .queryString("apiKey", "123")
  .field("parameter", "value")
  .field("foo", "bar")
  .asJson();
 
  */
</code>

[yogesh_prajapat]

I tried the same thing in my local.
I have added unitest jar in WEB-INF/lib folder.

but it showing me following error. can you please help on this ?


05:07:06,917 [http-nio-8080-exec-5] ERROR org.activiti.engine.impl.interceptor.CommandContext  - Error while closing command context
org.activiti.engine.ActivitiException: Can't find scripting engine for 'Call to service'
        at org.activiti.engine.impl.scripting.ScriptingEngines.getEngineByName(ScriptingEngines.java:124)
        at org.activiti.engine.impl.scripting.ScriptingEngines.evaluate(ScriptingEngines.java:85)
        at org.activiti.engine.impl.scripting.ScriptingEngines.evaluate(ScriptingEngines.java:73)
        at org.activiti.engine.impl.bpmn.behavior.ScriptTaskActivityBehavior.execute(ScriptTaskActivityBehavior.java:78)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationActivityExecute.execute(AtomicOperationActivityExecute.java:60)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationTransitionNotifyListenerStart.eventNotificationsCompleted(AtomicOperationTransitionNotifyListenerStart
.java:52)
        at org.activiti.engine.impl.pvm.runtime.AbstractEventAtomicOperation.execute(AbstractEventAtomicOperation.java:56)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AbstractEventAtomicOperation.execute(AbstractEventAtomicOperation.java:49)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationTransitionCreateScope.execute(AtomicOperationTransitionCreateScope.java:49)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationTransitionNotifyListenerTake.execute(AtomicOperationTransitionNotifyListenerTake.java:80)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationTransitionDestroyScope.execute(AtomicOperationTransitionDestroyScope.java:116)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationTransitionNotifyListenerEnd.eventNotificationsCompleted(AtomicOperationTransitionNotifyListenerEnd.jav
a:35)
        at org.activiti.engine.impl.pvm.runtime.AbstractEventAtomicOperation.execute(AbstractEventAtomicOperation.java:56)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AbstractEventAtomicOperation.execute(AbstractEventAtomicOperation.java:49)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.take(ExecutionEntity.java:475)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.take(ExecutionEntity.java:453)
        at org.activiti.engine.impl.bpmn.behavior.BpmnActivityBehavior.performOutgoingBehavior(BpmnActivityBehavior.java:140)
        at org.activiti.engine.impl.bpmn.behavior.BpmnActivityBehavior.performDefaultOutgoingBehavior(BpmnActivityBehavior.java:66)
        at org.activiti.engine.impl.bpmn.behavior.FlowNodeActivityBehavior.leave(FlowNodeActivityBehavior.java:44)
        at org.activiti.engine.impl.bpmn.behavior.FlowNodeActivityBehavior.execute(FlowNodeActivityBehavior.java:36)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationActivityExecute.execute(AtomicOperationActivityExecute.java:60)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationProcessStartInitial.eventNotificationsCompleted(AtomicOperationProcessStartInitial.java:45)
        at org.activiti.engine.impl.pvm.runtime.AbstractEventAtomicOperation.execute(AbstractEventAtomicOperation.java:56)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.pvm.runtime.AtomicOperationProcessStart.eventNotificationsCompleted(AtomicOperationProcessStart.java:64)
        at org.activiti.engine.impl.pvm.runtime.AbstractEventAtomicOperation.execute(AbstractEventAtomicOperation.java:56)
        at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:97)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:665)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:658)
        at org.activiti.engine.impl.persistence.entity.ExecutionEntity.start(ExecutionEntity.java:403)
        at org.activiti.engine.impl.cmd.StartProcessInstanceCmd.execute(StartProcessInstanceCmd.java:110)
        at org.activiti.engine.impl.cmd.StartProcessInstanceCmd.execute(StartProcessInstanceCmd.java:37)
        at org.activiti.engine.impl.interceptor.CommandInvoker.execute(CommandInvoker.java:24)
        at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:57)
        at org.activiti.spring.SpringTransactionInterceptor$1.doInTransaction(SpringTransactionInterceptor.java:47)
        at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133)
        at org.activiti.spring.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:45)
        at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:31)
        at org.activiti.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:40)
        at org.activiti.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:35)
        at org.activiti.engine.impl.RuntimeServiceImpl.startProcessInstanceById(RuntimeServiceImpl.java:118)
        at com.activiti.service.runtime.ActivitiService.startProcessInstance(ActivitiService.java:37)
        at com.activiti.service.runtime.ActivitiService$$FastClassBySpringCGLIB$$87164725.invoke(<generated>)
        at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
        at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
        at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
        at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
        at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
        at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
        at com.activiti.service.runtime.ActivitiService$$EnhancerBySpringCGLIB$$dcfe1f63.startProcessInstance(<generated>)
        at com.activiti.service.runtime.ProcessInstanceService.startNewProcessInstance(ProcessInstanceService.java:79)
        at com.activiti.service.runtime.ProcessInstanceService$$FastClassBySpringCGLIB$$82da82a2.invoke(<generated>)
        at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
        at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
        at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
        at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
        at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
        at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
        at com.activiti.service.runtime.ProcessInstanceService$$EnhancerBySpringCGLIB$$b40fb040.startNewProcessInstance(<generated>)
        at com.activiti.service.runtime.AlfrescoProcessInstanceService.startNewProcessInstance(AlfrescoProcessInstanceService.java:318)
        at com.activiti.rest.runtime.ProcessInstancesResource.startNewProcessInstance(ProcessInstancesResource.java:31)
        at com.activiti.rest.runtime.ProcessInstancesResource$$FastClassBySpringCGLIB$$c5b1caab.invoke(<generated>)
        at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
        at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
        at com.ryantenney.metrics.spring.TimedMethodInterceptor.invoke(TimedMethodInterceptor.java:48)
        at com.ryantenney.metrics.spring.TimedMethodInterceptor.invoke(TimedMethodInterceptor.java:34)
        at com.ryantenney.metrics.spring.AbstractMetricMethodInterceptor.invoke(AbstractMetricMethodInterceptor.java:59)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
        at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
        at com.activiti.rest.runtime.ProcessInstancesResource$$EnhancerBySpringCGLIB$$5c0337f6.startNewProcessInstance(<generated>)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
        at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:776)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
        at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:868)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
        at com.codahale.metrics.servlet.AbstractInstrumentedFilter.doFilter(AbstractInstrumentedFilter.java:97)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:316)
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:126)
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:90)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:114)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:122)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:149)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:168)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:48)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:205)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:120)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at com.activiti.security.CustomStatelessCSRFFilter.doFilterInternal(CustomStatelessCSRFFilter.java:68)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:64)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:91)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:53)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
        at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:213)
        at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:176)
        at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:344)
        at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:261)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:670)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.lang.Thread.run(Unknown Source)

[raki1497]

DELETE /enterprise/process-instances/{processInstanceId}/identitylinks/{family}/{identityId}/{type}

this is returning status 204 , can any one help me in getting 200 status for this