IntegrationHub is a a powerful new feature provided by ServiceNow, allowing custom 'actions' to support a code-free or minimum code integration with outside systems. Being a new feature, there are some caveats as well as unexplained errors you may encounter either during development or when promoting to a higher environment. This article will cover some of the 'gotchas' that ServiceNow is currently working to correct and ensure that you can still take advantage of these features for your integration needs. Most of these issues are more common with a JDBC action but can also occur with REST and other custom activities in your flow.
Case 1: Workflow errors out at JDBC action with error: Failed to get plan context from MID
This error will likely occur after promoting your flow/action to the next environment. Although no root cause is currently known, this can be fixed by simply restarting the MID servers on that instance. Take note, unless you set it up that way specifically, your JDBC action will not use a designated MID but rather relies on an algorithm that will select the best available MID for use at that time. Restart all MID servers attached to your instance after your update set is committed and this error should resolve.
Case 2: Workflow errors out at JDBC action with error: Failed to get plan context from instance: <sys ID of Flow>
Another error that may occur once your flow hits an integration action appears to be a possible issue with the Flow Designer engine. The activity prior to your integration step may be designated as 'Completed' but the flow has not actually wrapped up what it was doing. This will cause your integration step to fail inexplicably before it initiates. The fix for this is to add a Timer activity prior to your integration step in the flow. The recommended wait time is approximately 5 seconds to ensure all prior activity is complete before your action is called.
Case 3: When an integration action occurs in your workflow, you receive an error regarding the credentials or alias attached to the action
This is another error with no known root cause. In our use case, we have exported the XMLs for the Connection, Credential, and Alias records for our JDBC step from development to the next environment. The workflow fails when it reaches the step. The fix for this is to recreate the Connection record when promoting to a higher environment. The credential and alias records should not cause a problem, but the imported connection will fail. Simply delete any that you have imported via XML, recreate, and attach your credential and alias. Manually update your Action in the Flow Designer to ensure that the alias used is the new one you have created.
Some of these example scenarios may pop up and provide no real error detail or documentation on the errors that are provided, denying you usability of the Flow Designer. Through trial and error, we have found that these workarounds are reliable and will allow full use of IntegrationHub until the bugs are worked out permanently.