There are two types of Message Handlers in DataStage.
Project-Level Message Handlers: These are installed in an application directory per Engine and and aren't supported by MettleCI so should be migrated deployed manually.
Job-Level Message Handlers: There is a MettleCI plugin to support their deployment only. While MettleCI deploys Job Level Message Handler files The MettleCI’s CLI and Bamboo plugin suite provides support for automated deployment of this type Message Handler from a Project's Git repository, it doesn't . However, MettleCI Workbench doesn’t offer native check-in and deletion functions for them so they must be managed via command line Git.
Anti-Pattern
Message Handlers are not an asset of DataStage. See Note below for an explanation why.
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"You can use the IBM® InfoSphere® Information Server Manager (the deployment tool) to move, deploy, and control your IBM InfoSphere DataStage® and QualityStage® assets." However, message handlers cannot be managed individually using the IS Manager or istool command line tool. |
High-performing DataStage development teams rightly view message handlers as something that disguises poor coding or job design decisions. They are most often found in organizations that mandate that Jobs should run without warnings but with little else to encourage their developers to remediate the root cause. As a result, Jobs are often set to Abort (e.g. via an After Routine) if they generate warning messages. Unfortunately, this oftem leads to developers - especially those under pressure - applying message handlers to quickly get compliant and move on.
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as they are not “DataStage-native” assets (refer to The Problem With Message Handlers) and must be managed via an alternative Git client (inc. the Git CLI).
Message Handler Deployment Plug-In
There is a The Bamboo Plugin to support deployment of Job-Level Message Handlers : is dm-dsmsgh-plugin. Installing this plugin enables the DataStage Message Handlers Bamboo Task. The corresponding MettleCI CLI command is isx message-handlers (ISX Message-Handlers Command ).
The Plugin plugin includes a task that will read all Message Handlers that follow the "<Job Name>.msh" naming convention and "inject" them into the ISX file of the corresponding Job during deployment. The updated ISX file can then be deployed like normal, resulting in both the Job design and Job-Level Message Handler ending up in the target DataStage instance.
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All Job-Level Message Handlers in a particular DataStage Project will need to be added to the corresponding Git repository, alongside the existing ISX files. These files need to be named following the "
<Job Name>.msh" convention.Continuous Integration Build Plans and Deployment Environments in Bamboo will need to be updated to execute the new "DataStage Message Handlers Task" immediately before the "DataStage Incremental Deployment Task".
For After each Message Handler is added to Git, the corresponding <Job Name>.isx jobs need to be checked in to Git againyou will need to re-check-in the corresponding Jobs. This is necessary to ensure that the subsequent CI Build Plan deployment (triggered by the check-in) will process the Message Handler as necessary.
No changes change to Bamboo Deployment Environment configuration is required.
How
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To Obtain a Job's Message Handlers
Follow these steps to find the relevant Local.msh file for a given Job in the Information Server File System.
For exampleExample: There is a Job called “GR_ACCOUNTS_LOCAL"
Within the relevant Project filesystemdirectory, find the
RT_SC<Job Number>directory that corresponds to the Job. The simplest method is to use Director to open up a log entry for the Job then get the "Job No." entry from that dialog box.
Within the
RT_SC<Job Number>directory, find the Job-Level Message Handler config file (Local.msh)Once found, copy and rename that file to
GR_ACCOUNTS_LOCAL.mshand check it into Git alongside the existing ISX file
Once this file has been checked in, re-check in the corresponding Job. This ensures that automated deployments pick it up.
The (updated) Continuous Integration Bamboo Plan for the corresponding DataStage Project will be auto-triggered and must complete successfully. This will ensure that subsequent deployments to other downstream environments (e.g. Test, QA, Production) will include Job-Level Message Handlers.
Changes to CI Plans
Continuous Integration Build Plans in Bamboo will need to be updated to execute the "DataStage Message Handlers" Task.
Once you have deployed the dm-dsmsgh-plugin plugin .jar to Bamboo, you will be able to add a 'DataStage Message Handlers' Task to an existing Continuous Integration Build Plan.
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Both the 'Root ISX directory' and 'Root message handler directory' fields must contain the following text: datastage.
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