Metis Workflow Monitor
The Metis Workflow Monitor enables the activation and deactivation of instantiated workflows, and passes these requests to the execution engine. It also allows users to monitor the current status of the activated workflow, and provides an interface for enabling users to publish events to active workflows.
The home page of the Metis Workflow Monitor is shown below.
In the above example the Admin Workflow has been activated by the workflow monitor, by selecting the Workflow Name from the Available Workflows list and then clicking on the Activate Workflow button. Once this is done, the selected workflow is now activated and is visible in the Active Workflow list. Here the workflow name is appended with the timestamp so that the same workflow can be activated multiple times, and be considered as different workflow instances.
On selecting a workflow from the Active Workflows list and then clicking on Deactivate Workflow, the workflow is removed from the active list.
Selecting an active workflow and clicking on the View Status button, brings up the following page:
The Metis Workflow Viewer is used for 2 reasons:
- To view workflow status
- To publish events
The above workflow has two events in a sequence, and it is waiting for the first event submissionReceived to come in. Once this event is fired, the workflow will display it as a completed event and the next event submissionProcessed will be waiting for the event.
The second task of the Workflow Monitor is to provide an interface for publishing events.
On clicking on any Event, the listing of all its Attributes and Values is visible. Also the status of the Event is available. If the events status is Ready to be Published, the Values can be assigned to the Attributes and the event is published by clicking on the Publish button.
When an event is published, all the actions associated with that event are executed by the execution engine.
Once all the events for the activated workflow are published, and no more events are still pending, then the workflow is completed and reloading the display will take the user back to the Main Workflow Monitor Screen. The completed workflow will no longer be present in the Active Workflows list.
If an already published event is clicked on, it displays all its attributes and the values that were assigned to these attributes at the time it was published. Hence on selecting the event submissionReceived now, it is displayed as follows:
On clicking on an event that is still in the list of pending events, the Workflow Monitor displays only the list of attributes that are associated with this event.
When the user clicks on the root node, which in this case is Admin-Workflow, it displays the Workflow ID assigned to it.
When the user clicks on any node other than the root and event nodes, it displays the Node ID assigned to that node.
