In OMIQ, tasks are locked as some tasks depend on these settings for their results. For example, computed tasks like peacoQC, FlowSOM, UMAP, etc and Export stats will depend on upstream tasks.
Therefore, in order to keep the results true to the settings that generated them, certain tasks are locked in OMIQ.
Overview
Task locks protect the dependencies inside an OMIQ workflow. When a downstream task relies on the settings of an upstream task, OMIQ locks those upstream settings so they cannot be changed in a way that would invalidate the downstream result. This article explains what locks are, why they appear, and how to safely override a lock when you need to add a gate or edit a locked task.
What a Task Lock is
A lock icon appears on certain tasks in a workflow. The message that accompanies it explains, very simply, that the task is locked because changing its settings may invalidate downstream results.
The purpose of the lock is to hold the configuration and settings of upstream tasks in place while downstream tasks depend on them.
For example, an UMAP result depends on the settings of the upstream Subsampling task, the Gating task and the Scaling task. Changing any of these in certain ways could make the UMAP result unreproducible, or produce an error in OMIQ where the result can no longer be recalled, because some results are computed dynamically.
Why locks sometimes get in the way
Locks exist for safety, but they are deliberately crude. They prevent changes to a locked task even when those changes would not actually endanger the downstream results.
A common example is adding a gate. Suppose your Gating task originally contained only a cleanup gate on CD45, because that was all that was needed at the time to run UMAP and build your figures. If you later want to start adding gates, for instance selecting CD45 and then drawing a population you consider to be CD3+, OMIQ will return an error when you try to save. This happens because the task downstream of the Gating task is locked.
Adding a gate does not genuinely threaten the rest of the workflow, but the lock cannot make that distinction.
How to override a lock
For tasks that support it, OMIQ offers the ability to unlock the task manually.
- Open the locked task you want to edit.
- Select the option to unlock the task.
- Read the warning that appears. It describes the risks of editing a task that downstream results depend on.
- Confirm the warning to place the task into an unlocked state.
- Make your change and save. While the task is unlocked it will save successfully.
In the example above, the new CD3 gate that was disallowed while the task was locked can now be inserted once the task has been unlocked.
You will find the Unlock Task option in the Gating, Compensation and Unmixing tasks.
Using the newly added gate
Once the gate has been inserted into the workflow, it becomes available to downstream tasks. You can return to a figure you have already built, open the menu that gives access to the filters, and the gate you just inserted will appear there, ready to use.
Be careful when overriding locks.
They are there for your protection. Editing an upstream task that a downstream task depends on can create serious problems, including unreproducible or unrecoverable results. Only unlock a task when you are confident the change is safe, such as adding a gate that does not alter the inputs the downstream tasks rely on.