Recover from a failed step
Choose what happens when a node fails in a run: stop the flow, carry on with the error, try it again, or catch it with a Try/Catch node and go on.
Steps
Open How it runs
Open the node and click How it runs at the bottom of its settings. Closed, its line sums it up, such as Stops after 30 s · stops the flow on an error · tries again up to 2×.
Choose what a failure does
Under If it fails, pick:
- Stop the flow: a failed step fails the run.
- Carry on with the error: the node hands the error on as its output, and the run goes on.
With Try again automatically on, a step that fails for a passing reason, such as a busy service, is tried again first: Up to 2 more tries, waiting up to 1 s, then up to 30 s. A Condition, a Switch and a Raise error node have no If it fails.
Add a Try/Catch
To catch the failures of several nodes at once, type Try in Add a step and pick Try/Catch.
Link the nodes that may fail
| Port | Link to it |
|---|---|
| Try | The nodes that may fail. |
| If it worked | What runs when they all worked. |
| If it failed | The nodes that deal with a failure. |
When a step under Try fails, the run goes on through If it failed instead of failing, and shows that step as Caught. There, Input offers Error message, Error code and Failed step name.
To fail on purpose, such as when a booking is already taken, put a Raise error node under Try and write its Error message.
How it works
| Setting | What it does |
|---|---|
| Give up after | Set in seconds or minutes. A step that runs longer fails with NODE_TIMEOUT. |
| Try again automatically | A run starts a step at most three times. Each start is an attempt. |
| If Flowmage restarts | Flowmage restarted mid-step: a step that reads runs again; for one that writes, you choose Stop the run or Repeat (may happen twice). |
| Raise error | Its error code is FLOW_ERROR unless you set Error code under Advanced. |
If it did not work
- The run still stops at the node. Link it under Try, or set If it fails to Carry on with the error.
- "Error message is required." A Raise error node needs a message before you can publish.
- The step fails with NODE_TIMEOUT. The service took longer than Give up after. Raise it, or check the service.