Task cleanup with Defer

Learn how to use the Defer feature in Taskfile to ensure cleanup tasks are executed after the main task, even if it fails.

If you have multiple deferred commands, they will run in the reverse order. This means the last deferred command will run first, followed by the second last, and so on. This is useful for tasks that require a specific order of cleanup actions.

You can use the defer feature in Taskfile to ensure that a cleanup command runs after the main task, regardless of whether the task succeeded or failed. This is particularly useful for tasks that require cleanup actions, such as removing temporary files or directories.

Taskfile.yaml

version: '3'
tasks:
  install:
    cmds:
      - npm install
      - defer: rm -rf .cache
      - echo "Installation complete"
      - defer: echo "Cleanup task executed"

From this example, the rm -rf .cache command will run after the echo "Installation complete" command. defer will always run at the end of the task.

Demo and Output

ubuntu@touted-mite:~/nodejsfun$ task install 
task: [install] npm install
npm WARN EBADENGINE Unsupported engine {
npm WARN EBADENGINE   package: 'ansi-escapes@6.2.1',
npm WARN EBADENGINE   required: { node: '>=14.16' },
npm WARN EBADENGINE   current: { node: 'v12.22.9', npm: '8.5.1' }
npm WARN EBADENGINE }
npm WARN EBADENGINE Unsupported engine {
npm WARN EBADENGINE   package: 'marked-terminal@5.2.0',
npm WARN EBADENGINE   required: { node: '>=14.13.1 || >=16.0.0' },
npm WARN EBADENGINE   current: { node: 'v12.22.9', npm: '8.5.1' }
npm WARN EBADENGINE }
 
up to date, audited 185 packages in 1s
 
78 packages are looking for funding
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9 vulnerabilities (4 moderate, 5 high)
 
Some issues need review, and may require choosing
a different dependency.
 
Run `npm audit` for details.
task: [install] echo "Installation complete"
Installation complete
task: [install] echo "Cleanup task executed"
Cleanup task executed
task: [install] rm -rf .cache