Reduce verbose output and show only failing tests in Jest

Sometimes the output of running Jest unit tests is a bit too verbose, with the pass and fail statuses of all tests as well as the test coverage table.

To prevent outputting the code coverage report table, use:

jest --collectCoverage=false

(This assumes Jest is configured to show the code coverage report already.)

We can reduce the verbosity of the Jest output aside from the coverage table by using a custom reporter. Jest Silent Reporter is a good choice for this. To install it:

$ npm install jest-silent-reporter

Then run the tests with:

$ jest --reporters jest-silent-reporter

Now we will see only the failing test output.

The coverage report can still be shown after the silent reporter output.

So, for the minimum output possible we can combine the silent reporter and omit coverage report:

$ jest --collectCoverage=false --reporters jest-silent-reporter

We can add this command to our package.json to have the option to run a silent minimal output for all our tests easily, for example like this:

"scripts": {
  "unit:silent": "jest --reporters jest-silent-reporter --collectCoverage=false" 

Then we can just run:

$ npm run unit:silent



Send email to a mailing list using the Mailgun API with cURL

Mailgun provides one of the nicest APIs for email communication.

This example assumes we have a mailing list already created and want to send an email to all recipients via the Mailgun API.

The way to do this is to POST to /messages and use the mailing list address as the recipient address in the API call. Here is the call being made via cURL:

$ curl --request POST \
 --url \
 --form 'from=Name <>' \
 --form "text=My email body" \
 --form "subject=My email subject line" \
 --form \
 --form user=api:MY_API_KEY

Note that this API call uses form fields and not any JSON payload.

A successful response will look something like:

   "message": "Queued. Thank you.",
   "id": "..."