Re-run Service

wdio-rerun-service is a 3rd party package, for more information please see GitHub | npm

This service tracks failing tests and scenarios, allowing failing or unstable tests or scenarios to be re-run.

Re-run vs. Retry#

The retry logic built into WDIO for Cucumber and Mocha/Jasmine is helpful for handling flaky steps in Cucumber and flaky tests in Mocha/Jasmine. However, for Cucumber this does not take into account that some steps may not be able to retry and running them 2x could break the rest of the Scenario. Mocha/Jasmine is another story as the retry logic can be applied to an entire test, however, this is still done real-time and perhaps does not account for temporal issues or netework connectivity problems.

The main distinctions of the re-run:

will re-run an entire Cucumber Scenario by line number and not just the step
allows for an entire Spec file to be re-run after a main test execution is complete
can be copied and executed locally (retry cannot)
can be used in conjuction with retry methods
does not require code changes to apply retry method to flaky or problematic tests

It is recommended to take some time to evaluate the options available, often times, a mixed solution maybe the solution which will provide the best real and actionable results to developers.

Installation#

The easiest way is to add wdio-rerun-service to devDependencies in your package.json.

{
    "devDependencies": {
        "wdio-rerun-service": "^0.0.10"
    }
}

You can simple do it by:

npm install wdio-rerun-service

After package installation is complete, add it to services array:

// wdio.conf.js
const RerunService = require('wdio-rerun-service');
export.config = {
    // ...
    services: [RerunService],
    // ...
};

Instructions on how to install WebdriverIO can be found here.

Configuration#

The following options can be added to the wdio.conf.js file. To define options for the service you need to add the service to the services list in the following way:

// wdio.conf.js
const RerunService = require('wdio-rerun-service');
export.config = {
    // ...
    services: [
        [RerunService', {
            // Re-run service options here...
        }]
    ],
    // ...
};

rerunDataDir#

Directory where all the re-run JSON data will be kept during execution.

Type: String

Default: ./results/rerun

Example:

const RerunService = require('wdio-rerun-service');
export.config = {
    // ...
    services: [
        [RerunService', {
            rerunDataDir : './custom-rerun-directory'
        }]
    ],
    // ...
}

rerunScriptPath#

Path to write re-run Bash script.

Type: String

Default: ./rerun.sh

Example:

const RerunService = require('wdio-rerun-service');
export.config = {
    // ...
    services: [
        [RerunService', {
            rerunDataDir : './custom-path-for-rerun.sh'
        }]
    ],
    // ...
}

ignoredTags#

(Cucumber-only) Set of Cucumber tags, if scenario contains tag re-run service skip analysis.

Type: Array

Default: []

Example:

const RerunService = require('wdio-rerun-service');
export.config = {
    // ...
    services: [
        [RerunService', {
            ignoredTags: ['@known_bug']
        }]
    ],
    // ...
}

commandPrefix#

Prefix which will be added to the re-run command that is generated.

Type: String

Default: ''

Example:

const RerunService = require('wdio-rerun-service');
export.config = {
    // ...
    services: [
        [RerunService', {
            commandPrefix: "VARIABLE=true"
        }]
    ],
    // ...
}

For more information on WebdriverIO see the homepage.