loadmill

Loadmill

Users of Loadmill can use this node module to:

1. Run load tests on loadmill.com.
2. Run functional tests on loadmill.com.
3. Do both programmatically or via CLI.

Installation

Using npm:

npm install loadmill --save

Using yarn:

yarn add loadmill

If you need to run the loadmill CLI outside of an npm script, you may prefer to install this package globally.

Using npm:

npm install -g loadmill

Using yarn:

yarn global add loadmill

Usage

The following code runs a very simple load test that gets a single page from www.myapp.com every second for one minute:

const loadmill = require('loadmill')({token: process.env.LOADMILL_API_TOKEN});

// You may also give a path to a valid JSON file instead:
loadmill.run({requests: [{url: "www.myapp.com"}]}, (err, id) => {
    if (!err) {
        console.log("Load test started: " + id);
    }
});

Test Configuration

The JSON test configuration may be exported from the loadmill test editor or from an old test run. Read more about the configuration format here.

Using Promises

Every function that accepts a callback will return a promise instead if no callback is provided (and vice versa):

loadmill.run("./load-tests/simple.json")
    .then(id => console.log("Load test started: ", id))
    .catch(err => console.error("Something bad: ", err));

Waiting for Tests

Since load tests usually run for at least a few minutes, the loadmill client does not wait for them to finish by default. You can explicitly wait for a test to finish using the wait function:

loadmill.run("./load-tests/long_test.json")
   .then(loadmill.wait)
   // -> {id: string, type: 'load', passed: boolean, url: string}
   .then(result => console.log(result));

Running multiple tests

In case you wish to run all the Loadmill tests in a given folder you can use the runFolder API. It will execute all the tests synchronously (using the wait option by default) unless a test has failed. This API returns an array of the tests result:

loadmill.runFolder("/path/to/tests/folder")
   // -> [{id: string, type: 'load', passed: boolean, url: string}]
       .then(results => console.log(results));

Functional Tests

You may also use a test configuration to run a functional test (i.e. a single iteration of requests) - this is usually useful for testing your API for regressions after every new deployment. Functional tests are expected to be shorter and thus are awaited on by default:

loadmill.runFunctional("./load-tests/api_test.json")
    // -> {id: string, type: 'functional', passed: boolean, url: string}
    .then(result => console.log(result));

If you wish to execute the tests from your local machine (rather than our SaaS infrastructure) you can use:

loadmill.runFunctionalLocally("./load-tests/api_test.json")
    // -> {type: 'functional', passed: boolean}
    .then(result => console.log(result));

If your functional test is supposed to, or may, take longer than 25 seconds, you can use runAsyncFunctional instead:

loadmill.runAsyncFunctional("./load-tests/api_test.json")
    // -> {id: string, type: 'functional', passed: null, url: string}
    .then(result => console.log(result));

Note that in this case the passed property is null since the promise resolves before the test is finished. If you want to wait for the full result you can use wait here as well:

loadmill.runAsyncFunctional("./load-tests/api_test.json")
    .then(loadmill.wait)
    // -> {id: string, type: 'functional', passed: boolean, url: string}
    .then(result => console.log(result));

In case you wish to run several functional tests in a given folder you can use the runFunctionalFolder API. It will execute all the tests in the folder synchronously unless a test has failed. This API returns an array of the tests result:

loadmill.runFunctionalFolder("/path/to/tests/folder")
    // -> [{id: string, type: 'functional', passed: boolean, url: string}]
    .then(result => console.log(result));

If you wish to execute all the tests in that folder from your local machine (rather than our SaaS infrastructure) you can use:

loadmill.runFunctionalFolderLocally("/path/to/tests/folder")
    // -> [{type: 'functional', passed: boolean}]
    .then(result => console.log(result));

Parameters

You will usually want some part of your test to be dynamic, e.g. the host name of the tested server. With Loadmill, this is made easy by using parameters. You may set/override parameter defaults for a test by passing a hash mapping parameter names to values:

// Parameters may come before or instead of a callback:
loadmill.run("./load-tests/parametrized_test.json", {host: "test.myapp.com", port: 4443}, (err, id) => {/*...*/});

// You may also use predefined parameter values as well:
loadmill.runFunctional("./load-tests/parametrized_test.json", {host: "test.${parentDomain}"});

CLI

The loadmill Command Line Interface basically wraps the functions provided by the node module:

loadmill <config-file-or-folder> -t <token> [options] [parameter=value...]

Functional Tests

The default is to run a functional test:

loadmill test.json --token DW2rTlkNmE6A3ax5LVTSDxv2Jfw4virjQpmbOaLG

Unless the -q option is set, the result JSON will be printed to the standard output.

Local Functional Tests

You can also run functional tests from your local machine using the -c or --local flag

loadmill local-test.json --local --token DW2rTlkNmE6A3ax5LVTSDxv2Jfw4virjQpmbOaLG

Using the -c or --local option will override other options like --load-test etc...

Load Tests

You may launch a load test by setting the -l or --load-test option:

loadmill test.json --load-test -t DW2rTlkNmE6A3ax5LVTSDxv2Jfw4virjQpmbOaLG

The load test will be launched and its unique identifier will be printed to the standard output. You may alternatively set the -w or --wait option in order to wait for the load test to finish, in which case only the result JSON will be printed out at the end:

loadmill test.json -lw -t DW2rTlkNmE6A3ax5LVTSDxv2Jfw4virjQpmbOaLG

Exit Status

Unless the -n or --no-bail option is set, the CLI process will exit with a nonzero exit code if the test had not passed. Other errors, such as invalid command line arguments or unavailable network will always give a nonzero exit status.

Parameters

You may set loadmill parameter values via command line arguments by passing name=value pairs:

loadmill parametrized_test.json host=test.myapp.com port=4443 -t DW2rTlkNmE6A3ax5LVTSDxv2Jfw4virjQpmbOaLG

CLI Options

Full list of command line options:

• -h, --help Output usage information.
• -t, --token <token> Provide a Loadmill API Token. You must provide a token in order to run tests.
• -l, --load-test Launch a load test. If not set, a functional test will run instead.
• -a, --async Run the test asynchronously - affects only functional tests. Use this if your test can take longer than 25 seconds (otherwise it will timeout).
• -w, --wait Wait for the test to finish. Functional tests are automatically waited on unless async flag is turned on.
• -n, --no-bail Return exit code 0 even if test fails.
• -q, --quiet Do not print out anything (except errors).
• -v, --verbose Print out extra information for debugging (trumps -q). In case of an error will print the entire test's requests otherwise will print only the failed request.
• -c, --local Execute functional test synchronously on local machine. This flag overrides load-test and async options.