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Custom Templates
Typescript Templates

Although you can write test templates in Javascript, we highly recommend writing your templates in Typescript to make everything more seamless.

A Test Template has 3 Components:

  • name - A name for your template
  • version - The version for your template
  • builder - A function that takes an endpoint and returns a TestBuilder

It’s structured like this in typescript:

TypeScript
import {
  AssertionType,
  GenTestEndpoint,
  TestBuilder,
  TestStepBuilder,
} from "@metlo/testing";

export default {
  name: "<YOUR_TEMPLATE_NAME>",
  version: <YOUR_TEMPLATE_VERSION>,
  builder: (endpoint: GenTestEndpoint) => {
    return new TestBuilder()
  },
}

​
Builder

A builder is a function that takes an endpoint of type GenTestEndpoint.

TypeScript
export interface GenTestEndpoint {
  host: string;
  path: string;
  method: Method;
  dataFields: GenTestEndpointDataField[];
  authConfig?: GenTestEndpointAuthConfig;
}

You can use this endpoint to generate a test with the TestBuilder class inside the function.

​
TestBuilder

Think of the test builder class as building up a YAML test file piece by piece by chaining the following functions:

​
setMeta - Adding Metadata

Use this function to add any metadata related to your test, generally you would want to add a name and severity.

TypeScript
return new TestBuilder().setMeta({
  name: `${endpoint.path} Custom Test`,
  severity: "MEDIUM",
  tags: ["SOME", "CUSTOM", "TEST", "TAGS"],
});

​
addToEnv - Adding Environment Variables

Add any environment variables you want to use later in your test.

TypeScript
return new TestBuilder()
  .setMeta(...)
  .addToEnv({ name: "some_env_var", value: "foo" });

​
addTestStep - Adding a Test Step

Use this function to add each request, along with its extractors and and assertions.

TypeScript
return new TestBuilder()
  .setMeta(...)
  .addToEnv(...)
  .addTestStep(
    new TestStepBuilder({
      method: endpoint.method,
      url: `https://${endpoint.host}${endpoint.path}`,
    }).assert({
      type: AssertionType.EQ,
      key: "resp.status",
      value: 200,
    })
  );

​
TestStepBuilder

The TestStepBuilder builds a request along with its assertions and extractors. You instantiate a test step builder with the request that you want to create:

TypeScript
new TestStepBuilder({
  method: ...,
  url: ...,
  data: ...,
  query: [ { value: ..., name: ... } ],
  headers: [ { value: ..., name: ... } ],
  form: [ { value: ..., name: ... } ],
})

You can also autogenerate a request using the endpoint using:

TypeScript
TestStepBuilder.sampleRequest(endpoint);

There are many cases where you would want to generate a sample request without any authentication:

TypeScript
TestStepBuilder.sampleRequestWithoutAuth(endpoint);

After that you can chain the following functions to create your step:

​
assert - Add an Assertion

Use this function to add an assertion to your test step.

TypeScript
import { AssertionType } from "@metlo/testing";

TestStepBuilder.sampleRequestWithoutAuth(endpoint).assert({
  type: AssertionType.EQ,
  key: "resp.status",
  value: [401, 403],
});

​
extract - Add an Extractor

Use this function to add an extractor to your test step.

TypeScript
import { ExtractorType } from "@metlo/testing";

TestStepBuilder.sampleRequest(endpoint)
  .assert(...)
  .extract({
    name: "step_1_status",
    value: "resp.status",
  })
  .extract({
    name: "html_element",
    type: ExtractorType.HTML,
    value: "#content-container > div.markdown-body.ng-non-bindable",
  })