at.environment

The at.environment namespace is how scripts read and write environment variables. Anything you set here is persisted to the active environment and is available in subsequent requests — both as the return value of at.environment.get() and as a {{varName}} placeholder in URLs, headers, bodies, query parameters, and auth fields.

Three Methods

  • •at.environment.get(key) — returns the value of the variable as a string, or undefined if it does not exist.
  • •at.environment.set(key, value) — writes a variable to the active environment. The value is coerced to a string. The change is visible to subsequent get() calls in the same script immediately, and is persisted to disk after the script finishes.
  • •at.environment.has(key) — returns true if the variable exists (either a pending write from this script, or an existing stored value), otherwise false.

Where Environment Variables Are Resolved

Variables stored via at.environment.set()(or defined from the Environment Manager) are referenced with the {{varName}} syntax and are resolved at request-build time in every field that supports variable interpolation:

  • •URL: https://{{base_url}}/api/users
  • •Headers: Authorization: Bearer {{token}}
  • •Request body: {"api_key":"{{api_key}}"}
  • •Query parameters: key={{api_key}}
  • •Authentication: Bearer token, Basic Auth, API Key fields.
  • •Flow assertions: the expected value side of an assertion.

Which Environment at.environment Reads

The environment that a script reads from and writes to depends on where the script is running:

  • •Standalone request (Box): the active global environment from the Environment Manager.
  • •Project request: the active environment of the project that owns the request.
  • •Flow step or Flow Before All / After All: the active environment of the flow group.
  • •Load test step or Load Test Before All / After All: the active environment of the load test folder.

Switching the active environment from the top bar changes which variables these scripts see the next time they run.

Pre-Script → Post-Script Bridging

When a pre-script calls at.environment.set("foo", "bar"), the post-script for the same request can immediately read that value back with at.environment.get("foo")— even though the write has not yet been persisted to disk. Atrahasis carries pre-script environment changes forward into the post-script as pending overrides, so the two scripts always agree on the state of the environment.

Example — Login Flow with Token Storage

Post-script on a login request:

// Extract tokens from a login response and save them to the environment.
if (at.response.status === 200) {
  const data = at.response.json();
  at.environment.set("auth_token", data.access_token);
  at.environment.set("refresh_token", data.refresh_token);
  at.environment.set("user_id", String(data.user.id));
  console.log("Tokens saved to environment");
}

// Subsequent requests can now use:
//   URL:    https://{{base_url}}/api/users/{{user_id}}
//   Header: Authorization: Bearer {{auth_token}}
Globalsat.flow