Advanced Request Builder — CAPost Documentation

Building Complex Request Flows

The CAPost request builder seamlessly handles multiple complex authentication strategies and stateful test execution.

1. Advanced Authentication Support

OAuth2.0 Auto-Refresh: Automatically fetches, caches, and refreshes access_token credentials via implicit, authorization code, and client-credential grant flows.
AWS Signature Version 4 (SigV4): Native signing for requests targeting S3, DynamoDB, and CloudWatch.
mTLS & Client Certificates: Attach custom PEM certificate and private key pairs directly into the vault.

2. Pre-Request & Post-Response Scripts

Using the embedded QuickJS runtime, execute JavaScript to prepare payloads or extract tokens:

// Pre-Request QuickJS Script
function generateCSRFToken(request) {
    // Intercept response from API to grab CSRF token
    let res = postman.sendRequest({
        url: postman.getGlobalVariable("BASE_URL") + "/csrf",
        method: "GET"
    });
    let token = res.json().csrfToken;
    postman.setEnvironmentVariable("CSRF_TOKEN", token);
    request.headers.update({ "X-CSRF-TOKEN": token });
}

3. Sequential Chaining & Variables

Chain multiple API requests to extract values into execution variables:

Collection Variables: Available to all scripts within a workspace.
Execution Variables: Temporarily stored in RAM during a single runner cycle.
JSON Path / Regex Extraction: Automatically capture generated IDs like $.response.data.order_id to be used in subsequent API routes.