An example of heavily automated, optimized, effective Postman collection level pre-request script

postman-collection-level-optimised-pre-request-script.js

// Remove collection name from the breadcrumb
pm.execution.location.splice(0, 1);

// Remove the last element as it is the request and we don't need it
pm.execution.location.pop();

let currentLocation = pm.execution.location.map(item => item.replace(/^((\d+\.\d*)(\s+))/, '').toLowerCase().split(' ').join('_')).join('_') || pm.variables.replaceIn('{{$uuid}}');
console.log('computed current location', currentLocation);

// set collection level current location to use it in all request and responses in this collection and it also mean it is self-contained
pm.collectionVariables.set('computed_current_location', currentLocation);

// If no Joomla API }Token provided do not continue
pm.test(`Pre-request setting default headers for ${currentLocation}`, () => {
    if (!pm.variables.get('auth_apikey')) {
        pm.expect.fail('This failed because no Joomla API Token provided');
    }
});


pm.test(`Pre-request setting default headers for ${currentLocation}`, () => {
    let method = pm.request.method;
    const allowedHttpAcceptHeader = ['application/vnd.api+json'];
    const allowedHttpContentTypeHeader = ['application/json'];

    const defaultHttpAcceptHeader = pm.variables.get('default_http_accept_header_value') || 'application/vnd.api+json';
    const defaultHttpContentTypeHeader = pm.variables.get('default_http_accept_header_value') || 'application/json';

    // Verify that the variables are in allowed lists
    pm.expect(allowedHttpAcceptHeader).to.include(defaultHttpAcceptHeader);
    pm.expect(allowedHttpContentTypeHeader).to.include(defaultHttpContentTypeHeader);

    // If not in allowed list stop here
    if (!allowedHttpAcceptHeader.includes(defaultHttpAcceptHeader) || !allowedHttpContentTypeHeader.includes(defaultHttpContentTypeHeader)) {
        pm.expect.fail('This failed because provided Accept header or Content-Type header is not allowed');
    }

    if (!['OPTIONS', 'HEAD', 'DELETE', 'TRACE'].includes(method) && !pm.request.headers.has('Accept', defaultHttpAcceptHeader)) {
        pm.request.headers.append('Accept', defaultHttpAcceptHeader);
    }

    if (['POST', 'PATCH', 'PUT'].includes(method)) {
        if (!pm.request.headers.has('Content-Type', defaultHttpContentTypeHeader)) {
            pm.request.headers.append('Content-Type', defaultHttpContentTypeHeader);
        }
    }
});