import { AWS_REGIONS_TO_RUN_TESTS } from './cci-utils';

import * as fs from 'fs-extra';

import path from 'path';

/**

* This script prints region assignment for an e2e test job.

* The algorithm takes input via environment variable - CODEBUILD_BATCH_BUILD_IDENTIFIER

* and computes deterministic region assignment by looking at position

* of build job in 'wait_for_ids.json' file.

* In order to reshuffle regions 'offset' constant below should be modified.

*

* If region is already assigned, i.e. CLI_REGION environment variable is set this script is pass-through.

*/

// if region is specified by job honor it.

let selectedRegion = process.env.CLI_REGION;

if (!selectedRegion) {

const jobId = process.env.CODEBUILD_BATCH_BUILD_IDENTIFIER;

if (!jobId) {

throw Error('CODEBUILD_BATCH_BUILD_IDENTIFIER environment variable must be set');

}

// Offset should be changed if we want re-shuffle regions.

const offset = 0;

const waitForIdsFilePath = path.join('.', 'codebuild_specs', 'wait_for_ids.json');

const jobIds = JSON.parse(fs.readFileSync(waitForIdsFilePath, 'utf-8')) as Array<string>;

let jobPosition = jobIds.indexOf(jobId);

if (jobPosition < 0) {

// this should never happen if PR checks pass, but just in case fall back to first region.

jobPosition = 0;

}

const regionIndex = (jobPosition + offset) % AWS_REGIONS_TO_RUN_TESTS.length;

selectedRegion = AWS_REGIONS_TO_RUN_TESTS[regionIndex];

}

console.log(selectedRegion);