Files
privacy.sexy/tests/integration/application/collections/StatusChecker/README.md
undergroundwires 82c43ba2e3 Refactor to remove "Async" function name suffix
Remove convention where Async suffix is added to functions that returns
a Promise. It was a habit from C#, but is not widely used in JavaScript
/ TypeScript world, also bloats the code. The code is more consistent
with third party dependencies/frameworks without the suffix.
2021-11-01 19:02:22 +01:00

3.9 KiB

status-checker

CLI and SDK to check whether an external URL is alive.

🧐 Why?

  • 🏃🏻 Batch checking status of URLs in parallel.
  • 🤖 Zero-touch start, pre-configured for reliable results, still configurable.
  • 🤞 Reliable, mimics a real web browser by following redirect, and cookie storage.

🍭 Sweets such as

  • 😇 Queueing requests by domain to be nice to them
  • 🔁 Retry pattern with exponential back-off

CLI

Coming soon 🚧

Programmatic usage

Programmatic usage is supported both on Node.js and browser.

getUrlStatusesInParallel

// Simple example
const statuses = await getUrlStatusesInParallel([ 'https://privacy.sexy', /* ... */ ]);
if(statuses.all((r) => r.code === 200)) {
    console.log('All URLs are alive!');
} else {
    console.log('Dead URLs:', statuses.filter((r) => r.code !== 200).map((r) => r.url));
}

// Fastest configuration
const statuses = await getUrlStatusesInParallel([ 'https://privacy.sexy', /* ... */ ], {
    domainOptions: {
        sameDomainParallelize: false,
    }
});

Batch request options

  • domainOptions:
    • sameDomainParallelize, (boolean), default: false
      • Determines whether the requests to URLs under same domain will be parallelize.
      • Setting false parallelizes all requests.
      • Setting true sends requests in queue for each unique domain, still parallelizing for different domains.
      • Requests to different domains are always parallelized regardless of this option.
      • 💡 This helps to avoid 429 Too Many Requests and be nice to websites
    • sameDomainDelayInMs (boolean), default: 3000 (3 seconds)
      • Sets delay between requests to same host (domain) if same domain parallelization is disabled.
  • requestOptions (object): See request options.

getUrlStatus

Checks whether single URL is dead or alive.

// Simple example
const status = await getUrlStatus('https://privacy.sexy');
console.log(`Status code: ${status.code}`);

Request options

  • retryExponentialBaseInMs (boolean), default: 5000 (5 seconds)
    • The based time that's multiplied by exponential value for exponential backoff and retry calculations
    • The longer it is, the longer the delay between retries are.
  • additionalHeaders (boolean), default: false
    • Additional headers that will be sent alongside default headers mimicking browser.
    • If default header are specified, additional headers override defaults.
  • followOptions (object): See follow options.

fetchFollow

Gets response from single URL by following 3XX redirect targets by sending necessary cookies.

Same fetch API except third parameter that specifies follow options, redirect: 'follow' | 'manual' | 'error' is discarded in favor of the third parameter.

const status = await fetchFollow('https://privacy.sexy', {
        // First argument is same options as fetch API, except `redirect` options
        // that's discarded in favor of next argument follow options
        headers: {
            'user-agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:47.0) Gecko/20100101 Firefox/47.0'
        },
    }, {
        // Second argument sets the redirect behavior
        followRedirects: true,
        maximumRedirectFollowDepth: 20,
        enableCookies: true,
    }
);
console.log(`Status code: ${status.code}`); 

Follow options

  • followRedirects (boolean), default: true
    • Determines whether redirects with 3XX response code will be followed.
  • maximumRedirectFollowDepth (boolean), default: 20
    • Determines maximum consequent redirects that will be followed.
    • 💡 Helps to solve maximum redirect reached errors.
  • enableCookies (boolean), default: true
    • Saves cookies requested to store by webpages and sends them when redirected.
    • 💡 Helps to over-come sign-in challenges with callbacks.