Hey there! Let me walk you through exactly how Siren handles fetching and validating the current App Store version for your LOB application:

Siren relies on Apple's public App Store Lookup API to pull the latest version info, and here's the step-by-step flow:

• Query the App Store API: It constructs a request using your app's bundle ID, targeting Apple's lookup endpoint. Under the hood, the call looks something like this:

  https://itunes.apple.com/lookup?bundleId=your.app.bundle.id
  

• Parse the response: Once it receives the JSON response from Apple, Siren extracts the version value from the top-level results array—this is the most recent live version on the App Store.
• Grab the local app version: It fetches your app's currently installed version directly from the main bundle using code similar to:

  Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as? String
  

The library doesn't just do a basic string comparison—it uses semantic versioning logic to ensure accurate validation:

• Semantic version check: It breaks down both version strings (local vs. App Store) into major, minor, and patch components, then compares each part to determine if the App Store version is newer. This means versions like 1.10.0 are correctly recognized as newer than 1.9.0, which a plain string comparison would mess up.
• Strict mode option: If you enable strictVersionChecking in Siren's configuration, it will only flag an update if the App Store version is definitively higher, avoiding false positives from any version string formatting inconsistencies.
• Graceful error handling: If the API request fails (network issues, invalid bundle ID, etc.), Siren will silently skip the check by default. You can hook into delegate methods to handle these cases if you want custom behavior.

Since your app is hosted on a customer's enterprise app page, keep in mind that Siren is built for public App Store apps out of the box. But you can easily customize it to target your enterprise app store's endpoint if needed—just override the default API URL, and the core version comparison logic will still work as expected. Just make sure your bundle ID is correctly set in Siren's initial setup, as that's how it targets the right app entry.

内容的提问来源于stack exchange，提问作者SRK