marccarre · October 24, 2020 08:46 · Oct 24, 2020
diff --git a/list_kindle_releases.py b/list_kindle_releases.py
@@ -0,0 +1,82 @@
+#!/usr/bin/env python
+'''
+List all available versions of Kindle for Mac and Kindle for PC.
+Dependencies:
+- asyncio==3.4.3
+- aiohttp==3.6.3
+'''
+
+import os
+import sys
+import asyncio
+import aiohttp
+
+
+MAX_ATTEMPTS = int(os.environ.get('MAX_ATTEMPTS', 3))  # Maximum number of attempts per URL.
+RATE_LIMIT = int(os.environ.get('RATE_LIMIT', 64))  # Number of active requests at any given time.
+
+
+'''
+Build numbers (5XXXX) increment:
+- by 1000 for minor versions
+- by 1 for patch versions -- with gaps, as some builds are not released.
+'''
+VERSIONS = [
+    {'build': 55000, 'version': '1.26'},
+    {'build': 56000, 'version': '1.27'},
+    {'build': 57000, 'version': '1.28'},
+    {'build': 58000, 'version': '1.29'},
+    {'build': 59000, 'version': '1.30'},
+]
+
+
+'''
+For example:
+- Kindle 1.26
+  - https://s3.amazonaws.com/kindleforpc/55076/KindleForPC-installer-1.26.55076.exe
+  - https://s3.amazonaws.com/kindleformac/55093/KindleForMac-55093.dmg
+- Kindle 1.30
+  - https://s3.amazonaws.com/kindleforpc/59056/KindleForPC-installer-1.30.59056.exe
+  - https://s3.amazonaws.com/kindleformac/59055/KindleForMac-1.30.59055.dmg
+'''
+URL_PATTERNS = [
+    'https://s3.amazonaws.com/kindleforpc/{build}/KindleForPC-installer-{version}.{build}.exe',
+    'https://s3.amazonaws.com/kindleformac/{build}/KindleForMac-{build}.dmg',
+    'https://s3.amazonaws.com/kindleformac/{build}/KindleForMac-{version}.{build}.dmg',
+]
+
+
+async def main():
+    async with aiohttp.ClientSession() as session:
+        urls = await fetch_all(session)
+        print('\n'.join(sorted([url for url in urls if url])))
+
+
+async def fetch_all(session):
+    tasks = []
+    semaphore = asyncio.Semaphore(RATE_LIMIT)
+    for v in VERSIONS:
+        for build in range(v['build'], v['build'] + 1000):
+            for pattern in URL_PATTERNS:
+                url = pattern.format(build=build, version=v['version'])
+                task = asyncio.create_task(fetch(session, semaphore, url))
+                tasks.append(task)
+    results = await asyncio.gather(*tasks)
+    return results
+
+
+async def fetch(session, semaphore, url):
+    for attempt in range(1, MAX_ATTEMPTS + 1):
+        try:
+            async with semaphore:
+                response = await session.head(url)
+                return url if response.status == 200 else None
+        except Exception as e:
+            if attempt < MAX_ATTEMPTS:
+                print('Attempt #%d: Retrying on %s as got: %s.' % (attempt, url, e), file=sys.stderr)
+            else:
+                print('Failed on %s with: %s' % (url, e), file=sys.stderr)
+
+
+if __name__ == '__main__':
+    asyncio.run(main())