Follow pagination for >500 emoji

export.py

@@ -3,21 +3,19 @@
 # Export emoji in a Slack team as files
 # https://github.com/smashwilson/slack-emojinator
 
-import requests
-import lxml.html
-
+import aiohttp
 import argparse
-import os
-import shutil
-import asyncio, aiohttp
+import asyncio
 import logging
-
-from upload import _session
+import lxml.html
+import os
+from typing import List
 
 logging.basicConfig(level=logging.INFO, format="%(asctime)-15s\t%(message)s")
 logger = logging.getLogger(__name__)
 
-URL = "https://{team_name}.slack.com/customize/emoji"
+BASE_URL = 'https://{team_name}.slack.com'
+EMOJI_ENDPOINT = '/customize/emoji'
 
 
 def _argparse():
@@ -41,13 +39,15 @@ def _argparse():
     parser.add_argument(
         '--concurrent-requests', '-r',
         default=os.getenv('CONCURRENT_REQUESTS', 200),
+        type=int,
         help='Maximum concurrent requests. Defaults to the $CONCURRENT_REQUESTS environment variable or 200.'
     )
     args = parser.parse_args()
     return args
 
-def concurrent_http_get(num_chunks: int, session: aiohttp.ClientSession):
-    semaphore = asyncio.Semaphore(num_chunks)
+
+def concurrent_http_get(max_concurrent: int, session: aiohttp.ClientSession):
+    semaphore = asyncio.Semaphore(max_concurrent)
 
     async def http_get(url, name):
         nonlocal semaphore
@@ -56,47 +56,74 @@ async def http_get(url, name):
             body = await response.content.read()
             await response.wait_for_close()
         return body, name, url
+
     return http_get
 
-def handle_response(response, name: str, url: str, directory: str):
+
+def save_to_file(response, name: str, url: str, directory: str):
     logger.info(f"Got {name.ljust(15)} {url}")
     ext = url.split(".")[-1]
     with open(os.path.join(directory, f"{name}.{ext}"), 'wb') as out:
         out.write(response)
 
+
+def parse_emoji_from_page(text: str) -> List[str]:
+    '''Given the text of an HTML page, retrieve a list of (relative) URLs to emoji.
+    :param text Raw HTML.
+    :return ['/path/to/first.png', '/path/to/second.png', ...]'''
+    tree = lxml.html.fromstring(text)
+    urls = tree.xpath(r'//td[@headers="custom_emoji_image"]/span/@data-original')
+    return urls
+
+
 def _async_session(auth_cookie):
     return aiohttp.ClientSession(headers={"Cookie": auth_cookie})
 
+
 async def main():
     args = _argparse()
 
     if not os.path.exists(args.directory):
         os.makedirs(args.directory)
 
+    base_url = BASE_URL.format(team_name=args.team_name)
+    emoji_url = base_url + EMOJI_ENDPOINT
+
     async with _async_session(args.cookie) as session:
-        endpoint = URL.format(team_name=args.team_name)
-        logger.info(f"Getting {endpoint}")
-        resp = await session.get(endpoint)
-        async with resp:
-            if resp.status != 200:
-                logger.error(f"Failed to retrieve emoji list ({resp.status})")
+        logger.info(f"Getting {emoji_url}")
+
+        async with session.get(emoji_url) as base_page_q:
+            if base_page_q.status != 200:
+                logger.error(f"Failed to retrieve emoji list ({base_page_q.status})")
                 return
-            text = await resp.text()
+            text = await base_page_q.text()
             tree = lxml.html.fromstring(text)
-            urls = tree.xpath(r'//td[@headers="custom_emoji_image"]/span/@data-original')
-            names = [u.split('/')[-2] for u in urls]
 
-            logger.info(f"Parsed {len(names)} emojis")
-            assert len(names) > 0
+            emoji_urls = []
+            emoji_urls.extend(parse_emoji_from_page(text))
+            other_emoji_pages = [f"{base_url}{p}" for p in
+                                 tree.xpath(r'//div[@class="pagination pagination-centered"]'
+                                            r'/ul/li/a[.!="Next"]/@href[.!="#"]')
+                                 if p != EMOJI_ENDPOINT]
+            logger.info(f"Getting other emoji from: {other_emoji_pages}")
+            for emoji_page in other_emoji_pages:
+                async with session.get(f"{emoji_page}") as page:
+                    text = await page.text()
+                    emoji_urls.extend(parse_emoji_from_page(text))
+
+            emoji_names = [u.split('/')[-2] for u in emoji_urls]
+
+            logger.info(f"Parsed {len(emoji_names)} emojis")
+            assert len(emoji_names) > 0
 
         http_get = concurrent_http_get(args.concurrent_requests, session)
-        tasks = [http_get(emoji_url, emoji_name) for emoji_name, emoji_url in zip(names, urls) if "alias" not in emoji_url]
+        tasks = [http_get(emoji_url, emoji_name) for emoji_name, emoji_url in zip(emoji_names, emoji_urls)
+                 if "alias" not in emoji_url]
         for future in asyncio.as_completed(tasks):
             data, name, url = await future
-            handle_response(data, name, url, args.directory)
+            save_to_file(data, name, url, args.directory)
 
 
 if __name__ == '__main__':
     loop = asyncio.get_event_loop()
     loop.run_until_complete(main())
-