Paginate status results and implement rate limiting

Packages are chunked in groups of 100 to avoid generating too large
messages, and each chunk is sent spaced by 100 ms, to avoid rate
limiting.

In parallel, avoid room flooding by refusing to print statuses
with more than 50 repositories or 1000 packages.

Fixes issue #1.

oscbot/__init__.py

@@ -2,10 +2,12 @@
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
 from dataclasses import dataclass, field
+from time import sleep
 from typing import Optional, List, Type, Tuple
 
 import aiohttp
 import cryptocode
+import more_itertools as mit
 from lxml import objectify
 from jinja2 import BaseLoader, Environment
 
@@ -22,10 +24,8 @@ Only showing packages with {{ state }} state.
 
 {% endif %}"""
 
-REPO_TEMPLATE = """
-#### {{ repo.name }} - {{ repo.arch }}
-
-{% for package in repo.packages %}
+STATUS_TEMPLATE = """
+{% for package in packages %}
 {%if package.status != "disabled" %}
 {% set build_log_url = "{0}/package/live_build_log/{1}/{2}/{3}/{4}/".format(
     base_url, project, package.name, repo.name, repo.arch) %}
@@ -287,8 +287,29 @@ class OSCBot(Plugin):
 
         base_url = self.config["instance_url"]
 
+        if len(response) > 50:
+            await evt.respond(f"Too many repositories ({len(response)})"
+                              f"to display in project {project}, "
+                              "please narrow down your search.")
+            return
+
         for repository in response:
-            body = self.template.from_string(REPO_TEMPLATE)
-            message = body.render(repo=repository, project=project,
-                                  base_url=base_url)
-            await evt.respond(message, markdown=True)
+            await evt.respond(f"#### {repository.name} - {repository.arch}",
+                              markdown=True)
+
+            # Just so that someone doesn't flood by listing the whole
+            # openSUSE:Factory
+            if len(repository.packages) > 1000:
+                await evt.respond(
+                    f"Too many packages ({len(repository.packages)}) "
+                    "to display, please narrow down your search.")
+                continue
+            # To avoid creating too large messages, we chunk packages in
+            # groups of 100
+            for packagelist in mit.chunked(repository.packages, 100):
+                body = self.template.from_string(STATUS_TEMPLATE)
+                message = body.render(packages=packagelist, base_url=base_url,
+                                      project=project, repo=repository)
+                await evt.respond(message, markdown=True)
+                # Wait 100 milliseconds to avoid triggering rate limiting
+                sleep(0.1)