feat(cli): check for newer Manim Slides version (#85)

* chore(deps): drop support for Python 3.7

In link with the recent release of [Manim v0.17.0](https://github.com/ManimCommunity/manim/releases/tag/v0.17.0), Manim Slides drops support for Python 3.7.

* feat(cli): check for newer Manim Slides version

Uses same logic as manim to check for a new version

* fix(lib): reset correct version

* fix(ci): add type stubs for requests

manim_slides/__main__.py

@@ -1,22 +1,66 @@
+import json
+
 import click
+import requests
 from click_default_group import DefaultGroup
 
 from . import __version__
 from .convert import convert
+from .manim import logger
 from .present import list_scenes, present
 from .wizard import init, wizard
 
 
 @click.group(cls=DefaultGroup, default="present", default_if_no_args=True)
+@click.option(
+    "--notify-outdated-version/--silent",
+    " /-S",
+    is_flag=True,
+    default=True,
+    help="Check if a new version of Manim Slides is available.",
+)
 @click.version_option(__version__, "-v", "--version")
 @click.help_option("-h", "--help")
-def cli() -> None:
+def cli(notify_outdated_version: bool) -> None:
     """
     Manim Slides command-line utilities.
 
     If no command is specified, defaults to `present`.
     """
-    pass
+    # Code below is mostly a copy from:
+    # https://github.com/ManimCommunity/manim/blob/main/manim/cli/render/commands.py
+    if notify_outdated_version:
+        manim_info_url = "https://pypi.org/pypi/manim-slides/json"
+        warn_prompt = "Cannot check if latest release of Manim Slides is installed"
+        try:
+            req_info: requests.models.Response = requests.get(
+                manim_info_url, timeout=10
+            )
+            req_info.raise_for_status()
+            stable = req_info.json()["info"]["version"]
+            if stable != __version__:
+                click.echo(
+                    "You are using Manim Slides version "
+                    + click.style(f"v{__version__}", fg="red")
+                    + ", but version "
+                    + click.style(f"v{stable}", fg="green")
+                    + " is available."
+                )
+                click.echo(
+                    "You should consider upgrading via "
+                    + click.style("pip install -U manim-slides", fg="yellow")
+                )
+        except requests.exceptions.HTTPError:
+            logger.debug(f"HTTP Error: {warn_prompt}")
+        except requests.exceptions.ConnectionError:
+            logger.debug(f"Connection Error: {warn_prompt}")
+        except requests.exceptions.Timeout:
+            logger.debug(f"Timed Out: {warn_prompt}")
+        except json.JSONDecodeError:
+            logger.debug(warn_prompt)
+            logger.debug(f"Error decoding JSON from {manim_info_url}")
+        except Exception:
+            logger.debug(f"Something went wrong: {warn_prompt}")
 
 
 cli.add_command(convert)