Make fancy functions for database & http stuff, meme preview

didier/cogs/fun.py

@@ -8,6 +8,7 @@ from database.crud.dad_jokes import get_random_dad_joke
 from database.crud.memes import get_meme_by_name
 from didier import Didier
 from didier.data.apis.imgflip import generate_meme
+from didier.exceptions.no_match import expect
 from didier.views.modals import GenerateMeme
 
 
@@ -22,6 +23,12 @@ class Fun(commands.Cog):
     def __init__(self, client: Didier):
         self.client = client
 
+    async def _do_generate_meme(self, meme_name: str, fields: list[str]) -> str:
+        async with self.client.postgres_session as session:
+            result = expect(await get_meme_by_name(session, meme_name), entity_type="meme", argument=meme_name)
+            meme = await generate_meme(self.client.http_session, result, fields)
+            return meme
+
     @commands.hybrid_command(
         name="dadjoke",
         aliases=["Dad", "Dj"],
@@ -37,26 +44,22 @@ class Fun(commands.Cog):
     async def memegen_msg(self, ctx: commands.Context, meme_name: str, *, fields: str):
         """Command group for meme-related commands"""
         async with ctx.typing():
-            async with self.client.postgres_session as session:
-                result = await get_meme_by_name(session, meme_name)
+            meme = await self._do_generate_meme(meme_name, shlex.split(fields))
+            return await ctx.reply(meme, mention_author=False)
 
-            if result is None:
-                return await ctx.reply(f"Found no meme matching `{meme_name}`.", mention_author=False)
-
-            meme = await generate_meme(self.client.http_session, result, shlex.split(fields))
-            if meme is None:
-                return await ctx.reply("Something went wrong.", mention_author=False)
-
-            return await ctx.reply(meme)
+    @memegen_msg.command(name="Preview", aliases=["P"])
+    async def memegen_preview_msg(self, ctx: commands.Context, meme_name: str):
+        """Generate a preview for a meme, to see how the fields are structured"""
+        async with ctx.typing():
+            fields = [f"Field #{i + 1}" for i in range(20)]
+            meme = await self._do_generate_meme(meme_name, fields)
+            return await ctx.reply(meme, mention_author=False)
 
     @memes_slash.command(name="generate", description="Generate a meme")
     async def memegen_slash(self, interaction: discord.Interaction, meme: str):
         """Slash command to generate a meme"""
         async with self.client.postgres_session as session:
-            result = await get_meme_by_name(session, meme)
-
-        if result is None:
-            return await interaction.response.send_message(f"Found no meme matching `{meme}`.", ephemeral=True)
+            result = await expect(get_meme_by_name(session, meme), entity_type="meme", argument=meme)
 
         modal = GenerateMeme(self.client, result)
         await interaction.response.send_modal(modal)

didier/data/apis/imgflip.py

@@ -1,10 +1,9 @@
-from typing import Optional
-
 from aiohttp import ClientSession
 
 import settings
 from database.schemas.relational import MemeTemplate
 from didier.exceptions.missing_env import MissingEnvironmentVariable
+from didier.utils.http.requests import ensure_post
 
 __all__ = ["generate_meme"]
 
@@ -20,7 +19,7 @@ def generate_boxes(meme: MemeTemplate, fields: list[str]) -> list[str]:
     return fields
 
 
-async def generate_meme(http_session: ClientSession, meme: MemeTemplate, fields: list[str]) -> Optional[str]:
+async def generate_meme(http_session: ClientSession, meme: MemeTemplate, fields: list[str]) -> str:
     """Make a request to Imgflip to generate a meme"""
     name, password = settings.IMGFLIP_NAME, settings.IMGFLIP_PASSWORD
 
@@ -36,9 +35,5 @@ async def generate_meme(http_session: ClientSession, meme: MemeTemplate, fields:
     for i, box in enumerate(boxes):
         payload[f"boxes[{i}][text]"] = box
 
-    async with http_session.post("https://api.imgflip.com/caption_image", data=payload) as response:
-        if response.status != 200:
-            return None
-
-        data = await response.json()
-        return data["data"]["url"]
+    async with ensure_post(http_session, "https://api.imgflip.com/caption_image", payload=payload) as response:
+        return response["data"]["url"]

didier/exceptions/http_exception.py

@@ -0,0 +1,8 @@
+__all__ = ["HTTPException"]
+
+
+class HTTPException(RuntimeError):
+    """Error raised when an API call fails"""
+
+    def __init__(self, status_code: int):
+        super().__init__(f"Something went wrong (status {status_code}).")

didier/exceptions/no_match.py

@@ -0,0 +1,24 @@
+from typing import Optional, TypeVar
+
+__all__ = ["NoMatch", "expect"]
+
+
+class NoMatch(ValueError):
+    """Error raised when a database lookup failed"""
+
+    def __init__(self, entity_type: str, argument: str):
+        super().__init__(f"Found no {entity_type} matching `{argument}`.")
+
+
+T = TypeVar("T")
+
+
+def expect(instance: Optional[T], *, entity_type: str, argument: str) -> T:
+    """Mark a database instance as expected, otherwise raise a custom exception
+
+    This is not just done in the database layer because it's not always preferable
+    """
+    if instance is None:
+        raise NoMatch(entity_type, argument)
+
+    return instance

didier/utils/http/requests.py

@@ -0,0 +1,56 @@
+import logging
+from contextlib import asynccontextmanager
+from typing import AsyncGenerator
+
+from aiohttp import ClientResponse, ClientSession
+
+from didier.exceptions.http_exception import HTTPException
+
+logger = logging.getLogger(__name__)
+
+
+__all__ = ["ensure_get", "ensure_post"]
+
+
+def request_successful(response: ClientResponse) -> bool:
+    """Check if a request was successful or not"""
+    return 200 <= response.status < 300
+
+
+@asynccontextmanager
+async def ensure_get(http_session: ClientSession, endpoint: str) -> AsyncGenerator[dict, None]:
+    """Context manager that automatically raises an exception if a GET-request fails"""
+    async with http_session.get(endpoint) as response:
+        if not request_successful(response):
+            logger.error(
+                "Failed HTTP request to %s (status %s)\nResponse: %s", endpoint, response.status, await response.json()
+            )
+
+            raise HTTPException(response.status)
+
+        yield await response.json()
+
+
+@asynccontextmanager
+async def ensure_post(
+    http_session: ClientSession, endpoint: str, payload: dict, *, expect_return: bool = True
+) -> AsyncGenerator[dict, None]:
+    """Context manager that automatically raises an exception if a POST-request fails"""
+    async with http_session.post(endpoint, data=payload) as response:
+        if not request_successful(response):
+            logger.error(
+                "Failed HTTP request to %s (status %s)\nPayload: %s\nResponse: %s",
+                endpoint,
+                response.status,
+                payload,
+                await response.json(),
+            )
+
+            raise HTTPException(response.status)
+
+        if expect_return:
+            yield await response.json()
+        else:
+            # Always return A dict so you can always "use" the result without having to check
+            # if it is None or not
+            yield {}

main.py

@@ -19,7 +19,7 @@ def setup_logging():
     max_log_size = 32 * 1024 * 1024
 
     # Configure Didier handler
-    didier_log = logging.getLogger("didier")
+    didier_log = logging.getLogger(__name__)
 
     didier_handler = RotatingFileHandler(settings.LOGFILE, mode="a", maxBytes=max_log_size, backupCount=5)
     didier_handler.setFormatter(logging.Formatter("[%(asctime)s] [%(levelname)s]: %(message)s"))