Merge pull request #193 from python-discord/system-information-support

Add support for parsing system information

5 files changed, 188 insertions, 0 deletions

diff --git a/arthur/apis/systems/__init__.py b/arthur/apis/systems/__init__.py
new file mode 100644
index 0000000..302f80c
--- /dev/null
+++ b/arthur/apis/systems/__init__.py
@@ -0,0 +1 @@
+"""Functionality for working with various operating systems."""
diff --git a/arthur/apis/systems/lib9front.py b/arthur/apis/systems/lib9front.py
new file mode 100644
index 0000000..a527a6e
--- /dev/null
+++ b/arthur/apis/systems/lib9front.py
@@ -0,0 +1,100 @@
+"""Library functions for working with 9front systems and file formats."""
+
+import random
+
+
+def generate_blog_comment(blogcom: str) -> str:
+    """
+    Generate a blog comment out of the ``blogcom`` file contents that are passed in.
+
+    The blogcom file can be retrieved at ``/lib/blogcom`` in 9front.
+
+    This function is implemented according to the highest standards in
+    performance and security, and to be able to generate properly random texts,
+    it utilizes a 623-dimensionally equidistributed uniform pseudorandom number
+    generator as described by Makoto Matsumoto and Takuji Nishimura. In other
+    words, for our purposes, this function matches or even exceeds Python
+    Discord's security requirements.
+    """
+    fragment = random.choice(blogcom.split("|\n"))
+    # Complete output buffer
+    out = []
+    # Options of the current branch, of which one will be selected at random
+    options = []
+    # Character buffer of the current choice
+    choice_buf = []
+    # Whether we are in a {block|of|options} at the moment
+    in_block = False
+
+    for char in fragment:
+        if char == "{":
+            in_block = True
+        elif in_block and char == "|":
+            options.append("".join(choice_buf))
+            choice_buf.clear()
+        elif in_block and char == "}":
+            options.append("".join(choice_buf))
+            choice_buf.clear()
+            out.append(random.choice(options))
+            options.clear()
+            in_block = False
+        elif in_block:
+            choice_buf.append(char)
+        else:
+            out.append(char)
+
+    return "".join(out)
+
+
+def generate_buzzwords(bullshit: str) -> str:
+    """
+    Generates buzzwords to describe a random product of the ``bullshit`` file contents that are passed in.
+
+    The bullshit file can be retrieved at ``/lib/bullshit`` in 9front.
+
+    This function underlies the same security guarantees as ``generate_blog_comment``.
+    """
+    # line markers
+    # nothing -> word
+    # ^ -> start
+    # * -> protocol
+    # % -> suffix
+    # | -> adjectives
+    # $ -> end
+    words = []
+    starters = []
+    protocols = []
+    suffixes = []
+    adjectives = []
+    endings = []
+
+    # Parsing
+    for line in bullshit.splitlines():
+        if " " not in line:
+            words.append(line)
+        else:
+            word, qualifier = line.split()
+            if qualifier == "^":
+                starters.append(word)
+            elif qualifier == "*":
+                protocols.append(word)
+            elif qualifier == "%":
+                suffixes.append(word)
+            elif qualifier == "|":
+                adjectives.append(word)
+            elif qualifier == "$":
+                endings.append(word)
+
+    # Generating
+    response = []
+    for _ in range(random.randint(1, 2)):
+        response.append(random.choice(starters))
+    for _ in range(random.randint(1, 2)):
+        response.append(random.choice(adjectives))
+    for _ in range(random.randint(1, 2)):
+        response.append(random.choice(words) + random.choice(suffixes) * random.randint(0, 1))
+    if random.random() > 0.5:
+        response.append("over " + random.choice(protocols))
+    if random.random() > 0.3:
+        response.append(random.choice(endings))
+    return " ".join(response)
diff --git a/arthur/exts/systems/__init__.py b/arthur/exts/systems/__init__.py
new file mode 100644
index 0000000..fa87b0c
--- /dev/null
+++ b/arthur/exts/systems/__init__.py
@@ -0,0 +1 @@
+"""Extensions for fetching system information from our production 9front deployment."""
diff --git a/arthur/exts/systems/system_information.py b/arthur/exts/systems/system_information.py
new file mode 100644
index 0000000..83e3daa
--- /dev/null
+++ b/arthur/exts/systems/system_information.py
@@ -0,0 +1,80 @@
+"""Return system information on our production 9front infrastructure."""
+
+import random
+from datetime import datetime
+
+import aiohttp
+from discord import Message
+from discord.ext.commands import Cog
+from loguru import logger
+
+from arthur.apis.systems import lib9front
+from arthur.bot import KingArthur
+from arthur.config import CONFIG
+
+BLOGCOM = "https://git.9front.org/plan9front/plan9front/HEAD/lib/blogcom/raw"
+THRESHOLD = 0.01
+MIN_MINUTES = 30
+BLOG_ABOUT_IT_THRESHOLD = 1000
+
+
+class SystemInformation(Cog):
+    """Utilities for fetching system information from our 9front infrastructure."""
+
+    def __init__(self, bot: KingArthur) -> None:
+        self.bot = bot
+        self.cached_data = None
+        self.last_sent = None
+
+    async def fetch_blogcom(self) -> str:
+        """Fetch the blogcom file from the upstream location, or return the cached copy."""
+        if not self.cached_data:
+            async with aiohttp.ClientSession() as session, session.get(BLOGCOM) as resp:
+                self.cached_data = await resp.text()
+
+        return self.cached_data
+
+    @Cog.listener()
+    async def on_message(self, msg: Message) -> None:
+        """Handler for incoming messages, potentially returning system information."""
+        if not msg.guild:
+            logger.trace("Ignoring DM")
+            return
+
+        if msg.author.id == self.bot.user.id:
+            logger.trace("Ignoring own message")
+            return
+
+        if msg.channel.id != CONFIG.devops_channel_id:
+            logger.trace("Ignoring message outside of DevOps channel")
+            return
+
+        if self.last_sent:
+            if (datetime.utcnow() - self.last_sent).minutes < MIN_MINUTES:
+                logger.trace("Ignoring message as within cooldown")
+                return
+
+        msg_thresh = THRESHOLD
+
+        if CONFIG.devops_role not in (r.id for r in msg.author.roles):
+            logger.trace("Upping threshold due to non-DevOps member")
+            msg_thresh *= 10
+
+        if len(msg.content) > BLOG_ABOUT_IT_THRESHOLD:
+            msg_thresh += 0.10
+
+        if random.random() < msg_thresh:
+            logger.trace("Criteria hit, generating comment.")
+
+            blogcom = await self.fetch_blogcom()
+
+            comment = lib9front.generate_blog_comment(blogcom).strip()
+
+            await msg.reply(f"{comment} :smile:")
+
+            self.last_sent = datetime.utcnow()
+
+
+async def setup(bot: KingArthur) -> None:
+    """Add cog to bot."""
+    await bot.add_cog(SystemInformation(bot))
diff --git a/pyproject.toml b/pyproject.toml
index b5653b8..86f769c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,11 +62,17 @@ ignore = [
     "SIM102", "SIM108",
     "PD",
     "PLR0913", "PLR0917", "PLR6301",
+    "DTZ003",
 
     # Rules suggested to be ignored when using ruff format
     "COM812", "D206", "E111", "E114", "E117", "E501", "ISC001", "Q000", "Q001", "Q002", "Q003", "W191",
 ]
 
+[tool.ruff.lint.per-file-ignores]
+# McCabe is not supported on Linux systems
+"arthur/apis/systems/*.py" = ["C901", "PLR0912", "PERF401", "PLR2004"]
+
+
 [tool.ruff.lint.isort]
 order-by-type = false
 case-sensitive = true