rewrite: New bot framework.

bot/meta/logger.py

@@ -0,0 +1,146 @@
+import sys
+import logging
+import asyncio
+from contextvars import ContextVar
+from discord import AllowedMentions
+
+from .config import conf
+from . import sharding
+
+
+log_context: ContextVar[str] = ContextVar('logging_context', default='CTX: ROOT CONTEXT')
+log_action: ContextVar[str] = ContextVar('logging_action', default='UNKNOWN ACTION')
+
+
+RESET_SEQ = "\033[0m"
+COLOR_SEQ = "\033[3%dm"
+BOLD_SEQ = "\033[1m"
+"]]]"
+BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = range(8)
+
+def colour_escape(fmt: str) -> str:
+    cmap = {
+        '%(black)': COLOR_SEQ % BLACK,
+        '%(red)': COLOR_SEQ % RED,
+        '%(green)': COLOR_SEQ % GREEN,
+        '%(yellow)': COLOR_SEQ % YELLOW,
+        '%(blue)': COLOR_SEQ % BLUE,
+        '%(magenta)': COLOR_SEQ % MAGENTA,
+        '%(cyan)': COLOR_SEQ % CYAN,
+        '%(white)': COLOR_SEQ % WHITE,
+        '%(reset)': RESET_SEQ,
+        '%(bold)': BOLD_SEQ,
+    }
+    for key, value in cmap.items():
+        fmt = fmt.replace(key, value)
+    return fmt
+
+
+log_format = ('[%(green)%(asctime)-19s%(reset)][%(red)%(levelname)-8s%(reset)]' +
+              '[%(cyan)SHARD {:02}%(reset)]'.format(sharding.shard_number) +
+              '[%(cyan)%(context)-22s%(reset)]' +
+              '[%(cyan)%(action)-22s%(reset)]' +
+              ' %(bold)%(cyan)%(name)s:%(reset)' +
+              ' %(white)%(message)s%(reset)')
+log_format = colour_escape(log_format)
+
+
+# Setup the logger
+logger = logging.getLogger()
+log_fmt = logging.Formatter(
+    fmt=log_format,
+    datefmt='%Y-%m-%d %H:%M:%S'
+)
+logger.setLevel(logging.NOTSET)
+
+
+class LessThanFilter(logging.Filter):
+    def __init__(self, exclusive_maximum, name=""):
+        super(LessThanFilter, self).__init__(name)
+        self.max_level = exclusive_maximum
+
+    def filter(self, record):
+        # non-zero return means we log this message
+        return 1 if record.levelno < self.max_level else 0
+
+
+class ContextInjection(logging.Filter):
+    def filter(self, record):
+        if not hasattr(record, 'context'):
+            record.context = log_context.get()
+        if not hasattr(record, 'action'):
+            record.action = log_action.get()
+        return True
+
+
+logging_handler_out = logging.StreamHandler(sys.stdout)
+logging_handler_out.setLevel(logging.DEBUG)
+logging_handler_out.setFormatter(log_fmt)
+logging_handler_out.addFilter(LessThanFilter(logging.WARNING))
+logging_handler_out.addFilter(ContextInjection())
+logger.addHandler(logging_handler_out)
+
+logging_handler_err = logging.StreamHandler(sys.stderr)
+logging_handler_err.setLevel(logging.WARNING)
+logging_handler_err.setFormatter(log_fmt)
+logging_handler_err.addFilter(ContextInjection())
+logger.addHandler(logging_handler_err)
+
+# TODO: Add an async handler for posting
+# Subclass this, create a DiscordChannelHandler, taking a Client and a channel as an argument
+# Then we can handle error channels etc differently
+# The formatting can be handled with a custom handler as well
+
+
+# Define the context log format and attach it to the command logger as well
+def log(message, context="GLOBAL", level=logging.INFO, post=True):
+    # Add prefixes to lines for better parsing capability
+    lines = message.splitlines()
+    if len(lines) > 1:
+        lines = [
+            '┌ ' * (i == 0) + '│ ' * (0 < i < len(lines) - 1) + '└ ' * (i == len(lines) - 1) + line
+            for i, line in enumerate(lines)
+        ]
+    else:
+        lines = ['─ ' + message]
+
+    for line in lines:
+        logger.log(level, '\b[{}] {}'.format(
+            str(context).center(22, '='),
+            line
+        ))
+
+    # Fire and forget to the channel logger, if it is set up
+    if post and client.is_ready():
+        asyncio.ensure_future(live_log(message, context, level))
+
+
+# Live logger that posts to the logging channels
+async def live_log(message, context, level):
+    if level >= logging.INFO:
+        if level >= logging.WARNING:
+            log_chid = conf.bot.getint('error_channel') or conf.bot.getint('log_channel')
+        else:
+            log_chid = conf.bot.getint('log_channel')
+
+        # Generate the log messages
+        if sharding.sharded:
+            header = f"[{logging.getLevelName(level)}][SHARD {sharding.shard_number}][{context}]"
+        else:
+            header = f"[{logging.getLevelName(level)}][{context}]"
+
+        if len(message) > 1900:
+            blocks = split_text(message, blocksize=1900, code=False)
+        else:
+            blocks = [message]
+
+        if len(blocks) > 1:
+            blocks = [
+                "```md\n{}[{}/{}]\n{}\n```".format(header, i+1, len(blocks), block) for i, block in enumerate(blocks)
+            ]
+        else:
+            blocks = ["```md\n{}\n{}\n```".format(header, blocks[0])]
+
+        # Post the log messages
+        if log_chid:
+            [await mail(client, log_chid, content=block, allowed_mentions=AllowedMentions.none()) for block in blocks]