Resolve lack of logging.

Author: toddbirchard

.flake8

@@ -0,0 +1,4 @@
+[flake8]
+select = E9,F63,F7,F82
+exclude = .git,.github,__pycache__,.pytest_cache,.venv,logs,creds
+max-line-length = 120

config.py

@@ -1,4 +1,5 @@
 """Flask configuration variables."""
+
 from os import environ, path
 
 from dotenv import load_dotenv
@@ -11,6 +12,7 @@ class Config:
     """Set Flask configuration from .env file."""
 
     # General Config
+    APPLICATION_NAME = "flaskassets"
     ENVIRONMENT = environ.get("ENVIRONMENT")
 
     # Flask Config
@@ -27,3 +29,6 @@ class Config:
     STATIC_FOLDER = "static"
     TEMPLATES_FOLDER = "templates"
     COMPRESSOR_DEBUG = True
+
+
+settings = Config()

flask_assets_tutorial/__init__.py

@@ -1,4 +1,5 @@
 """Initialize Flask app."""
+
 from flask import Flask
 from flask_assets import Environment
 

flask_assets_tutorial/admin/routes.py

@@ -1,12 +1,15 @@
 """Routes for logged-in account pages."""
+
 from flask import Blueprint, render_template
+from log import LOGGER
 
 admin_blueprint = Blueprint("admin_blueprint", __name__, template_folder="templates", static_folder="static")
 
 
 @admin_blueprint.route("/dashboard", methods=["GET"])
 def dashboard():
     """Admin dashboard route."""
+    LOGGER.info("Admin dashboard rendered by user.")
     return render_template(
         "dashboard.jinja2",
         title="Admin Dashboard",

flask_assets_tutorial/assets.py

@@ -1,4 +1,5 @@
 """Compile static assets."""
+
 from flask import current_app as app
 from flask_assets import Bundle, Environment
 

flask_assets_tutorial/main/routes.py

@@ -1,12 +1,15 @@
 """Routes for main pages."""
+
 from flask import Blueprint, render_template
+from log import LOGGER
 
 main_blueprint = Blueprint("main_blueprint", __name__, template_folder="templates", static_folder="static")
 
 
 @main_blueprint.route("/", methods=["GET"])
 def home():
     """Home page route."""
+    LOGGER.info("Home page rendered by user.")
     return render_template(
         "index.jinja2",
         title="Home",
@@ -19,6 +22,7 @@ def home():
 @main_blueprint.route("/about", methods=["GET"])
 def about():
     """About page route."""
+    LOGGER.info("About page rendered by user.")
     return render_template(
         "index.jinja2",
         title="About",
@@ -31,6 +35,7 @@ def about():
 @main_blueprint.route("/etc", methods=["GET"])
 def etc():
     """Etc page route."""
+    LOGGER.info("Etc. page rendered by user.")
     return render_template(
         "index.jinja2",
         title="Etc.",

gunicorn.conf.py

@@ -1,4 +1,5 @@
 """Gunicorn configuration file."""
+
 import socket
 from os import environ, path
 
@@ -23,7 +24,7 @@
 
 if ENVIRONMENT == "production":
     daemon = True
-    accesslog = "/var/log/flaskassets/access.log"
+    accesslog = "/var/log/flaskassets/info.log"
     errorlog = "/var/log/flaskassets/error.log"
     loglevel = "trace"
-    dogstatsd_tags = "env:prod,service:flaskassets,language:python"
+    dogstatsd_tags = "env:prod,service:flaskassets,language:python,type:tutorial"

log.py

@@ -0,0 +1,122 @@
+"""Custom logger."""
+
+import json
+from sys import stdout
+
+from loguru import logger
+
+from config import settings
+
+
+def json_formatter(record: dict) -> str:
+    """
+    Pass raw log to be serialized.
+
+    :param dict record: Dictionary containing logged message with metadata.
+
+    :returns: str
+    """
+
+    def serialize(log: dict) -> str:
+        """
+        Parse log message into Datadog JSON format.
+
+        :param dict log: Dictionary containing logged message with metadata.
+
+        :returns: str
+        """
+        subset = {
+            "time": log["time"].strftime("%m/%d/%Y, %H:%M:%S"),
+            "message": log["message"],
+            "level": log["level"].name,
+            "function": log.get("function"),
+            "module": log.get("name"),
+        }
+        if log.get("exception", None):
+            subset.update({"exception": log["exception"]})
+        return json.dumps(subset)
+
+    record["extra"]["serialized"] = serialize(record)
+    return "{extra[serialized]},\n"
+
+
+def log_formatter(record: dict) -> str:
+    """
+    Formatter for .log records
+
+    :param dict record: Key/value object containing log message & metadata.
+
+    :returns: str
+    """
+    if record["level"].name == "TRACE":
+        return "<fg #5278a3>{time:MM-DD-YYYY HH:mm:ss}</fg #5278a3> | <fg #d2eaff>{level}</fg #d2eaff>: <light-white>{message}</light-white>\n"
+    if record["level"].name == "INFO":
+        return "<fg #5278a3>{time:MM-DD-YYYY HH:mm:ss}</fg #5278a3> | <fg #98bedf>{level}</fg #98bedf>: <light-white>{message}</light-white>\n"
+    if record["level"].name == "WARNING":
+        return "<fg #5278a3>{time:MM-DD-YYYY HH:mm:ss}</fg #5278a3> |  <fg #b09057>{level}</fg #b09057>: <light-white>{message}</light-white>\n"
+    if record["level"].name == "SUCCESS":
+        return "<fg #5278a3>{time:MM-DD-YYYY HH:mm:ss}</fg #5278a3> | <fg #6dac77>{level}</fg #6dac77>: <light-white>{message}</light-white>\n"
+    if record["level"].name == "ERROR":
+        return "<fg #5278a3>{time:MM-DD-YYYY HH:mm:ss}</fg #5278a3> | <fg #a35252>{level}</fg #a35252>: <light-white>{message}</light-white>\n"
+    if record["level"].name == "CRITICAL":
+        return "<fg #5278a3>{time:MM-DD-YYYY HH:mm:ss}</fg #5278a3> | <fg #521010>{level}</fg #521010>: <light-white>{message}</light-white>\n"
+    return "<fg #5278a3>{time:MM-DD-YYYY HH:mm:ss}</fg #5278a3> | <fg #98bedf>{level}</fg #98bedf>: <light-white>{message}</light-white>\n"
+
+
+def create_logger() -> logger:
+    """
+    Configure custom logger.
+
+    :returns: logger
+    """
+    logger.remove()
+    logger.add(
+        stdout,
+        colorize=True,
+        catch=True,
+        level="TRACE",
+        format=log_formatter,
+    )
+    if settings.ENVIRONMENT == "production":
+        # Datadog JSON logs
+        logger.add(
+            f"/var/log/{settings.APPLICATION_NAME}/info.json",
+            format=json_formatter,
+            rotation="200 MB",
+            level="TRACE",
+            compression="zip",
+        )
+        # Readable logs
+        logger.add(
+            f"/var/log/{settings.APPLICATION_NAME}/info.log",
+            colorize=True,
+            catch=True,
+            level="TRACE",
+            format=log_formatter,
+            rotation="200 MB",
+            compression="zip",
+        )
+    else:
+        logger.add(
+            "./logs/info.log",
+            colorize=True,
+            catch=True,
+            format=log_formatter,
+            rotation="200 MB",
+            compression="zip",
+            level="INFO",
+        )
+        logger.add(
+            "./logs/error.log",
+            colorize=True,
+            catch=True,
+            format=log_formatter,
+            rotation="200 MB",
+            compression="zip",
+            level="ERROR",
+        )
+    return logger
+
+
+# Custom logger
+LOGGER = create_logger()