Initial code check-in

This commit is contained in:
Scott Wallace 2020-10-10 14:11:43 +01:00
commit 12d09852da
4 changed files with 180 additions and 0 deletions

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.dockerignore Normal file
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**/__pycache__
**/.classpath
**/.dockerignore
**/.env
**/.git
**/.gitignore
**/.project
**/.settings
**/.toolstarget
**/.vs
**/.vscode
**/*.*proj.user
**/*.dbmdl
**/*.jfm
**/azds.yaml
**/bin
**/charts
**/docker-compose*
**/Dockerfile*
**/node_modules
**/npm-debug.log
**/obj
**/secrets.dev.yaml
**/values.dev.yaml
README.md

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Dockerfile Normal file
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# For more information, please refer to https://aka.ms/vscode-docker-python
FROM python:3.8-slim-buster
# Keeps Python from generating .pyc files in the container
ENV PYTHONDONTWRITEBYTECODE 1
# Turns off buffering for easier container logging
ENV PYTHONUNBUFFERED 1
# Install pip requirements
ADD requirements.txt .
RUN python -m pip install -r requirements.txt
WORKDIR /app
ADD . /app
# Switching to a non-root user, please refer to https://aka.ms/vscode-docker-python-user-rights
# RUN useradd appuser && chown -R appuser /app
# USER appuser
EXPOSE 8080
# During debugging, this entry point will be overridden. For more information, please refer to https://aka.ms/vscode-docker-python-debug
CMD ["python", "dockstat.py"]
HEALTHCHECK --interval=30s --timeout=3s --retries=1 \
CMD python3 /app/dockstat.py --healthcheck

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dockstat.py Normal file
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#!/usr/bin/env python3
"""
Module to act as a Prometheus Exporter for Docker containers with a
healthcheck configured
"""
import argparse
import http.server
import os.path
import socketserver
import sys
import time
import docker
LISTEN_PORT = 8080
HEALTHY_STR = 'healthy'
class SimpleHTTPRequestHandler(http.server.BaseHTTPRequestHandler):
"""
Class to encompass the requirements of a Prometheus Exporter
for Docker containers with a healthcheck configured
"""
# pylint: disable=invalid-name
def do_GET(self):
"""
Method to handle GET requests
"""
if self.path == '/metrics':
self._metrics()
if self.path == '/healthcheck':
self._healthcheck()
def _healthcheck(self, message=True):
"""
Method to return 200 or 500 response and an optional message
"""
if not healthy():
self.send_response(500)
self.end_headers()
if message:
self.wfile.write(b'ERR')
return
self.send_response(200)
self.end_headers()
if message:
self.wfile.write(b'OK')
def _metrics(self):
"""
Method to handle the request for metrics
"""
self._healthcheck(message=False)
api = docker.APIClient()
client = docker.from_env()
for container in client.containers.list():
now = int(round(time.time() * 1000))
data = api.inspect_container(container.id)
try:
health_str = data["State"]["Health"]["Status"]
except KeyError:
pass
else:
self.wfile.write(
bytes(
f'container_inspect_state_health_status{{'
f'id="{container.id}",'
f'name="{container.name}",'
f'value="{health_str}"'
f'}} '
f'{int(health_str == HEALTHY_STR)} {now}\n'.encode()
)
)
def healthy():
"""
Simple funtion to return if all the requirements are met
"""
return all([
os.path.exists('/var/run/docker.sock'),
])
if __name__ == '__main__':
def cli_parse():
"""
Function to parse the CLI
"""
parser = argparse.ArgumentParser()
parser.add_argument(
'-H', '--healthcheck',
action='store_true',
help='Simply exit with 0 for healthy or 1 when unhealthy',
)
return parser.parse_args()
def main():
"""
main()
"""
args = cli_parse()
if args.healthcheck:
# Invert the sense of 'healthy' for Unix CLI usage
return not healthy()
Handler = SimpleHTTPRequestHandler
with socketserver.TCPServer(('', LISTEN_PORT), Handler) as httpd:
httpd.serve_forever()
return True
sys.exit(main())

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# To ensure app dependencies are ported from your virtual environment/host machine into your container, run 'pip freeze > requirements.txt' in the terminal to overwrite this file
docker