conn-check 1.0.9

Utility/library for checking connectivity between services

conn-check allows for checking connectivity with external services.

You can write a config file that defines services that you need to have access to, and conn-check will check connectivity with each.

It supports various types of services, all of which allow for basic network checks, but some allow for confirming credentials work also.

Configuration

The configuration is done via a yaml file. The file defines a list of checks to do:

- type: tcp
  host: localhost
  port: 80
- type: ssl
  host: localhost
  port: 443
  verify: true

Each check defines a type, and then options as appropriate for that type.

Check Types

tcp

A simple tcp connectivity check.

host

The host.

port

The port.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

ssl

A check that uses SSL.

host

The host.

port

The port.

verify

Optional flag whether to also verify the SSL certificate. Default: true.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

udp

Check that sending a specific UDP packet gets a specific response.

host

The host.

port

The port.

send

The string to send.

expect

The string to expect in the response.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

http

Check that a HTTP/HTTPS request succeeds.

url

The URL to fetch.

method

Optional HTTP method to use. Default: “GET”.

expected_code

Optional status code that defines success. Default: 200.

proxy_host

Optional HTTP/HTTPS proxy to connect via.

proxy_port

Optional port to use with proxy_host. Default: 8000.

headers:

Optional headers to send, as a dict of key-values. Multiple values can be given as a list under the same key.

body:

Optional raw request body string to send.

disable_tls_verification:

Optional flag to disable verification of TLS certs and handshake. Default: false.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

amqp

Check that an AMQP server can be authenticated against.

host

The host.

port

The port.

username

The username to authenticate with.

password

The password to authenticate with.

use_ssl

Optional flag whether to connect with ssl. Default: true.

vhost

Optional vhost name to connect to. Default ‘/’.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

postgres

Check that a postgres db can be authenticated against.

host

The host.

port

The port.

username

The username to authenticate with.

password

The password to authenticate with.

database

The database to connect to.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

redis

Check that a redis server is present, optionally checking authentication.

host

The host.

port

The port.

password

Optional password to authenticatie with.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

memcached

Check that a memcached server is present (memcache also works).

host

The host.

port

The port.

timeout

Optional connection timeout in seconds. Default: 10 (or value from --connect-timeout).

Building wheels

To allow for easier/more portable distribution of this tool you can build conn-check and all it’s dependencies as Python wheels:

make clean-wheels
make build-wheels
make build-wheels-extra EXTRA=amqp
make build-wheels-extra EXTRA=redis

The build-wheels make target will build conn-check and it’s base dependencies, but to include the optional extra dependencies for other checks such as amqp, redis or postgres you need to use the build-wheels-extra target with the EXTRA env value.

By default all the wheels will be placed in ./wheels.

Automatically generating conn-check YAML configurations

The conn-check-configs package contains utilities/libraries for generating checks from existing application configurations and environments, e.g. from Django settings modules and Juju environments.