Consulate: A Consul Client Library

Consulate is a Python client library and set of application for the Consul service discovery and configuration system.

Installation

Consulate is available via via pypi and can be installed with easy_install or pip:

pip install consulate

If you require communicating with Consul via a Unix socket, there is an extra dependency that is installed via:

pip install consulate[unixsocket]

Command Line Utilities

Consulate comes with two command line utilities that make working with Consul easier from a management perspective. The consulate application provides a cli wrapper for common tasks performed.

consulate

The consulate application provides a CLI interface for registering a service, backing up and restoring the contents of the KV database, and actions for getting, setting, and deleting keys from the KV database.

usage: consulate [-h] [--api-scheme API_SCHEME] [--api-host API_HOST]
                 [--api-port API_PORT] [--datacenter DC] [--token TOKEN]
                 {register,deregister,kv,run_once} ...

CLI utilities for Consul

optional arguments:
  -h, --help            show this help message and exit
  --api-scheme API_SCHEME
                        The scheme to use for connecting to Consul with
  --api-host API_HOST   The consul host to connect on
  --api-port API_PORT   The consul API port to connect to
  --datacenter DC       The datacenter to specify for the connection
  --token TOKEN         ACL token

Commands:
  {register,deregister,kv,run_once,services}
    register            Register a service for this node
    deregister          Deregister a service for this node
    kv                  Key/Value Database Utilities
    run_once            Lock command
    services            List services for this node

If the CONSUL_RPC_ADDR environment variable is set, it will be parsed and used
for default values when connecting.

Service Registration Help:

usage: consulate register [-h] [-a ADDRESS] [-p PORT] [-s SERVICE_ID]
                          [-t TAGS]
                          name {check,httpcheck,no-check,ttl} ...

positional arguments:
  name                  The service name

optional arguments:
  -h, --help            show this help message and exit
  -a ADDRESS, --address ADDRESS
                        Specify an address
  -p PORT, --port PORT  Specify a port
  -s SERVICE_ID, --service-id SERVICE_ID
                        Specify a service ID
  -t TAGS, --tags TAGS  Specify a comma delimited list of tags

Service Check Options:
  {check,httpcheck,no-check,ttl}
    check               Define an external script-based check
    httpcheck           Define an HTTP-based check
    no-check            Do not enable service monitoring
    ttl                 Define a duration based TTL check

KV Database Utilities Help:

usage: consulate kv [-h] {backup,restore,ls,mkdir,get,set,rm} ...

optional arguments:
  -h, --help            show this help message and exit

Key/Value Database Utilities:
  {backup,restore,ls,mkdir,get,set,rm}
    backup              Backup to stdout or a JSON file
    restore             Restore from stdin or a JSON file
    ls                  List all of the keys
    mkdir               Create a folder
    get                 Get a key from the database
    set                 Set a key in the database
    rm                  Remove a key from the database

Locking Operations Help:

usage: consulate [-h] run_once [-i INTERVAL] prefix command

positional arguments:
  prefix                the name of the lock which will be held in Consul.
  command               the command to run

optional arguments:
  -h, --help            show this help message and exit
  -i, --interval        hold the lock for INTERVAL seconds

Service listing Help:

usage: consulate services [-h] [-i INDENT]

optional arguments:
  -h, --help            show this help message and exit
  -i INDENT, --indent INDENT
                        The indent level for output

API Usage Examples

The following examples highlight the usage of Consulate and does not document the scope of the full Consulate API.

Using Consulate with the Consul kv database:

consul = consulate.Consul()

# Set the key named release_flag to True
consul.kv['release_flag'] = True

# Get the value for the release_flag, if not set, raises AttributeError
try:
    should_release_feature = consul.kv['release_flag']
except AttributeError:
    should_release_feature = False

# Delete the release_flag key
del consul.kv['release_flag']

# Find all keys that start with "fl"
consul.kv.find('fl')

# Find all keys that start with "feature_flag" terminated by "/" separator
consul.kv.find('feature_flag', separator='/')

# Check to see if a key called "foo" is set
if "foo" in consul.kv:
    print 'Already Set'

# Return all of the items in the key/value store
consul.kv.items()

Working with the Consulate.agent API:

consul = consulate.Consul()

# Get all of the service checks for the local agent
checks = consul.agent.checks()

# Get all of the services registered with the local agent
services = consul.agent.services()

# Add a service to the local agent
consul.agent.service.register('redis',
                               port=6379,
                               tags=['master'],
                               ttl='10s')

Fetching health information from Consul:

consul = consulate.Consul()

# Get the health of a individual node
health = consul.health.node('my-node')

# Get all checks that are critical
checks = consul.heath.state('critical')

For more examples, check out the Consulate documentation.