python-consul · asteven · Jun 29, 2018 · Jun 29, 2018 · Jun 29, 2018 · Jun 29, 2018
diff --git a/README.rst b/README.rst
@@ -29,6 +29,19 @@ Example
     # in another process
     c.kv.put('foo', 'bar')
 
+
+Alternatively you can create a client from the same `environment variables`_ that
+the consul command line client uses. e.g. CONSUL_HTTP_ADDR, CONSUL_HTTP_TOKEN.
+
+.. code:: python
+
+    import consul
+
+    c = consul.Consul.from_env()
+
+    c.agent.self()
+
+
 Installation
 ------------
 
@@ -45,6 +58,7 @@ Installation
    image:: https://img.shields.io/coveralls/cablehead/python-consul.svg?style=flat-square
    :target: https://coveralls.io/r/cablehead/python-consul?branch=master
 .. _Read the Docs: https://python-consul.readthedocs.io/
+.. _environment variables: https://www.consul.io/docs/commands/index.html#environment-variables
 
 Status
 ------

diff --git a/consul/aio.py b/consul/aio.py
@@ -3,6 +3,8 @@
 import asyncio
 import warnings
 
+from six.moves import urllib
+
 import aiohttp
 from consul import base
 
@@ -17,8 +19,14 @@ class HTTPClient(base.HTTPClient):
     def __init__(self, *args, loop=None, **kwargs):
         super(HTTPClient, self).__init__(*args, **kwargs)
         self._loop = loop or asyncio.get_event_loop()
-        connector = aiohttp.TCPConnector(loop=self._loop,
-                                         verify_ssl=self.verify)
+        if 'unix://' in self.base_uri:
+            pr = urllib.parse.urlparse(self.base_uri)
+            self.base_uri = 'http://consul'
+            connector = aiohttp.UnixConnector(loop=self._loop,
+                                              path=pr.path)
+        else:
+            connector = aiohttp.TCPConnector(loop=self._loop,
+                                             verify_ssl=self.verify)
         self._session = aiohttp.ClientSession(connector=connector)
 
     @asyncio.coroutine
@@ -64,9 +72,9 @@ def __init__(self, *args, loop=None, **kwargs):
         self._loop = loop or asyncio.get_event_loop()
         super().__init__(*args, **kwargs)
 
-    def connect(self, host, port, scheme, verify=True, cert=None):
-        return HTTPClient(host, port, scheme, loop=self._loop,
-                          verify=verify, cert=None)
+    def connect(self, base_uri, verify=True, cert=None, auth=None):
+        return HTTPClient(base_uri, loop=self._loop,
+                          verify=verify, cert=cert, auth=auth)
 
     def close(self):
         """Close all opened http connections"""

diff --git a/consul/base.py b/consul/base.py
@@ -246,14 +246,11 @@ def cb(response):
 
 
 class HTTPClient(six.with_metaclass(abc.ABCMeta, object)):
-    def __init__(self, host='127.0.0.1', port=8500, scheme='http',
-                 verify=True, cert=None):
-        self.host = host
-        self.port = port
-        self.scheme = scheme
+    def __init__(self, base_uri, verify=True, cert=None, auth=None):
+        self.base_uri = base_uri
         self.verify = verify
-        self.base_uri = '%s://%s:%s' % (self.scheme, self.host, self.port)
         self.cert = cert
+        self.auth = auth
 
     def uri(self, path, params=None):
         uri = self.base_uri + urllib.parse.quote(path, safe='/:')
@@ -288,7 +285,9 @@ def __init__(
             consistency='default',
             dc=None,
             verify=True,
-            cert=None):
+            cert=None,
+            auth=None,
+            addr=None):
         """
         *token* is an optional `ACL token`_. If supplied it will be used by
         default for all requests made with this client session. It's still
@@ -305,27 +304,19 @@ def __init__(
 
         *verify* is whether to verify the SSL certificate for HTTPS requests
 
-        *cert* client side certificates for HTTPS requests
+        *cert* tuple containing client certificate and key for HTTPS requests
+
+        *addr* url to use instead of host, port and scheme.
+            e.g. unix:///var/run/consul/http.sock, http://localhost:8500/
         """
 
         # TODO: Status
 
-        if os.getenv('CONSUL_HTTP_ADDR'):
-            try:
-                host, port = os.getenv('CONSUL_HTTP_ADDR').split(':')
-            except ValueError:
-                raise ConsulException('CONSUL_HTTP_ADDR (%s) invalid, '
-                                      'does not match <host>:<port>'
-                                      % os.getenv('CONSUL_HTTP_ADDR'))
-        use_ssl = os.getenv('CONSUL_HTTP_SSL')
-        if use_ssl is not None:
-            scheme = 'https' if use_ssl == 'true' else 'http'
-        if os.getenv('CONSUL_HTTP_SSL_VERIFY') is not None:
-            verify = os.getenv('CONSUL_HTTP_SSL_VERIFY') == 'true'
-
-        self.http = self.connect(host, port, scheme, verify, cert)
-        self.token = os.getenv('CONSUL_HTTP_TOKEN', token)
-        self.scheme = scheme
+        if not addr:
+            addr = '{0}://{1}:{2}'.format(scheme, host, port)
+
+        self.http = self.connect(addr, verify=verify, cert=cert, auth=auth)
+        self.token = token
         self.dc = dc
         assert consistency in ('default', 'consistent', 'stale'), \
             'consistency must be either default, consistent or state'
@@ -344,6 +335,62 @@ def __init__(
         self.coordinate = Consul.Coordinate(self)
         self.operator = Consul.Operator(self)
 
+    @classmethod
+    def from_env(cls, consistency='default', dc=None):
+        """
+        Return a client configured from environment variables.
+        The environment variables used are the same as those used by the
+        consul command-line client. Refer to the consul documentation [1] for
+        a list of existing environment variables.
+
+        Additionally all supported given keyword arguments are passed on the
+        client constructor.
+
+        [1] https://www.consul.io/docs/commands/index.html#environment-variables # noqa: E501
+        """
+        oe = os.environ
+        kwargs = {
+            'consistency': consistency,
+            'dc': dc,
+            'token': oe.get('CONSUL_HTTP_TOKEN', None),
+        }
+
+        addr = oe.get('CONSUL_HTTP_ADDR', None)
+        if addr:
+            if not addr.startswith('http'):
+                # Ensure addr starts with a scheme.
+                ssl = oe.get('CONSUL_HTTP_SSL', False)
+                if ssl == 'false':
+                    ssl = False
+                elif ssl == 'true':
+                    ssl = True
+
+                if ssl:
+                    scheme = 'https'
+                else:
+                    scheme = 'http'
+                addr = '%s://%s' % (scheme, addr)
+            kwargs['addr'] = addr
+
+        verify = oe.get('CONSUL_CACERT',
+                        oe.get('CONSUL_HTTP_SSL_VERIFY', None))
+        if verify:
+            if verify == 'false':
+                verify = False
+            elif verify == 'true':
+                verify = True
+            kwargs['verify'] = verify
+
+        if 'CONSUL_CLIENT_CERT' in oe \
+                and 'CONSUL_CLIENT_KEY' in oe:
+            kwargs['cert'] = (oe['CONSUL_CLIENT_CERT'],
+                              oe['CONSUL_CLIENT_KEY'])
+
+        if 'CONSUL_HTTP_AUTH' in oe:
+            kwargs['auth'] = oe['CONSUL_HTTP_AUTH'].split(':')
+
+        return cls(**kwargs)
+
     class Event(object):
         """
         The event command provides a mechanism to fire a custom user event to

diff --git a/consul/std.py b/consul/std.py
@@ -1,5 +1,7 @@
 import requests
 
+from six.moves import urllib
+
 from consul import base
 
 
@@ -9,7 +11,19 @@
 class HTTPClient(base.HTTPClient):
     def __init__(self, *args, **kwargs):
         super(HTTPClient, self).__init__(*args, **kwargs)
-        self.session = requests.session()
+        if 'unix://' in self.base_uri:
+            pr = urllib.parse.urlparse(self.base_uri)
+            netloc = urllib.parse.quote_plus(pr.path)
+            self.base_uri = 'http+unix://{0}'.format(netloc)
+            try:
+                import requests_unixsocket
+                self.session = requests_unixsocket.Session()
+            except ImportError:
+                raise base.ConsulException('To use a unix socket to connect to'
+                                           ' Consul you need to install the'
+                                           ' "requests_unixsocket" package.')
+        else:
+            self.session = requests.session()
 
     def response(self, response):
         response.encoding = 'utf-8'
@@ -40,5 +54,5 @@ def post(self, callback, path, params=None, data=''):
 
 
 class Consul(base.Consul):
-    def connect(self, host, port, scheme, verify=True, cert=None):
-        return HTTPClient(host, port, scheme, verify, cert)
+    def connect(self, base_uri, verify=True, cert=None, auth=None):
+        return HTTPClient(base_uri, verify=verify, cert=cert, auth=auth)
diff --git a/consul/tornado.py b/consul/tornado.py
@@ -12,6 +12,7 @@
 class HTTPClient(base.HTTPClient):
     def __init__(self, *args, **kwargs):
         super(HTTPClient, self).__init__(*args, **kwargs)
+        # TODO: support for unix:// uris
         self.client = httpclient.AsyncHTTPClient()
 
     def response(self, response):
@@ -53,5 +54,5 @@ def post(self, callback, path, params=None, data=''):
 
 
 class Consul(base.Consul):
-    def connect(self, host, port, scheme, verify=True, cert=None):
-        return HTTPClient(host, port, scheme, verify=verify, cert=cert)
+    def connect(self, base_uri, verify=True, cert=None, auth=None):
+        return HTTPClient(base_uri, verify=verify, cert=cert, auth=auth)
diff --git a/consul/twisted.py b/consul/twisted.py
@@ -34,6 +34,7 @@ def getContext(self, hostname, port):
 class HTTPClient(base.HTTPClient):
     def __init__(self, contextFactory, *args, **kwargs):
         super(HTTPClient, self).__init__(*args, **kwargs)
+        # TODO: support for unix:// uris
         agent_kwargs = dict(
             reactor=reactor, pool=HTTPConnectionPool(reactor))
         if contextFactory is not None:
@@ -125,13 +126,12 @@ def delete(self, callback, path, params=None):
 
 class Consul(base.Consul):
     @staticmethod
-    def connect(host,
-                port,
-                scheme,
+    def connect(base_uri,
                 verify=True,
                 cert=None,
+                auth=None,
                 contextFactory=None,
                 **kwargs):
         return HTTPClient(
-            contextFactory, host, port, scheme, verify=verify, cert=cert,
+            contextFactory, base_uri, verify=verify, cert=cert, auth=auth,
             **kwargs)
diff --git a/requirements.txt b/requirements.txt
@@ -1,2 +1,3 @@
 requests>=2.0
+requests-unixsocket>=0.1.5
 six>=1.4