Adds DC/OS lib

Eliminates our dependency on the DC/OS lib until the day that dcos/dcos-cli#823 gets merged and we have a new lib.

Author: huntc

README.rst

@@ -177,6 +177,9 @@ For pointers on command usage run ``shazar -h``.
 Developers
 ~~~~~~~~~~
 
+> Note that we presently package the dcos library as source. When https://github.com/dcos/dcos-cli/pull/823 becomes available then
+we should remove this directory and depend on it directly.
+
 For OS X, you should ensure firstly that you have the latest Xcode command line tools installed.
 
 Now install the latest python3 version on your system, on OS X use:

conductr_cli/conduct_main.py

@@ -284,15 +284,20 @@ def build_parser(dcos_mode):
 def get_cli_parameters(args):
     parameters = ['']
     if not args.dcos_mode:
-        if vars(args).get('scheme') != DEFAULT_SCHEME:
+        arg = vars(args).get('scheme')
+        if arg and arg != DEFAULT_SCHEME:
             parameters.append('--scheme {}'.format(args.scheme))
-        if vars(args).get('ip') != host.resolve_default_ip():
+        arg = vars(args).get('ip')
+        if arg and arg != host.resolve_default_ip():
             parameters.append('--ip {}'.format(args.ip))
-        if vars(args).get('port', int(DEFAULT_PORT)) != int(DEFAULT_PORT):
+        arg = vars(args).get('port', int(DEFAULT_PORT))
+        if arg and arg != int(DEFAULT_PORT):
             parameters.append('--port {}'.format(args.port))
-        if vars(args).get('base_path', DEFAULT_BASE_PATH) != DEFAULT_BASE_PATH:
+        arg = vars(args).get('base_path', DEFAULT_BASE_PATH)
+        if arg and arg != DEFAULT_BASE_PATH:
             parameters.append('--base-path {}'.format(args.base_path))
-    if vars(args).get('api_version', DEFAULT_API_VERSION) != DEFAULT_API_VERSION:
+    arg = vars(args).get('api_version', DEFAULT_API_VERSION)
+    if arg and arg != DEFAULT_API_VERSION:
         parameters.append('--api-version {}'.format(args.api_version))
     return ' '.join(parameters)
 

dcos/__init__.py

@@ -0,0 +1,4 @@
+# Version is set for releases by our build system.
+# Be extremely careful when modifying.
+version = 'SNAPSHOT'
+"""DC/OS version"""

dcos/cmds.py

@@ -0,0 +1,45 @@
+import collections
+
+from dcos.errors import DCOSException
+
+Command = collections.namedtuple(
+    'Command',
+    ['hierarchy', 'arg_keys', 'function'])
+"""Describe a CLI command.
+
+:param hierarchy: the noun and verbs that need to be set for the command to
+                  execute
+:type hierarchy: list of str
+:param arg_keys: the arguments that must get passed to the function; the order
+                 of the keys determines the order in which they get passed to
+                 the function
+:type arg_keys: list of str
+:param function: the function to execute
+:type function: func(args) -> int
+"""
+
+
+def execute(cmds, args):
+    """Executes one of the commands based on the arguments passed.
+
+    :param cmds: commands to try to execute; the order determines the order of
+                 evaluation
+    :type cmds: list of Command
+    :param args: command line arguments
+    :type args: dict
+    :returns: the process status
+    :rtype: int
+    """
+
+    for hierarchy, arg_keys, function in cmds:
+        # Let's find if the function matches the command
+        match = True
+        for positional in hierarchy:
+            if not args[positional]:
+                match = False
+
+        if match:
+            params = [args[name] for name in arg_keys]
+            return function(*params)
+
+    raise DCOSException('Could not find a command with the passed arguments')