modularization of inventory_import command

This separates file parsing logic that was mixed
in with other important code inside of the
inventory import command.

The logic around MemObject data structures was
moved to utils, and the file parsing was moved
to a legacy module. As of this commit, that
module can operate within the Tower environment
but it will be removed.

Also refactor the loggers to fix old bug and
work inside of the different contexts - the
Loader classes, mem objects, and hopefully
the inventory modules eventually.

awx/main/tests/unit/utils/test_mem_inventory.py

@@ -0,0 +1,128 @@
+# AWX utils
+from awx.main.utils.mem_inventory import (
+    MemInventory,
+    mem_data_to_dict, dict_to_mem_data
+)
+
+import pytest
+import json
+
+
+@pytest.fixture
+def memory_inventory():
+    inventory = MemInventory()
+    h = inventory.get_host('my_host')
+    h.variables = {'foo': 'bar'}
+    g = inventory.get_group('my_group')
+    g.variables = {'foobar': 'barfoo'}
+    h2 = inventory.get_host('group_host')
+    g.add_host(h2)
+    return inventory
+
+
+@pytest.fixture
+def JSON_of_inv():
+    # Implemented as fixture becuase it may be change inside of tests
+    return {
+        "_meta": {
+            "hostvars": {
+                "group_host": {},
+                "my_host": {"foo": "bar"}
+            }
+        }, 
+        "all": {"children": ["my_group",  "ungrouped"]},
+        "my_group": {
+            "hosts": ["group_host"],
+            "vars": {"foobar": "barfoo"}
+        },
+        "ungrouped": {"hosts": ["my_host"]}
+    }
+
+
+# Structure mentioned in official docs
+# https://docs.ansible.com/ansible/dev_guide/developing_inventory.html
+@pytest.fixture
+def JSON_with_lists():
+    docs_example = '''{
+       "databases"   : {
+           "hosts"   : [ "host1.example.com", "host2.example.com" ],
+           "vars"    : {
+               "a"   : true
+           }
+       },
+       "webservers"  : [ "host2.example.com", "host3.example.com" ],
+       "atlanta"     : {
+           "hosts"   : [ "host1.example.com", "host4.example.com", "host5.example.com" ],
+           "vars"    : {
+               "b"   : false
+           },
+           "children": [ "marietta", "5points" ]
+       },
+       "marietta"    : [ "host6.example.com" ],
+       "5points"     : [ "host7.example.com" ]
+    }'''
+    return json.loads(docs_example)
+
+
+# MemObject basic operations tests
+
+@pytest.mark.inventory_import
+def test_inventory_create_all_group():
+    inventory = MemInventory()
+    assert inventory.all_group.name == 'all'
+
+
+@pytest.mark.inventory_import
+def test_create_child_group():
+    inventory = MemInventory()
+    g1 = inventory.get_group('g1')
+    # Create new group by name as child of g1
+    g2 = inventory.get_group('g2', g1)
+    # Check that child is in the children of the parent group
+    assert g1.children == [g2]
+    # Check that _only_ the parent group is listed as a root group
+    assert inventory.all_group.children == [g1]
+    # Check that _both_ are tracked by the global `all_groups` dict
+    assert set(inventory.all_group.all_groups.values()) == set([g1, g2])
+
+
+@pytest.mark.inventory_import
+def test_ungrouped_mechanics():
+    # ansible-inventory returns a group called `ungrouped`
+    # we can safely treat this the same as the `all_group`
+    inventory = MemInventory()
+    ug = inventory.get_group('ungrouped')
+    assert ug is inventory.all_group
+
+
+# MemObject --> JSON tests
+
+@pytest.mark.inventory_import
+def test_convert_memory_to_JSON_with_vars(memory_inventory):
+    data = mem_data_to_dict(memory_inventory)
+    # Assertions about the variables on the objects
+    assert data['_meta']['hostvars']['my_host'] == {'foo': 'bar'}
+    assert data['my_group']['vars'] == {'foobar': 'barfoo'}
+    # Orphan host should be found in ungrouped false group
+    assert data['ungrouped']['hosts'] == ['my_host']
+
+
+# JSON --> MemObject tests
+
+@pytest.mark.inventory_import
+def test_convert_JSON_to_memory_with_vars(JSON_of_inv):
+    inventory = dict_to_mem_data(JSON_of_inv)
+    # Assertions about the variables on the objects
+    assert inventory.get_host('my_host').variables == {'foo': 'bar'}
+    assert inventory.get_group('my_group').variables == {'foobar': 'barfoo'}
+    # Host should be child of group
+    assert inventory.get_host('group_host') in inventory.get_group('my_group').hosts
+
+
+@pytest.mark.inventory_import
+def test_host_lists_accepted(JSON_with_lists):
+    inventory = dict_to_mem_data(JSON_with_lists)
+    assert inventory.get_group('marietta').name == 'marietta'
+    # Check that marietta's hosts was saved
+    h = inventory.get_host('host6.example.com')
+    assert h.name == 'host6.example.com'