Merge branch 'release/1.0'

README.md

@@ -0,0 +1,52 @@
+# Pyventory
+Ansible Inventory implementation that uses Python syntax
+
+## Install
+
+```shell
+pip install pyventory
+```   
+
+## Featur e
+
+* Modular inventor  y.
+* Assests inheritance using Python classe s.
+* Support for multiple inheritance  .
+* Support for mixins  .
+* Support for vars templating using [Python string formatting](https://docs.python.org/3/library/string.html#format-specification-mini-language)  .
+* Python 3 support
+* Python 2 (2.7) support
+
+
+## Usage
+
+Create `hosts.py` and make it executable.
+
+A short example of the `hosts.py` contents:
+
+```python
+#!/usr/bin/env python
+from pyventory import export_inventory
+
+class All(Asset):
+    run_tests = False
+    use_redis = False
+    redis_host = 'localhost'
+    minify = False
+    version = 'develop'
+
+class Staging(All):
+    run_tests = True
+
+staging = Staging()
+
+export_inventory(locals())
+```
+
+Consider a [more complex example](tests/e2e/example) which passes the following [json output](tests/e2e/example.json) to Ansible.
+
+Run Ansible playbook with the `-i hosts.py` key:
+
+```shell
+ansible-playbook -i hosts.py site.yml
+```

pyventory/inventory.py

@@ -1,20 +1,22 @@
 import json
+import string
 import sys
 
 import attr
+import six
 
 
-__all__ = ['InventoryItem', 'export_inventory']
+__all__ = ['Asset', 'export_inventory']
 
 
 @attr.s
-class GroupData:
+class GroupData(object):
     hosts = attr.ib(default=attr.Factory(set))
     vars = attr.ib(default=attr.Factory(dict))
     children = attr.ib(default=attr.Factory(set))
 
 
-class Inventory:
+class Inventory(object):
     group_registry = {}
 
     def __init__(self, hosts):
@@ -28,7 +30,11 @@ def add_host(self, name, host):
         self.hosts[name] = host._host_vars
 
         for group in host.__class__.__bases__:
-            group_name = group.__qualname__
+            group_name = group.__name__
+
+            # skip mixins
+            if group_name not in self.group_registry:
+                continue
 
             if group_name not in self.groups:
                 self.add_group(group_name)
@@ -52,6 +58,7 @@ def export(self, sort=False):
             group['children'] = list(
                 set(group['children']).intersection(data.keys()))
             if sort:
+                group['hosts'].sort()
                 group['children'].sort()
             for attr_name in ('hosts', 'vars', 'children',):
                 if not group[attr_name]:
@@ -62,12 +69,12 @@ def export(self, sort=False):
 
     @classmethod
     def register_group(cls, item):
-        cls.group_registry[item.__qualname__] = GroupData(
+        cls.group_registry[item.__name__] = GroupData(
             vars=item._group_vars())
 
     @classmethod
     def register_child(cls, item, parent):
-        cls.group_registry[parent.__qualname__].children.add(item.__qualname__)
+        cls.group_registry[parent.__name__].children.add(item.__name__)
 
     @classmethod
     def _get_parent_names(cls, name):
@@ -80,30 +87,42 @@ def _get_parent_names(cls, name):
         return parent_names
 
 
-class InventoryItemMeta(type):
+class AssetMeta(type):
 
     def __new__(cls, name, bases, attrs):
-        item = super().__new__(cls, name, bases, attrs)
+        item = super(AssetMeta, cls).__new__(cls, name, bases, attrs)
         if not bases:
             return item
 
         Inventory.register_group(item)
 
         for base in bases:
-            if not issubclass(base, InventoryItem):
+            if not issubclass(base, Asset):
                 continue
-            if base is InventoryItem:
+            if base is Asset:
                 continue
             Inventory.register_child(item, base)
 
         return item
 
 
-class InventoryItem(metaclass=InventoryItemMeta):
-    __template_vars = None  # typing: list
+class Asset(six.with_metaclass(AssetMeta)):
 
     def __init__(self, **kwargs):
         var_data = self._group_vars()
+
+        for template_name, template_vars in self._template_map().items():
+            try:
+                template_data = {var: kwargs.pop(var) for var in template_vars}
+            except KeyError:
+                raise ValueError(
+                    'Not enough arguments for template `%s`: "%s"',
+                    template_name,
+                    var_data[template_name])
+
+            var_data[template_name] = var_data[template_name].format(
+                **template_data)
+
         var_data.update(kwargs)
         self._host_vars = var_data
 
@@ -114,14 +133,32 @@ def _group_vars(cls):
             for name, value in vars(cls).items()
             if not name.startswith('_')}
 
+    @classmethod
+    def _template_map(cls):
+        formatter = string.Formatter()
+        template_map = {}
+
+        for name, value in cls._group_vars().items():
+            template_vars = [
+                chunk[1]
+                for chunk in formatter.parse(value)
+                if chunk[1] is not None]
+
+            if not template_vars:
+                continue
+
+            template_map[name] = template_vars
+
+        return template_map
+
 
-def export_inventory(hosts, indent=None, sort=True):
+def export_inventory(hosts, out=sys.stdout, indent=None, sort=True):
     inventory = Inventory({
         name: obj
         for name, obj in hosts.items()
-        if isinstance(obj, InventoryItem)})
+        if isinstance(obj, Asset)})
     json.dump(
         inventory.export(sort=sort),
-        sys.stdout,
+        out,
         indent=indent,
         sort_keys=sort)

setup.py

@@ -1,6 +1,13 @@
+import sys
+
 from setuptools import setup, find_packages
 
 
+install_requires = ['six', 'attrs']
+
+if sys.version_info < (3, 4):
+    install_requires.append('pathlib')
+
 setup(
     name='Pyventory',
     use_scm_version=True,
@@ -10,19 +17,24 @@
     author_email='s@matveenko.ru',
     license='BSD',
     classifiers=[
-        'Development Status :: 2 - Pre-Alpha',
+        'Development Status :: 4 - Beta',
         'Intended Audience :: Developers',
         'Intended Audience :: System Administrators',
         'License :: OSI Approved :: BSD License',
-        'Programming Language :: Python :: 3 :: Only',
+        'Programming Language :: Python :: 2',
+        'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.5',
+        'Programming Language :: Python :: 3.6',
         'Topic :: System :: Systems Administration',
     ],
     keywords='devops ansible inventory',
     packages=find_packages(),
-    python_requires='>=3.3',
     setup_requires=['setuptools_scm', 'pytest-runner'],
-    install_requires=['attrs'],
-    tests_require=['pytest'],
+    install_requires=install_requires,
+    extras_require={
+        'test': ['pytest', 'tox'],
+    },
     entry_points={
         'console_scripts': [
             'pyventory=pyventory.cli:main',

tests/e2e/example.json

@@ -3,6 +3,7 @@
         "children": [
             "BackEnd",
             "FrontEnd",
+            "Production",
             "Staging"
         ],
         "vars": {
@@ -15,20 +16,43 @@
     },
     "BackEnd": {
         "hosts": [
-            "develop"
+            "develop",
+            "develop_sidebranch",
+            "prod_backend1",
+            "prod_backend2",
+            "staging"
         ],
         "vars": {
             "use_redis": true
         }
     },
     "FrontEnd": {
         "hosts": [
-            "develop"
+            "develop",
+            "develop_sidebranch",
+            "prod_frontend1",
+            "prod_frontend2",
+            "staging"
         ]
     },
+    "Production": {
+        "hosts": [
+            "prod_backend1",
+            "prod_backend2",
+            "prod_frontend1",
+            "prod_frontend2"
+        ],
+        "vars": {
+            "minify": true,
+            "use_redis": true,
+            "version": "master"
+        }
+    },
     "Staging": {
         "hosts": [
-            "develop"
+            "develop",
+            "develop_sidebranch",
+            "staging"
         ],
         "vars": {
             "run_tests": true
@@ -39,6 +63,28 @@
             "develop": {
                 "ansible_host": "develop_hostname",
                 "version": "develop"
+            },
+            "develop_sidebranch": {
+                "ansible_host": "sidebranch_hostname",
+                "version": "sidebranch_name"
+            },
+            "prod_backend1": {
+                "ansible_hostname": "app001.prod.dom",
+                "redis_host": "prod_redis_hostname"
+            },
+            "prod_backend2": {
+                "ansible_hostname": "app002.prod.dom",
+                "redis_host": "prod_redis_hostname"
+            },
+            "prod_frontend1": {
+                "ansible_hostname": "www001.prod.dom"
+            },
+            "prod_frontend2": {
+                "ansible_hostname": "www002.prod.dom"
+            },
+            "staging": {
+                "ansible_host": "master_hostname",
+                "version": "master"
             }
         }
     }

tests/e2e/example/hosts.py

@@ -1,19 +1,19 @@
-#!/usr/bin/env python3
+#!/usr/bin/env python
 from pyventory import export_inventory
 
 from pyvars import *
 
 
 develop = DevelopHost()
-# develop_sidebranch = DevelopHost(
-#     ansible_host='sidebranch_hostname',
-#     version='sidebranch_name')
-# 
-# staging = StagingHost()
-# 
-# prod_backend1 = ProdBackEnd(num=1)
-# prod_backend2 = ProdBackEnd(num=2)
-# prod_frontend1 = ProdFrontEnd(num=1)
-# prod_frontend2 = ProdFrontEnd(num=2)
+develop_sidebranch = DevelopHost(
+    ansible_host='sidebranch_hostname',
+    version='sidebranch_name')
+
+staging = StagingHost()
+
+prod_backend1 = ProdBackEnd(num=1)
+prod_backend2 = ProdBackEnd(num=2)
+prod_frontend1 = ProdFrontEnd(num=1)
+prod_frontend2 = ProdFrontEnd(num=2)
 
 export_inventory(locals(), indent=4)

tests/e2e/example/pyvars/base_groups.py

@@ -1,7 +1,7 @@
-from pyventory import InventoryItem
+from pyventory import Asset
 
 
-class All(InventoryItem):
+class All(Asset):
     run_tests = False
     use_redis = False
     redis_host = 'localhost'

tests/e2e/test_example.py

@@ -7,19 +7,21 @@
 
 @pytest.fixture(scope='session')
 def example_inventory(tests_dir):
-    return open(str(tests_dir.joinpath('e2e', 'example.json')), 'rb').read()
+    return open(str(tests_dir.joinpath('e2e', 'example.json')), 'r').read()
 
 
 def test_example_inventory(tests_dir, example_inventory):
     project_dir = tests_dir.parent
     example_dir = tests_dir.joinpath('e2e', 'example')
     inventory_exe = example_dir.joinpath('hosts.py')
 
-    result = subprocess.run(
+    result = subprocess.check_output(
         shlex.split(str(inventory_exe)),
-        stdout=subprocess.PIPE,
         env=dict(
             os.environ,
             PYTHONPATH='{}:{}'.format(project_dir, example_dir)))
 
-    assert result.stdout == example_inventory
+    # hack for py27 `json.dump()` behavior
+    result = '\n'.join([x.rstrip() for x in result.decode().split('\n')])
+
+    assert result == example_inventory