Initial extraction of EtcHostsProvider from octoDNS core

CHANGELOG.md

@@ -1,11 +1,9 @@
-## TODO: v0.0.1 - 20??-??-?? - Moving
+## v0.0.1 - 2022-01-09 - Moving
 
 #### Nothworthy Changes
 
 * Initial extraction of EtcHostsProvider from octoDNS core
 
-TODO: anything else
-
 #### Stuff
 
-TODO: anything else
+Nothing

README.md

@@ -1,8 +1,6 @@
-TODO: Review this README and add or modify as necessary.
-
 ## /etc/hosts provider for octoDNS
 
-An [octoDNS](https://github.com/octodns/octodns/) provider that targets [/etc/hosts](https://github.com/octodns/octodns-etchosts/).
+An [octoDNS](https://github.com/octodns/octodns/) provider that creates a "best effort" static/emergency content that can be used in /etc/hosts to resolve things. A, AAAA records are supported and ALIAS and CNAME records will be included when they can be mapped within the zone.
 
 ### Installation
 
@@ -38,21 +36,20 @@ octodns_etchosts==0.0.1
 providers:
   etchosts:
     class: octodns_etchosts.EtcHostsProvider
-    # TODO
+    # The output director for the hosts file <zone>.hosts
+    directory: ./hosts
 ```
 
 ### Support Information
 
 #### Records
 
-TODO: All octoDNS record types are supported.
+EtcHostsProvider supports A and AAAA, and has partial support for tracing ALIAS and CNAME records when they can be resolved within the zone.
 
 #### Dynamic
 
-TODO: EtcHostsProvider does not support dynamic records.
+EtcHostsProvider does not support dynamic records.
 
 ### Developement
 
 See the [/script/](/script/) directory for some tools to help with the development process. They generally follow the [Script to rule them all](https://github.com/github/scripts-to-rule-them-all) pattern. Most useful is `./script/bootstrap` which will create a venv and install both the runtime and development related requirements. It will also hook up a pre-commit hook that covers most of what's run by CI.
-
-TODO: any provider specific setup, a docker compose to run things locally etc?

octodns_etchosts/__init__.py

@@ -2,11 +2,102 @@
 #
 #
 
+from os import makedirs, path
+from os.path import isdir
+from logging import getLogger
+
 from octodns.provider.base import BaseProvider
 
 __VERSION__ = '0.0.1'
 
 
-class EtcHostsProvider(BaseProvider)
-    # TODO: implement things
-    pass
+class EtcHostsProvider(BaseProvider):
+    SUPPORTS_GEO = False
+    SUPPORTS_DYNAMIC = False
+    SUPPORTS = set(('A', 'AAAA', 'ALIAS', 'CNAME'))
+
+    def __init__(self, id, directory, *args, **kwargs):
+        self.log = getLogger(f'EtcHostsProvider[{id}]')
+        self.log.debug('__init__: id=%s, directory=%s', id, directory)
+        super(EtcHostsProvider, self).__init__(id, *args, **kwargs)
+        self.directory = directory
+
+    def populate(self, zone, target=False, lenient=False):
+        self.log.debug('populate: name=%s, target=%s, lenient=%s', zone.name,
+                       target, lenient)
+
+        # We never act as a source, at least for now, if/when we do we still
+        # need to noop `if target`
+        return False
+
+    def _apply(self, plan):
+        desired = plan.desired
+        changes = plan.changes
+        self.log.debug('_apply: zone=%s, len(changes)=%d', desired.name,
+                       len(changes))
+        cnames = {}
+        values = {}
+        for record in sorted([c.new for c in changes]):
+            # Since we don't have existing we'll only see creates
+            fqdn = record.fqdn[:-1]
+            if record._type in ('ALIAS', 'CNAME'):
+                # Store cnames so we can try and look them up in a minute
+                cnames[fqdn] = record.value[:-1]
+            elif record._type == 'AAAA' and fqdn in values:
+                # We'll prefer A over AAAA, skipping rather than replacing an
+                # existing A
+                pass
+            else:
+                # If we're here it's and A or AAAA and we want to record it's
+                # value (maybe replacing if it's an A and we have a AAAA
+                values[fqdn] = record.values[0]
+
+        if not isdir(self.directory):
+            makedirs(self.directory)
+
+        filepath = path.join(self.directory, desired.name)
+        filename = f'{filepath}hosts'
+        self.log.info('_apply: filename=%s', filename)
+        with open(filename, 'w') as fh:
+            fh.write('##################################################\n')
+            fh.write(f'# octoDNS {self.id} {desired.name}\n')
+            fh.write('##################################################\n\n')
+            if values:
+                fh.write('## A & AAAA\n\n')
+                for fqdn, value in sorted(values.items()):
+                    if fqdn[0] == '*':
+                        fh.write('# ')
+                    fh.write(f'{value}\t{fqdn}\n\n')
+
+            if cnames:
+                fh.write('\n## CNAME (mapped)\n\n')
+                for fqdn, value in sorted(cnames.items()):
+                    # Print out a comment of the first level
+                    fh.write(f'# {fqdn} -> {value}\n')
+                    seen = set()
+                    while True:
+                        seen.add(value)
+                        try:
+                            value = values[value]
+                            # If we're here we've found the target, print it
+                            # and break the loop
+                            fh.write(f'{value}\t{fqdn}\n')
+                            break
+                        except KeyError:
+                            # Try and step down one level
+                            orig = value
+                            value = cnames.get(value, None)
+                            # Print out this step
+                            if value:
+                                if value in seen:
+                                    # We'd loop here, break it
+                                    fh.write(f'# {orig} -> {value} **loop**\n')
+                                    break
+                                else:
+                                    fh.write(f'# {orig} -> {value}\n')
+                            else:
+                                # Don't have anywhere else to go
+                                fh.write(f'# {orig} -> **unknown**\n')
+                                break
+
+                    fh.write('\n')

requirements-dev.txt

@@ -1,8 +1,21 @@
+Pygments==2.11.2
+bleach==4.1.0
 build==0.7.0
+colorama==0.4.4
+docutils==0.18.1
+importlib-metadata==4.10.0
+keyring==23.5.0
 nose-no-network==0.0.1
 nose-timer==1.0.1
 nose==1.3.7
+pep517==0.12.0
+pkginfo==1.8.2
 pycodestyle==2.6.0
 pyflakes==2.2.0
+readme-renderer==32.0
+requests-toolbelt==0.9.1
+rfc3986==1.5.0
+tqdm==4.62.3
 twine==3.7.1
-# TODO: add any other test-time requirements, these should be exhaustive and pinned 
+webencodings==0.5.1
+zipp==3.7.0

requirements.txt

@@ -1,2 +1,28 @@
+PyYAML==6.0
+attrs==21.4.0
+certifi==2021.10.8
+charset-normalizer==2.0.10
+coverage==6.2
+dnspython==2.1.0
+fqdn==1.5.1
+idna==3.3
+iniconfig==1.1.1
+natsort==8.0.2
 octodns==0.9.14
-# TODO: add any other runtime requirements, these should be exhaustive and pinned 
+packaging==21.3
+pluggy==1.0.0
+pprintpp==0.4.0
+py==1.11.0
+pycountry-convert==0.7.2
+pycountry==20.7.3
+pyparsing==3.0.6
+pytest-cov==3.0.0
+pytest-mock==3.6.1
+pytest==6.2.5
+python-dateutil==2.8.2
+repoze.lru==0.7
+requests==2.27.1
+six==1.16.0
+toml==0.10.2
+tomli==2.0.0
+urllib3==1.26.8

setup.py

@@ -27,12 +27,11 @@ def version():
     name='octodns-etchosts',
     packages=('octodns_etchosts',),
     python_requires='>=3.6',
-    install_requires=('octodns>=0.9.14', 'TODO: other requirements'),
+    install_requires=('octodns>=0.9.14'),
     url='https://github.com/octodns/octodns-etchosts',
     version=version(),
     tests_require=(
         'nose',
         'nose-no-network',
-        'TODO: other test-time requirements'
     ),
 )