Adding dependency injection through injector and flask-injector

Author: robottaway

requirements.txt

@@ -6,3 +6,5 @@ itsdangerous==0.24
 mock==1.0.1
 -e git+ssh://git@git.groovie.org:2222/robottaway/unuo.git@5944a77afc178979cffcb2526daeb1f0d4b96010#egg=unuo-master
 voluptuous==0.8.5
+injector==0.9.0
+Flask-Injector==0.4.0

tests/unuo_tests.py

@@ -4,33 +4,44 @@
 import tempfile
 import shutil
 
-from unuo.factories import default_factory
+from injector import Module
 
 
 logger = logging.getLogger('test')
 logging.basicConfig(level=logging.INFO)
 
 
-class UnuoTests(unittest.TestCase):
+class SimpleModel(Module):
 
-    def setUp(self):
+    def configure(self, binder):
+        from injector import singleton
+        from unuo.filebackend import FileBackend
+        from unuo.ioc import backend_key
         from unuo.config import config
-        self.buildfolder = tempfile.mkdtemp()
-        logger.info('Created temp build dir %s', self.buildfolder)
-        self.logfolder = tempfile.mkdtemp()
-        logger.info('Created temp log dir %s', self.logfolder)
+        binder.bind(
+            backend_key,
+            to=FileBackend(config.builds_folder),
+            scope=singleton)
 
-        config.builds_folder = self.buildfolder
-        config.logs_folder = self.logfolder
 
-        app = default_factory()
+class UnuoTests(unittest.TestCase):
+
+    def setUp(self):
+        from unuo.config import config
+        from unuo.factories import default_factory
+        config.builds_folder = tempfile.mkdtemp()
+        logger.info('Created temp build dir %s', config.builds_folder)
+        config.logs_folder = tempfile.mkdtemp()
+        logger.info('Created temp log dir %s', config.logs_folder)
+        app = default_factory(modules=[SimpleModel])
         self.app = app.test_client()
 
     def tearDown(self):
-        logger.info('Removing temp build dir %s', self.buildfolder)
-        shutil.rmtree(self.buildfolder)
-        logger.info('Removing temp log dir %s', self.logfolder)
-        shutil.rmtree(self.logfolder)
+        from unuo.config import config
+        logger.info('Removing temp build dir %s', config.builds_folder)
+        shutil.rmtree(config.builds_folder)
+        logger.info('Removing temp log dir %s', config.logs_folder)
+        shutil.rmtree(config.logs_folder)
 
     def test_profiles(self):
         rv = self.app.get('/profile')

unuo/blueprints/docker.py

@@ -5,22 +5,18 @@
 """
 import logging
 
-from flask import Blueprint
-from flask import jsonify, request
+from flask import Blueprint, jsonify, request
+from flask.views import View
+from injector import inject
+
 from unuo.errors import ApiError
+from unuo.ioc import backend_key
 
 docker_bp = Blueprint('docker', __name__)
 
-logger = logging.getLogger('test')
-
-backend = None
+logger = logging.getLogger(__name__)
 
 
-def inject_backend(_backend):
-    global backend
-    logger.info('Injecting backend %s', _backend)
-    backend = _backend
-
 # @docker_bp.errorhandler(500)
 # def error_ise(error):
 #     return '{"status_code":500,"description":"oh noes!"}', 500
@@ -35,22 +31,51 @@ def error_json(error):
         error.code, error.description), error.code
 
 
-@docker_bp.route('/build/<name>', methods=['POST'])
-def build(name):
-    """Run given build."""
-    return backend.run_build(name)
+class Builder(View):
+
+    @inject(backend=backend_key)
+    def __init__(self, backend):
+        self.backend = backend
+
+    def dispatch_request(self, name):
+        """Run given build."""
+        return self.backend.run_build(name)
+
+
+docker_bp.add_url_rule(
+    '/build/<name>', methods=['POST'], view_func=Builder.as_view('build'))
+
+
+class ProfileList(View):
+
+    @inject(backend=backend_key)
+    def __init__(self, backend):
+        self.backend = backend
+
+    def dispatch_request(self):
+        """Responsible for listing known builds."""
+        builds = self.backend.get_all_profiles()
+        return jsonify({"builds": builds})
+
+
+docker_bp.add_url_rule(
+    '/profile', methods=['GET'],
+    view_func=ProfileList.as_view('list_build_profiles'))
+
+
+class Profile(View):
 
+    @inject(backend=backend_key)
+    def __init__(self, backend):
+        self.backend = backend
 
-@docker_bp.route('/profile', methods=['GET'])
-def list_build_profiles():
-    """Responsible for listing known builds."""
-    builds = backend.get_all_profiles()
-    return jsonify({"builds": builds})
+    def dispatch_request(self, name):
+        """Responsible for creating/updating builds and launching them."""
+        if request.method == 'POST':
+            return self.backend.post_build(name, request.json)
+        return jsonify(**self.backend.get_build_profile(name))
 
 
-@docker_bp.route('/profile/<name>', methods=['GET', 'POST'])
-def build_container(name):
-    """Responsible for creating/updating builds and launching them."""
-    if request.method == 'POST':
-        return backend.post_build(name, request.json)
-    return jsonify(**backend.get_build_profile(name))
+docker_bp.add_url_rule(
+    '/profile/<name>', methods=['GET', 'POST'],
+    view_func=Profile.as_view('get_profile'))

unuo/factories.py

@@ -3,22 +3,21 @@
 import logging
 
 from flask import Flask
+from flask_injector import FlaskInjector
 
 from unuo.blueprints.docker import docker_bp
-from unuo.filebackend import FileBackend
-from unuo.config import config
+from unuo.ioc import simple_module
 
 logger = logging.getLogger(__name__)
 
 
-def default_factory(conf_env=None, conf_dict=None):
-    from unuo.blueprints.docker import inject_backend
+def default_factory(conf_env=None, conf_dict=None, modules=[simple_module]):
     app = Flask(__name__)
     app.config.from_object('unuo.config.DefaultConfig')
     if conf_dict:
         app.config.update(**conf_dict)
     if conf_env:
         app.config.from_envvar(conf_env)
-    inject_backend(FileBackend(config.builds_folder))
     app.register_blueprint(docker_bp)
+    FlaskInjector(app=app, modules=modules)
     return app

unuo/ioc.py

@@ -0,0 +1,15 @@
+from injector import Key, singleton
+
+from unuo.config import config
+from unuo.filebackend import FileBackend
+
+
+backend_key = Key('unuo_backend')
+
+
+def simple_module(binder):
+    """Setup app using file backend"""
+    binder.bind(
+        backend_key,
+        to=FileBackend(config.builds_folder),
+        scope=singleton)