Adds json schema methods to Option and Config

Config schema methods generate a json schemas based on
the config instance's options. Option schema methods
generate schemas based on the type of Option, its
default values, and whether its required or not.

Also adds schema unit tests for Config and Options,
and adds test_float unit test file.

Needed for Freeseer#632

src/freeseer/framework/config/core.py

@@ -3,7 +3,7 @@
 
 # freeseer - vga/presentation capture software
 #
-#  Copyright (C) 2011, 2013  Free and Open Source Software Learning Centre
+#  Copyright (C) 2011, 2013, 2014 Free and Open Source Software Learning Centre
 #  http://fosslc.org
 #
 #  This program is free software: you can redistribute it and/or modify
@@ -56,6 +56,13 @@ def presentation(self, value):
         """Returns a modified version of value that will not itself be persisted."""
         return value
 
+    def schema(self):
+        """Returns the json schema for an Option."""
+        schema = {'type': self.SCHEMA_TYPE}
+        if self.default != self.NotSpecified:
+            schema['default'] = self.default
+        return schema
+
     # Override these!
 
     @abc.abstractmethod
@@ -193,6 +200,26 @@ def save(self):
         else:
             raise StorageNotSetError()
 
+    @classmethod
+    def schema(cls):
+        """Returns the json schema for this Config instance."""
+        required = []
+
+        schema = {
+            'type': 'object',
+            'properties': {},
+        }
+
+        for name, instance in cls.options.iteritems():
+            schema['properties'][name] = instance.schema()
+            if instance.is_required():
+                required.append(name)
+
+        if required:
+            schema['required'] = required
+
+        return schema
+
 
 class ConfigStorage(object):
     """Defines an interface for loading and storing Config instances."""

src/freeseer/framework/config/options.py

@@ -3,7 +3,7 @@
 
 # freeseer - vga/presentation capture software
 #
-#  Copyright (C) 2011, 2013  Free and Open Source Software Learning Centre
+#  Copyright (C) 2011, 2013, 2014 Free and Open Source Software Learning Centre
 #  http://fosslc.org
 #
 #  This program is free software: you can redistribute it and/or modify
@@ -30,6 +30,7 @@
 
 class StringOption(Option):
     """Represents a string value."""
+    SCHEMA_TYPE = 'string'
 
     def is_valid(self, value):
         return isinstance(value, str) or hasattr(value, '__str__')
@@ -43,6 +44,7 @@ def decode(self, value):
 
 class IntegerOption(Option):
     """Represents an integer number value."""
+    SCHEMA_TYPE = 'integer'
 
     def is_valid(self, value):
         return isinstance(value, int)
@@ -59,6 +61,7 @@ def decode(self, value):
 
 class FloatOption(Option):
     """Represents a floating point number value."""
+    SCHEMA_TYPE = 'number'
 
     def is_valid(self, value):
         return isinstance(value, float)
@@ -75,6 +78,7 @@ def decode(self, value):
 
 class BooleanOption(Option):
     """Represents a boolean value."""
+    SCHEMA_TYPE = 'boolean'
 
     def is_valid(self, value):
         return isinstance(value, bool)
@@ -88,6 +92,7 @@ def decode(self, value):
 
 class FolderOption(Option):
     """Represents the path to a folder."""
+    SCHEMA_TYPE = 'string'
 
     def __init__(self, default=Option.NotSpecified, auto_create=False):
         self.auto_create = auto_create
@@ -119,6 +124,7 @@ def presentation(self, value):
 
 class ChoiceOption(StringOption):
     """Represents a selection from a pre-defined list of strings."""
+    SCHEMA_TYPE = 'enum'
 
     def __init__(self, choices, default=Option.NotSpecified):
         self.choices = choices
@@ -133,3 +139,9 @@ def decode(self, value):
             return choice
         else:
             raise InvalidDecodeValueError(value)
+
+    def schema(self):
+        schema = {'enum': self.choices}
+        if self.default != Option.NotSpecified:
+            schema['default'] = self.default
+        return schema

src/freeseer/tests/framework/config/options/test_boolean.py

@@ -3,7 +3,7 @@
 
 # freeseer - vga/presentation capture software
 #
-#  Copyright (C) 2011, 2013  Free and Open Source Software Learning Centre
+#  Copyright (C) 2011, 2013, 2014 Free and Open Source Software Learning Centre
 #  http://fosslc.org
 #
 #  This program is free software: you can redistribute it and/or modify
@@ -24,6 +24,9 @@
 
 import unittest
 
+from jsonschema import validate
+from jsonschema import ValidationError
+
 from freeseer.framework.config.options import BooleanOption
 from freeseer.tests.framework.config.options import OptionTest
 
@@ -53,6 +56,12 @@ class TestBooleanOptionNoDefault(unittest.TestCase, OptionTest):
     def setUp(self):
         self.option = BooleanOption()
 
+    def test_schema(self):
+        """Tests BooleanOption schema method."""
+        self.assertRaises(ValidationError, validate, 4, self.option.schema())
+        self.assertIsNone(validate(True, self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'type': 'boolean'})
+
 
 class TestBooleanOptionWithDefault(TestBooleanOptionNoDefault):
     """Test BooleanOption with a default value."""
@@ -63,3 +72,9 @@ def setUp(self):
     def test_default(self):
         """Tests that the default was set correctly."""
         self.assertEqual(self.option.default, False)
+
+    def test_schema(self):
+        """Tests BooleanOption schema method."""
+        self.assertRaises(ValidationError, validate, 4, self.option.schema())
+        self.assertIsNone(validate(True, self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'default': False, 'type': 'boolean'})

src/freeseer/tests/framework/config/options/test_choice.py

@@ -3,7 +3,7 @@
 
 # freeseer - vga/presentation capture software
 #
-#  Copyright (C) 2011, 2013  Free and Open Source Software Learning Centre
+#  Copyright (C) 2011, 2013, 2014 Free and Open Source Software Learning Centre
 #  http://fosslc.org
 #
 #  This program is free software: you can redistribute it and/or modify
@@ -24,6 +24,9 @@
 
 import unittest
 
+from jsonschema import validate
+from jsonschema import ValidationError
+
 from freeseer.framework.config.options import ChoiceOption
 from freeseer.tests.framework.config.options import OptionTest
 
@@ -52,6 +55,18 @@ def setUp(self):
             'world',
         ])
 
+    def test_schema(self):
+        """Tests a ChoiceOption schema method."""
+        expected = {
+            'enum': [
+                'hello',
+                'world',
+            ],
+        }
+        self.assertRaises(ValidationError, validate, 'error', self.option.schema())
+        self.assertIsNone(validate('world', self.option.schema()))
+        self.assertDictEqual(self.option.schema(), expected)
+
 
 class TestChoiceOptionWithDefault(TestChoiceOptionNoDefault):
     """Tests ChoiceOption with a default value."""
@@ -65,3 +80,16 @@ def setUp(self):
     def test_default(self):
         """Tests that the default was set correctly."""
         self.assertEqual(self.option.default, 'hello')
+
+    def test_schema(self):
+        """Tests a ChoiceOption schema method."""
+        expected = {
+            'default': 'hello',
+            'enum': [
+                'hello',
+                'world',
+            ],
+        }
+        self.assertRaises(ValidationError, validate, 'error', self.option.schema())
+        self.assertIsNone(validate('world', self.option.schema()))
+        self.assertDictEqual(self.option.schema(), expected)

src/freeseer/tests/framework/config/options/test_float.py

@@ -0,0 +1,72 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# freeseer - vga/presentation capture software
+#
+#  Copyright (C) 2014 Free and Open Source Software Learning Centre
+#  http://fosslc.org
+#
+#  This program is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# For support, questions, suggestions or any other inquiries, visit:
+# http://wiki.github.com/Freeseer/freeseer/
+
+import unittest
+
+from jsonschema import validate
+from jsonschema import ValidationError
+
+from freeseer.framework.config.options import FloatOption
+from freeseer.tests.framework.config.options import OptionTest
+
+
+class TestFloatOptionNoDefault(unittest.TestCase, OptionTest):
+    """Tests FloatOption without a default value."""
+
+    valid_success = [x / 10.0 for x in xrange(-100, 100)]
+
+    encode_success = zip(valid_success, map(str, valid_success))
+
+    decode_success = zip(map(str, valid_success), valid_success)
+    decode_failure = [
+        'hello',
+        '1world',
+        'test2',
+    ]
+
+    def setUp(self):
+        self.option = FloatOption()
+
+    def test_schema(self):
+        """Tests FloatOption schema method."""
+        self.assertRaises(ValidationError, validate, 'error', self.option.schema())
+        self.assertIsNone(validate(5.5, self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'type': 'number'})
+
+
+class TestFloatOptionWithDefault(TestFloatOptionNoDefault):
+    """Tests FloatOption with a default value."""
+
+    def setUp(self):
+        self.option = FloatOption(1234.5)
+
+    def test_default(self):
+        """Tests that the default was set correctly."""
+        self.assertEqual(self.option.default, 1234.5)
+
+    def test_schema(self):
+        """Tests FloatOption schema method."""
+        self.assertRaises(ValidationError, validate, 'error', self.option.schema())
+        self.assertIsNone(validate(5.0, self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'default': 1234.5, 'type': 'number'})

src/freeseer/tests/framework/config/options/test_folder.py

@@ -3,7 +3,7 @@
 
 # freeseer - vga/presentation capture software
 #
-#  Copyright (C) 2011, 2013  Free and Open Source Software Learning Centre
+#  Copyright (C) 2011, 2013, 2014 Free and Open Source Software Learning Centre
 #  http://fosslc.org
 #
 #  This program is free software: you can redistribute it and/or modify
@@ -27,6 +27,9 @@
 import tempfile
 import unittest
 
+from jsonschema import validate
+from jsonschema import ValidationError
+
 from freeseer.framework.config.options import FolderOption
 from freeseer.tests.framework.config.options import OptionTest
 
@@ -57,6 +60,12 @@ def test_presentation(self):
         self.assertEqual(presentation_value, path)
         self.assertFalse(os.path.exists(presentation_value))
 
+    def test_schema(self):
+        """Tests StringOption schema method."""
+        self.assertRaises(ValidationError, validate, 1, self.option.schema())
+        self.assertIsNone(validate('/tmp2', self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'type': 'string'})
+
 
 class TestFolderOptionAutoCreate(TestFolderOptionNoDefault):
     """Tests FolderOption without a default value, and with auto_create turned on."""
@@ -88,3 +97,9 @@ def setUp(self):
     def test_default(self):
         """Tests that the default was set correctly."""
         self.assertEqual(self.option.default, '/tmp')
+
+    def test_schema(self):
+        """Tests StringOption schema method."""
+        self.assertRaises(ValidationError, validate, 1, self.option.schema())
+        self.assertIsNone(validate('/tmp2', self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'default': '/tmp', 'type': 'string'})

src/freeseer/tests/framework/config/options/test_integer.py

@@ -3,7 +3,7 @@
 
 # freeseer - vga/presentation capture software
 #
-#  Copyright (C) 2011, 2013  Free and Open Source Software Learning Centre
+#  Copyright (C) 2011, 2013, 2014 Free and Open Source Software Learning Centre
 #  http://fosslc.org
 #
 #  This program is free software: you can redistribute it and/or modify
@@ -24,6 +24,9 @@
 
 import unittest
 
+from jsonschema import validate
+from jsonschema import ValidationError
+
 from freeseer.framework.config.options import IntegerOption
 from freeseer.tests.framework.config.options import OptionTest
 
@@ -45,6 +48,12 @@ class TestIntegerOptionNoDefault(unittest.TestCase, OptionTest):
     def setUp(self):
         self.option = IntegerOption()
 
+    def test_schema(self):
+        """Tests IntegerOption schema method."""
+        self.assertRaises(ValidationError, validate, 1.0, self.option.schema())
+        self.assertIsNone(validate(5, self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'type': 'integer'})
+
 
 class TestIntegerOptionWithDefault(TestIntegerOptionNoDefault):
     """Tests IntegerOption with a default value."""
@@ -55,3 +64,9 @@ def setUp(self):
     def test_default(self):
         """Tests that the default was set correctly."""
         self.assertEqual(self.option.default, 1234)
+
+    def test_schema(self):
+        """Tests IntegerOption schema method."""
+        self.assertRaises(ValidationError, validate, 1.0, self.option.schema())
+        self.assertIsNone(validate(5, self.option.schema()))
+        self.assertDictEqual(self.option.schema(), {'default': 1234, 'type': 'integer'})