Use backed by go-jsonnet for python extension

.gitignore

@@ -1,8 +1,13 @@
 *~
 *.prof
 *.so
+*.a
 .*.swp
+*.pyc
 coverage.out
+build/
+dist/
+jsonnet.egg-info/
 /bazel-bin
 /bazel-genfiles
 /bazel-go-jsonnet

c-bindings/BUILD.bazel

@@ -12,6 +12,7 @@ load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
 go_library(
     name = "go_default_library",
     srcs = [
+        "handles.go",
         "c-bindings.go",
         "internal.h",
         "json.cpp",

python/_jsonnet_test.py

@@ -0,0 +1,97 @@
+# Copyright 2015 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+import unittest
+
+import _jsonnet
+
+
+#  Returns content if worked, None if file not found, or throws an exception
+def try_path(dir, rel):
+    if not rel:
+        raise RuntimeError('Got invalid filename (empty string).')
+    if rel[0] == '/':
+        full_path = rel
+    else:
+        full_path = dir + rel
+    if full_path[-1] == '/':
+        raise RuntimeError('Attempted to import a directory')
+
+    if not os.path.isfile(full_path):
+        return full_path, None
+    with open(full_path) as f:
+        return full_path, f.read()
+
+
+def import_callback(dir, rel):
+    full_path, content = try_path(dir, rel)
+    if content:
+        return full_path, content
+    raise RuntimeError('File not found')
+
+
+# Test native extensions
+def concat(a, b):
+    return a + b
+
+
+def return_types():
+    return {
+        'a': [1, 2, 3, None, []],
+        'b': 1.0,
+        'c': True,
+        'd': None,
+        'e': {
+            'x': 1,
+            'y': 2,
+            'z': ['foo']
+        },
+    }
+
+native_callbacks = {
+    'concat': (('a', 'b'), concat),
+    'return_types': ((), return_types),
+}
+
+
+class JsonnetTests(unittest.TestCase):
+    def setUp(self):
+        self.input_filename = os.path.join(
+            os.path.dirname(__file__),
+            "test.jsonnet",
+        )
+        self.expected_str = "true\n"
+        with open(self.input_filename, "r") as infile:
+            self.input_snippet = infile.read()
+
+    def test_evaluate_file(self):
+        json_str = _jsonnet.evaluate_file(
+            self.input_filename,
+            import_callback=import_callback,
+            native_callbacks=native_callbacks,
+        )
+        self.assertEqual(json_str, self.expected_str)
+
+    def test_evaluate_snippet(self):
+        json_str = _jsonnet.evaluate_snippet(
+            "snippet",
+            self.input_snippet,
+            import_callback=import_callback,
+            native_callbacks=native_callbacks,
+        )
+        self.assertEqual(json_str, self.expected_str)
+
+if __name__ == '__main__':
+    unittest.main()

python/test.jsonnet

@@ -0,0 +1,5 @@
+std.assertEqual(({ x: 1, y: self.x } { x: 2 }).y, 2) &&
+std.assertEqual(std.native("concat")("foo", "bar"), "foobar") &&
+std.assertEqual(std.native("return_types")(), {a: [1, 2, 3, null, []], b: 1, c: true, d: null, e: {x: 1, y: 2, z: ["foo"]}}) &&
+true
+

setup.py

@@ -0,0 +1,60 @@
+# Copyright 2015 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+from setuptools import setup
+from setuptools import Extension
+from setuptools.command.build_ext import build_ext as BuildExt
+from subprocess import Popen, PIPE
+
+DIR = os.path.abspath(os.path.dirname(__file__))
+LIB_DIR = DIR + '/c-bindings'
+MODULE_SOURCES = ['cpp-jsonnet/python/_jsonnet.c']
+
+def get_version():
+    # TODO think about it (how to get the version)
+    return '0.14.0'
+
+class BuildJsonnetExt(BuildExt):
+    def run(self):
+        p = Popen(['go', 'build', '-o', 'libgojsonnet.a', '-buildmode=c-archive'], cwd=LIB_DIR, stdout=PIPE)
+        p.wait()
+
+        if p.returncode != 0:
+            raise Exception('Could not build libgojsonnet.so')
+
+        BuildExt.run(self)
+
+jsonnet_ext = Extension(
+    '_jsonnet',
+    sources=MODULE_SOURCES,
+    extra_objects=[
+        LIB_DIR + '/libgojsonnet.a',
+    ],
+    include_dirs = ['cpp-jsonnet/include'],
+    language='c++',
+)
+
+setup(name='jsonnet',
+    url='https://jsonnet.org',
+    description='Python bindings for Jsonnet - The data templating language ',
+    author='David Cunningham',
+    author_email='dcunnin@google.com',
+    version=get_version(),
+    cmdclass={
+        'build_ext': BuildJsonnetExt,
+    },
+    ext_modules=[jsonnet_ext],
+    test_suite="python._jsonnet_test",
+)