WIP Initial support for parametrization of descriptor files

dogen/cli.py

@@ -56,6 +56,7 @@ def run(self):
         parser.add_argument('--skip-ssl-verification', action='store_true', help='Should we skip SSL verification when retrieving data?')
         parser.add_argument('--scripts-path', help='Location of the scripts directory containing script packages.')
         parser.add_argument('--additional-script', action='append', help='Location of additional script (can be url). Can be specified multiple times.')
+        parser.add_argument('--param', action='append', dest='params', help='List of key and value pairs (format: KEY=value) used for substitution in the image descriptor. Can be specified multiple times.')
         parser.add_argument('--template', help='Path to custom template (can be url)')
 
         parser.add_argument('path', help="Path to yaml descriptor to process")
@@ -69,6 +70,19 @@ def run(self):
         parser.epilog = epilog
         args = parser.parse_args()
 
+        params = {}
+
+        if args.params:
+            for param in args.params:
+                if '=' not in param:
+                    self.log.error("The --param argument with value '%s' could not be parsed. Please make sure you use the 'KEY=value' format" % param)
+                    sys.exit(1)
+
+                k, v = param.split("=", 1)
+                params[k] = v
+
+        args.params = params
+
         if args.verbose:
             self.log.setLevel(logging.DEBUG)
         else:

dogen/generator.py

@@ -1,8 +1,10 @@
 # -*- coding: utf-8 -*-
 
 import hashlib
+import re
 import os
 import shutil
+import six
 import requests
 import yaml
 import tempfile
@@ -29,6 +31,7 @@ def __init__(self, log, args, plugins=[]):
         self.template = args.template
         self.scripts_path = args.scripts_path
         self.additional_scripts = args.additional_script
+        self.params = args.params
 
         ssl_verify = None
         if args.skip_ssl_verification:
@@ -203,7 +206,16 @@ def _validate_cfg(self):
             plugin.extend_schema(schema)
 
         with open(self.descriptor, 'r') as stream:
-            self.cfg = yaml.safe_load(stream)
+            content = stream.read()
+
+            for k, v in six.iteritems(self.params):
+                self.log.debug("Substituting '%s' with '%s' value..." % (k, v))
+                content = re.sub(r"{{%s.*}}" % k, v, content)
+
+            # See if there any params without substitutions. If yes, use specified default values.
+            content = re.sub(r"{{\w+:(.*)}}", '\g<1>', content)
+
+            self.cfg = yaml.safe_load(content)
 
         c = Core(source_data=self.cfg, schema_data=schema)
         try:

tests/test_dockerfile.py

@@ -31,7 +31,7 @@ def setUp(self):
         os.mkdir(self.target)
         self.args = argparse.Namespace(path=self.yaml, output=self.target, without_sources=None,
                                        template=None, scripts_path=None, additional_script=None,
-                                       skip_ssl_verification=None)
+                                       skip_ssl_verification=None, params={})
         with open(self.yaml, 'wb') as f:
             f.write(self.basic_config.encode())
 
@@ -112,9 +112,6 @@ def test_set_entrypoint(self):
             self.assertRegexpMatches(dockerfile, regex)
 
     def test_volumes(self):
-        """
-        Test that cmd: is mapped into a CMD instruction
-        """
         with open(self.yaml, 'ab') as f:
             f.write("volumes:\n  - '/var/lib'\n  - '/usr/lib'".encode())
 
@@ -128,3 +125,53 @@ def test_volumes(self):
             dockerfile = f.read()
             regex = re.compile(r'.*VOLUME \["/var/lib"\]\nVOLUME \["/usr/lib"\]',  re.MULTILINE)
             self.assertRegexpMatches(dockerfile, regex)
+
+    def test_default_substitution(self):
+        with open(self.yaml, 'ab') as f:
+            f.write("from: {{FROM:rhel:7}}\nversion: 1.0".encode())
+
+        generator = Generator(self.log, self.args)
+        generator.configure()
+        generator.render_from_template()
+
+        self.assertEqual(generator.cfg['from'], 'rhel:7')
+
+        with open(os.path.join(self.target, "Dockerfile"), "r") as f:
+            dockerfile = f.read()
+            regex = re.compile(r'.*FROM rhel:7',  re.MULTILINE)
+            self.assertRegexpMatches(dockerfile, regex)
+
+    def test_substitution_with_parameters(self):
+        with open(self.yaml, 'ab') as f:
+            f.write("from: {{FROM:rhel:7}}\nversion: 1.0".encode())
+
+        self.args.params = {'FROM': 'centos:7'}
+
+        generator = Generator(self.log, self.args)
+        generator.configure()
+        generator.render_from_template()
+
+        self.assertEqual(generator.cfg['from'], 'centos:7')
+
+        with open(os.path.join(self.target, "Dockerfile"), "r") as f:
+            dockerfile = f.read()
+            regex = re.compile(r'.*FROM centos:7',  re.MULTILINE)
+            self.assertRegexpMatches(dockerfile, regex)
+
+    def test_substitution_of_multiple_parameters(self):
+        with open(self.yaml, 'ab') as f:
+            f.write("from: rhel:7\ndescription: 'Image {{VERSION}}'\nenvs:\n  information:\n    - name: VERSION\n      value: {{VERSION}}\n".encode())
+
+        self.args.params = {'VERSION': '1.0'}
+
+        generator = Generator(self.log, self.args)
+        generator.configure()
+        generator.render_from_template()
+
+        self.assertEqual(generator.cfg['description'], 'Image 1.0')
+        self.assertEqual(generator.cfg['envs']['information'], [{'name': 'VERSION', 'value': 1.0}])
+
+        with open(os.path.join(self.target, "Dockerfile"), "r") as f:
+            dockerfile = f.read()
+            regex = re.compile(r'.*VERSION="1.0".*',  re.MULTILINE)
+            self.assertRegexpMatches(dockerfile, regex)

tests/test_package.py

@@ -26,7 +26,7 @@ def write_config(self, config):
     def prepare_dogen(self, repo_files_dir=None):
         args = argparse.Namespace(path=self.descriptor.name, output=self.target_dir, without_sources=None,
                                   template=None, scripts_path=None, additional_script=None,
-                                  skip_ssl_verification=None, repo_files_dir=repo_files_dir)
+                                  skip_ssl_verification=None, repo_files_dir=repo_files_dir, params={})
         self.dogen = Generator(self.log, args, [Repo])
 
     def test_custom_repo_files_should_add_two(self):

tests/test_plugin_repo.py

@@ -32,7 +32,7 @@ def write_config(self, config):
     def prepare_dogen(self, repo_files_dir=None):
         args = argparse.Namespace(path=self.descriptor.name, output=self.target_dir, without_sources=None,
                                   template=None, scripts_path=None, additional_script=None,
-                                  skip_ssl_verification=None, repo_files_dir=repo_files_dir)
+                                  skip_ssl_verification=None, repo_files_dir=repo_files_dir, params={})
         self.dogen = Generator(self.log, args, [Repo])
 
     def test_should_skip_plugin_if_no_path_to_repo_is_provided(self):

tests/test_schema.py

@@ -13,7 +13,7 @@ def gen_test(path, good):
             def test(self):
                 args = argparse.Namespace(path=path, output="target", without_sources=None,
                                           template=None, scripts_path=None, additional_script=None,
-                                          skip_ssl_verification=None)
+                                          skip_ssl_verification=None, params={})
                 generator = Generator(self.log, args)
                 if good:
                     generator.configure()

tests/test_unit_generate_configuration.py

@@ -20,7 +20,7 @@ def setUp(self):
         self.descriptor.write(self.basic_config.encode())
         self.args = argparse.Namespace(path=self.descriptor.name, output="target", without_sources=False,
                                        template=None, scripts_path=None, additional_script=None,
-                                       skip_ssl_verification=None)
+                                       skip_ssl_verification=None, params={})
     def tearDown(self):
         os.remove(self.descriptor.name)
 

tests/test_unit_generate_handle_files.py

@@ -12,7 +12,7 @@ def setUp(self):
         self.log = mock.Mock()
         args = argparse.Namespace(path="image.yaml", output="target", without_sources=None,
                                   template=None, scripts_path=None, additional_script=None,
-                                  skip_ssl_verification=None)
+                                  skip_ssl_verification=None, params={})
         self.generator = Generator(self.log, args)
 
     def test_local_file(self):
@@ -29,7 +29,7 @@ def setUp(self):
         self.log = mock.Mock()
         args = argparse.Namespace(path="image.yaml", output="target", without_sources=None,
                                   template=None, scripts_path=None, additional_script=None,
-                                  skip_ssl_verification=None)
+                                  skip_ssl_verification=None, params={})
         self.generator = Generator(self.log, args)
 
     @mock.patch('dogen.generator.requests.get')
@@ -72,13 +72,13 @@ def setUp(self):
         self.log = mock.Mock()
         args = argparse.Namespace(path="image.yaml", output="target", without_sources=None,
                                   template="http://host/custom-template", scripts_path=None,
-                                  additional_script=None, skip_ssl_verification=None)
+                                  additional_script=None, skip_ssl_verification=None, params={})
         self.generator = Generator(self.log, args)
 
     def test_do_not_fail_if_no_template_is_provided(self):
         args = argparse.Namespace(path="image.yaml", output="target", without_sources=None,
                                   template=None, scripts_path=None, additional_script=None,
-                                  skip_ssl_verification=None)
+                                  skip_ssl_verification=None, params={})
         self.generator = Generator(self.log, args)
 
         fetch_file_mock = mock.Mock()