Move ImageName from osbs-client to util.

Refactor to keep string behavior identical for parser.

Author: tim-vk

dockerfile_parse/parser.py

@@ -19,7 +19,7 @@
 
 from .constants import DOCKERFILE_FILENAME, COMMENT_INSTRUCTION
 from .util import (b2u, extract_key_values, get_key_val_dictionary,
-                   u2b, Context, WordSplitter)
+                   u2b, Context, WordSplitter, ImageName)
 
 
 logger = logging.getLogger(__name__)
@@ -880,7 +880,9 @@ def image_from(from_value):
         )?
         """)
     match = re.match(regex, from_value)
-    return match.group('image', 'name') if match else (None, None)
+    image = ImageName.parse(match.group('image')) if match else None
+    name = match.group('name') if match else None
+    return image, name
 
 
 def _endline(line):

dockerfile_parse/util.py

@@ -46,15 +46,15 @@ class WordSplitter(object):
     SQUOTE = "'"
     DQUOTE = '"'
 
-    def __init__(self, s, args=None, envs=None):
+    def __init__(self, s: str, args=None, envs=None):
         """
         :param s: str, string to process
         :param args: dict, build arguments to use; if None, do not
             attempt substitution
         :param envs: dict, environment variables to use; if None, do not
             attempt substitution
         """
-        self.stream = StringIO(s)
+        self.stream = StringIO(str(s))
         self.args = args
         self.envs = envs
 
@@ -332,3 +332,125 @@ def get_values(self, context_type):
         if context_type.upper() == "LABEL":
             return self.labels
         raise ValueError("Unexpected context type: " + context_type)
+
+
+class ImageName(object):
+    """Represent an image.
+    Naming Conventions
+    ==================
+    registry.somewhere/namespace/image_name:tag
+    |-----------------|                          registry, reg_uri
+                      |---------|                namespace
+    |--------------------------------------|     repository
+                      |--------------------|     image name
+                                            |--| tag
+                      |------------------------| image
+    |------------------------------------------| image
+    """
+
+    def __init__(self, registry=None, namespace=None, repo=None, tag=None):
+        self.registry = registry
+        self.namespace = namespace
+        self.repo = repo
+        self.tag = tag
+
+    @classmethod
+    def parse(cls, image_name: str):
+        result = cls()
+
+        if not image_name or image_name.isspace():
+            return ImageName()
+
+        if isinstance(image_name, cls):
+            logger.debug("Attempting to parse ImageName %s as an ImageName", image_name)
+            return image_name
+
+        # registry.org/namespace/repo:tag
+        s = image_name.split('/', 2)
+
+        if len(s) == 2:
+            if '.' in s[0] or ':' in s[0]:
+                result.registry = s[0] if s[0] else None
+            else:
+                result.namespace = s[0]
+        elif len(s) == 3:
+            result.registry = s[0] if s[0] else None
+            result.namespace = s[1]
+        result.repo = s[-1]
+
+        for sep in '@:':
+            try:
+                result.repo, result.tag = result.repo.rsplit(sep, 1)
+            except ValueError:
+                continue
+            break
+
+        return result
+
+    def to_str(self, registry=True, tag=True, explicit_tag=False,
+               explicit_namespace=False):
+        if self.repo is None:
+            raise RuntimeError('No image repository specified')
+
+        result = self.get_repo(explicit_namespace)
+
+        if tag and self.tag and ':' in self.tag:
+            result = '{0}@{1}'.format(result, self.tag)
+        elif tag and self.tag:
+            result = '{0}:{1}'.format(result, self.tag)
+        elif tag and explicit_tag:
+            result = '{0}:{1}'.format(result, 'latest')
+
+        if registry and self.registry:
+            result = '{0}/{1}'.format(self.registry, result)
+
+        return result
+
+    def get_repo(self, explicit_namespace=False):
+        result = self.repo
+        if self.namespace:
+            result = '{0}/{1}'.format(self.namespace, result)
+        elif explicit_namespace:
+            result = '{0}/{1}'.format('library', result)
+        return result
+
+    def enclose(self, organization):
+        if self.namespace == organization:
+            return
+
+        repo_parts = [self.repo]
+        if self.namespace:
+            repo_parts.insert(0, self.namespace)
+
+        self.namespace = organization
+        self.repo = '-'.join(repo_parts)
+
+    def __str__(self):
+        return self.to_str(registry=True, tag=True)
+
+    def __repr__(self):
+        return (
+            "ImageName(registry={s.registry!r}, namespace={s.namespace!r},"
+            " repo={s.repo!r}, tag={s.tag!r})"
+        ).format(s=self)
+
+    def __eq__(self, other):
+        if type(other) == str:
+            return self.__str__() == other
+        elif type(other) == type(self):
+            return self.__dict__ == other.__dict__
+        else:
+            return NotImplemented
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash(self.to_str())
+
+    def copy(self):
+        return ImageName(
+            registry=self.registry,
+            namespace=self.namespace,
+            repo=self.repo,
+            tag=self.tag)