+ ability to generate the docker tags from setup.py

setup.py

@@ -2,13 +2,86 @@
 # -*- coding: utf-8 -*-
 
 import setuptools
+#from setuptools_scm import get_version
+import re
+
 
 with open("README.md", "r") as fh:
     long_description = fh.read()
 
+
 def local_scheme(version):
     return ""
 
+"""
+    Very specific Docker tag naming for this project
+    This could have been done in Sh, Makefile, ... but here it's integrated
+    with the setup script.
+
+    See https://dankeder.com/posts/adding-custom-commands-to-setup-py/
+    What variables are available from Githu Actions : https://docs.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions#github-context
+"""
+class DockerTagsCommand(setuptools.Command):
+
+    description: "Prints a tag list for the given 'base tag'"
+    user_options = [
+          ('image=', 'i', 'Image name (defaults to nicolabs/nicobot)'),
+          ('variant=', 'v', 'Image variant / base tag : debian|debian-signal|alpine'),
+          ('branch=', 'b', 'The git ref as <branch name> or refs/heads/<branch name>'),
+          ('tag=', 't', 'The git ref as <tag name> or refs/tags/<tag name>'),
+          ('ref=', 'r', 'The git ref as refs/tags|heads/<tag or branch name>'),
+          ('sep=', 's', 'A string to separate each tag in the output (defaults to a new line)'),
+      ]
+
+    def initialize_options(self):
+        self.image = 'nicolabs/nicobot'
+        self.variant = None
+        self.branch = None
+        self.tag = None
+        self.ref = None
+        self.sep = '\n'
+
+    def finalize_options(self):
+        """
+            ref is the backup value for either tag or branch
+            final tag & branch values are normalized anyway
+        """
+
+        stag = self.tag
+        if not stag and self.ref:
+            stag = self.ref
+        try:
+            # If semver, we don't retain the 'v' prefix
+            self.tag = re.search('refs/tags/v?(.*)', stag, flags=re.IGNORECASE).group(1)
+        except:
+            pass
+
+        sbranch = self.branch
+        if not sbranch and self.ref:
+            sbranch = self.ref
+        try:
+            self.branch = re.search('refs/heads/(.*)', sbranch, flags=re.IGNORECASE).group(1)
+        except:
+            pass
+
+    def run(self):
+        # # TODO How to get the actual configuration as set up by setuptools ?
+        # version = get_version(local_scheme='no-local-version')
+        tags = []
+        if self.tag:
+            # When git-tagged, the variant name alone means : the 'latest' for this variant
+            tags = [ "%s:%s" % (self.image,self.variant) ]
+            # It is also tagged with the version
+            tags = tags + [ "%s:%s-%s" % (self.image,self.variant,self.tag) ]
+            # Only debian-signal is tagged with 'latest' additionaly
+            if self.variant == "debian-signal":
+                tags = tags + [ "%s:latest" % (self.image) ]
+        elif self.branch:
+            # All non git-tagged commits overwrite the 'dev' tag (only one is useful currently)
+            tags = tags + [ "%s:%s-dev" % (self.image,self.variant) ]
+        print( self.sep.join(tags) )
+
+
 setuptools.setup(
     # See https://packaging.python.org/tutorials/packaging-projects/
     name="nicobot",
@@ -63,4 +136,7 @@ setuptools.setup(
         # and https://github.com/pypa/setuptools_scm#user-content-version-number-construction
         "local_scheme": 'no-local-version',
     },
+    cmdclass = {
+        'docker_tags': DockerTagsCommand,
+    },
 )