Version checker (#3102)

* Updates for docker version check script:

- Do not run on a push to stable
- Check existing versions via GitHub API
- Add stable docker image tag also

* Fix regex pattern

* Check for null regex result

* Push to stable on tagged release

ci/version_check.py

@@ -0,0 +1,171 @@
+"""
+Ensure that the release tag matches the InvenTree version number:
+
+master / main branch:
+    - version number must end with 'dev'
+
+tagged branch:
+    - version number must match tag being built
+    - version number cannot already exist as a release tag
+
+"""
+
+import json
+import os
+import re
+import sys
+
+import requests
+
+
+def get_existing_release_tags():
+    """Request information on existing releases via the GitHub API"""
+
+    response = requests.get('https://api.github.com/repos/inventree/inventree/releases')
+
+    if response.status_code != 200:
+        raise ValueError(f'Unexpected status code from GitHub API: {response.status_code}')
+
+    data = json.loads(response.text)
+
+    # Return a list of all tags
+    tags = []
+
+    for release in data:
+        tag = release['tag_name'].strip()
+        match = re.match(r"^.*(\d+)\.(\d+)\.(\d+).*$", tag)
+
+        if len(match.groups()) != 3:
+            print(f"Version '{tag}' did not match expected pattern")
+            continue
+
+        tags.append([int(x) for x in match.groups()])
+
+    return tags
+
+
+def check_version_number(version_string):
+    """Check the provided version number.
+
+    Returns True if the provided version is the 'newest' InvenTree release
+    """
+
+    print(f"Checking version '{version_string}'")
+
+    # Check that the version string matches the required format
+    match = re.match(r"^(\d+)\.(\d+)\.(\d+)(?: dev)?$", version_string)
+
+    if not match or len(match.groups()) != 3:
+        raise ValueError(f"Version string '{version_string}' did not match required pattern")
+
+    version_tuple = [int(x) for x in match.groups()]
+
+    # Look through the existing releases
+    existing = get_existing_release_tags()
+
+    # Assume that this is the highest release, unless told otherwise
+    highest_release = True
+
+    for release in existing:
+        if release == version_tuple:
+            raise ValueError(f"Duplicate release '{version_string}' exists!")
+
+        if release > version_tuple:
+            highest_release = False
+            print(f"Found newer release: {str(release)}")
+
+    return highest_release
+
+
+if __name__ == '__main__':
+
+    here = os.path.abspath(os.path.dirname(__file__))
+
+    # GITHUB_REF_TYPE may be either 'branch' or 'tag'
+    GITHUB_REF_TYPE = os.environ['GITHUB_REF_TYPE']
+
+    # GITHUB_REF may be either 'refs/heads/<branch>' or 'refs/heads/<tag>'
+    GITHUB_REF = os.environ['GITHUB_REF']
+
+    GITHUB_BASE_REF = os.environ['GITHUB_BASE_REF']
+
+    version_file = os.path.join(here, '..', 'InvenTree', 'InvenTree', 'version.py')
+
+    version = None
+
+    with open(version_file, 'r') as f:
+
+        text = f.read()
+
+        # Extract the InvenTree software version
+        results = re.findall(r'INVENTREE_SW_VERSION = "(.*)"', text)
+
+        if len(results) != 1:
+            print(f"Could not find INVENTREE_SW_VERSION in {version_file}")
+            sys.exit(1)
+
+        version = results[0]
+
+    print(f"InvenTree Version: '{version}'")
+
+    highest_release = check_version_number(version)
+
+    # Determine which docker tag we are going to use
+    docker_tags = None
+
+    if GITHUB_REF_TYPE == 'tag':
+        # GITHUB_REF should be of th eform /refs/heads/<tag>
+        version_tag = GITHUB_REF.split('/')[-1]
+        print(f"Checking requirements for tagged release - '{version_tag}':")
+
+        if version_tag != version:
+            print(f"Version number '{version}' does not match tag '{version_tag}'")
+            sys.exit
+
+        # TODO: Check if there is already a release with this tag!
+
+        if highest_release:
+            docker_tags = [version_tag, 'stable']
+        else:
+            docker_tags = [version_tag]
+
+    elif GITHUB_REF_TYPE == 'branch':
+        # Otherwise we know we are targetting the 'master' branch
+        print("Checking requirements for 'master' development branch:")
+
+        pattern = r"^\d+(\.\d+)+ dev$"
+        result = re.match(pattern, version)
+
+        if result is None:
+            print(f"Version number '{version}' does not match required pattern for development branch")
+            sys.exit(1)
+        else:
+            print(f"Version number '{version}' matches development branch")
+
+        docker_tags = ['latest']
+
+    else:
+        print("Unsupported branch / version combination:")
+        print(f"InvenTree Version: {version}")
+        print("GITHUB_REF_TYPE:", GITHUB_REF_TYPE)
+        print("GITHUB_BASE_REF:", GITHUB_BASE_REF)
+        print("GITHUB_REF:", GITHUB_REF)
+        sys.exit(1)
+
+    if docker_tags is None:
+        print("Docker tag could not be determined")
+        sys.exit(1)
+
+    print(f"Version check passed for '{version}'!")
+    print(f"Docker tags: '{docker_tags}'")
+
+    # Ref: https://getridbug.com/python/how-to-set-environment-variables-in-github-actions-using-python/
+    with open(os.getenv('GITHUB_ENV'), 'a') as env_file:
+
+        # Construct tag string
+        tags = ",".join([f"inventree/inventree:{tag}" for tag in docker_tags])
+
+        env_file.write(f"docker_tags={tags}\n")
+
+        if GITHUB_REF_TYPE == 'tag' and highest_release:
+            env_file.write("stable_release=true\n")