Automatically get version number from project file

build.py

@@ -2,11 +2,12 @@
 import subprocess
 import argparse
 from itertools import chain
+import re
 
 dockercmd = 'docker'
 
 parser = argparse.ArgumentParser(description='Create custom recumock images.')
-parser.add_argument('tags', metavar='TAG', nargs='+', help='Version tags to build.')
+parser.add_argument('tags', metavar='TAG', nargs='*', help='Version tags to build.')
 
 args = parser.parse_args()
 
@@ -25,6 +26,19 @@ def build(images, directory, platforms, build_args = None):
     print(' '.join(command))
     subprocess.run(command, check=True)
 
+def version_from_project():
+    with open(r'MinecraftDiscordBot\MinecraftDiscordBot.csproj', 'r') as f:
+        project = f.read()
+
+    regex = r"<Version>\s*([^<]*?)\s*<\/Version>"
+    matches = re.search(regex, project, re.IGNORECASE)
+    if not matches:
+        raise Exception("Could not read version from project file!")
+    return matches.group(1)
+
+if len(args.tags) == 0:
+    args.tags.append(version_from_project())
+
 for version in args.tags:
     parts = version.split('.')
     tags = list('.'.join(parts[:i]) for i in range(1, len(parts) + 1))