Split repo generation functionality out of blenderpack.py

Moved repo.json generation to make_repo.py
Package/addon parsing is getting a bit messy, this can be
cleaned up when we have a clearer idea of what a package is.

For now just make it work.

make_repo.py

@@ -0,0 +1,162 @@
+#!/usr/bin/env python3
+
+from pathlib import Path
+import argparse
+import zipfile
+import ast
+import json
+import logging
+from utils import *
+
+log = logging.getLogger(__name__)
+
+REQUIRED_KEYS = set(['name', 'blender', 'version'])
+SCHEMA_VERSION = 1
+
+class BadAddon(Exception):
+    pass
+
+def iter_addons(path: Path) -> (Path, dict):
+    """
+    Generator, yields (path, bl_info) of blender addons in `path` (non recursive).
+    """
+    pass
+    # for item in addons_dir.iterdir():
+    #     base = item.name
+    #
+    #         yield (base, fname, '.zip')
+    #     else:
+    # yield (base, item.path, '.py') 
+
+def parse_blinfo(source: str) -> dict:
+    """Parse a python file and return its bl_info dict, if there is one (else return None)"""
+
+    try:
+        tree = ast.parse(source)
+    except SyntaxError as e:
+        raise BadAddon("Syntax error") from e
+
+    for body in tree.body:
+        if body.__class__ != ast.Assign:
+            continue
+        if len(body.targets) != 1:
+            continue
+        if getattr(body.targets[0], 'id', '') != 'bl_info':
+            continue
+
+        return ast.literal_eval(body.value)
+
+    raise BadAddon('No bl_info found')
+
+
+def extract_blinfo(item: Path) -> dict:
+    """
+    Extract bl_info dict from addon at path (can be single file, python package, or zip)
+    """
+
+    blinfo = None
+    addon_name = item.name
+    
+    if not item.exists():
+        raise FileNotFoundError("Cannot extract blinfo from '%s'; no such file or directory" % item)
+
+    if item.is_dir():
+        fname = item / '__init__.py'
+        try:
+            with fname.open("r") as f:
+                blinfo = parse_blinfo(f.read())
+        except FileNotFoundError as err:
+            # directory with no __init__.py: not an addon
+            raise BadAddon("Directory '%s' doesn't contain __init__.py; not a python package" % item) from err
+    
+    elif item.is_file():
+        try:
+            with zipfile.ZipFile(str(item), 'r') as z:
+                if len(z.namelist()) == 1:
+                    # zipfile with one item: just read that item
+                    blinfo = parse_blinfo(z.read(z.namelist()[0]))
+                else:
+                    # zipfile with multiple items: try all __init__.py files
+                    for fname in z.namelist():
+                        # TODO: zips with multiple bl_infos might be a problem,
+                        # not sure how such cases should be handled (if at all)
+                        if fname.endswith('__init__.py'):
+                            try:
+                                blinfo = parse_blinfo(z.read(fname))
+                                break
+                            except BadAddon:
+                                continue
+                    raise BadAddon("Zipfile '%s' doesn't contain any readable bl_info dict" % item)
+
+        except zipfile.BadZipFile:
+            # Assume file is 
+            with item.open() as f:
+                blinfo = parse_blinfo(f.read())
+
+    # This should not happen
+    if blinfo == None:
+        raise RuntimeError("Could not read addon '%s'" % addon_name)
+
+    return blinfo
+
+
+
+def make_repo(repopath: Path):
+    """Make repo.json for files in directory 'repopath'"""
+
+    repo_data = {}
+    package_data = []
+
+    if not repopath.is_dir():
+        raise FileNotFoundError(repopath)
+
+    for addon_path in repopath.iterdir():
+        package_datum = {}
+        addon = addon_path.name
+
+        try:
+            bl_info = extract_blinfo(addon_path)
+        except BadAddon as err:
+            log.warning('Could not extract bl_info from {}: {}'.format(addon_path, err))
+            continue
+
+        if not REQUIRED_KEYS.issubset(set(bl_info)):
+            log.warning(
+                    "Required key(s) '{}' not found in bl_info of '{}'".format(
+                        "', '".join(REQUIRED_KEYS.difference(set(bl_info))), addon)
+                    )
+
+        package_datum['bl_info'] = bl_info
+        package_datum['type'] = 'addon'
+        package_data.append(package_datum)
+
+    repo_data['packages'] = package_data
+
+    log.info("Repository generation successful")
+    cwd = Path.cwd()
+    dump_repo(cwd, repo_data)
+    log.info("repo.json written to %s" % cwd)
+
+
+def main():
+    parser = argparse.ArgumentParser(description='Generate a blender package repository from a directory of addons')
+
+    parser.add_argument('-v', '--verbose',
+            help="Increase verbosity (can be used multiple times)",
+            action="count",
+            default=0)
+    parser.add_argument('path',
+            type=Path,
+            nargs='?',
+            default=Path.cwd(),
+            help="Path to addon directory")
+
+    args = parser.parse_args()
+    log.level = args.verbose
+    logging.basicConfig(level=logging.INFO,
+            format='%(levelname)8s: %(message)s')
+
+    make_repo(args.path)
+
+if __name__ == '__main__':
+    main()