MVT: Generate metadata.json with copyright and timing information.

So the information can be exposed to the webmap's info dialog.

1 files changed, 59 insertions, 1 deletions

diff --git a/common.py b/common.py
index 0035160..0859ef0 100644
--- a/common.py
+++ b/common.py
@@ -19,7 +19,7 @@
 # pylint: disable=missing-module-docstring
 
 import os
-from os import path as os_path, curdir as os_curdir
+from os import path as os_path, curdir as os_curdir, pardir as os_pardir, sep as os_sep
 import sys
 from fnmatch import fnmatchcase
 from pathlib import Path, PosixPath
@@ -151,6 +151,64 @@ def parse_config(path : Optional[Path] = None,
 
     return config
 
+def _check_key_type(k : str, v : str, known_keys : list[type, tuple[set[str]]]) -> bool:
+    for t, ks in known_keys:
+        if k in ks and isinstance(v, t):
+            return True
+    return False
+
+def parse_config_dl(downloads) -> dict[str, dict[str, str|int]]:
+    """Parse and validate the "downloads" section from the configuration dictionary"""
+
+    if not isinstance(downloads, list):
+        raise BadConfiguration(f'Invalid download recipe: {downloads}')
+
+    known_keys = [
+        (str, {'path', 'url'}),
+        (int, {'max-age', 'max-size'}),
+    ]
+
+    destinations = {}
+    known_keys_set = {k for _,ks in known_keys for k in ks}
+    for dl in downloads:
+        if 'url' in dl:
+            dls = [dl]
+        elif 'basedir' in dl and 'baseurl' in dl and 'files' in dl and 'path' not in dl:
+            dls = []
+            for filename in dl['files']:
+                dl2 = {
+                    'path' : os_path.join(dl['basedir'], filename),
+                    'url' : dl['baseurl'] + filename
+                }
+                for k, v in dl.items():
+                    if k not in ('basedir', 'baseurl', 'files'):
+                        dl2[k] = v
+                dls.append(dl2)
+        else:
+            raise BadConfiguration(f'Invalid download recipe: {dl}')
+
+        for dl in dls:
+            path = dl.get('path', None)
+            if path is None or path in ('', os_curdir, os_pardir) or path.endswith(os_sep):
+                raise BadConfiguration(f'Invalid destination path "{path}"')
+            if path in destinations:
+                raise BadConfiguration(f'Duplicate download recipe for "{path}"')
+            dl2 = {}
+            for k, v in dl.items():
+                if k == 'path':
+                    continue
+                if k not in known_keys_set:
+                    logging.warning('Ignoring unknown setting "%s" in download recipe for "%s"',
+                                    k, path)
+                elif not _check_key_type(k, v, known_keys):
+                    logging.warning('Ignoring setting "%s" in download recipe for "%s"'
+                                    ' (invalid type)', k, path)
+                else:
+                    dl2[k] = v
+            destinations[path] = dl2
+
+    return destinations
+
 # pylint: disable-next=invalid-name
 def getSourcePathLockFileName(path : str) -> str:
     """Return the name of the lockfile associated with a source path."""