Add class Config

Signed-off-by: Jan Lindemann <jan@janware.com>

tools/python/jwutils/Config.py

@@ -0,0 +1,104 @@
+# -*- coding: utf-8 -*-
+
+import os
+import re
+import glob
+import sys
+from pathlib import Path, PosixPath
+from typing import Optional, Dict, cast
+
+from jwutils import stree
+from .stree.StringTree import StringTree
+from .log import *
+
+class Config(): # export
+
+    def __init__(self, search_dirs: Optional[list[str]]=None, glob_paths: Optional[list[str]]=None,
+                 defaults: Dict[str, str]=None, tree: Optional[StringTree]=None, parent=None,
+                 root_section=None) -> None:
+
+        def __is_abs(path):
+            if path is None:
+                return False
+            if len(path) == 0:
+                return False
+            if path[0] != '/':
+                return False
+            return True
+
+        self.__parent = parent
+        exe = Path(os.path.basename(sys.argv[0])).stem
+        if glob_paths is None:
+            glob_paths = [f'.{exe}', f'{exe}.conf']
+        if search_dirs is None:
+            env_key = re.sub('[-.]', '_', exe)
+            search_dirs = os.getenv(env_key)
+        self.__conf = tree if tree else StringTree("", "")
+        for path in glob_paths:
+            dirs = search_dirs
+            if dirs is None:
+                dirs = [''] if __is_abs(path) else [ str(Path.home()), str(Path.cwd()) ]
+            for d in dirs:
+                g = d + '/' + path
+                slog(DEBUG, 'Looking for config "{}"'.format(g))
+                for f in glob.glob(g):
+                    slog(DEBUG, 'Reading config "{}"'.format(f))
+                    paths_buf = []
+                    tree = stree.read(f, paths_buf=paths_buf)
+                    assert(len(paths_buf))
+                    for p in paths_buf:
+                        st = os.stat(p)
+                        if st.st_mode & 0o0077:
+                            for item in tree.child_list():
+                                if item.content is None:
+                                    continue
+                                if not re.search('password|secret', cast(str, item.content), flags=re.IGNORECASE):
+                                    continue
+                                msg = "Config files define secret, but at least one has file permissions open for group or world"
+                                slog(ERR, f'{msg}:')
+                                for pp in paths_buf:
+                                    slog(ERR, f'  {((os.stat(p).st_mode) & 0o7777):o} {pp}')
+                                raise Exception(msg)
+                    tree.dump(DEBUG, f)
+                    self.__conf.add("", tree)
+
+        if root_section is not None:
+            self.__conf = self.__conf.get(root_section)
+            if self.__conf is None: 
+                self.__conf = StringTree("", "")
+
+        if defaults is not None:
+            for key, val in defaults.items():
+                if self.__conf.get(key) is None:
+                    self.__conf.set(key, val)
+
+        self.__conf.dump(DEBUG, "superposed configuration")
+
+    def __getitem__(self, key: str) -> Optional[str]:
+        return self.get(key)
+
+    @property
+    def parent(self):
+        return self.__parent
+
+    def set(self, key: str, val):
+        self.__conf[key] = val
+
+    def get(self, key: str, default = None) -> Optional[str]:
+        item = self.__conf.get(key)
+        if item:
+            return item.value()
+        return default
+
+    # This is an alias for get()
+    def value(self, key: str, default = None) -> Optional[str]:
+        return self.get(key, default)
+
+    def branch(self, path: str) -> Optional[StringTree]:
+        if self.__conf:
+            return Config(tree=self.__conf.get(path), parent=self)
+        return None
+
+    def dump(self, prio: int, *args, **kwargs) -> None:
+        caller = get_caller_pos(1, kwargs)
+        self.__conf.dump(prio, caller=caller, *args, **kwargs)