implement dotenv loading for allowed domains

.gitignore

@@ -673,3 +673,5 @@ fabric.properties
 ## ENVIRONMENT
 
 .env
+lvenv
+wvenv 

README.md

@@ -1,3 +1,10 @@
 # sanigi-html
 
 sanigi-html (esperanto for sanitize html) is a python tool which takes in HTML and sanitzies it for use with student webspaces
+
+.env spec:
+
+```env
+ALLOWED_DOMAINS_IMG=images.example.org,cdn.example.com
+ALLOWED_DOMAINS_LINK=example.com
+```

TODO.md

@@ -23,7 +23,7 @@ NOTE: That things which are in italic text are already implemented!
     - *img*
     - *link href*
 - *[x] add custom attribute filter function*
-- [] load dotenv (chore for profiles.py) ; do this someday when implementing JSON configs. Or dotenv stuff : PRIO:HIGH
+- *[x] load dotenv (chore for profiles.py) ; do this someday when implementing JSON configs. Or dotenv stuff : PRIO:HIGH*
 ---
 
 ### Expland strict mode:

src/profiles.py

@@ -4,10 +4,14 @@
 #
 #   presets for sanitization of HTML
 #
-import re
-from dotenv import dotenv_values
+
+import os
+from dotenv import load_dotenv 
 from urllib.parse import urlparse
 
+# loadenv init
+load_dotenv()
+
 def is_safe_url(url : str, allowed_domain=None, allow_relative : bool = True) -> bool:
     """
     Determine wether or not a URL is safe or not.
@@ -48,6 +52,21 @@ def create_url_filter(allowed_attrs, allowed_domains=None, allow_relative=True):
         return value
     return filter_func
 
+def get_domains(variable):
+    value = os.getenv(variable, "")
+    return [
+        # return a list of domains, and split by comma
+        d.strip() for d in value.split(",") if d.strip()
+    ]
+
+# Setup any .env variables for python to use
+
+allow_relative = os.getenv("ALLOW_RELATIVE_URLS", "true").lower() == "true"
+
+allowed_domains_default = get_domains("ALLOWED_DOMAINS")
+allowed_domains_img = get_domains("ALLOWED_DOMAINS_IMG") or allowed_domains_default
+allowed_domains_link = get_domains("ALLOWED_DOMAINS_LINK") or allowed_domains_default
+
 STRICT = {
     "tags" : [
         "p", "b", "i", "u", "em", "strong",
@@ -56,10 +75,21 @@ STRICT = {
         "h1", "h2", "h3", "h4", "h5", "h6"
     ],
     "attributes": {
-        # TODO: add loading dotenv variables
-        "a": create_url_filter(["href"], allowed_domains=[], allow_relative=True),
-        "img" : create_url_filter(["src", "alt"], allowed_domains=[], allow_relative=True),
-        "link" : create_url_filter(["href"], allowed_domains=[], allow_relative=True),
+        "a": create_url_filter(
+            ["href"],
+            allowed_domains=allowed_domains_link,
+            allow_relative=allow_relative
+        ),
+        "img": create_url_filter(
+            ["src", "alt"],
+            allowed_domains=allowed_domains_img,
+            allow_relative=allow_relative
+        ),
+        "link": create_url_filter(
+            ["href"],
+            allowed_domains=allowed_domains_default,
+            allow_relative=allow_relative
+        ),
     },
     "protocols": [],
     "strip": True,