feat: Create CSP class

Author: jackylamhk

http_csp/csp.py

@@ -0,0 +1,56 @@
+from typing import Optional
+
+
+class CSP:
+    base_uri: list[str]
+    child_src: list[str]
+    connect_src: list[str]
+    default_src: list[str]
+    font_src: list[str]
+    form_action: list[str]
+    frame_ancestors: list[str]
+    frame_src: list[str]
+    img_src: list[str]
+    manifest_src: list[str]
+    media_src: list[str]
+    object_src: list[str]
+    report_sample: list[str]
+    report_to: list[str]
+    sandbox: list[str]
+    script_src: list[str]
+    script_src_attr: list[str]
+    script_src_elem: list[str]
+    strict_dynamic: list[str]
+    style_src: list[str]
+    style_src_attr: list[str]
+    style_src_elem: list[str]
+    unsafe_hashes: list[str]
+    upgrade_insecure_requests: list[str]
+    worker_src: list[str]
+
+    def __init__(self, policy: Optional[str] = None):
+        """
+        Initialize a CSP object from a Content Security Policy string.
+        """
+        if not policy:
+            return
+        policy = policy.strip().removesuffix(";")
+        policy_dict = {
+            p.split()[0].replace("-", "_"): p.split()[1:] for p in policy.split(";")
+        }
+        for key in policy_dict.keys():
+            if key not in self.__annotations__.keys():
+                raise ValueError(
+                    f'"{key.replace("_", "-")}" is not a valid CSP directive'
+                )
+        self.__dict__ = policy_dict
+
+    def generate(self) -> str:
+        """
+        Generate a Content Security Policy string.
+        """
+        policy = "; ".join(
+            [f'{k.replace("_", "-")} {(" ").join(v)}' for k, v in self.__dict__.items()]
+        ).strip()
+        policy += ";"
+        return policy