feat(email_scan): add Quora email module (#639)

* feat(email_scan): add Quora email module

* fix(email_scan): use Quora signup email validation

Author: kristoisberg

user_scanner/email_scan/community/quora.py

@@ -0,0 +1,49 @@
+import re
+
+from curl_cffi.requests.exceptions import RequestException
+
+from user_scanner.core.impersonate import impersonate_request_async
+from user_scanner.core.result import Result
+
+SHOW_URL = "https://www.quora.com"
+QUERY_NAME = "SignupEmailForm_validateEmail_Query"
+QUERY_HASH = "1db80096407be846d5581fe1b42b12fd05e0b40a5d3095ed40a0b4bd28f49fe7"
+
+
+async def validate_quora(email: str) -> Result:
+    """Quiet signup validation probe. It sends no email."""
+    try:
+        page = await impersonate_request_async(SHOW_URL, allow_redirects=True)
+        formkey = re.search(r'"formkey":\s*"([a-f0-9]+)"', page.text)
+        if page.status_code != 200 or not formkey:
+            return Result.error(
+                f"Could not load Quora login page: {page.status_code}",
+                url=SHOW_URL,
+            )
+
+        response = await impersonate_request_async(
+            f"{SHOW_URL}/graphql/gql_para_POST",
+            "POST",
+            params={"q": QUERY_NAME},
+            headers={"quora-formkey": formkey.group(1)},
+            json={
+                "queryName": QUERY_NAME,
+                "variables": {"email": email},
+                "extensions": {"hash": QUERY_HASH},
+            },
+        )
+        if response.status_code != 200:
+            return Result.error(
+                f"Unexpected Quora response: {response.status_code}",
+                url=SHOW_URL,
+            )
+
+        state = (response.json().get("data") or {}).get("validateEmail")
+        if state in {"IN_USE", "NOT_CONFIRMED"}:
+            confirmed = state == "IN_USE"
+            return Result.taken(url=SHOW_URL, extra={"email_confirmed": confirmed})
+        if state == "OK":
+            return Result.available(url=SHOW_URL)
+        return Result.error(f"Unexpected Quora signup state: {state}", url=SHOW_URL)
+    except (RequestException, ValueError, AttributeError) as exc:
+        return Result.error(exc, url=SHOW_URL)