Fixes DB Timestamp on Return

As pointed out by @ks129, fetching the responses would cause an error in
 the timestamp, as the validation was returning the current time at
 fetching, instead of the stored value.

Signed-off-by: Hassan Abouelela <[email protected]>

3 files changed, 21 insertions, 11 deletions

diff --git a/SCHEMA.md b/SCHEMA.md
index b37ed1d..59b6c33 100644
--- a/SCHEMA.md
+++ b/SCHEMA.md
@@ -127,13 +127,14 @@ Textareas require no additional configuration.
 
 ## Form response
 
-| Field      | Type                                                 | Description                                                                 |
-| ---------- | ---------------------------------------------------- | --------------------------------------------------------------------------- |
-| `_id`/`id` | MongoDB ObjectID                                     | Random identifier used for the response                                     |
-| `user`     | Optional [user details object](#user-details-object) | An object describing the user that submitted if the form is not anonymous   |
-| `antispam` | Optional [anti spam object](#anti-spam-object)       | An object containing information about the anti-spam on the form submission |
-| `response` | Object                                               | Object containing question IDs mapping to the users answer                  |
-| `form_id`  | String                                               | ID of the form that the user is submitting to                               |
+| Field       | Type                                                 | Description                                                                 |
+| ----------- | ---------------------------------------------------- | --------------------------------------------------------------------------- |
+| `_id`/`id`  | MongoDB ObjectID                                     | Random identifier used for the response                                     |
+| `user`      | Optional [user details object](#user-details-object) | An object describing the user that submitted if the form is not anonymous   |
+| `antispam`  | Optional [anti spam object](#anti-spam-object)       | An object containing information about the anti-spam on the form submission |
+| `response`  | Object                                               | Object containing question IDs mapping to the users answer                  |
+| `form_id`   | String                                               | ID of the form that the user is submitting to                               |
+| `timestamp` | String                                               | ISO formatted string of submission time.                                    |
 
 ### User details object
 
diff --git a/backend/models/form_response.py b/backend/models/form_response.py
index b6570e5..8a4da28 100644
--- a/backend/models/form_response.py
+++ b/backend/models/form_response.py
@@ -15,11 +15,18 @@ class FormResponse(BaseModel):
     antispam: t.Optional[AntiSpam]
     response: dict[str, t.Any]
     form_id: str
-    timestamp: str = datetime.datetime.now(tz=datetime.timezone.utc).isoformat()
+    timestamp: str
 
-    @validator("timestamp")
-    def set_timestamp(cls, _: str) -> str:
-        return datetime.datetime.now(tz=datetime.timezone.utc).isoformat()
+    @validator("timestamp", pre=True)
+    def set_timestamp(cls, iso_string: str) -> str:
+        if iso_string is None:
+            return datetime.datetime.now(tz=datetime.timezone.utc).isoformat()
+
+        elif not isinstance(iso_string, str):
+            raise ValueError("Submission timestamp must be a string.")
+
+        # Convert to datetime and back to ensure string is valid
+        return datetime.datetime.fromisoformat(iso_string).isoformat()
 
     class Config:
         allow_population_by_field_name = True
diff --git a/backend/routes/forms/submit.py b/backend/routes/forms/submit.py
index 3ecbda0..48ae4f6 100644
--- a/backend/routes/forms/submit.py
+++ b/backend/routes/forms/submit.py
@@ -34,6 +34,8 @@ class SubmitForm(Route):
     async def post(self, request: Request) -> JSONResponse:
         data = await request.json()
 
+        data["timestamp"] = None
+
         if form := await request.state.db.forms.find_one(
             {"_id": request.path_params["form_id"], "features": "OPEN"}
         ):