PROD-2486 Add custom_request_field to FidesMeta

CHANGELOG.md

@@ -15,7 +15,7 @@ The types of changes are:
 - `Security` in case of vulnerabilities.
 
 ## [Unreleased](https://github.com/ethyca/fideslang/compare/3.0.2...main)
-
+- Add custom_request_field to FidesMeta [#13](https://github.com/ethyca/fideslang/pull/13)
 
 ## [3.0.2](https://github.com/ethyca/fideslang/compare/3.0.1...3.0.2)
 

src/fideslang/models.py

@@ -402,6 +402,10 @@ class FidesMeta(BaseModel):
         default=None,
         description="Optionally specify if a field is read-only, meaning it can't be updated or deleted.",
     )
+    custom_request_field: Optional[str] = Field(
+        default=None,
+        description="Optionally specify that a field may be used as a custom request field in DSRs. The value is the name of the field in the DSR.",
+    )
 
     @field_validator("data_type")
     @classmethod

tests/fideslang/test_validation.py

@@ -625,6 +625,26 @@ def test_specify_fides_meta_directly(self):
             read_only=None,
         )
 
+    def test_specify_fides_meta_with_custom_request_field(self):
+        """fidesops_meta copied to fides_meta"""
+        field = DatasetField(
+            name="test_field",
+            fides_meta={"custom_request_field": "site_id", "primary_key": False},
+            fields=[],
+        )
+
+        assert not hasattr(field, "fidesops_meta")
+        assert field.fides_meta == FidesMeta(
+            references=None,
+            identity=None,
+            primary_key=False,
+            data_type=None,
+            length=None,
+            return_all_elements=None,
+            read_only=None,
+            custom_request_field="site_id"
+        )
+
     def test_specify_both_fidesops_meta_and_fides_meta(self):
         """fidesops_meta copied to fides_meta - fides_meta field takes priority"""
         field = DatasetField(