[Feature] Minimal IUCLID export (#338)

This is an initial implementation that creates a working minimal .i6z document.
It passes schema validation and can be imported into IUCLID.

Caveat:
IUCLID files target individual compounds.
Pathway is not actually covered by the format.

It can be added in either soil or water and soil OECD endpoints.
**I currently only implemented the soil endpoint for all data.**

This sort of works, and I can report all degradation products in a pathway (not a nice view, but we can report many transformation products and add a diagram attachment in the future).

Adding additional information is an absolute pain, as we need to explicitly map each type of information to the relevant OECD field.
I use the XSD scheme for validation, but unfortunately the IUCLID parser is not fully compliant and requires a specific order, etc.

The workflow is: finding the AI structure from the XSD scheme -> make the scheme validation pass -> upload to IUCLID to get obscure error messages -> guess what could be wrong -> repeat 💣

New specifications get released once per year, so we will have to update accordingly.
I believe that this should be a more expensive feature, as it requires significant effort to uphold.

Currently implemented for root compound only in SOIL:

- Soil Texture 2
- Soil Texture 1
- pH value
- Half-life per soil sample / scenario (mapped to disappearance; not sure about that).
- CEC
- Organic Matter (only Carbon)
- Moisture content
- Humidity

<img width="2123" alt="image.png" src="attachments/d29830e1-65ef-4136-8939-1825e0959c62">
<img width="2124" alt="image.png" src="attachments/ac9de2ac-bf68-4ba4-b40b-82f810a9de93">
<img width="2139" alt="image.png" src="attachments/5674c7e6-865e-420e-974a-6b825b331e6c">

Reviewed-on: enviPath/enviPy#338
Co-authored-by: Tobias O <tobias.olenyi@envipath.com>
Co-committed-by: Tobias O <tobias.olenyi@envipath.com>

tests/views/test_pathway_views.py

@@ -38,7 +38,7 @@ class PathwayViewTest(TestCase):
             },
         )
         self.assertEqual(response.status_code, 302)
-        pathway_url = response.url
+        pathway_url = response["Location"]
 
         pw = Pathway.objects.get(url=pathway_url)
         self.assertEqual(self.user1_default_package, pw.package)
@@ -81,7 +81,7 @@ class PathwayViewTest(TestCase):
             },
         )
         self.assertEqual(response.status_code, 302)
-        pathway_url = response.url
+        pathway_url = response["Location"]
 
         pw = Pathway.objects.get(url=pathway_url)
         self.assertEqual(self.package, pw.package)
@@ -128,7 +128,7 @@ class PathwayViewTest(TestCase):
         )
 
         self.assertEqual(response.status_code, 302)
-        pathway_url = response.url
+        pathway_url = response["Location"]
         pw = Pathway.objects.get(url=pathway_url)
 
         response = self.client.post(
@@ -166,3 +166,37 @@ class PathwayViewTest(TestCase):
 
         pw = Pathway.objects.get(url=pathway_url)
         self.assertEqual(len(pw.aliases), 0)
+
+    @override_settings(FLAGS={**s.FLAGS, "IUCLID_EXPORT": True})
+    def test_pathway_detail_shows_iuclid_export_action_when_enabled(self):
+        pathway = Pathway.create(self.package, "CCO", name="IUCLID Export Pathway")
+
+        response = self.client.get(
+            reverse(
+                "package pathway detail",
+                kwargs={
+                    "package_uuid": str(pathway.package.uuid),
+                    "pathway_uuid": str(pathway.uuid),
+                },
+            )
+        )
+
+        self.assertEqual(response.status_code, 200)
+        self.assertContains(response, f"/api/v1/pathway/{pathway.uuid}/export/iuclid")
+
+    @override_settings(FLAGS={**s.FLAGS, "IUCLID_EXPORT": False})
+    def test_pathway_detail_hides_iuclid_export_action_when_disabled(self):
+        pathway = Pathway.create(self.package, "CCO", name="IUCLID Export Pathway")
+
+        response = self.client.get(
+            reverse(
+                "package pathway detail",
+                kwargs={
+                    "package_uuid": str(pathway.package.uuid),
+                    "pathway_uuid": str(pathway.uuid),
+                },
+            )
+        )
+
+        self.assertEqual(response.status_code, 200)
+        self.assertNotContains(response, f"/api/v1/pathway/{pathway.uuid}/export/iuclid")