Render placeholders located in hyperlink URLs

docxtpl/template.py

@@ -377,6 +377,28 @@ def render_footnotes(
                     xml = self.render_xml_part(xml, part, context, jinja_env)
                     part._blob = xml.encode("utf-8")
 
+    def render_hyperlinks(
+        self, context: Dict[str, Any], jinja_env: Optional[Environment] = None
+    ) -> None:
+        """Render jinja placeholders in external hyperlink URL targets.
+
+        Hyperlink labels are stored in document XML and are already handled by
+        render_xml_part(), but their URLs are stored as external relationships
+        (e.g. word/_rels/document.xml.rels) and must be rendered separately.
+        """
+        for part in self.docx.part.package.parts:
+            for rel in part.rels.values():
+                if not rel.is_external or rel.reltype != REL_TYPE.HYPERLINK:
+                    continue
+                target = rel.target_ref
+                if "{{" not in target and "{%" not in target and "{#" not in target:
+                    continue
+                if jinja_env:
+                    template = jinja_env.from_string(target)
+                else:
+                    template = Template(target)
+                rel._target = template.render(context)
+
     def resolve_listing(self, xml):
 
         def resolve_text(run_properties, paragraph_properties, m):
@@ -511,6 +533,8 @@ def render(
 
         self.render_footnotes(context, jinja_env)
 
+        self.render_hyperlinks(context, jinja_env)
+
         # set rendered flag
         self.is_rendered = True
 
@@ -915,8 +939,15 @@ def get_undeclared_template_variables(
         else:
             env = Environment()
 
-        parse_content = env.parse(xml)
-        all_variables = meta.find_undeclared_variables(parse_content)
+        all_variables = meta.find_undeclared_variables(env.parse(xml))
+        for part in temp_doc.part.package.parts:
+            for rel in part.rels.values():
+                if not rel.is_external or rel.reltype != REL_TYPE.HYPERLINK:
+                    continue
+                target = rel.target_ref
+                if "{{" not in target and "{%" not in target and "{#" not in target:
+                    continue
+                all_variables |= meta.find_undeclared_variables(env.parse(target))
 
         # If context is provided, return only variables that are not in the context
         if context is not None:

tests/hyperlink.py

@@ -0,0 +1,26 @@
+# -*- coding: utf-8 -*-
+import re
+import zipfile
+
+from docxtpl import DocxTemplate
+
+tpl = DocxTemplate("templates/hyperlink_tpl.docx")
+context = {"foo": "https://example.com"}
+tpl.render(context)
+output_path = "output/hyperlink.docx"
+tpl.save(output_path)
+
+with zipfile.ZipFile(output_path) as docx:
+    rels = docx.read("word/_rels/document.xml.rels").decode()
+    document = docx.read("word/document.xml").decode()
+
+assert 'Target="https://example.com"' in rels, rels
+assert "{{ foo }}" not in rels, rels
+assert re.search(r"<w:t[^>]*>https://example.com</w:t>", document), document
+
+undeclared = DocxTemplate("templates/hyperlink_tpl.docx").get_undeclared_template_variables(
+    context=context
+)
+assert undeclared == set(), undeclared
+
+print("hyperlink test passed")