Addresses review comments adding a default limit value

charmcraft.yaml

@@ -142,8 +142,11 @@ config:
         revoking all previously issued certificates.
     certificate-limit:
       type: int
+      default: 99
       description: >
         Maximum number of certificates that can be issued to a single requirer.
+        Defaults to 99.
+        Use -1 for allowing an unlimited number of certificates.
 
 actions:
   get-ca-certificate:

src/charm.py

@@ -126,7 +126,7 @@ def _config_certificate_validity(self) -> timedelta | None:
         return validity
 
     @property
-    def _config_certificate_number_limit(self) -> int | None:
+    def _config_certificate_limit(self) -> int | None:
         """Return certificate number limit from the charm config."""
         value = self.model.config.get("certificate-limit")
         if not value or not isinstance(value, int):
@@ -420,7 +420,7 @@ def _clean_up_juju_secret(self, label: str):
     def _process_outstanding_certificate_requests(self) -> None:
         """Process outstanding certificate requests."""
         requests = self.tls_certificates.get_outstanding_certificate_requests()
-        if self._config_certificate_number_limit:
+        if self._config_certificate_limit and self._config_certificate_limit > -1:
             requests = self._limit_requests(requests)
         for request in requests:
             self._generate_self_signed_certificate(
@@ -436,7 +436,7 @@ def _limit_requests(
         counts = {}
         for request in requests:
             counts[request.relation_id] = counts.get(request.relation_id, 0) + 1
-            if counts[request.relation_id] <= self._config_certificate_number_limit:
+            if counts[request.relation_id] <= self._config_certificate_limit:
                 yield request
 
     def _invalid_configs(self) -> list[str]:

tests/unit/test_charm_configure.py

@@ -292,6 +292,7 @@ def test_given_outstanding_certificate_requests_when_config_changed_then_certifi
                 "ca-common-name": "example.com",
                 "certificate-validity": "100",
                 "root-ca-validity": "200",
+                "certificate-limit": -1,
             },
             leader=True,
             relations={tls_relation},