Include get_signing_certificate only if set.

Author: aarmam

example/src/main/java/eu/webeid/example/security/WebEidMobileAuthInitFilter.java

@@ -22,9 +22,12 @@
 
 package eu.webeid.example.security;
 
+import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectWriter;
+import com.fasterxml.jackson.databind.PropertyNamingStrategies;
+import com.fasterxml.jackson.databind.annotation.JsonNaming;
 import eu.webeid.example.config.WebEidMobileProperties;
 import eu.webeid.security.challenge.ChallengeNonceGenerator;
 import jakarta.servlet.FilterChain;
@@ -71,10 +74,9 @@ protected void doFilterInternal(@NonNull HttpServletRequest request,
         String loginUri = ServletUriComponentsBuilder.fromCurrentContextPath()
             .path(mobileLoginPath).build().toUriString();
 
-        boolean getSigningCertificate = webEidMobileProperties.requestSigningCert();
-
         String payloadJson = OBJECT_WRITER.writeValueAsString(
-            new AuthPayload(challenge.getBase64EncodedNonce(), loginUri, getSigningCertificate)
+            new AuthPayload(challenge.getBase64EncodedNonce(), loginUri,
+                webEidMobileProperties.requestSigningCert() ? Boolean.TRUE : null)
         );
         String encoded = Base64.getEncoder().encodeToString(payloadJson.getBytes(StandardCharsets.UTF_8));
         String eidAuthUri = "web-eid-mobile://auth#" + encoded;
@@ -83,12 +85,15 @@ protected void doFilterInternal(@NonNull HttpServletRequest request,
         OBJECT_WRITER.writeValue(response.getWriter(), new AuthUri(eidAuthUri));
     }
 
+    @JsonNaming(PropertyNamingStrategies.SnakeCaseStrategy.class)
+    @JsonInclude(JsonInclude.Include.NON_NULL)
     record AuthPayload(
         String challenge,
-        @JsonProperty("login_uri") String loginUri,
-        @JsonProperty("get_signing_certificate") boolean getSigningCertificate) {
+        String loginUri,
+        Boolean getSigningCertificate) {
     }
 
+    @JsonNaming(PropertyNamingStrategies.SnakeCaseStrategy.class)
     record AuthUri(@JsonProperty("auth_uri") String authUri) {
     }
 }