Tolerate Podman's response to docker context ls

In Spring Boot 3.x with Jackson 2, a null (or missing) value for
a primitive would be mapped to the primitive's default value. In
Jackson 3, the default behavior is to fail instead. This causes a
failure when trying to deserialize Podman's
`docker context ls response` as it is not in the expected format
and has no entry for `current` that's mapped to a boolean.

This commit disables FAIL_ON_NULL_FOR_PRIMITIVES to restore the
behavior that we had with Jackson 2 in Spring Boot 3.x.

Closes gh-47971

Author: wilkinsona

core/spring-boot-docker-compose/src/main/java/org/springframework/boot/docker/compose/core/DockerCliContextResponse.java

@@ -16,16 +16,18 @@
 
 package org.springframework.boot.docker.compose.core;
 
+import org.jspecify.annotations.Nullable;
+
 /**
  * Response from {@link DockerCliCommand.Context docker context}.
  *
  * @param name the name of the context
  * @param current if the context is the current one
- * @param dockerEndpoint the endpoint of the docker daemon
+ * @param dockerEndpoint the endpoint of the docker daemon, or {@code null} if not known
  * @author Moritz Halbritter
  * @author Andy Wilkinson
  * @author Phillip Webb
  */
-record DockerCliContextResponse(String name, boolean current, String dockerEndpoint) {
+record DockerCliContextResponse(String name, boolean current, @Nullable String dockerEndpoint) {
 
 }

core/spring-boot-docker-compose/src/main/java/org/springframework/boot/docker/compose/core/DockerJson.java

@@ -37,6 +37,7 @@ final class DockerJson {
 		.defaultLocale(Locale.ENGLISH)
 		.enable(MapperFeature.ACCEPT_CASE_INSENSITIVE_PROPERTIES)
 		.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
+		.disable(DeserializationFeature.FAIL_ON_NULL_FOR_PRIMITIVES)
 		.build();
 
 	private DockerJson() {

core/spring-boot-docker-compose/src/test/java/org/springframework/boot/docker/compose/core/DockerCliContextResponseTests.java

@@ -44,4 +44,13 @@ void deserializeJson() throws IOException {
 		assertThat(response).isEqualTo(expected);
 	}
 
+	@Test
+	void deserializePodmanJson() throws IOException {
+		String json = new ClassPathResource("docker-context-podman.json", getClass())
+			.getContentAsString(StandardCharsets.UTF_8);
+		DockerCliContextResponse response = DockerJson.deserialize(json, DockerCliContextResponse.class);
+		DockerCliContextResponse expected = new DockerCliContextResponse("podman-machine-default", false, null);
+		assertThat(response).isEqualTo(expected);
+	}
+
 }

core/spring-boot-docker-compose/src/test/resources/org/springframework/boot/docker/compose/core/docker-context-podman.json

@@ -0,0 +1,8 @@
+{
+    "Name": "podman-machine-default",
+    "URI": "ssh://core@127.0.0.1:55599/run/user/501/podman/podman.sock",
+    "Identity": "/Users/user/.local/share/containers/podman/machine/machine",
+    "IsMachine": true,
+    "Default": false,
+    "ReadWrite": true
+}