Encode JSON string in Pulsar auth params

The values in the `spring.pulsar.client.authentication.param`
config props map are not currently JSON encoded. For simple
values this is fine. However, some custom auth modules may
require more complex parameter values that may contain special
characters that results in invalid JSON. This commmit encodes
the parameter values using a very simple hand-rolled escape
function.

See gh-40493

Author: onobc

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/pulsar/PulsarPropertiesMapper.java

@@ -89,14 +89,25 @@ private String getAuthenticationParamsJson(Map<String, String> params) {
 		try {
 			return sortedParams.entrySet()
 				.stream()
-				.map((entry) -> "\"%s\":\"%s\"".formatted(entry.getKey(), entry.getValue()))
+				.map((entry) -> "\"%s\":\"%s\"".formatted(entry.getKey(), escapeJson(entry.getValue())))
 				.collect(Collectors.joining(",", "{", "}"));
 		}
 		catch (Exception ex) {
 			throw new IllegalStateException("Could not convert auth parameters to encoded string", ex);
 		}
 	}
 
+	private String escapeJson(String raw) {
+		return raw.replace("\\", "\\\\")
+			.replace("\"", "\\\"")
+			.replace("/", "\\/")
+			.replace("\b", "\\b")
+			.replace("\t", "\\t")
+			.replace("\n", "\\n")
+			.replace("\f", "\\f")
+			.replace("\r", "\\r");
+	}
+
 	<T> void customizeProducerBuilder(ProducerBuilder<T> producerBuilder) {
 		PulsarProperties.Producer properties = this.properties.getProducer();
 		PropertyMapper map = PropertyMapper.get().alwaysApplyingWhenNonNull();

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/pulsar/PulsarPropertiesMapperTests.java

@@ -72,8 +72,10 @@ void customizeClientBuilderWhenHasNoAuthentication() {
 	@Test
 	void customizeClientBuilderWhenHasAuthentication() throws UnsupportedAuthenticationException {
 		PulsarProperties properties = new PulsarProperties();
-		Map<String, String> params = Map.of("param", "name");
-		String authParamString = "{\"param\":\"name\"}";
+		Map<String, String> params = Map.of("simpleParam", "foo", "complexParam",
+				"{\n\t\"k1\" : \"v1\",\n\t\"k2\":\"v2\"\n}");
+		String authParamString = "{\"complexParam\":\"{\\n\\t\\\"k1\\\" : \\\"v1\\\",\\n\\t\\\"k2\\\":\\\"v2\\\"\\n}\""
+				+ ",\"simpleParam\":\"foo\"}";
 		properties.getClient().getAuthentication().setPluginClassName("myclass");
 		properties.getClient().getAuthentication().setParam(params);
 		ClientBuilder builder = mock(ClientBuilder.class);
@@ -112,8 +114,10 @@ void customizeAdminBuilderWhenHasNoAuthentication() {
 	@Test
 	void customizeAdminBuilderWhenHasAuthentication() throws UnsupportedAuthenticationException {
 		PulsarProperties properties = new PulsarProperties();
-		Map<String, String> params = Map.of("param", "name");
-		String authParamString = "{\"param\":\"name\"}";
+		Map<String, String> params = Map.of("simpleParam", "foo", "complexParam",
+				"{\n\t\"k1\" : \"v1\",\n\t\"k2\":\"v2\"\n}");
+		String authParamString = "{\"complexParam\":\"{\\n\\t\\\"k1\\\" : \\\"v1\\\",\\n\\t\\\"k2\\\":\\\"v2\\\"\\n}\""
+				+ ",\"simpleParam\":\"foo\"}";
 		properties.getAdmin().getAuthentication().setPluginClassName("myclass");
 		properties.getAdmin().getAuthentication().setParam(params);
 		PulsarAdminBuilder builder = mock(PulsarAdminBuilder.class);