Fix mutating global RestClient and WebClient builders (#3020)

Since the builders for HTTP clients are mutable and shared, they should
only be configured with globally applicable settings. The current use
leaks specific details into other usages and affects newly instantiated
clients. This PR applies the clone() method right before mutation
happens as it probably is the strategy that avoids multiple unnecessary
copies.

feat: improve RestClient and WebClient instantiation and configuration across AI modules

- Ensure RestClient.Builder and WebClient.Builder are properly cloned before setting base URLs and headers in Mistral, OpenAI, and Ollama API classes to prevent side effects.
- Add WebClientAutoConfiguration to auto-configuration classes for Anthropic and Mistral AI modules.
- Update Mistral AI auto-configuration to inject and use WebClient.Builder.
- Clean up test and annotation usage (remove unnecessary @nullable, fix test builder usage in AnthropicApiIT).
- Improve consistency and reliability of HTTP client configuration across model integrations.

Signed-off-by: Dariusz Jędrzejczyk <[email protected]>
Signed-off-by: Christian Tzolov <[email protected]>
Co-authored-by: Christian Tzolov <[email protected]>

Author: chemicL

auto-configurations/models/spring-ai-autoconfigure-model-anthropic/src/main/java/org/springframework/ai/model/anthropic/autoconfigure/AnthropicChatAutoConfiguration.java

@@ -52,7 +52,7 @@
  * @since 1.0.0
  */
 @AutoConfiguration(after = { RestClientAutoConfiguration.class, SpringAiRetryAutoConfiguration.class,
-		ToolCallingAutoConfiguration.class })
+		ToolCallingAutoConfiguration.class, WebClientAutoConfiguration.class })
 @EnableConfigurationProperties({ AnthropicChatProperties.class, AnthropicConnectionProperties.class })
 @ConditionalOnClass(AnthropicApi.class)
 @ConditionalOnProperty(name = SpringAIModelProperties.CHAT_MODEL, havingValue = SpringAIModels.ANTHROPIC,

auto-configurations/models/spring-ai-autoconfigure-model-mistral-ai/src/main/java/org/springframework/ai/model/mistralai/autoconfigure/MistralAiChatAutoConfiguration.java

@@ -35,13 +35,15 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.autoconfigure.web.client.RestClientAutoConfiguration;
+import org.springframework.boot.autoconfigure.web.reactive.function.client.WebClientAutoConfiguration;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.retry.support.RetryTemplate;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 import org.springframework.web.client.ResponseErrorHandler;
 import org.springframework.web.client.RestClient;
+import org.springframework.web.reactive.function.client.WebClient;
 
 /**
  * Chat {@link AutoConfiguration Auto-configuration} for Mistral AI.
@@ -52,28 +54,30 @@
  * @author Ilayaperumal Gopinathan
  * @since 0.8.1
  */
-@AutoConfiguration(after = { RestClientAutoConfiguration.class, SpringAiRetryAutoConfiguration.class,
-		ToolCallingAutoConfiguration.class })
+@AutoConfiguration(after = { RestClientAutoConfiguration.class, WebClientAutoConfiguration.class,
+		SpringAiRetryAutoConfiguration.class, ToolCallingAutoConfiguration.class })
 @EnableConfigurationProperties({ MistralAiCommonProperties.class, MistralAiChatProperties.class })
 @ConditionalOnProperty(name = SpringAIModelProperties.CHAT_MODEL, havingValue = SpringAIModels.MISTRAL,
 		matchIfMissing = true)
 @ConditionalOnClass(MistralAiApi.class)
 @ImportAutoConfiguration(classes = { SpringAiRetryAutoConfiguration.class, RestClientAutoConfiguration.class,
-		ToolCallingAutoConfiguration.class })
+		WebClientAutoConfiguration.class, ToolCallingAutoConfiguration.class })
 public class MistralAiChatAutoConfiguration {
 
 	@Bean
 	@ConditionalOnMissingBean
 	public MistralAiChatModel mistralAiChatModel(MistralAiCommonProperties commonProperties,
 			MistralAiChatProperties chatProperties, ObjectProvider<RestClient.Builder> restClientBuilderProvider,
-			ToolCallingManager toolCallingManager, RetryTemplate retryTemplate,
-			ResponseErrorHandler responseErrorHandler, ObjectProvider<ObservationRegistry> observationRegistry,
+			ObjectProvider<WebClient.Builder> webClientBuilderProvider, ToolCallingManager toolCallingManager,
+			RetryTemplate retryTemplate, ResponseErrorHandler responseErrorHandler,
+			ObjectProvider<ObservationRegistry> observationRegistry,
 			ObjectProvider<ChatModelObservationConvention> observationConvention,
 			ObjectProvider<ToolExecutionEligibilityPredicate> mistralAiToolExecutionEligibilityPredicate) {
 
 		var mistralAiApi = mistralAiApi(chatProperties.getApiKey(), commonProperties.getApiKey(),
 				chatProperties.getBaseUrl(), commonProperties.getBaseUrl(),
-				restClientBuilderProvider.getIfAvailable(RestClient::builder), responseErrorHandler);
+				restClientBuilderProvider.getIfAvailable(RestClient::builder),
+				webClientBuilderProvider.getIfAvailable(WebClient::builder), responseErrorHandler);
 
 		var chatModel = MistralAiChatModel.builder()
 			.mistralAiApi(mistralAiApi)
@@ -91,15 +95,17 @@ public MistralAiChatModel mistralAiChatModel(MistralAiCommonProperties commonPro
 	}
 
 	private MistralAiApi mistralAiApi(String apiKey, String commonApiKey, String baseUrl, String commonBaseUrl,
-			RestClient.Builder restClientBuilder, ResponseErrorHandler responseErrorHandler) {
+			RestClient.Builder restClientBuilder, WebClient.Builder webClientBuilder,
+			ResponseErrorHandler responseErrorHandler) {
 
 		var resolvedApiKey = StringUtils.hasText(apiKey) ? apiKey : commonApiKey;
 		var resoledBaseUrl = StringUtils.hasText(baseUrl) ? baseUrl : commonBaseUrl;
 
 		Assert.hasText(resolvedApiKey, "Mistral API key must be set");
 		Assert.hasText(resoledBaseUrl, "Mistral base URL must be set");
 
-		return new MistralAiApi(resoledBaseUrl, resolvedApiKey, restClientBuilder, responseErrorHandler);
+		return new MistralAiApi(resoledBaseUrl, resolvedApiKey, restClientBuilder, webClientBuilder,
+				responseErrorHandler);
 	}
 
 }

models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/AnthropicApi.java

@@ -119,12 +119,14 @@ private AnthropicApi(String baseUrl, String completionsPath, String anthropicApi
 
 		this.completionsPath = completionsPath;
 
-		this.restClient = restClientBuilder.baseUrl(baseUrl)
+		this.restClient = restClientBuilder.clone()
+			.baseUrl(baseUrl)
 			.defaultHeaders(jsonContentHeaders)
 			.defaultStatusHandler(responseErrorHandler)
 			.build();
 
-		this.webClient = webClientBuilder.baseUrl(baseUrl)
+		this.webClient = webClientBuilder.clone()
+			.baseUrl(baseUrl)
 			.defaultHeaders(jsonContentHeaders)
 			.defaultStatusHandler(HttpStatusCode::isError,
 					resp -> resp.bodyToMono(String.class)

models/spring-ai-anthropic/src/test/java/org/springframework/ai/anthropic/api/AnthropicApiIT.java

@@ -110,7 +110,7 @@ void chatCompletionStream() {
 	void chatCompletionStreamError() {
 		AnthropicMessage chatCompletionMessage = new AnthropicMessage(List.of(new ContentBlock("Tell me a Joke?")),
 				Role.USER);
-		AnthropicApi api = AnthropicApi.builder().baseUrl("FAKE_KEY_FOR_ERROR_RESPONSE").build();
+		AnthropicApi api = AnthropicApi.builder().apiKey("FAKE_KEY_FOR_ERROR_RESPONSE").build();
 
 		Flux<ChatCompletionResponse> response = api.chatCompletionStream(new ChatCompletionRequest(
 				AnthropicApi.ChatModel.CLAUDE_3_OPUS.getValue(), List.of(chatCompletionMessage), null, 100, 0.8, true));

models/spring-ai-minimax/src/main/java/org/springframework/ai/minimax/api/MiniMaxApi.java

@@ -115,7 +115,7 @@ public MiniMaxApi(String baseUrl, String miniMaxToken, RestClient.Builder restCl
 				.defaultStatusHandler(responseErrorHandler)
 				.build();
 
-		this.webClient = WebClient.builder()
+		this.webClient = WebClient.builder() // FIXME: use a bean instead
 				.baseUrl(baseUrl)
 				.defaultHeaders(authHeaders)
 				.build();

models/spring-ai-mistral-ai/src/main/java/org/springframework/ai/mistralai/api/MistralAiApi.java

@@ -101,18 +101,31 @@ public MistralAiApi(String baseUrl, String mistralAiApiKey) {
 	 */
 	public MistralAiApi(String baseUrl, String mistralAiApiKey, RestClient.Builder restClientBuilder,
 			ResponseErrorHandler responseErrorHandler) {
+		this(baseUrl, mistralAiApiKey, restClientBuilder, WebClient.builder(), responseErrorHandler);
+	}
+
+	/**
+	 * Create a new client api.
+	 * @param baseUrl api base URL.
+	 * @param mistralAiApiKey Mistral api Key.
+	 * @param restClientBuilder RestClient builder.
+	 * @param responseErrorHandler Response error handler.
+	 */
+	public MistralAiApi(String baseUrl, String mistralAiApiKey, RestClient.Builder restClientBuilder,
+			WebClient.Builder webClientBuilder, ResponseErrorHandler responseErrorHandler) {
 
 		Consumer<HttpHeaders> jsonContentHeaders = headers -> {
 			headers.setBearerAuth(mistralAiApiKey);
 			headers.setContentType(MediaType.APPLICATION_JSON);
 		};
 
-		this.restClient = restClientBuilder.baseUrl(baseUrl)
+		this.restClient = restClientBuilder.clone()
+			.baseUrl(baseUrl)
 			.defaultHeaders(jsonContentHeaders)
 			.defaultStatusHandler(responseErrorHandler)
 			.build();
 
-		this.webClient = WebClient.builder().baseUrl(baseUrl).defaultHeaders(jsonContentHeaders).build();
+		this.webClient = webClientBuilder.clone().baseUrl(baseUrl).defaultHeaders(jsonContentHeaders).build();
 	}
 
 	/**

models/spring-ai-ollama/src/main/java/org/springframework/ai/ollama/api/OllamaApi.java

@@ -79,12 +79,15 @@ private OllamaApi(String baseUrl, RestClient.Builder restClientBuilder, WebClien
 			headers.setAccept(List.of(MediaType.APPLICATION_JSON));
 		};
 
-		this.restClient = restClientBuilder.baseUrl(baseUrl)
+		this.restClient = restClientBuilder
+				.clone()
+				.baseUrl(baseUrl)
 				.defaultHeaders(defaultHeaders)
 				.defaultStatusHandler(responseErrorHandler)
 				.build();
 
 		this.webClient = webClientBuilder
+				.clone()
 				.baseUrl(baseUrl)
 				.defaultHeaders(defaultHeaders)
 				.build();

models/spring-ai-openai/src/main/java/org/springframework/ai/openai/api/OpenAiApi.java

@@ -115,12 +115,13 @@ public OpenAiApi(String baseUrl, ApiKey apiKey, MultiValueMap<String, String> he
 			h.setContentType(MediaType.APPLICATION_JSON);
 			h.addAll(headers);
 		};
-		this.restClient = restClientBuilder.baseUrl(baseUrl)
+		this.restClient = restClientBuilder.clone()
+			.baseUrl(baseUrl)
 			.defaultHeaders(finalHeaders)
 			.defaultStatusHandler(responseErrorHandler)
 			.build();
 
-		this.webClient = webClientBuilder
+		this.webClient = webClientBuilder.clone()
 			.baseUrl(baseUrl)
 			.defaultHeaders(finalHeaders)
 			.build(); // @formatter:on

models/spring-ai-openai/src/main/java/org/springframework/ai/openai/api/OpenAiAudioApi.java

@@ -77,12 +77,13 @@ public OpenAiAudioApi(String baseUrl, ApiKey apiKey, MultiValueMap<String, Strin
 			// h.setContentType(MediaType.APPLICATION_JSON);
 		};
 
-		this.restClient = restClientBuilder.baseUrl(baseUrl)
+		this.restClient = restClientBuilder.clone()
+			.baseUrl(baseUrl)
 			.defaultHeaders(authHeaders)
 			.defaultStatusHandler(responseErrorHandler)
 			.build();
 
-		this.webClient = webClientBuilder.baseUrl(baseUrl).defaultHeaders(authHeaders).build();
+		this.webClient = webClientBuilder.clone().baseUrl(baseUrl).defaultHeaders(authHeaders).build();
 	}
 
 	public static Builder builder() {

models/spring-ai-zhipuai/src/main/java/org/springframework/ai/zhipuai/api/ZhiPuAiApi.java

@@ -116,7 +116,7 @@ public ZhiPuAiApi(String baseUrl, String zhiPuAiToken, RestClient.Builder restCl
 				.defaultStatusHandler(responseErrorHandler)
 				.build();
 
-		this.webClient = WebClient.builder()
+		this.webClient = WebClient.builder() // FIXME: use a builder instead
 				.baseUrl(baseUrl)
 				.defaultHeaders(authHeaders)
 				.build();