feat(observability): Refactor content observation mechanism to support both logging and tracing

This commit refactors the content observation mechanism by adding support for trace recording without altering the original logging functionality. The motivation for this change is to ensure complete context availability in scenarios such as integration with Langfuse, which is essential for proper functionality.

Main changes:

1. New configuration options:
   1. `trace-prompt`: Enables recording prompts to trace
   2. `trace-completion` : Enables recording completions to trace
   3. `trace-prompt-size` : Limits the length of prompt context
   4. `content-formatter` : Handles content formatting, currently supporting both 'text' and 'langfuse' modes
2. Added two handlers, ChatModelCompletionObservationTraceHandler and ChatModelPromptContentObservationTraceHandler, to support recording context to trace.
3. Introduced the MessageFormatter interface and its subclasses to support formatting for prompt and completion content.
4. Rolled back parts of the code and dependencies from commit ca843e8.

Signed-off-by: tingchuan.li <[email protected]>

Author: traburiss

auto-configurations/models/chat/observation/spring-ai-autoconfigure-model-chat-observation/src/main/java/org/springframework/ai/model/chat/observation/autoconfigure/ChatObservationAutoConfiguration.java

@@ -26,10 +26,7 @@
 import org.springframework.ai.chat.client.advisor.observation.AdvisorObservationContext;
 import org.springframework.ai.chat.client.observation.ChatClientObservationContext;
 import org.springframework.ai.chat.model.ChatModel;
-import org.springframework.ai.chat.observation.ChatModelCompletionObservationHandler;
-import org.springframework.ai.chat.observation.ChatModelMeterObservationHandler;
-import org.springframework.ai.chat.observation.ChatModelObservationContext;
-import org.springframework.ai.chat.observation.ChatModelPromptContentObservationHandler;
+import org.springframework.ai.chat.observation.*;
 import org.springframework.ai.embedding.observation.EmbeddingModelObservationContext;
 import org.springframework.ai.image.observation.ImageModelObservationContext;
 import org.springframework.ai.model.observation.ErrorLoggingObservationHandler;
@@ -70,6 +67,16 @@ private static void logCompletionWarning() {
 				"You have enabled logging out the completion content with the risk of exposing sensitive or private information. Please, be careful!");
 	}
 
+	private static void tracePromptContentWarning() {
+		logger.warn(
+				"You have enabled tracing out the prompt content with the risk of exposing sensitive or private information. Please, be careful!");
+	}
+
+	private static void traceCompletionWarning() {
+		logger.warn(
+				"You have enabled tracing out the completion content with the risk of exposing sensitive or private information. Please, be careful!");
+	}
+
 	@Bean
 	@ConditionalOnMissingBean
 	@ConditionalOnBean(MeterRegistry.class)
@@ -104,6 +111,30 @@ TracingAwareLoggingObservationHandler<ChatModelObservationContext> chatModelComp
 			return new TracingAwareLoggingObservationHandler<>(new ChatModelCompletionObservationHandler(), tracer);
 		}
 
+		@Bean
+		@ConditionalOnMissingBean(value = ChatModelPromptContentObservationTraceHandler.class,
+				name = "chatModelPromptContentObservationTraceHandler")
+		@ConditionalOnProperty(prefix = ChatObservationProperties.CONFIG_PREFIX, name = "trace-prompt",
+				havingValue = "true")
+		TracingAwareLoggingObservationHandler<ChatModelObservationContext> chatModelPromptContentObservationTraceHandler(
+				ChatObservationProperties properties, Tracer tracer) {
+			tracePromptContentWarning();
+			return new TracingAwareLoggingObservationHandler<>(new ChatModelPromptContentObservationTraceHandler(
+					properties.getContentFormatter(), properties.getTracePromptSize()), tracer);
+		}
+
+		@Bean
+		@ConditionalOnMissingBean(value = ChatModelCompletionObservationTraceHandler.class,
+				name = "chatModelCompletionObservationTraceHandler")
+		@ConditionalOnProperty(prefix = ChatObservationProperties.CONFIG_PREFIX, name = "trace-completion",
+				havingValue = "true")
+		TracingAwareLoggingObservationHandler<ChatModelObservationContext> chatModelCompletionObservationTraceHandler(
+				ChatObservationProperties properties, Tracer tracer) {
+			traceCompletionWarning();
+			return new TracingAwareLoggingObservationHandler<>(
+					new ChatModelCompletionObservationTraceHandler(properties.getContentFormatter()), tracer);
+		}
+
 		@Bean
 		@ConditionalOnMissingBean
 		@ConditionalOnProperty(prefix = ChatObservationProperties.CONFIG_PREFIX, name = "include-error-logging",
@@ -139,6 +170,27 @@ ChatModelCompletionObservationHandler chatModelCompletionObservationHandler() {
 			return new ChatModelCompletionObservationHandler();
 		}
 
+		@Bean
+		@ConditionalOnMissingBean()
+		@ConditionalOnProperty(prefix = ChatObservationProperties.CONFIG_PREFIX, name = "trace-prompt",
+				havingValue = "true")
+		ChatModelPromptContentObservationTraceHandler chatModelPromptContentObservationTraceHandler(
+				ChatObservationProperties properties) {
+			tracePromptContentWarning();
+			return new ChatModelPromptContentObservationTraceHandler(properties.getContentFormatter(),
+					properties.getTracePromptSize());
+		}
+
+		@Bean
+		@ConditionalOnMissingBean()
+		@ConditionalOnProperty(prefix = ChatObservationProperties.CONFIG_PREFIX, name = "trace-completion",
+				havingValue = "true")
+		ChatModelCompletionObservationTraceHandler chatModelCompletionObservationTraceHandler(
+				ChatObservationProperties properties) {
+			traceCompletionWarning();
+			return new ChatModelCompletionObservationTraceHandler(properties.getContentFormatter());
+		}
+
 	}
 
 }

auto-configurations/models/chat/observation/spring-ai-autoconfigure-model-chat-observation/src/main/java/org/springframework/ai/model/chat/observation/autoconfigure/ChatObservationProperties.java

@@ -16,6 +16,7 @@
 
 package org.springframework.ai.model.chat.observation.autoconfigure;
 
+import org.springframework.ai.chat.observation.trace.AiObservationContentFormatterName;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 
 /**
@@ -40,6 +41,26 @@ public class ChatObservationProperties {
 	 */
 	private boolean logPrompt = false;
 
+	/**
+	 * Whether to trace the completion content in the observations.
+	 */
+	private boolean traceCompletion = false;
+
+	/**
+	 * Whether to trace the prompt content in the observations.
+	 */
+	private boolean tracePrompt = false;
+
+	/**
+	 * prompt size in trace, smaller than 1 is unlimit
+	 */
+	private int tracePromptSize = 10;
+
+	/**
+	 * prompt and completion formatter
+	 */
+	private AiObservationContentFormatterName contentFormatter = AiObservationContentFormatterName.TEXT;
+
 	/**
 	 * Whether to include error logging in the observations.
 	 */
@@ -61,6 +82,38 @@ public void setLogPrompt(boolean logPrompt) {
 		this.logPrompt = logPrompt;
 	}
 
+	public boolean isTraceCompletion() {
+		return traceCompletion;
+	}
+
+	public void setTraceCompletion(boolean traceCompletion) {
+		this.traceCompletion = traceCompletion;
+	}
+
+	public boolean isTracePrompt() {
+		return tracePrompt;
+	}
+
+	public void setTracePrompt(boolean tracePrompt) {
+		this.tracePrompt = tracePrompt;
+	}
+
+	public int getTracePromptSize() {
+		return tracePromptSize;
+	}
+
+	public void setTracePromptSize(int tracePromptSize) {
+		this.tracePromptSize = tracePromptSize;
+	}
+
+	public AiObservationContentFormatterName getContentFormatter() {
+		return contentFormatter;
+	}
+
+	public void setContentFormatter(AiObservationContentFormatterName contentFormatter) {
+		this.contentFormatter = contentFormatter;
+	}
+
 	public boolean isIncludeErrorLogging() {
 		return this.includeErrorLogging;
 	}