Simplify and remove duplicate logic in AI model observation components.

Closes #1653

Author: jxblum

spring-ai-core/src/main/java/org/springframework/ai/chat/observation/ChatModelCompletionObservationFilter.java

@@ -22,26 +22,28 @@
 import org.springframework.ai.observation.tracing.TracingHelper;
 
 /**
- * An {@link ObservationFilter} to include the chat completion content in the observation.
+ * {@link ObservationFilter} used to include chat completion content in the
+ * {@link Observation}.
  *
  * @author Thomas Vitale
+ * @author John Blum
  * @since 1.0.0
  */
 public class ChatModelCompletionObservationFilter implements ObservationFilter {
 
 	@Override
 	public Observation.Context map(Observation.Context context) {
-		if (!(context instanceof ChatModelObservationContext chatModelObservationContext)) {
-			return context;
-		}
 
-		var completions = ChatModelObservationContentProcessor.completion(chatModelObservationContext);
+		if (context instanceof ChatModelObservationContext chatModelObservationContext) {
+
+			var completions = ChatModelObservationContentProcessor.completion(chatModelObservationContext);
 
-		chatModelObservationContext
-			.addHighCardinalityKeyValue(ChatModelObservationDocumentation.HighCardinalityKeyNames.COMPLETION
-				.withValue(TracingHelper.concatenateStrings(completions)));
+			context = chatModelObservationContext
+				.addHighCardinalityKeyValue(ChatModelObservationDocumentation.HighCardinalityKeyNames.COMPLETION
+					.withValue(TracingHelper.concatenateStrings(completions)));
+		}
 
-		return chatModelObservationContext;
+		return context;
 	}
 
 }

spring-ai-core/src/main/java/org/springframework/ai/chat/observation/ChatModelMeterObservationHandler.java

@@ -16,16 +16,25 @@
 
 package org.springframework.ai.chat.observation;
 
+import java.util.Optional;
+
 import io.micrometer.core.instrument.MeterRegistry;
 import io.micrometer.observation.Observation;
 import io.micrometer.observation.ObservationHandler;
 
+import org.springframework.ai.chat.metadata.ChatResponseMetadata;
+import org.springframework.ai.chat.metadata.Usage;
+import org.springframework.ai.chat.model.ChatResponse;
 import org.springframework.ai.model.observation.ModelUsageMetricsGenerator;
+import org.springframework.lang.Nullable;
 
 /**
- * Handler for generating metrics from chat model observations.
+ * {@link ObservationHandler} used to generate metrics from chat model observations.
  *
  * @author Thomas Vitale
+ * @author John Blum
+ * @see ChatModelObservationContext
+ * @see ObservationHandler
  * @since 1.0.0
  */
 public class ChatModelMeterObservationHandler implements ObservationHandler<ChatModelObservationContext> {
@@ -38,11 +47,16 @@ public ChatModelMeterObservationHandler(MeterRegistry meterRegistry) {
 
 	@Override
 	public void onStop(ChatModelObservationContext context) {
-		if (context.getResponse() != null && context.getResponse().getMetadata() != null
-				&& context.getResponse().getMetadata().getUsage() != null) {
-			ModelUsageMetricsGenerator.generate(context.getResponse().getMetadata().getUsage(), context,
-					this.meterRegistry);
-		}
+		resolveUsage(context)
+			.ifPresent(usage -> ModelUsageMetricsGenerator.generate(usage, context, this.meterRegistry));
+	}
+
+	private Optional<Usage> resolveUsage(@Nullable ChatModelObservationContext context) {
+
+		return Optional.ofNullable(context)
+			.map(ChatModelObservationContext::getResponse)
+			.map(ChatResponse::getMetadata)
+			.map(ChatResponseMetadata::getUsage);
 	}
 
 	@Override

spring-ai-core/src/main/java/org/springframework/ai/chat/observation/ChatModelObservationContentProcessor.java

@@ -16,46 +16,45 @@
 
 package org.springframework.ai.chat.observation;
 
+import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
 
+import org.springframework.ai.chat.messages.Message;
+import org.springframework.ai.chat.model.ChatResponse;
+import org.springframework.ai.chat.model.Generation;
 import org.springframework.ai.model.Content;
+import org.springframework.lang.Nullable;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.StringUtils;
 
 /**
  * Utilities to process the prompt and completion content in observations for chat models.
  *
  * @author Thomas Vitale
+ * @author John Blum
+ * @since 1.0.0
  */
-public final class ChatModelObservationContentProcessor {
-
-	private ChatModelObservationContentProcessor() {
-	}
+public abstract class ChatModelObservationContentProcessor {
 
 	public static List<String> prompt(ChatModelObservationContext context) {
-		if (CollectionUtils.isEmpty(context.getRequest().getInstructions())) {
-			return List.of();
-		}
 
-		return context.getRequest().getInstructions().stream().map(Content::getContent).toList();
-	}
+		List<Message> instructions = context.getRequest().getInstructions();
 
-	public static List<String> completion(ChatModelObservationContext context) {
-		if (context == null || context.getResponse() == null || context.getResponse().getResults() == null
-				|| CollectionUtils.isEmpty(context.getResponse().getResults())) {
-			return List.of();
-		}
+		return CollectionUtils.isEmpty(instructions) ? Collections.emptyList()
+				: instructions.stream().map(Content::getContent).toList();
+	}
 
-		if (!StringUtils.hasText(context.getResponse().getResult().getOutput().getContent())) {
-			return List.of();
-		}
+	public static List<String> completion(@Nullable ChatModelObservationContext context) {
 
-		return context.getResponse()
-			.getResults()
+		return Optional.ofNullable(context)
+			.map(ChatModelObservationContext::getResponse)
+			.map(ChatResponse::getResults)
+			.orElseGet(Collections::emptyList)
 			.stream()
-			.filter(generation -> generation.getOutput() != null
-					&& StringUtils.hasText(generation.getOutput().getContent()))
-			.map(generation -> generation.getOutput().getContent())
+			.map(Generation::getOutput)
+			.map(Message::getContent)
+			.filter(StringUtils::hasText)
 			.toList();
 	}
 

spring-ai-core/src/main/java/org/springframework/ai/chat/observation/ChatModelPromptContentObservationFilter.java

@@ -25,23 +25,24 @@
  * An {@link ObservationFilter} to include the chat prompt content in the observation.
  *
  * @author Thomas Vitale
+ * @author John Blum
  * @since 1.0.0
  */
 public class ChatModelPromptContentObservationFilter implements ObservationFilter {
 
 	@Override
 	public Observation.Context map(Observation.Context context) {
-		if (!(context instanceof ChatModelObservationContext chatModelObservationContext)) {
-			return context;
-		}
 
-		var prompts = ChatModelObservationContentProcessor.prompt(chatModelObservationContext);
+		if (context instanceof ChatModelObservationContext chatModelObservationContext) {
+
+			var prompts = ChatModelObservationContentProcessor.prompt(chatModelObservationContext);
 
-		chatModelObservationContext
-			.addHighCardinalityKeyValue(ChatModelObservationDocumentation.HighCardinalityKeyNames.PROMPT
-				.withValue(TracingHelper.concatenateStrings(prompts)));
+			context = chatModelObservationContext
+				.addHighCardinalityKeyValue(ChatModelObservationDocumentation.HighCardinalityKeyNames.PROMPT
+					.withValue(TracingHelper.concatenateStrings(prompts)));
+		}
 
-		return chatModelObservationContext;
+		return context;
 	}
 
 }