refactor: Add YAML snake_case to camelCase preprocessing and GenerateContentConfig support

This CL introduces a YAML preprocessor that converts snake_case keys to camelCase, aligning YAML configurations with Java naming conventions. It also integrates GenerateContentConfig into LlmAgent, allowing detailed control over content generation parameters. Jackson @JsonProperty annotations are removed as they are no longer necessary due to the preprocessing.

PiperOrigin-RevId: 803533936

Author: Doris26

core/pom.xml

@@ -81,6 +81,11 @@
       <artifactId>auto-value-annotations</artifactId>
       <scope>provided</scope>
     </dependency>
+    <dependency>
+      <groupId>com.google.guava</groupId>
+      <artifactId>guava</artifactId>
+      <version>33.0.0-jre</version>
+    </dependency>
     <dependency>
       <groupId>com.google.errorprone</groupId>
       <artifactId>error_prone_annotations</artifactId>

core/src/main/java/com/google/adk/agents/BaseAgentConfig.java

@@ -16,7 +16,6 @@
 
 package com.google.adk.agents;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
 import java.util.List;
 
 /**
@@ -66,7 +65,6 @@ public AgentRefConfig(String name, String className, String staticField) {
       this.staticField = staticField;
     }
 
-    @JsonProperty("name")
     public String name() {
       return name;
     }
@@ -75,7 +73,6 @@ public void setName(String name) {
       this.name = name;
     }
 
-    @JsonProperty("config_path")
     public String configPath() {
       return configPath;
     }
@@ -84,7 +81,6 @@ public void setConfigPath(String configPath) {
       this.configPath = configPath;
     }
 
-    @JsonProperty("class_name")
     public String className() {
       return className;
     }
@@ -93,7 +89,6 @@ public void setClassName(String className) {
       this.className = className;
     }
 
-    @JsonProperty("static_field")
     public String staticField() {
       return staticField;
     }
@@ -133,7 +128,6 @@ public BaseAgentConfig(String name, String description, String agentClass) {
     this.agentClass = agentClass;
   }
 
-  @JsonProperty(value = "name", required = true)
   public String name() {
     return name;
   }
@@ -142,7 +136,6 @@ public void setName(String name) {
     this.name = name;
   }
 
-  @JsonProperty("description")
   public String description() {
     return description;
   }
@@ -151,7 +144,6 @@ public void setDescription(String description) {
     this.description = description;
   }
 
-  @JsonProperty("agent_class")
   public String agentClass() {
     return agentClass;
   }
@@ -160,7 +152,6 @@ public void setAgentClass(String agentClass) {
     this.agentClass = agentClass;
   }
 
-  @JsonProperty("sub_agents")
   public List<AgentRefConfig> subAgents() {
     return subAgents;
   }

core/src/main/java/com/google/adk/agents/ConfigAgentUtils.java

@@ -17,14 +17,15 @@
 package com.google.adk.agents;
 
 import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.MapperFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
 import com.google.adk.utils.ComponentRegistry;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
-import java.io.FileInputStream;
 import java.io.IOException;
-import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -187,11 +188,18 @@ private static BaseAgent resolveSubAgentFromConfigPath(
    */
   private static <T extends BaseAgentConfig> T loadConfigAsType(
       String configPath, Class<T> configClass) throws ConfigurationException {
-    try (InputStream inputStream = new FileInputStream(configPath)) {
-      ObjectMapper mapper = new ObjectMapper(new YAMLFactory());
-      mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
-      mapper.enable(com.fasterxml.jackson.databind.MapperFeature.ACCEPT_CASE_INSENSITIVE_ENUMS);
-      return mapper.readValue(inputStream, configClass);
+    try {
+      String yamlContent = Files.readString(Paths.get(configPath), StandardCharsets.UTF_8);
+
+      // Preprocess YAML to convert snake_case to camelCase
+      String processedYaml = YamlPreprocessor.preprocessYaml(yamlContent);
+
+      ObjectMapper mapper =
+          JsonMapper.builder(new YAMLFactory())
+              .disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
+              .enable(MapperFeature.ACCEPT_CASE_INSENSITIVE_ENUMS)
+              .build();
+      return mapper.readValue(processedYaml, configClass);
     } catch (IOException e) {
       throw new ConfigurationException("Failed to load or parse config file: " + configPath, e);
     }

core/src/main/java/com/google/adk/agents/LlmAgent.java

@@ -965,6 +965,11 @@ public static LlmAgent fromConfig(LlmAgentConfig config, String configAbsPath)
       builder.includeContents(config.includeContents());
     }
 
+    // Set optional generateContentConfig
+    if (config.generateContentConfig() != null) {
+      builder.generateContentConfig(config.generateContentConfig());
+    }
+
     // Build and return the agent
     LlmAgent agent = builder.build();
     logger.info(

core/src/main/java/com/google/adk/agents/LlmAgentConfig.java

@@ -16,9 +16,9 @@
 
 package com.google.adk.agents;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
 import com.google.adk.agents.LlmAgent.IncludeContents;
 import com.google.adk.tools.BaseTool.ToolConfig;
+import com.google.genai.types.GenerateContentConfig;
 import java.util.List;
 
 /**
@@ -34,14 +34,14 @@ public class LlmAgentConfig extends BaseAgentConfig {
   private String outputKey;
   private List<ToolConfig> tools;
   private IncludeContents includeContents;
+  private GenerateContentConfig generateContentConfig;
 
   public LlmAgentConfig() {
     super();
     setAgentClass("LlmAgent");
   }
 
-  // Non-standard accessors with JsonProperty annotations
-  @JsonProperty("model")
+  // Accessors
   public String model() {
     return model;
   }
@@ -50,7 +50,6 @@ public void setModel(String model) {
     this.model = model;
   }
 
-  @JsonProperty(value = "instruction", required = true)
   public String instruction() {
     return instruction;
   }
@@ -59,7 +58,6 @@ public void setInstruction(String instruction) {
     this.instruction = instruction;
   }
 
-  @JsonProperty("disallow_transfer_to_parent")
   public Boolean disallowTransferToParent() {
     return disallowTransferToParent;
   }
@@ -68,7 +66,6 @@ public void setDisallowTransferToParent(Boolean disallowTransferToParent) {
     this.disallowTransferToParent = disallowTransferToParent;
   }
 
-  @JsonProperty("disallow_transfer_to_peers")
   public Boolean disallowTransferToPeers() {
     return disallowTransferToPeers;
   }
@@ -77,7 +74,6 @@ public void setDisallowTransferToPeers(Boolean disallowTransferToPeers) {
     this.disallowTransferToPeers = disallowTransferToPeers;
   }
 
-  @JsonProperty("output_key")
   public String outputKey() {
     return outputKey;
   }
@@ -86,7 +82,6 @@ public void setOutputKey(String outputKey) {
     this.outputKey = outputKey;
   }
 
-  @JsonProperty("tools")
   public List<ToolConfig> tools() {
     return tools;
   }
@@ -95,12 +90,19 @@ public void setTools(List<ToolConfig> tools) {
     this.tools = tools;
   }
 
-  @JsonProperty("include_contents")
   public IncludeContents includeContents() {
     return includeContents;
   }
 
   public void setIncludeContents(IncludeContents includeContents) {
     this.includeContents = includeContents;
   }
+
+  public GenerateContentConfig generateContentConfig() {
+    return generateContentConfig;
+  }
+
+  public void setGenerateContentConfig(GenerateContentConfig generateContentConfig) {
+    this.generateContentConfig = generateContentConfig;
+  }
 }