04记忆、Session 与流式输出

/*
 * Copyright 2025 CloudWeGo Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package adk

import (
  "bytes"
  "context"
  "encoding/gob"
  "errors"
  "fmt"
  "io"
  "sort"
  "sync"
  "time"

  "github.com/cloudwego/eino/schema"
)

// runSession CheckpointSchema: persisted via serialization.RunCtx (gob).
type runSession struct {
  Values    map[string]any
  valuesMtx *sync.Mutex

  Events     []*agentEventWrapper
  LaneEvents *laneEvents
  mtx        sync.Mutex
// … 这只是文件开头 40 行，并非完整声明；点击上方「浏览完整文件」

// GetSessionValues returns all session key-value pairs for the current run.
func GetSessionValues(ctx context.Context) map[string]any {
  session := getSession(ctx)
  if session == nil {
    return map[string]any{}
  }

  return session.getValues()
}

// TypedChatModelAgentConfig is the generic configuration for ChatModelAgent.
type TypedChatModelAgentConfig[M MessageType] struct {
  // Name of the agent. Better be unique across all agents.
  // Optional. If empty, the agent can still run standalone but cannot be used as
  // a sub-agent tool via NewAgentTool (which requires a non-empty Name).
  Name string
  // Description of the agent's capabilities.
  // Helps other agents determine whether to transfer tasks to this agent.
  // Optional. If empty, the agent can still run standalone but cannot be used as
  // a sub-agent tool via NewAgentTool (which requires a non-empty Description).
  Description string
  // Instruction used as the system prompt for this agent.
  // Optional. If empty, no system prompt will be used.
  // Supports f-string placeholders for session values in default GenModelInput, for example:
  // "You are a helpful assistant. The current time is {Time}. The current user is {User}."
  // These placeholders will be replaced with session values for "Time" and "User".
  Instruction string

  // Model is the chat model used by the agent.
  // If your ChatModelAgent uses any tools, this model must support the model.WithTools
  // call option, as that's how ChatModelAgent configures the model with tool information.
  Model model.BaseModel[M]

  ToolsConfig ToolsConfig

  // GenModelInput transforms instructions and input messages into the model's input format.
  // Optional. Defaults to defaultGenModelInput which combines instruction and messages.
  GenModelInput TypedGenModelInput[M]

  // Exit defines the tool used to terminate the agent process.
  // Optional. If nil, no Exit Action will be generated.
  // You can use the provided 'ExitTool' implementation directly.
  //
  // NOT RECOMMENDED: Agent transfer with full context sharing between agents has not proven
  // to be more effective empirically. Consider using ChatModelAgent with AgentTool
  // or DeepAgent instead for most multi-agent scenarios.
  Exit tool.BaseTool

  // OutputKey stores the agent's response in the session.
  // Optional. When set, stores output via AddSessionValue(ctx, outputKey, msg.Content).
  //
  // NOT RECOMMENDED: Agent transfer with full context sharing between agents has not proven
  // to be more effective empirically. Consider using ChatModelAgent with AgentTool
  // or DeepAgent instead for most multi-agent scenarios.
  OutputKey string

  // MaxIterations defines the upper limit of ChatModel generation cycles.
  // The agent will terminate with an error if this limit is exceeded.
// … 省略 109 行；完整声明 L259–415，点击上方「浏览完整文件」

// NewAsyncIteratorPair returns a paired async iterator and generator
// that share the same underlying channel.
func NewAsyncIteratorPair[T any]() (*AsyncIterator[T], *AsyncGenerator[T]) {
  ch := internal.NewUnboundedChan[T]()
  return &AsyncIterator[T]{ch}, &AsyncGenerator[T]{ch}
}