chore: update approval example to be easier to understand

Change-Id: Ia999549cce2940aee6d2e1e57ad90c28d5d2f15f

adk/common/tool/approval_wrapper.go

@@ -29,7 +29,6 @@ type ApprovalInfo struct {
 	ToolName        string
 	ArgumentsInJSON string
 	ToolCallID      string
-	ApprovalResult  *ApprovalResult
 }
 
 type ApprovalResult struct {
@@ -72,7 +71,7 @@ func (i InvokableApprovableTool) InvokableRun(ctx context.Context, argumentsInJS
 		}, argumentsInJSON)
 	}
 
-	isResumeTarget, hasData, data := compose.GetResumeContext[*ApprovalInfo](ctx)
+	isResumeTarget, hasData, data := compose.GetResumeContext[*ApprovalResult](ctx)
 	if !isResumeTarget { // was interrupted but not explicitly resumed, reinterrupt and wait for approval again
 		return "", compose.StatefulInterrupt(ctx, &ApprovalInfo{
 			ToolName:        toolInfo.Name,
@@ -84,16 +83,12 @@ func (i InvokableApprovableTool) InvokableRun(ctx context.Context, argumentsInJS
 		return "", fmt.Errorf("tool '%s' resumed with no data", toolInfo.Name)
 	}
 
-	if data.ApprovalResult == nil {
-		return "", fmt.Errorf("tool '%s' resumed with no approval result", toolInfo.Name)
-	}
-
-	if data.ApprovalResult.Approved {
+	if data.Approved {
 		return i.InvokableTool.InvokableRun(ctx, storedArguments, opts...)
 	}
 
-	if data.ApprovalResult.DisapproveReason != nil {
-		return fmt.Sprintf("tool '%s' disapproved, reason: %s", toolInfo.Name, *data.ApprovalResult.DisapproveReason), nil
+	if data.DisapproveReason != nil {
+		return fmt.Sprintf("tool '%s' disapproved, reason: %s", toolInfo.Name, *data.DisapproveReason), nil
 	}
 
 	return fmt.Sprintf("tool '%s' disapproved", toolInfo.Name), nil

adk/human-in-the-loop/1_approval/agent.go

@@ -22,14 +22,33 @@ import (
 	"log"
 
 	"github.com/cloudwego/eino/adk"
+	"github.com/cloudwego/eino/components/tool"
+	"github.com/cloudwego/eino/components/tool/utils"
 	"github.com/cloudwego/eino/compose"
 
 	"github.com/cloudwego/eino-examples/adk/common/model"
+	tool2 "github.com/cloudwego/eino-examples/adk/common/tool"
 )
 
 func NewTicketBookingAgent() adk.Agent {
 	ctx := context.Background()
 
+	type bookInput struct {
+		Location             string `json:"location"`
+		PassengerName        string `json:"passenger_name"`
+		PassengerPhoneNumber string `json:"passenger_phone_number"`
+	}
+
+	getWeather, err := utils.InferTool(
+		"BookTicket",
+		"this tool can book ticket of the specific location",
+		func(ctx context.Context, input bookInput) (output string, err error) {
+			return "success", nil
+		})
+	if err != nil {
+		log.Fatal(err)
+	}
+
 	a, err := adk.NewChatModelAgent(ctx, &adk.ChatModelAgentConfig{
 		Name:        "TicketBooker",
 		Description: "An agent that can book tickets",
@@ -38,7 +57,9 @@ Based on the user's request, use the "BookTicket" tool to book tickets.`,
 		Model: model.NewChatModel(),
 		ToolsConfig: adk.ToolsConfig{
 			ToolsNodeConfig: compose.ToolsNodeConfig{
-				Tools: getTools(),
+				Tools: []tool.BaseTool{
+					&tool2.InvokableApprovableTool{InvokableTool: getWeather},
+				},
 			},
 		},
 	})

adk/human-in-the-loop/1_approval/main.go

@@ -37,6 +37,10 @@ func main() {
 	runner := adk.NewRunner(ctx, adk.RunnerConfig{
 		EnableStreaming: true, // you can disable streaming here
 		Agent:           a,
+
+		// provide a CheckPointStore for eino to persist the execution state of the agent for later resumption.
+		// Here we use an in-memory store for simplicity.
+		// In the real world, you can use a distributed store like Redis to persist the checkpoints.
 		CheckPointStore: store.NewInMemoryStore(),
 	})
 	iter := runner.Query(ctx, "book a ticket for Martin, to Beijing, on 2025-12-01, the phone number is 1234567. directly call tool.", adk.WithCheckPointID("1"))
@@ -62,9 +66,12 @@ func main() {
 	if lastEvent.Action == nil || lastEvent.Action.Interrupted == nil {
 		log.Fatal("last event is not an interrupt event")
 	}
-	apInfo := lastEvent.Action.Interrupted.InterruptContexts[0].Info.(*tool.ApprovalInfo)
+
+	// this interruptID is crucial 'locator' for Eino to know where the interrupt happens,
+	// so when resuming later, you have to provide this same `interruptID` along with the approval result back to Eino
 	interruptID := lastEvent.Action.Interrupted.InterruptContexts[0].ID
 
+	var apResult *tool.ApprovalResult
 	for {
 		scanner := bufio.NewScanner(os.Stdin)
 		fmt.Print("your input here: ")
@@ -72,7 +79,7 @@ func main() {
 		fmt.Println()
 		nInput := scanner.Text()
 		if strings.ToUpper(nInput) == "Y" {
-			apInfo.ApprovalResult = &tool.ApprovalResult{Approved: true}
+			apResult = &tool.ApprovalResult{Approved: true}
 			break
 		} else if strings.ToUpper(nInput) == "N" {
 			// Prompt for reason when denying
@@ -80,16 +87,20 @@ func main() {
 			scanner.Scan()
 			reason := scanner.Text()
 			fmt.Println()
-			apInfo.ApprovalResult = &tool.ApprovalResult{Approved: false, DisapproveReason: &reason}
+			apResult = &tool.ApprovalResult{Approved: false, DisapproveReason: &reason}
 			break
 		}
 
 		fmt.Println("invalid input, please input Y or N")
 	}
 
+	// here we directly resumes right in the same instance where the original `Runner.Query` happened.
+	// In the real world, the original `Runner.Run/Query` and the subsequent `Runner.ResumeWithParams`
+	// can happen in different processes or machines, as long as you use the same `CheckPointID`,
+	// and you provided a distributed `CheckPointStore` when creating the `Runner` instance.
 	iter, err := runner.ResumeWithParams(ctx, "1", &adk.ResumeParams{
 		Targets: map[string]any{
-			interruptID: apInfo,
+			interruptID: apResult,
 		},
 	})
 	if err != nil {

adk/human-in-the-loop/1_approval/tool.go

@@ -1,49 +0,0 @@
-/*
- * 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 main
-
-import (
-	"context"
-	"log"
-
-	"github.com/cloudwego/eino/components/tool"
-	"github.com/cloudwego/eino/components/tool/utils"
-
-	tool2 "github.com/cloudwego/eino-examples/adk/common/tool"
-)
-
-type bookInput struct {
-	Location             string `json:"location"`
-	PassengerName        string `json:"passenger_name"`
-	PassengerPhoneNumber string `json:"passenger_phone_number"`
-}
-
-func getTools() []tool.BaseTool {
-	getWeather, err := utils.InferTool(
-		"BookTicket",
-		"this tool can book ticket of the specific location",
-		func(ctx context.Context, input bookInput) (output string, err error) {
-			return "success", nil
-		})
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	return []tool.BaseTool{
-		&tool2.InvokableApprovableTool{InvokableTool: getWeather},
-	}
-}