feat: Support for Chat Flow & Agent Support for binding a single chat flow (#765)

Co-authored-by: Yu Yang <72337138+tomasyu985@users.noreply.github.com>
Co-authored-by: zengxiaohui <csu.zengxiaohui@gmail.com>
Co-authored-by: lijunwen.gigoo <lijunwen.gigoo@bytedance.com>
Co-authored-by: lvxinyu.1117 <lvxinyu.1117@bytedance.com>
Co-authored-by: liuyunchao.0510 <liuyunchao.0510@bytedance.com>
Co-authored-by: haozhenfei <37089575+haozhenfei@users.noreply.github.com>
Co-authored-by: July <jiangxujin@bytedance.com>
Co-authored-by: tecvan-fe <fanwenjie.fe@bytedance.com>

backend/domain/workflow/internal/nodes/intentdetector/intent_detector.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"maps"
 	"strconv"
 	"strings"
 
@@ -29,21 +30,26 @@ import (
 	"github.com/spf13/cast"
 
 	model "github.com/coze-dev/coze-studio/backend/api/model/crossdomain/modelmgr"
+	crossmessage "github.com/coze-dev/coze-studio/backend/crossdomain/contract/message"
 	crossmodelmgr "github.com/coze-dev/coze-studio/backend/crossdomain/contract/modelmgr"
 	"github.com/coze-dev/coze-studio/backend/domain/workflow/entity"
 	"github.com/coze-dev/coze-studio/backend/domain/workflow/entity/vo"
 	"github.com/coze-dev/coze-studio/backend/domain/workflow/internal/canvas/convert"
+	"github.com/coze-dev/coze-studio/backend/domain/workflow/internal/execute"
 	"github.com/coze-dev/coze-studio/backend/domain/workflow/internal/nodes"
 	schema2 "github.com/coze-dev/coze-studio/backend/domain/workflow/internal/schema"
+	"github.com/coze-dev/coze-studio/backend/pkg/ctxcache"
 	"github.com/coze-dev/coze-studio/backend/pkg/lang/ternary"
+	"github.com/coze-dev/coze-studio/backend/pkg/logs"
 	"github.com/coze-dev/coze-studio/backend/pkg/sonic"
 )
 
 type Config struct {
-	Intents      []string
-	SystemPrompt string
-	IsFastMode   bool
-	LLMParams    *model.LLMParams
+	Intents            []string
+	SystemPrompt       string
+	IsFastMode         bool
+	LLMParams          *model.LLMParams
+	ChatHistorySetting *vo.ChatHistorySetting
 }
 
 func (c *Config) Adapt(_ context.Context, n *vo.Node, _ ...nodes.AdaptOption) (*schema2.NodeSchema, error) {
@@ -59,6 +65,10 @@ func (c *Config) Adapt(_ context.Context, n *vo.Node, _ ...nodes.AdaptOption) (*
 		return nil, fmt.Errorf("intent detector node's llmParam is nil")
 	}
 
+	if n.Data.Inputs.ChatHistorySetting != nil {
+		c.ChatHistorySetting = n.Data.Inputs.ChatHistorySetting
+	}
+
 	llmParam, ok := param.(vo.IntentDetectorLLMParam)
 	if !ok {
 		return nil, fmt.Errorf("llm node's llmParam must be LLMParam, got %v", llmParam)
@@ -141,14 +151,16 @@ func (c *Config) Build(ctx context.Context, _ *schema2.NodeSchema, _ ...schema2.
 		&schema.Message{Content: sptTemplate, Role: schema.System},
 		&schema.Message{Content: "{{query}}", Role: schema.User})
 
-	r, err := chain.AppendChatTemplate(prompts).AppendChatModel(m).Compile(ctx)
+	r, err := chain.AppendChatTemplate(newHistoryChatTemplate(prompts, c.ChatHistorySetting)).AppendChatModel(m).Compile(ctx)
 	if err != nil {
 		return nil, err
 	}
+
 	return &IntentDetector{
-		isFastMode:   c.IsFastMode,
-		systemPrompt: c.SystemPrompt,
-		runner:       r,
+		isFastMode:         c.IsFastMode,
+		systemPrompt:       c.SystemPrompt,
+		runner:             r,
+		ChatHistorySetting: c.ChatHistorySetting,
 	}, nil
 }
 
@@ -182,6 +194,10 @@ func (c *Config) ExpectPorts(ctx context.Context, n *vo.Node) []string {
 	return expects
 }
 
+type contextKey string
+
+const chatHistoryKey contextKey = "chatHistory"
+
 const SystemIntentPrompt = `
 # Role
 You are an intention classification expert, good at being able to judge which classification the user's input belongs to.
@@ -240,9 +256,10 @@ Note:
 const classificationID = "classificationId"
 
 type IntentDetector struct {
-	isFastMode   bool
-	systemPrompt string
-	runner       compose.Runnable[map[string]any, *schema.Message]
+	isFastMode         bool
+	systemPrompt       string
+	runner             compose.Runnable[map[string]any, *schema.Message]
+	ChatHistorySetting *vo.ChatHistorySetting
 }
 
 func (id *IntentDetector) parseToNodeOut(content string) (map[string]any, error) {
@@ -320,3 +337,66 @@ func toIntentString(its []string) (string, error) {
 
 	return sonic.MarshalString(vs)
 }
+
+func (id *IntentDetector) ToCallbackInput(ctx context.Context, in map[string]any) (map[string]any, error) {
+	if id.ChatHistorySetting == nil || !id.ChatHistorySetting.EnableChatHistory {
+		return in, nil
+	}
+
+	var messages []*crossmessage.WfMessage
+	var scMessages []*schema.Message
+	var sectionID *int64
+	execCtx := execute.GetExeCtx(ctx)
+	if execCtx != nil {
+		messages = execCtx.ExeCfg.ConversationHistory
+		scMessages = execCtx.ExeCfg.ConversationHistorySchemaMessages
+		sectionID = execCtx.ExeCfg.SectionID
+	}
+
+	ret := map[string]any{
+		"chatHistory": []any{},
+	}
+	maps.Copy(ret, in)
+
+	if len(messages) == 0 {
+		return ret, nil
+	}
+	if sectionID != nil && messages[0].SectionID != *sectionID {
+		return ret, nil
+	}
+
+	maxRounds := int(id.ChatHistorySetting.ChatHistoryRound)
+	if execCtx != nil && execCtx.ExeCfg.MaxHistoryRounds != nil {
+		maxRounds = min(int(*execCtx.ExeCfg.MaxHistoryRounds), maxRounds)
+	}
+
+	count := 0
+	startIdx := 0
+	for i := len(messages) - 1; i >= 0; i-- {
+		if messages[i].Role == schema.User {
+			count++
+		}
+		if count >= maxRounds {
+			startIdx = i
+			break
+		}
+	}
+
+	var historyMessages []any
+	for _, msg := range messages[startIdx:] {
+		content, err := nodes.ConvertMessageToString(ctx, msg)
+		if err != nil {
+			logs.CtxWarnf(ctx, "failed to convert message to string: %v", err)
+			continue
+		}
+		historyMessages = append(historyMessages, map[string]any{
+			"role":    string(msg.Role),
+			"content": content,
+		})
+	}
+
+	ctxcache.Store(ctx, chatHistoryKey, scMessages[startIdx:])
+
+	ret["chatHistory"] = historyMessages
+	return ret, nil
+}

backend/domain/workflow/internal/nodes/intentdetector/prompt.go

@@ -0,0 +1,85 @@
+/*
+ * Copyright 2025 coze-dev 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 intentdetector
+
+import (
+	"context"
+	"fmt"
+	"github.com/cloudwego/eino/components/prompt"
+	"github.com/cloudwego/eino/schema"
+
+	"github.com/coze-dev/coze-studio/backend/api/model/workflow"
+	"github.com/coze-dev/coze-studio/backend/domain/workflow/entity/vo"
+	"github.com/coze-dev/coze-studio/backend/domain/workflow/internal/execute"
+	"github.com/coze-dev/coze-studio/backend/pkg/ctxcache"
+	"github.com/coze-dev/coze-studio/backend/pkg/logs"
+)
+
+type historyChatTemplate struct {
+	basePrompt         prompt.ChatTemplate
+	chatHistorySetting *vo.ChatHistorySetting
+}
+
+func newHistoryChatTemplate(basePrompt prompt.ChatTemplate, chatHistorySetting *vo.ChatHistorySetting) prompt.ChatTemplate {
+	return &historyChatTemplate{
+		basePrompt:         basePrompt,
+		chatHistorySetting: chatHistorySetting,
+	}
+}
+
+func (t *historyChatTemplate) Format(ctx context.Context, vs map[string]any, opts ...prompt.Option) ([]*schema.Message, error) {
+	baseMessages, err := t.basePrompt.Format(ctx, vs, opts...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to format base prompt: %w", err)
+	}
+	if len(baseMessages) == 0 {
+		return nil, fmt.Errorf("base prompt returned no messages")
+	}
+
+	if t.chatHistorySetting == nil || !t.chatHistorySetting.EnableChatHistory {
+		return baseMessages, nil
+	}
+
+	exeCtx := execute.GetExeCtx(ctx)
+	if exeCtx == nil {
+		logs.CtxWarnf(ctx, "execute context is nil, skipping chat history")
+		return baseMessages, nil
+	}
+
+	if exeCtx.ExeCfg.WorkflowMode != workflow.WorkflowMode_ChatFlow {
+		return baseMessages, nil
+	}
+
+	historyMessages, ok := ctxcache.Get[[]*schema.Message](ctx, chatHistoryKey)
+	if !ok || len(historyMessages) == 0 {
+		logs.CtxWarnf(ctx, "conversation history is empty")
+		return baseMessages, nil
+	}
+
+	if len(historyMessages) == 0 {
+		return baseMessages, nil
+	}
+
+	finalMessages := make([]*schema.Message, 0, len(baseMessages)+len(historyMessages))
+	finalMessages = append(finalMessages, baseMessages[0]) // System prompt
+	finalMessages = append(finalMessages, historyMessages...)
+	if len(baseMessages) > 1 {
+		finalMessages = append(finalMessages, baseMessages[1:]...) // User prompt and any others
+	}
+
+	return finalMessages, nil
+}