diff --git a/agent/canvas.py b/agent/canvas.py
index 80b28d3fb..0889b043a 100644
--- a/agent/canvas.py
+++ b/agent/canvas.py
@@ -156,8 +156,12 @@ class Canvas(ABC):
             self.components[k]["obj"].reset()
         self._embed_id = ""
 
+    def get_compnent_name(self, cid):
+        for n in self.dsl["graph"]["nodes"]:
+            if cid == n["id"]: return n["data"]["name"]
+        return ""
+
     def run(self, **kwargs):
-        ans = ""
         if self.answer:
             cpn_id = self.answer[0]
             self.answer.pop(0)
@@ -167,10 +171,10 @@ class Canvas(ABC):
                 ans = ComponentBase.be_output(str(e))
             self.path[-1].append(cpn_id)
             if kwargs.get("stream"):
-                assert isinstance(ans, partial)
-                return ans
-            self.history.append(("assistant", ans.to_dict("records")))
-            return ans
+                for an in ans():
+                    yield an
+            else: yield ans
+            return
 
         if not self.path:
             self.components["begin"]["obj"].run(self.history, **kwargs)
@@ -178,6 +182,8 @@ class Canvas(ABC):
 
         self.path.append([])
         ran = -1
+        waiting = []
+        without_dependent_checking = []
 
         def prepare2run(cpns):
             nonlocal ran, ans
@@ -188,14 +194,19 @@ class Canvas(ABC):
                     self.answer.append(c)
                 else:
                     logging.debug(f"Canvas.prepare2run: {c}")
-                    cpids = cpn.get_dependent_components()
-                    if any([c not in self.path[-1] for c in cpids]):
-                        continue
+                    if c not in without_dependent_checking:
+                        cpids = cpn.get_dependent_components()
+                        if any([cc not in self.path[-1] for cc in cpids]):
+                            if c not in waiting: waiting.append(c)
+                            continue
+                    yield "'{}' is running...".format(self.get_compnent_name(c))
                     ans = cpn.run(self.history, **kwargs)
                     self.path[-1].append(c)
             ran += 1
 
-        prepare2run(self.components[self.path[-2][-1]]["downstream"])
+        for m in prepare2run(self.components[self.path[-2][-1]]["downstream"]):
+            yield {"content": m, "running_status": True}
+
         while 0 <= ran < len(self.path[-1]):
             logging.debug(f"Canvas.run: {ran} {self.path}")
             cpn_id = self.path[-1][ran]
@@ -210,28 +221,39 @@ class Canvas(ABC):
                 assert switch_out in self.components, \
                     "{}'s output: {} not valid.".format(cpn_id, switch_out)
                 try:
-                    prepare2run([switch_out])
+                    for m in prepare2run([switch_out]):
+                        yield {"content": m, "running_status": True}
                 except Exception as e:
                     for p in [c for p in self.path for c in p][::-1]:
                         if p.lower().find("answer") >= 0:
                             self.get_component(p)["obj"].set_exception(e)
-                            prepare2run([p])
+                            for m in prepare2run([p]):
+                                yield {"content": m, "running_status": True}
                             break
                     logging.exception("Canvas.run got exception")
                     break
                 continue
 
             try:
-                prepare2run(cpn["downstream"])
+                for m in prepare2run(cpn["downstream"]):
+                    yield {"content": m, "running_status": True}
             except Exception as e:
                 for p in [c for p in self.path for c in p][::-1]:
                     if p.lower().find("answer") >= 0:
                         self.get_component(p)["obj"].set_exception(e)
-                        prepare2run([p])
+                        for m in prepare2run([p]):
+                            yield {"content": m, "running_status": True}
                         break
                 logging.exception("Canvas.run got exception")
                 break
 
+            if ran >= len(self.path[-1]) and waiting:
+                without_dependent_checking = waiting
+                waiting = []
+                for m in prepare2run(without_dependent_checking):
+                    yield {"content": m, "running_status": True}
+                ran -= 1
+
         if self.answer:
             cpn_id = self.answer[0]
             self.answer.pop(0)
@@ -239,11 +261,13 @@ class Canvas(ABC):
             self.path[-1].append(cpn_id)
             if kwargs.get("stream"):
                 assert isinstance(ans, partial)
-                return ans
+                for an in ans():
+                    yield an
+            else:
+                yield ans
 
-            self.history.append(("assistant", ans.to_dict("records")))
-
-        return ans
+        else:
+            raise Exception("The dialog flow has no way to interact with you. Please add an 'Interact' component to the end of the flow.")
 
     def get_component(self, cpn_id):
         return self.components[cpn_id]
diff --git a/agent/component/base.py b/agent/component/base.py
index 5a53c2736..fc44b4da7 100644
--- a/agent/component/base.py
+++ b/agent/component/base.py
@@ -13,17 +13,17 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 #
-import logging
 from abc import ABC
 import builtins
 import json
 import os
 from functools import partial
+from typing import Tuple, Union
 
 import pandas as pd
 
 from agent import settings
-
+from agent.settings import flow_logger, DEBUG
 
 _FEEDED_DEPRECATED_PARAMS = "_feeded_deprecated_params"
 _DEPRECATED_PARAMS = "_deprecated_params"
@@ -82,7 +82,6 @@ class ComponentParamBase(ABC):
         return {name: True for name in self.get_feeded_deprecated_params()}
 
     def __str__(self):
-
         return json.dumps(self.as_dict(), ensure_ascii=False)
 
     def as_dict(self):
@@ -398,8 +397,11 @@ class ComponentBase(ABC):
         self._param.check()
 
     def get_dependent_components(self):
-        cpnts = [para["component_id"] for para in self._param.query if para.get("component_id") and para["component_id"].lower().find("answer") < 0]
-        return cpnts
+        cpnts = set([para["component_id"].split("@")[0] for para in self._param.query \
+                     if para.get("component_id") \
+                     and para["component_id"].lower().find("answer") < 0 \
+                     and para["component_id"].lower().find("begin") < 0])
+        return list(cpnts)
 
     def run(self, history, **kwargs):
         logging.debug("{}, history: {}, kwargs: {}".format(self, json.dumps(history, ensure_ascii=False),
@@ -416,7 +418,7 @@ class ComponentBase(ABC):
     def _run(self, history, **kwargs):
         raise NotImplementedError()
 
-    def output(self, allow_partial=True) -> tuple[str, pd.DataFrame | partial]:
+    def output(self, allow_partial=True) -> Tuple[str, Union[pd.DataFrame, partial]]:
         o = getattr(self._param, self._param.output_var_name)
         if not isinstance(o, partial) and not isinstance(o, pd.DataFrame):
             if not isinstance(o, list): o = [o]
@@ -436,12 +438,19 @@ class ComponentBase(ABC):
 
     def reset(self):
         setattr(self._param, self._param.output_var_name, None)
+        self._param.inputs = []
 
     def set_output(self, v: pd.DataFrame):
         setattr(self._param, self._param.output_var_name, v)
 
     def get_input(self):
+        reversed_cpnts = []
+        if len(self._canvas.path) > 1:
+            reversed_cpnts.extend(self._canvas.path[-2])
+        reversed_cpnts.extend(self._canvas.path[-1])
+
         if self._param.query:
+            self._param.inputs = []
             outs = []
             for q in self._param.query:
                 if q["component_id"]:
@@ -449,9 +458,9 @@ class ComponentBase(ABC):
                         cpn_id, key = q["component_id"].split("@")
                         for p in self._canvas.get_component(cpn_id)["obj"]._param.query:
                             if p["key"] == key:
-                                outs.append(pd.DataFrame([{"content": p["value"]}]))
+                                outs.append(pd.DataFrame([{"content": p.get("value", "")}]))
                                 self._param.inputs.append({"component_id": q["component_id"],
-                                                           "content": p["value"]})
+                                                           "content": p.get("value", "")})
                                 break
                         else:
                             assert False, f"Can't find parameter '{key}' for {cpn_id}"
@@ -470,12 +479,8 @@ class ComponentBase(ABC):
                 return df
 
         upstream_outs = []
-        reversed_cpnts = []
-        if len(self._canvas.path) > 1:
-            reversed_cpnts.extend(self._canvas.path[-2])
-        reversed_cpnts.extend(self._canvas.path[-1])
 
-        logging.debug(f"{self.component_name} {reversed_cpnts[::-1]}")
+        if DEBUG: print(self.component_name, reversed_cpnts[::-1])
         for u in reversed_cpnts[::-1]:
             if self.get_component_name(u) in ["switch", "concentrator"]: continue
             if self.component_name.lower() == "generate" and self.get_component_name(u) == "retrieval":
@@ -484,7 +489,7 @@ class ComponentBase(ABC):
                     o["component_id"] = u
                     upstream_outs.append(o)
                     continue
-            if self.component_name.lower()!="answer" and u not in self._canvas.get_component(self._id)["upstream"]: continue
+            #if self.component_name.lower()!="answer" and u not in self._canvas.get_component(self._id)["upstream"]: continue
             if self.component_name.lower().find("switch") < 0 \
                     and self.get_component_name(u) in ["relevant", "categorize"]:
                 continue
@@ -502,14 +507,14 @@ class ComponentBase(ABC):
                 upstream_outs.append(o)
             break
 
-        assert upstream_outs, "Can't inference the where the component input is."
+        assert upstream_outs, "Can't inference the where the component input is. Please identify whose output is this component's input."
 
         df = pd.concat(upstream_outs, ignore_index=True)
         if "content" in df:
             df = df.drop_duplicates(subset=['content']).reset_index(drop=True)
 
         self._param.inputs = []
-        for _,r in df.iterrows():
+        for _, r in df.iterrows():
             self._param.inputs.append({"component_id": r["component_id"], "content": r["content"]})
 
         return df
diff --git a/agent/component/generate.py b/agent/component/generate.py
index b84d2fef0..856ee4309 100644
--- a/agent/component/generate.py
+++ b/agent/component/generate.py
@@ -63,9 +63,11 @@ class Generate(ComponentBase):
     component_name = "Generate"
 
     def get_dependent_components(self):
-        cpnts = [para["component_id"] for para in self._param.parameters if
-                 para.get("component_id") and para["component_id"].lower().find("answer") < 0]
-        return cpnts
+        cpnts = set([para["component_id"].split("@")[0] for para in self._param.parameters \
+                     if para.get("component_id") \
+                     and para["component_id"].lower().find("answer") < 0 \
+                     and para["component_id"].lower().find("begin") < 0])
+        return list(cpnts)
 
     def set_cite(self, retrieval_res, answer):
         retrieval_res = retrieval_res.dropna(subset=["vector", "content_ltks"]).reset_index(drop=True)
@@ -107,11 +109,12 @@ class Generate(ComponentBase):
         self._param.inputs = []
         for para in self._param.parameters:
             if not para.get("component_id"): continue
-            if para["component_id"].split("@")[0].lower().find("begin") > 0:
+            component_id = para["component_id"].split("@")[0]
+            if para["component_id"].lower().find("@") >= 0:
                 cpn_id, key = para["component_id"].split("@")
                 for p in self._canvas.get_component(cpn_id)["obj"]._param.query:
                     if p["key"] == key:
-                        kwargs[para["key"]] = p["value"]
+                        kwargs[para["key"]] = p.get("value", "")
                         self._param.inputs.append(
                             {"component_id": para["component_id"], "content": kwargs[para["key"]]})
                         break
@@ -119,7 +122,7 @@ class Generate(ComponentBase):
                     assert False, f"Can't find parameter '{key}' for {cpn_id}"
                 continue
 
-            cpn = self._canvas.get_component(para["component_id"])["obj"]
+            cpn = self._canvas.get_component(component_id)["obj"]
             if cpn.component_name.lower() == "answer":
                 kwargs[para["key"]] = self._canvas.get_history(1)[0]["content"]
                 continue
@@ -129,14 +132,12 @@ class Generate(ComponentBase):
             else:
                 if cpn.component_name.lower() == "retrieval":
                     retrieval_res.append(out)
-                kwargs[para["key"]] = "  - " + "\n - ".join(
-                    [o if isinstance(o, str) else str(o) for o in out["content"]])
+                kwargs[para["key"]] = "  - "+"\n - ".join([o if isinstance(o, str) else str(o) for o in out["content"]])
             self._param.inputs.append({"component_id": para["component_id"], "content": kwargs[para["key"]]})
 
         if retrieval_res:
             retrieval_res = pd.concat(retrieval_res, ignore_index=True)
-        else:
-            retrieval_res = pd.DataFrame([])
+        else: retrieval_res = pd.DataFrame([])
 
         for n, v in kwargs.items():
             prompt = re.sub(r"\{%s\}" % re.escape(n), re.escape(str(v)), prompt)
@@ -158,6 +159,7 @@ class Generate(ComponentBase):
             return pd.DataFrame([res])
 
         msg = self._canvas.get_history(self._param.message_history_window_size)
+        if len(msg) < 1: msg.append({"role": "user", "content": ""})
         _, msg = message_fit_in([{"role": "system", "content": prompt}, *msg], int(chat_mdl.max_length * 0.97))
         if len(msg) < 2: msg.append({"role": "user", "content": ""})
         ans = chat_mdl.chat(msg[0]["content"], msg[1:], self._param.gen_conf())
@@ -178,6 +180,7 @@ class Generate(ComponentBase):
             return
 
         msg = self._canvas.get_history(self._param.message_history_window_size)
+        if len(msg) < 1: msg.append({"role": "user", "content": ""})
         _, msg = message_fit_in([{"role": "system", "content": prompt}, *msg], int(chat_mdl.max_length * 0.97))
         if len(msg) < 2: msg.append({"role": "user", "content": ""})
         answer = ""
diff --git a/agent/component/switch.py b/agent/component/switch.py
index 84613ee04..05daaf96f 100644
--- a/agent/component/switch.py
+++ b/agent/component/switch.py
@@ -47,13 +47,35 @@ class SwitchParam(ComponentParamBase):
 class Switch(ComponentBase, ABC):
     component_name = "Switch"
 
+    def get_dependent_components(self):
+        res = []
+        for cond in self._param.conditions:
+            for item in cond["items"]:
+                if not item["cpn_id"]: continue
+                if item["cpn_id"].find("begin") >= 0:
+                    continue
+                cid = item["cpn_id"].split("@")[0]
+                res.append(cid)
+
+        return list(set(res))
+
     def _run(self, history, **kwargs):
         for cond in self._param.conditions:
             res = []
             for item in cond["items"]:
-                out = self._canvas.get_component(item["cpn_id"])["obj"].output()[1]
-                cpn_input = "" if "content" not in out.columns else " ".join([str(s) for s in out["content"]])
-                res.append(self.process_operator(cpn_input, item["operator"], item["value"]))
+                if not item["cpn_id"]:continue
+                cid = item["cpn_id"].split("@")[0]
+                if item["cpn_id"].find("@") > 0:
+                    cpn_id, key = item["cpn_id"].split("@")
+                    for p in self._canvas.get_component(cid)["obj"]._param.query:
+                        if p["key"] == key:
+                            res.append(self.process_operator(p.get("value",""), item["operator"], item.get("value", "")))
+                            break
+                else:
+                    out = self._canvas.get_component(cid)["obj"].output()[1]
+                    cpn_input = "" if "content" not in out.columns else " ".join([str(s) for s in out["content"]])
+                    res.append(self.process_operator(cpn_input, item["operator"], item.get("value", "")))
+
                 if cond["logical_operator"] != "and" and any(res):
                     return Switch.be_output(cond["to"])
 
diff --git a/api/apps/canvas_app.py b/api/apps/canvas_app.py
index a9d588432..6fb60fd53 100644
--- a/api/apps/canvas_app.py
+++ b/api/apps/canvas_app.py
@@ -15,11 +15,12 @@
 #
 import logging
 import json
+import traceback
 from functools import partial
 from flask import request, Response
 from flask_login import login_required, current_user
 from api.db.services.canvas_service import CanvasTemplateService, UserCanvasService
-from api import settings
+from api.settings import RetCode
 from api.utils import get_uuid
 from api.utils.api_utils import get_json_result, server_error_response, validate_request, get_data_error_result
 from agent.canvas import Canvas
@@ -36,8 +37,7 @@ def templates():
 @login_required
 def canvas_list():
     return get_json_result(data=sorted([c.to_dict() for c in \
-                                        UserCanvasService.query(user_id=current_user.id)],
-                                       key=lambda x: x["update_time"] * -1)
+                                 UserCanvasService.query(user_id=current_user.id)], key=lambda x: x["update_time"]*-1)
                            )
 
 
@@ -46,10 +46,10 @@ def canvas_list():
 @login_required
 def rm():
     for i in request.json["canvas_ids"]:
-        if not UserCanvasService.query(user_id=current_user.id, id=i):
+        if not UserCanvasService.query(user_id=current_user.id,id=i):
             return get_json_result(
                 data=False, message='Only owner of canvas authorized for this operation.',
-                code=settings.RetCode.OPERATING_ERROR)
+                code=RetCode.OPERATING_ERROR)
         UserCanvasService.delete_by_id(i)
     return get_json_result(data=True)
 
@@ -73,7 +73,7 @@ def save():
         if not UserCanvasService.query(user_id=current_user.id, id=req["id"]):
             return get_json_result(
                 data=False, message='Only owner of canvas authorized for this operation.',
-                code=settings.RetCode.OPERATING_ERROR)
+                code=RetCode.OPERATING_ERROR)
         UserCanvasService.update_by_id(req["id"], req)
     return get_json_result(data=req)
 
@@ -99,7 +99,7 @@ def run():
     if not UserCanvasService.query(user_id=current_user.id, id=req["id"]):
         return get_json_result(
             data=False, message='Only owner of canvas authorized for this operation.',
-            code=settings.RetCode.OPERATING_ERROR)
+            code=RetCode.OPERATING_ERROR)
 
     if not isinstance(cvs.dsl, str):
         cvs.dsl = json.dumps(cvs.dsl, ensure_ascii=False)
@@ -110,26 +110,18 @@ def run():
         canvas = Canvas(cvs.dsl, current_user.id)
         if "message" in req:
             canvas.messages.append({"role": "user", "content": req["message"], "id": message_id})
-            if len([m for m in canvas.messages if m["role"] == "user"]) > 1:
-                # ten = TenantService.get_info_by(current_user.id)[0]
-                # req["message"] = full_question(ten["tenant_id"], ten["llm_id"], canvas.messages)
-                pass
             canvas.add_user_input(req["message"])
-        answer = canvas.run(stream=stream)
-        logging.debug(canvas)
     except Exception as e:
         return server_error_response(e)
 
-    assert answer is not None, "The dialog flow has no way to interact with you. Please add an 'Interact' component to the end of the flow."
-
     if stream:
-        assert isinstance(answer,
-                          partial), "The dialog flow has no way to interact with you. Please add an 'Interact' component to the end of the flow."
-
         def sse():
             nonlocal answer, cvs
             try:
-                for ans in answer():
+                for ans in canvas.run(stream=True):
+                    if ans.get("running_status"):
+                        yield "data:" + json.dumps({"code": 0, "message": "", "data": ans}, ensure_ascii=False) + "\n\n"
+                        continue
                     for k in ans.keys():
                         final_ans[k] = ans[k]
                     ans = {"answer": ans["content"], "reference": ans.get("reference", [])}
@@ -142,6 +134,7 @@ def run():
                 cvs.dsl = json.loads(str(canvas))
                 UserCanvasService.update_by_id(req["id"], cvs.to_dict())
             except Exception as e:
+                traceback.print_exc()
                 yield "data:" + json.dumps({"code": 500, "message": str(e),
                                             "data": {"answer": "**ERROR**: " + str(e), "reference": []}},
                                            ensure_ascii=False) + "\n\n"
@@ -154,13 +147,15 @@ def run():
         resp.headers.add_header("Content-Type", "text/event-stream; charset=utf-8")
         return resp
 
-    final_ans["content"] = "\n".join(answer["content"]) if "content" in answer else ""
-    canvas.messages.append({"role": "assistant", "content": final_ans["content"], "id": message_id})
-    if final_ans.get("reference"):
-        canvas.reference.append(final_ans["reference"])
-    cvs.dsl = json.loads(str(canvas))
-    UserCanvasService.update_by_id(req["id"], cvs.to_dict())
-    return get_json_result(data={"answer": final_ans["content"], "reference": final_ans.get("reference", [])})
+    for answer in canvas.run(stream=False):
+        if answer.get("running_status"): continue
+        final_ans["content"] = "\n".join(answer["content"]) if "content" in answer else ""
+        canvas.messages.append({"role": "assistant", "content": final_ans["content"], "id": message_id})
+        if final_ans.get("reference"):
+            canvas.reference.append(final_ans["reference"])
+        cvs.dsl = json.loads(str(canvas))
+        UserCanvasService.update_by_id(req["id"], cvs.to_dict())
+        return get_json_result(data={"answer": final_ans["content"], "reference": final_ans.get("reference", [])})
 
 
 @manager.route('/reset', methods=['POST'])
@@ -175,7 +170,7 @@ def reset():
         if not UserCanvasService.query(user_id=current_user.id, id=req["id"]):
             return get_json_result(
                 data=False, message='Only owner of canvas authorized for this operation.',
-                code=settings.RetCode.OPERATING_ERROR)
+                code=RetCode.OPERATING_ERROR)
 
         canvas = Canvas(json.dumps(user_canvas.dsl), current_user.id)
         canvas.reset()
diff --git a/api/apps/document_app.py b/api/apps/document_app.py
index 489302238..35dd84ebd 100644
--- a/api/apps/document_app.py
+++ b/api/apps/document_app.py
@@ -563,13 +563,13 @@ def parse():
                 self.filepath = filepath
 
             def read(self):
-                with open(self.filepath, "r") as f:
+                with open(self.filepath, "rb") as f:
                     return f.read()
 
-        r = re.search(r"filename=\"([^\"])\"", json.dumps(res_headers))
-        if not r or r.group(1):
+        r = re.search(r"filename=\"([^\"]+)\"", str(res_headers))
+        if not r or not r.group(1):
             return get_json_result(
-                data=False, message="Can't not identify downloaded file", code=RetCode.ARGUMENT_ERROR)
+                data=False, message="Can't not identify downloaded file", code=settings.RetCode.ARGUMENT_ERROR)
         f = File(r.group(1), os.path.join(download_path, r.group(1)))
         txt = FileService.parse_docs([f], current_user.id)
         return get_json_result(data=txt)
diff --git a/api/db/services/dialog_service.py b/api/db/services/dialog_service.py
index 31f948673..26e23e773 100644
--- a/api/db/services/dialog_service.py
+++ b/api/db/services/dialog_service.py
@@ -98,7 +98,8 @@ def message_fit_in(msg, max_length=4000):
         return c, msg
 
     msg_ = [m for m in msg[:-1] if m["role"] == "system"]
-    msg_.append(msg[-1])
+    if len(msg) > 1:
+        msg_.append(msg[-1])
     msg = msg_
     c = count()
     if c < max_length: