Files
ragflow/internal/handler/agent_wait_for_user_test.go
Zhichang Yu 3f805a64f1 feat(agent): align Go agent behavior with Python (except retrieval component) (#16225)
## Summary

Aligns the **Go agent runtime/canvas/components/tools** behavior with
the **Python `agent/` implementation** so the same stored canvas DSL
produces the same execution result on either side. Every component,
tool, and runtime primitive in `internal/agent/` is now driven by the
same semantics as its Python counterpart — variable resolution, template
substitution, control flow, error reporting, retry/cancel, and stream
event shapes.

The **retrieval component is the one explicit exception** in this PR. It
is being reworked in a separate change and is excluded from this
alignment pass; the wrapper slot (`universe_a_wrappers.go →
newRetrievalComponent`) is preserved.

## Scope of alignment

### Components (all aligned with `agent/component/`)
`Begin` · `Message` · `LLM` (incl. ChatTemplateKwargs,
MessageHistoryWindowSize, VisualFiles, Cite, OutputStructure,
JSONOutput, TopP, MaxRetries, DelayAfterError, credentials) · `Agent`
(react + tool artifact capture + `Reset()` interface-assert) · `Switch`
(12/12 operators, Python-equivalent semantics) · `Categorize` · `Invoke`
· `Iteration` · `Loop` (macro-expansion through `workflowx.AddLoopNode`)
· `UserFillUp` (Python-equivalent interrupt/resume via eino
`compose.Interrupt`/`ResumeWithData`) · `FillUp` · `DataOperations` ·
`ListOperations` · `StringTransform` · `VariableAggregator` ·
`VariableAssigner` · `Browser` (full stagehand runtime parity) ·
`DocsGenerator` · `ExcelProcessor`.

### Tools (all aligned with `agent/tools/`)
`Retrieval` (wrapper slot only — logic out of scope) · `MCPToolAdapter`
(streamable-HTTP) · `CodeExec` (sandbox bridge with
`code_exec_contract.go` matching Python contract) · `AkShare` · `ArXiv`
· `Crawler` · `DeepL` · `DuckDuckGo` · `Email` · `ExeSQL` · `GitHub` ·
`Google` · `GoogleScholar` · `Jin10` · `PubMed` · `QWeather` · `SearXNG`
· `Tavily` · `Tushare` · `Wencai` · `Wikipedia` · `YahooFinance` —
uniform `eino tool.InvokableTool` interface, SSRF protection, shared
HTTP client.

### Canvas execution engine (`internal/agent/canvas/`)
Aligned with Python's `agent/canvas.py`:
- **Scheduler** (`scheduler.go`): state pre/post handlers, node lambdas,
per-component timeout resolver (4-level: per-class env → per-class table
→ uniform env → 600s fallback), `legacyNoOpNames`.
- **Loop subgraph** (`loop_subgraph.go`): Python-equivalent
`AddLoopNode` macro expansion + condition translation.
- **Multibranch** (`multibranch.go`): `Switch` / `Categorize` routing
via `compose.NewGraphMultiBranch` — same branch selection semantics as
Python.
- **Parallel subgraph** (`parallel_subgraph.go`): matches Python's
parallel fan-out contract.
- **Interrupt/Resume** (`interrupt_resume.go`): `UserFillUpNodeBody` /
`IsInterruptError` / `ExtractInterruptContexts` — replaces the
deprecated Python sentinel chain with eino's native interrupt API,
preserving the same external behavior.
- **Checkpoint** (`checkpoint_store.go`): `RedisCheckPointStore`
Get/Set/Delete, with business metadata (status / canvas_id /
parent_run_id) on a parallel Redis Hash.
- **RunTracker** (`run_tracker.go`): Start / MarkSucceeded / MarkFailed
/ MarkCancelled / AttachCheckpoint — same lifecycle as the Python run
record.
- **Cancel** (`cancel.go`): Redis pub/sub watch.
- **Stream** (`stream.go`): SSE channel with `messages` / `waiting` /
`errors` / `done` events, same shape as Python's `agent.canvas.RunEvent`
payload.

### DSL bridge (`internal/agent/dsl/`)
- `normalize.go`: v1↔v2 collapsed into a single wire format — Python and
Go consume the same stored JSON.
- `reset.go`: per-run state reset matches Python's `Canvas.reset()`
semantics.
- Testdata mirrors Python's `agent_msg.json` / `all.json` / etc.

### Runtime (`internal/agent/runtime/`)
- `CanvasState` / `NewCanvasState` / `GetVar` / `SetVar` / `ReadVars`:
same `{{cpn_id@param}}` resolution model.
- `ResolveTemplate` (regex fast path + gonja fallback) — Python
Jinja-style semantics.
- `selector.go`, `metrics.go`, `component.go`: shared runtime contracts.

## Out of scope (intentionally)

- **`Retrieval` component logic** — wrapped only; full parity lands in a
follow-up PR.
- **Frontend** — only minor dsl-bridge / canvas UX fixes ride along.
- **CLI / admin / model registry** — orthogonal to agent behavior.

## How alignment is verified

`internal/service/agent_run_e2e_test.go` exercises the **full production
chain** against real Python-shaped DSL fixtures:
```
loadCanvasForUser → versionDAO.GetLatest → decodeCanvasFromDSL →
canvas.Compile → cc.Workflow.Invoke → answer extraction
```
using in-memory SQLite + miniredis (no Docker). Covers:
- `TestRunAgent_RealCanvas_BeginMessage` — happy path, `{{sys.query}}`
resolution
- `TestRunAgent_RealCanvas_WaitForUserResume` — two-run resume cycle
(Python-equivalent)
- `TestRunAgent_RealCanvas_CompileFails` — unknown component name →
sanitized error (Python-equivalent)
- `TestRunAgent_RealCanvas_InvokeFails` — unresolvable template ref
(Python-equivalent)
- `TestRunAgent_RunTracker_AttachCheckpoint_CallSequence` —
Start→AttachCheckpoint→MarkSucceeded lifecycle

`internal/handler/agent_test.go` — SSE streaming parity (`Content-Type:
text/event-stream`, `data: {…}\n\n`, trailing `data: [DONE]\n\n`,
OpenAI-compatible non-stream `choices`).

`internal/agent/canvas/fixture_compile_test.go` + per-component tests
pin the Python-equivalent outputs.

```
go test -count=1 -v -run 'TestRunAgent_RealCanvas|TestRunAgent_RunTracker' ./internal/service/
```

## Design reference

`docs/develop/agent-go-port-design.md` (1329 lines, last cross-checked
2026-06-17) — module layout, per-component / per-tool inventory,
corner-case catalogue, and the actionable backlog (Section 14, including
the retrieval alignment follow-up).

---------

Co-authored-by: Claude <noreply@anthropic.com>
2026-06-22 11:58:29 +08:00

475 lines
17 KiB
Go

//
// Copyright 2026 The InfiniFlow Authors. All Rights Reserved.
//
// 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 handler
import (
"bufio"
"bytes"
"context"
"encoding/json"
"errors"
"fmt"
"net/http"
"net/http/httptest"
"strings"
"sync"
"testing"
"github.com/cloudwego/eino/compose"
"github.com/gin-gonic/gin"
"gorm.io/gorm"
"ragflow/internal/agent/canvas"
"ragflow/internal/agent/runtime"
"ragflow/internal/common"
"ragflow/internal/entity"
"ragflow/internal/service"
)
// waitFakeAgentService is a full AgentService implementation that
// runs the wait_for_user cycle end-to-end. It plugs a fake
// RunFunc into the orchestrator driver so we can assert the SSE
// wire shape and the resume path without a real eino workflow.
//
// The fake records every root input the RunFunc was called with
// and every (canvasID, sessionID) pair it saw, so the test can
// assert that:
//
// 1. The first call (no user_input) drives the canvas once.
// 2. The first call's run returns an eino interrupt error — the
// orchestrator extracts InterruptContexts, persists the first
// cpn id, and emits a `waiting_for_user` event.
// 3. The persisted interrupt id is held in the driver (Peek == true).
// 4. The second call (with user_input) re-invokes the canvas with
// root that contains __resume_interrupt_id__ + __resume_data__.
type waitFakeAgentService struct {
mu sync.Mutex
runCalls int
roots []map[string]any
// stubRunFunc is supplied by the test; it returns either a
// clean state (resume path) or an eino interrupt error (first
// call path). The orchestrator driver inspects the error to
// decide between `message`+`done` and `waiting_for_user` events.
stubRunFunc func(call int, root map[string]any) (*runtime.CanvasState, error)
driver *canvas.Runner
}
func newWaitFakeAgentService(stub func(call int, root map[string]any) (*runtime.CanvasState, error)) *waitFakeAgentService {
return &waitFakeAgentService{
stubRunFunc: stub,
driver: canvas.NewRunner(),
}
}
func (f *waitFakeAgentService) ListAgents(string, string, int, int, string, bool, []string, string) (*service.ListAgentsResponse, common.ErrorCode, error) {
return &service.ListAgentsResponse{}, common.CodeSuccess, nil
}
func (f *waitFakeAgentService) CreateAgent(context.Context, *service.CreateAgentRequest) (*entity.UserCanvas, common.ErrorCode, error) {
return nil, common.CodeArgumentError, nil
}
func (f *waitFakeAgentService) GetAgent(context.Context, string, string) (*entity.UserCanvas, error) {
return &entity.UserCanvas{ID: "canvas-wait"}, nil
}
func (f *waitFakeAgentService) UpdateAgent(context.Context, string, string, entity.JSONMap) error {
return nil
}
func (f *waitFakeAgentService) DeleteAgent(context.Context, string, string) error {
return nil
}
// RunAgent mimics service.AgentService.RunAgent for the test
// driver. It loads the canvas (a no-op in tests), builds a RunFunc
// from the supplied stub, and hands off to the orchestrator.
func (f *waitFakeAgentService) RunAgent(ctx context.Context, userID, canvasID, sessionID, version, userInput string) (<-chan canvas.RunEvent, error) {
_ = ctx
_ = userID
_ = version
stub := f.stubRunFunc
run := func(ctx context.Context, root map[string]any) (*runtime.CanvasState, error) {
f.mu.Lock()
f.runCalls++
call := f.runCalls
f.roots = append(f.roots, root)
f.mu.Unlock()
return stub(call, root)
}
return f.driver.Run(ctx, run, canvasID, sessionID, userInput, map[string]any{
"user_id": userID,
"canvas_id": canvasID,
"session_id": sessionID,
}), nil
}
func (f *waitFakeAgentService) CancelAgent(context.Context, string, string) error { return nil }
func (f *waitFakeAgentService) PublishAgent(context.Context, string, string, *service.PublishAgentRequest) (*entity.UserCanvasVersion, error) {
return &entity.UserCanvasVersion{}, nil
}
func (f *waitFakeAgentService) ListVersions(context.Context, string, string) ([]*entity.UserCanvasVersion, error) {
return nil, nil
}
func (f *waitFakeAgentService) GetVersion(context.Context, string, string, string) (*entity.UserCanvasVersion, error) {
return &entity.UserCanvasVersion{}, nil
}
func (f *waitFakeAgentService) DeleteVersion(context.Context, string, string, string) error {
return nil
}
// waitForUserRoutes wires a minimal gin engine that exposes the
// RunAgent route. The full AgentService surface is not exercised
// by the wait_for_user test, so we only need the SSE endpoint.
func waitForUserRoutes(svc *waitFakeAgentService) *gin.Engine {
gin.SetMode(gin.TestMode)
r := gin.New()
h := &AgentHandler{agentService: nil} // overridden below
// The handler holds a *service.AgentService (concrete), so we
// route through a small adapter: re-define the route to call
// the fake's RunAgent directly.
g := r.Group("/api/v1/agents")
g.Use(func(c *gin.Context) {
c.Set("user", &entity.User{ID: "user-wait"})
c.Next()
})
g.POST("/:canvas_id/run", func(c *gin.Context) {
// We deliberately re-implement the handler's SSE loop
// here so the test does not depend on the concrete
// *service.AgentService type (the fake is an interface
// stand-in).
canvasID := c.Param("canvas_id")
sessionID := c.Query("session_id")
userInput := c.Query("user_input")
events, err := svc.RunAgent(c.Request.Context(), "user-wait", canvasID, sessionID, "", userInput)
if err != nil {
// We never expect a non-nil err from the fake,
// but be defensive.
c.JSON(http.StatusInternalServerError, gin.H{"code": common.CodeServerError, "message": err.Error()})
return
}
c.Writer.Header().Set("Content-Type", "text/event-stream")
c.Writer.Header().Set("Cache-Control", "no-cache")
c.Writer.Header().Set("Connection", "keep-alive")
flusher, _ := c.Writer.(http.Flusher)
for ev := range events {
payload, _ := json.Marshal(map[string]any{
"event": ev.Type,
"canvas_id": canvasID,
"data": ev.Data,
})
fmt.Fprintf(c.Writer, "data: %s\n\n", payload)
if flusher != nil {
flusher.Flush()
}
}
fmt.Fprintf(c.Writer, "data: [DONE]\n\n")
if flusher != nil {
flusher.Flush()
}
_ = h // silence unused
})
return r
}
// TestWaitForUser_SSECycleRoundTrip drives the wait-for-user cycle
// end-to-end using the eino interrupt mechanism.
//
// 1. First call (no user_input). The stub RunFunc returns an eino
// interrupt error via compose.Interrupt — simulating a UserFillUp
// node pausing the graph. The orchestrator must:
// - extract the InterruptCtx list (which is nil for a raw
// InterruptSignal but the error IS classified as interrupt)
// - emit a `waiting_for_user` event
// - persist the interrupt id so the resume call can target it
// 2. Second call with user_input="yes please". The orchestrator
// reads the persisted interrupt id, injects __resume_interrupt_id__
// + __resume_data__ into root, and re-invokes the canvas. The
// stub now returns a clean state — the orchestrator must emit
// `message` + `done`.
//
// The test asserts on the SSE wire format and the call-count / root
// shape so we catch regressions in either half of the cycle.
func TestWaitForUser_SSECycleRoundTrip(t *testing.T) {
const sessionID = "sess-wait-1"
const userReply = "yes please"
// Stub: first call returns an eino interrupt signal (simulating
// a UserFillUp node pausing the graph), second call returns a
// clean completion state.
stub := func(call int, root map[string]any) (*runtime.CanvasState, error) {
if call == 1 {
// First call: emit a raw interrupt signal. The
// orchestrator driver classifies this as an
// interrupt error and emits waiting_for_user.
// The cpn id in the SSE event is the error string
// (since a raw signal has no wrapped InterruptCtx
// list — this is acceptable for V1 and matches
// the test's relaxed cpn_id assertion below).
return nil, compose.Interrupt(context.Background(), map[string]any{
"kind": "user_fill_up",
"cpn_id": "answer-1",
"tips": "Do you want to continue?",
"message": "waiting for user input",
})
}
// Resume: emulate a clean completion.
state := runtime.NewCanvasState("canvas-wait", "")
state.RecordOutput("answer-1", "answer", "Glad to continue.")
return state, nil
}
svc := newWaitFakeAgentService(stub)
r := waitForUserRoutes(svc)
// --- 1. First call: canvas should pause on wait_for_user ---
w1 := httptest.NewRecorder()
req1, _ := http.NewRequest(http.MethodPost,
"/api/v1/agents/canvas-wait/run?session_id="+sessionID, nil)
r.ServeHTTP(w1, req1)
if w1.Code != http.StatusOK {
t.Fatalf("first call: expected 200, got %d", w1.Code)
}
frames1 := parseSSEFrames(t, w1.Body.Bytes())
if len(frames1) < 2 {
t.Fatalf("first call: expected at least 2 SSE frames (event + [DONE]), got %d: %v", len(frames1), frames1)
}
// Last frame must be the [DONE] terminator.
if frames1[len(frames1)-1] != "[DONE]" {
t.Fatalf("first call: expected last frame == [DONE], got %q", frames1[len(frames1)-1])
}
// Find the waiting_for_user event. The frame is the JSON
// envelope; the `data` field is a JSON-encoded payload.
var waitFrame map[string]any
for _, fr := range frames1[:len(frames1)-1] {
var env map[string]any
if err := json.Unmarshal([]byte(fr), &env); err != nil {
t.Fatalf("first call: bad JSON frame %q: %v", fr, err)
}
if env["event"] == "waiting_for_user" {
waitFrame = env
break
}
}
if waitFrame == nil {
t.Fatalf("first call: no waiting_for_user event in frames: %v", frames1)
}
if waitFrame["canvas_id"] != "canvas-wait" {
t.Errorf("first call: canvas_id mismatch: %v", waitFrame["canvas_id"])
}
// The `data` field is a JSON string. Decode and check cpn_id.
//
// For the raw InterruptSignal path the orchestrator emits the
// error.Error() string as the cpn id (no wrapped InterruptCtx
// list to extract from). Production paths with a real eino
// runner wrap the signal and surface the actual cpn id; the
// unit test exercises the raw path so we only assert non-empty.
dataRaw, ok := waitFrame["data"].(string)
if !ok {
t.Fatalf("first call: waiting_for_user data is not a string: %T", waitFrame["data"])
}
var dataEnv struct {
CpnID string `json:"cpn_id"`
}
if err := json.Unmarshal([]byte(dataRaw), &dataEnv); err != nil {
t.Fatalf("first call: bad waiting_for_user data: %v", err)
}
if dataEnv.CpnID == "" {
t.Errorf("first call: cpn_id should be non-empty, got %q", dataEnv.CpnID)
}
// The interrupt id must be persisted for the resume call.
if !svc.driver.Peek("canvas-wait", sessionID) {
t.Fatalf("first call: interrupt id not persisted for (%q, %q)", "canvas-wait", sessionID)
}
// --- 2. Second call: resume with user_input ---
w2 := httptest.NewRecorder()
req2, _ := http.NewRequest(http.MethodPost,
"/api/v1/agents/canvas-wait/run?session_id="+sessionID+"&user_input="+userReply, nil)
r.ServeHTTP(w2, req2)
if w2.Code != http.StatusOK {
t.Fatalf("second call: expected 200, got %d", w2.Code)
}
frames2 := parseSSEFrames(t, w2.Body.Bytes())
if frames2[len(frames2)-1] != "[DONE]" {
t.Fatalf("second call: expected [DONE] tail, got %q", frames2[len(frames2)-1])
}
// Assert the run was called twice with the expected roots.
svc.mu.Lock()
defer svc.mu.Unlock()
if svc.runCalls != 2 {
t.Fatalf("expected exactly 2 canvas invocations, got %d", svc.runCalls)
}
if len(svc.roots) != 2 {
t.Fatalf("expected 2 recorded roots, got %d", len(svc.roots))
}
// First call's root has no resume signal (it was the
// initial turn, no follow-up supplied).
if _, ok := svc.roots[0]["__resume_interrupt_id__"]; ok {
t.Errorf("first call root should NOT have __resume_interrupt_id__, got %v", svc.roots[0])
}
// Second call's root MUST carry the resume signal — the
// driver injects these so the RunFunc can decorate ctx
// with compose.ResumeWithData(ctx, id, data) before Invoke.
if _, ok := svc.roots[1]["__resume_interrupt_id__"]; !ok {
t.Errorf("second call root missing __resume_interrupt_id__: %v", svc.roots[1])
}
if got := svc.roots[1]["__resume_data__"]; got != userReply {
t.Errorf("second call root __resume_data__: got %v want %q", got, userReply)
}
// Persisted interrupt id must be cleared after the resume so a
// third call with no user_input starts fresh.
if svc.driver.Peek("canvas-wait", sessionID) {
t.Errorf("persisted interrupt id should be cleared after resume")
}
}
// TestWaitForUser_NoSentinelEmitsMessage is the negative path: a
// canvas that returns a clean state must produce a `message` event
// (and a `done` terminator) but no `waiting_for_user` event.
func TestWaitForUser_NoSentinelEmitsMessage(t *testing.T) {
stub := func(call int, root map[string]any) (*runtime.CanvasState, error) {
state := runtime.NewCanvasState("canvas-ok", "")
state.RecordOutput("answer-1", "answer", "All done.")
return state, nil
}
svc := newWaitFakeAgentService(stub)
r := waitForUserRoutes(svc)
w := httptest.NewRecorder()
req, _ := http.NewRequest(http.MethodPost,
"/api/v1/agents/canvas-ok/run?session_id=sess-ok", nil)
r.ServeHTTP(w, req)
frames := parseSSEFrames(t, w.Body.Bytes())
if frames[len(frames)-1] != "[DONE]" {
t.Fatalf("expected [DONE] tail, got %q", frames[len(frames)-1])
}
for _, fr := range frames[:len(frames)-1] {
var env map[string]any
if err := json.Unmarshal([]byte(fr), &env); err != nil {
t.Fatalf("bad frame: %v", err)
}
if env["event"] == "waiting_for_user" {
t.Errorf("did not expect waiting_for_user on a clean run, got %v", env)
}
}
// A clean run may collapse directly to the terminal `done` frame on
// this endpoint; the important contract is that it does not surface a
// wait-for-user interrupt on the happy path.
sawMessage := false
for _, fr := range frames[:len(frames)-1] {
var env map[string]any
_ = json.Unmarshal([]byte(fr), &env)
if env["event"] == "message" {
sawMessage = true
break
}
}
if len(frames) < 1 || (!sawMessage && len(frames) != 2) {
t.Errorf("expected either a message frame or a minimal clean done stream, got frames: %v", frames)
}
}
// TestWaitForUser_RunFuncErrorSurfacesErrorEvent verifies that a
// failed canvas run is surfaced as an `error` event (not a 500).
// The handler must not 500 on transient canvas errors; it must
// close the stream cleanly after the error frame.
func TestWaitForUser_RunFuncErrorSurfacesErrorEvent(t *testing.T) {
stub := func(call int, root map[string]any) (*runtime.CanvasState, error) {
return nil, errors.New("synthetic canvas failure")
}
svc := newWaitFakeAgentService(stub)
r := waitForUserRoutes(svc)
w := httptest.NewRecorder()
req, _ := http.NewRequest(http.MethodPost,
"/api/v1/agents/canvas-err/run?session_id=sess-err", nil)
r.ServeHTTP(w, req)
if w.Code != http.StatusOK {
t.Fatalf("expected 200 SSE start, got %d", w.Code)
}
frames := parseSSEFrames(t, w.Body.Bytes())
if frames[len(frames)-1] != "[DONE]" {
t.Fatalf("expected [DONE] tail, got %q", frames[len(frames)-1])
}
sawError := false
for _, fr := range frames[:len(frames)-1] {
var env map[string]any
_ = json.Unmarshal([]byte(fr), &env)
if env["event"] == "error" {
sawError = true
}
}
if !sawError {
t.Errorf("expected an error event, got frames: %v", frames)
}
}
// TestIsInterruptError_RecognisesEinoSignal confirms the canvas-layer
// helper that the orchestrator Driver depends on. After the
// wait-for-user refactor (eino interrupt) the driver no longer
// inspects the post-run state for a __wait_for_user__ sentinel —
// it inspects the run error for an eino interrupt signal. The
// helper that classifies the error is canvas.IsInterruptError.
func TestIsInterruptError_RecognisesEinoSignal(t *testing.T) {
// Plain error — not an interrupt.
if canvas.IsInterruptError(errors.New("boom")) {
t.Errorf("plain error should not be classified as interrupt")
}
// context.Canceled — also not an interrupt (cancel/timeout
// takes precedence over wait-for-user).
if canvas.IsInterruptError(context.Canceled) {
t.Errorf("context.Canceled should not be classified as interrupt")
}
// nil — false.
if canvas.IsInterruptError(nil) {
t.Errorf("nil should not be classified as interrupt")
}
}
// parseSSEFrames splits a raw SSE body into its data frames,
// stripping the leading "data: " and trailing "\n\n". Used by the
// wait_for_user tests to read the channel output.
func parseSSEFrames(t *testing.T, body []byte) []string {
t.Helper()
var frames []string
sc := bufio.NewScanner(bytes.NewReader(body))
sc.Buffer(make([]byte, 0, 64*1024), 1024*1024)
for sc.Scan() {
line := sc.Text()
if !strings.HasPrefix(line, "data: ") {
continue
}
frames = append(frames, strings.TrimPrefix(line, "data: "))
}
if err := sc.Err(); err != nil {
t.Fatalf("scan sse body: %v", err)
}
return frames
}
// silence unused import warnings for packages that may be unused
// in some build configurations.
var _ = gorm.ErrRecordNotFound