What causes "feishu image upload: no image_key returned" in sipeed/picoclaw?

Retry the upload once — the condition is typically transient.

feishu image upload: no image_key returned

Error message

feishu image upload: no image_key returned

What it means

The image upload returned Success()==true but Data or Data.ImageKey is nil — an unexpected payload where the API claims success yet delivers no image_key. This is a protocol deviation (gateway quirk or SDK/response-shape mismatch), not a normal input error; there is nothing in the request to fix.

Source

Thrown at pkg/channels/feishu/feishu_64.go:1156

func (c *FeishuChannel) sendImage(ctx context.Context, chatID string, file *os.File) error {
	// Upload image to get image_key
	uploadReq := larkim.NewCreateImageReqBuilder().
		Body(larkim.NewCreateImageReqBodyBuilder().
			ImageType("message").
			Image(file).
			Build()).
		Build()

	uploadResp, err := c.client.Im.V1.Image.Create(ctx, uploadReq)
	if err != nil {
		return fmt.Errorf("feishu image upload: %w", err)
	}
	if !uploadResp.Success() {
		c.invalidateTokenOnAuthError(uploadResp.Code)
		return fmt.Errorf("feishu image upload api error (code=%d msg=%s)", uploadResp.Code, uploadResp.Msg)
	}
	if uploadResp.Data == nil || uploadResp.Data.ImageKey == nil {
		return fmt.Errorf("feishu image upload: no image_key returned")
	}

	imageKey := *uploadResp.Data.ImageKey

	// Send image message
	content, _ := json.Marshal(map[string]string{"image_key": imageKey})
	req := larkim.NewCreateMessageReqBuilder().
		ReceiveIdType(larkim.CreateMessageV1ReceiveIDTypeChatId).
		Body(larkim.NewCreateMessageReqBodyBuilder().
			ReceiveId(chatID).
			MsgType(larkim.MsgTypeImage).
			Content(string(content)).
			Build()).
		Build()

	resp, err := c.client.Im.V1.Message.Create(ctx, req)
	if err != nil {
		return fmt.Errorf("feishu image send: %w", err)

View on GitHub (pinned to 49183d7e8d)

Solutions

Retry the upload once — the condition is typically transient.
Pin/upgrade the lark oapi SDK to a version tested against the current Feishu response schema.
Log the raw response body once to confirm data.image_key is genuinely absent (rules out SDK parsing).
If reproducible, file it with Feishu open-platform support including the request ID.

Defensive patterns

Strategy: retry

Type guard

func isMissingImageKey(err error) bool {
    return strings.Contains(err.Error(), "feishu image upload: no image_key returned")
}

Try / catch

if err := ch.SendMedia(ctx, msg); err != nil {
    if isMissingImageKey(err) {
        // unexpected empty payload: retry once; if it repeats, suspect SDK/API schema drift
    }
}

Prevention

Pin the lark oapi SDK version in go.mod
Retry once on empty-payload errors — they are usually gateway-transient
Log raw upload responses during integration to catch schema drift early

When it happens

Trigger: Im.V1.Image.Create succeeds with an empty data block; occasionally seen under Feishu gateway incidents, or when the vendored lark SDK version deserializes the response shape differently than the live API emits.

Common situations: After upgrading the github.com/larksuite/oapi-sdk-go dependency; during transient Feishu service degradation; region-specific API behavior differences.

Related errors

AI-assisted analysis of sipeed/picoclaw@49183d7e8d (2026-08-15). Data as JSON: /api/errors/2df889dd044d4d3c. Report an issue: GitHub.