Webhook Sink¶
Class: WebhookSinkBlockV1
Source: inference.core.workflows.core_steps.sinks.webhook.v1.WebhookSinkBlockV1
The Webhook Sink block enables sending a data from Workflow into external APIs by sending HTTP requests containing workflow results.
How This Block Works¶
It supports multiple HTTP methods (GET, POST, PUT) and can be configured to send:
-
JSON payloads
-
query parameters
-
multipart-encoded files
This block is designed to provide flexibility for integrating workflows with remote systems for data exchange, notifications, or other integrations.
Setting Query Parameters¶
You can easily set query parameters for your request:
query_parameters = {
"api_key": "$inputs.api_key",
}
will send request into the following URL: https://your-host/some/resource?api_key=<API_KEY_VALUE>
Setting headers¶
Setting headers is as easy as setting query parameters:
headers = {
"api_key": "$inputs.api_key",
}
Sending JSON payloads¶
You can set the body of your message to be JSON document that you construct specifying json_payload
and json_payload_operations properties. json_payload works similarly to query_parameters and
headers, but you can optionally apply UQL operations on top of JSON body elements.
Let's assume that you want to send number of bounding boxes predicted by object detection model
in body field named detections_number, then you need to specify configuration similar to the
following:
json_payload = {
"detections_number": "$steps.model.predictions",
}
json_payload_operations = {
"detections_number": [{"type": "SequenceLength"}]
}
Multipart-Encoded Files in POST requests¶
Your endpoint may also accept multipart requests. You can form them in a way which is similar to
JSON payloads - setting multi_part_encoded_files and multi_part_encoded_files_operations.
Let's assume you want to send the image in the request, then your configuration may be the following:
multi_part_encoded_files = {
"image": "$inputs.image",
}
multi_part_encoded_files_operations = {
"image": [{"type": "ConvertImageToJPEG"}]
}
Cooldown¶
The block accepts cooldown_seconds (which defaults to 5 seconds) to prevent unintended bursts of
notifications. Please adjust it according to your needs, setting 0 indicate no cooldown.
During cooldown period, consecutive runs of the step will cause throttling_status output to be set True
and no notification will be sent.
Cooldown limitations
Current implementation of cooldown is limited to video processing - using this block in context of a
Workflow that is run behind HTTP service (Roboflow Hosted API, Dedicated Deployment or self-hosted
inference server) will have no effect for processing HTTP requests.
Async execution¶
Configure the fire_and_forget property. Set it to True if you want the request to be sent in the background,
allowing the Workflow to proceed without waiting on data to be sent. In this case you will not be able to rely on
error_status output which will always be set to False, so we recommend setting the fire_and_forget=False for
debugging purposes.
Disabling notifications based on runtime parameter¶
Sometimes it would be convenient to manually disable the Webhook sink block. This is possible
setting disable_sink flag to hold reference to Workflow input. with such setup, caller would be
able to disable the sink when needed sending agreed input parameter.
Common Use Cases¶
- Use this block to [purpose based on block type]
Connecting to Other Blocks¶
The outputs from this block can be connected to other blocks in your workflow.
Type identifier¶
Use the following identifier in step "type" field: roboflow_core/webhook_sink@v1to add the block as
as step in your workflow.
Properties¶
| Name | Type | Description | Refs |
|---|---|---|---|
name |
str |
Enter a unique identifier for this step.. | ❌ |
url |
str |
URL of the resource to make request. | ✅ |
method |
str |
HTTP method to be used. | ❌ |
query_parameters |
Dict[str, Union[List[Union[bool, float, int, str]], bool, float, int, str]] |
Request query parameters. | ✅ |
headers |
Dict[str, Union[bool, float, int, str]] |
Request headers. | ✅ |
json_payload |
Dict[str, Union[Dict[Any, Any], List[Any], bool, float, int, str]] |
Fields to put into JSON payload. | ✅ |
json_payload_operations |
Dict[str, List[Union[ClassificationPropertyExtract, ConvertDictionaryToJSON, ConvertImageToBase64, ConvertImageToJPEG, DetectionsFilter, DetectionsOffset, DetectionsPropertyExtract, DetectionsRename, DetectionsSelection, DetectionsShift, DetectionsToDictionary, Divide, ExtractDetectionProperty, ExtractFrameMetadata, ExtractImageProperty, LookupTable, Multiply, NumberRound, NumericSequenceAggregate, PickDetectionsByParentClass, RandomNumber, SequenceAggregate, SequenceApply, SequenceElementsCount, SequenceLength, SequenceMap, SortDetections, StringMatches, StringSubSequence, StringToLowerCase, StringToUpperCase, TimestampToISOFormat, ToBoolean, ToNumber, ToString]]] |
UQL definitions of operations to be performed on defined data w.r.t. each value of json_payload parameter. |
❌ |
multi_part_encoded_files |
Dict[str, Union[Dict[Any, Any], List[Any], bool, float, int, str]] |
Data to POST as Multipart-Encoded File. | ✅ |
multi_part_encoded_files_operations |
Dict[str, List[Union[ClassificationPropertyExtract, ConvertDictionaryToJSON, ConvertImageToBase64, ConvertImageToJPEG, DetectionsFilter, DetectionsOffset, DetectionsPropertyExtract, DetectionsRename, DetectionsSelection, DetectionsShift, DetectionsToDictionary, Divide, ExtractDetectionProperty, ExtractFrameMetadata, ExtractImageProperty, LookupTable, Multiply, NumberRound, NumericSequenceAggregate, PickDetectionsByParentClass, RandomNumber, SequenceAggregate, SequenceApply, SequenceElementsCount, SequenceLength, SequenceMap, SortDetections, StringMatches, StringSubSequence, StringToLowerCase, StringToUpperCase, TimestampToISOFormat, ToBoolean, ToNumber, ToString]]] |
UQL definitions of operations to be performed on defined data w.r.t. each value of multi_part_encoded_files parameter. |
❌ |
form_data |
Dict[str, Union[Dict[Any, Any], List[Any], bool, float, int, str]] |
Fields to put into form-data. | ✅ |
form_data_operations |
Dict[str, List[Union[ClassificationPropertyExtract, ConvertDictionaryToJSON, ConvertImageToBase64, ConvertImageToJPEG, DetectionsFilter, DetectionsOffset, DetectionsPropertyExtract, DetectionsRename, DetectionsSelection, DetectionsShift, DetectionsToDictionary, Divide, ExtractDetectionProperty, ExtractFrameMetadata, ExtractImageProperty, LookupTable, Multiply, NumberRound, NumericSequenceAggregate, PickDetectionsByParentClass, RandomNumber, SequenceAggregate, SequenceApply, SequenceElementsCount, SequenceLength, SequenceMap, SortDetections, StringMatches, StringSubSequence, StringToLowerCase, StringToUpperCase, TimestampToISOFormat, ToBoolean, ToNumber, ToString]]] |
UQL definitions of operations to be performed on defined data w.r.t. each value of form_data parameter. |
❌ |
request_timeout |
int |
Number of seconds to wait for remote API response. | ✅ |
fire_and_forget |
bool |
Boolean flag to run the block asynchronously (True) for faster workflows or synchronously (False) for debugging and error handling.. | ✅ |
disable_sink |
bool |
Boolean flag to disable block execution.. | ✅ |
cooldown_seconds |
int |
Number of seconds to wait until follow-up notification can be sent.. | ✅ |
The Refs column marks possibility to parametrise the property with dynamic values available
in workflow runtime. See Bindings for more info.
Available Connections¶
Compatible Blocks
Check what blocks you can connect to Webhook Sink in version v1.
- inputs:
Motion Detection,Webhook Sink,Qwen2.5-VL,Path Deviation,Slack Notification,Triangle Visualization,Bounding Box Visualization,Stitch Images,Email Notification,Icon Visualization,Anthropic Claude,Mask Area Measurement,Grid Visualization,Heatmap Visualization,Property Definition,Detections Filter,Model Comparison Visualization,Cache Get,Absolute Static Crop,Byte Tracker,Delta Filter,Halo Visualization,Local File Sink,Detections Merge,Stability AI Outpainting,Clip Comparison,Detection Event Log,Dynamic Zone,SAM 3,Time in Zone,Seg Preview,Keypoint Visualization,Roboflow Custom Metadata,Camera Focus,Instance Segmentation Model,Template Matching,Line Counter,Detections Consensus,CLIP Embedding Model,Velocity,Polygon Visualization,VLM As Detector,Time in Zone,Line Counter,Classification Label Visualization,Clip Comparison,Identify Outliers,Polygon Zone Visualization,Relative Static Crop,EasyOCR,Continue If,Detections Transformation,Dimension Collapse,Contrast Equalization,Corner Visualization,SIFT Comparison,CogVLM,Expression,Object Detection Model,Google Vision OCR,Florence-2 Model,Google Gemini,Blur Visualization,Cosine Similarity,JSON Parser,Google Gemini,Multi-Label Classification Model,Roboflow Dataset Upload,Dominant Color,Dot Visualization,Image Contours,SAM 3,First Non Empty Or Default,Stability AI Image Generation,Pixel Color Count,Multi-Label Classification Model,Twilio SMS/MMS Notification,Circle Visualization,Trace Visualization,Object Detection Model,Segment Anything 2 Model,Cache Set,VLM As Detector,Stability AI Inpainting,Buffer,Camera Calibration,Anthropic Claude,LMM,PTZ Tracking (ONVIF).md),Image Preprocessing,Detections Classes Replacement,Stitch OCR Detections,Google Gemini,Detections Stitch,Barcode Detection,LMM For Classification,Morphological Transformation,Bounding Rectangle,Email Notification,OpenAI,Twilio SMS Notification,Distance Measurement,Path Deviation,Perception Encoder Embedding Model,Detections List Roll-Up,Florence-2 Model,OpenAI,VLM As Classifier,SmolVLM2,Background Color Visualization,Anthropic Claude,Camera Focus,Keypoint Detection Model,Mask Visualization,Llama 3.2 Vision,Detection Offset,Byte Tracker,OpenAI,Line Counter Visualization,Single-Label Classification Model,Keypoint Detection Model,SIFT Comparison,Image Convert Grayscale,Detections Stabilizer,Stitch OCR Detections,CSV Formatter,Byte Tracker,Data Aggregator,OCR Model,Roboflow Dataset Upload,Text Display,Time in Zone,Image Slicer,Dynamic Crop,Detections Combine,SIFT,Identify Changes,Halo Visualization,Overlap Filter,Size Measurement,QR Code Generator,Gaze Detection,Image Blur,Instance Segmentation Model,QR Code Detection,Environment Secrets Store,Single-Label Classification Model,VLM As Classifier,Ellipse Visualization,Pixelate Visualization,Reference Path Visualization,Moondream2,YOLO-World Model,Crop Visualization,Rate Limiter,Color Visualization,Qwen3-VL,OpenAI,Polygon Visualization,Image Threshold,Model Monitoring Inference Aggregator,Background Subtraction,Image Slicer,Perspective Correction,Depth Estimation,Label Visualization,SAM 3 - outputs:
Motion Detection,PTZ Tracking (ONVIF).md),Image Preprocessing,Webhook Sink,Detections Classes Replacement,Path Deviation,Stitch OCR Detections,Google Gemini,Triangle Visualization,Slack Notification,Detections Stitch,Bounding Box Visualization,Email Notification,LMM For Classification,Morphological Transformation,Icon Visualization,Anthropic Claude,Heatmap Visualization,Email Notification,Model Comparison Visualization,Twilio SMS Notification,OpenAI,Distance Measurement,Path Deviation,Cache Get,Perception Encoder Embedding Model,Halo Visualization,Local File Sink,OpenAI,Florence-2 Model,Stability AI Outpainting,Dynamic Zone,Time in Zone,SAM 3,Seg Preview,Keypoint Visualization,Roboflow Custom Metadata,Background Color Visualization,Template Matching,Instance Segmentation Model,Line Counter,Detections Consensus,CLIP Embedding Model,Polygon Visualization,Anthropic Claude,Time in Zone,Keypoint Detection Model,Mask Visualization,Llama 3.2 Vision,Line Counter,Classification Label Visualization,OpenAI,Line Counter Visualization,Single-Label Classification Model,Keypoint Detection Model,Clip Comparison,SIFT Comparison,Polygon Zone Visualization,Stitch OCR Detections,Roboflow Dataset Upload,Contrast Equalization,Corner Visualization,Text Display,Time in Zone,Dynamic Crop,CogVLM,Halo Visualization,Object Detection Model,Size Measurement,QR Code Generator,Google Vision OCR,Gaze Detection,Image Blur,Florence-2 Model,Instance Segmentation Model,Google Gemini,Blur Visualization,Google Gemini,Multi-Label Classification Model,Roboflow Dataset Upload,Single-Label Classification Model,Dot Visualization,SAM 3,Stability AI Image Generation,Ellipse Visualization,Pixelate Visualization,Reference Path Visualization,Pixel Color Count,Multi-Label Classification Model,Moondream2,YOLO-World Model,Crop Visualization,Twilio SMS/MMS Notification,Circle Visualization,Trace Visualization,Color Visualization,Object Detection Model,OpenAI,Segment Anything 2 Model,Polygon Visualization,Cache Set,Image Threshold,Model Monitoring Inference Aggregator,Stability AI Inpainting,Perspective Correction,Camera Calibration,Depth Estimation,Label Visualization,Anthropic Claude,LMM,SAM 3
Input and Output Bindings¶
The available connections depend on its binding kinds. Check what binding kinds
Webhook Sink in version v1 has.
Bindings
-
input
url(string): URL of the resource to make request.query_parameters(Union[string,float_zero_to_one,list_of_values,roboflow_api_key,roboflow_project,boolean,roboflow_model_id,integer,top_class,float]): Request query parameters.headers(Union[string,float_zero_to_one,roboflow_api_key,roboflow_project,boolean,roboflow_model_id,integer,top_class,float]): Request headers.json_payload(*): Fields to put into JSON payload.multi_part_encoded_files(*): Data to POST as Multipart-Encoded File.form_data(*): Fields to put into form-data.request_timeout(integer): Number of seconds to wait for remote API response.fire_and_forget(boolean): Boolean flag to run the block asynchronously (True) for faster workflows or synchronously (False) for debugging and error handling..disable_sink(boolean): Boolean flag to disable block execution..cooldown_seconds(integer): Number of seconds to wait until follow-up notification can be sent..
-
output
Example JSON definition of step Webhook Sink in version v1
{
"name": "<your_step_name_here>",
"type": "roboflow_core/webhook_sink@v1",
"url": "<block_does_not_provide_example>",
"method": "<block_does_not_provide_example>",
"query_parameters": {
"api_key": "$inputs.api_key"
},
"headers": {
"api_key": "$inputs.api_key"
},
"json_payload": {
"field": "$steps.model.predictions"
},
"json_payload_operations": {
"predictions": [
{
"property_name": "class_name",
"type": "DetectionsPropertyExtract"
}
]
},
"multi_part_encoded_files": {
"image": "$steps.visualization.image"
},
"multi_part_encoded_files_operations": {
"predictions": [
{
"property_name": "class_name",
"type": "DetectionsPropertyExtract"
}
]
},
"form_data": {
"field": "$inputs.field_value"
},
"form_data_operations": {
"predictions": [
{
"property_name": "class_name",
"type": "DetectionsPropertyExtract"
}
]
},
"request_timeout": "$inputs.request_timeout",
"fire_and_forget": "$inputs.fire_and_forget",
"disable_sink": false,
"cooldown_seconds": "$inputs.cooldown_seconds"
}