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:
Barcode Detection,Roboflow Custom Metadata,Pixelate Visualization,Halo Visualization,Delta Filter,Halo Visualization,Ellipse Visualization,Image Slicer,Byte Tracker,OCR Model,Anthropic Claude,Clip Comparison,Stability AI Inpainting,Stitch OCR Detections,QR Code Generator,JSON Parser,Object Detection Model,Qwen3-VL,SIFT,Path Deviation,Detections Stitch,PTZ Tracking (ONVIF),Slack Notification,Keypoint Detection Model,First Non Empty Or Default,Expression,Single-Label Classification Model,Relative Static Crop,Identify Changes,Crop Visualization,Motion Detection,Environment Secrets Store,Llama 3.2 Vision,Camera Focus,Line Counter Visualization,Morphological Transformation,Line Counter,Time in Zone,Buffer,Pixel Color Count,Polygon Visualization,Contrast Equalization,Model Monitoring Inference Aggregator,Local File Sink,Detection Event Log,Corner Visualization,Model Comparison Visualization,Text Display,Moondream2,Roboflow Dataset Upload,Reference Path Visualization,Cosine Similarity,Image Slicer,Icon Visualization,Absolute Static Crop,Label Visualization,Image Preprocessing,Classification Label Visualization,Mask Visualization,Single-Label Classification Model,VLM As Classifier,Bounding Box Visualization,Byte Tracker,Mask Area Measurement,Triangle Visualization,Email Notification,QR Code Detection,Anthropic Claude,Instance Segmentation Model,Stitch OCR Detections,Email Notification,Property Definition,Seg Preview,Florence-2 Model,Background Subtraction,Bounding Rectangle,SAM 3,VLM As Detector,Detections Classes Replacement,Blur Visualization,Detections Transformation,SAM 3,Multi-Label Classification Model,Polygon Visualization,Anthropic Claude,OpenAI,Webhook Sink,Dynamic Crop,Image Convert Grayscale,Circle Visualization,Florence-2 Model,Stability AI Outpainting,Dynamic Zone,Detections Combine,EasyOCR,Time in Zone,Size Measurement,Twilio SMS Notification,SIFT Comparison,VLM As Classifier,Image Blur,OpenAI,Line Counter,Dominant Color,YOLO-World Model,Detections Filter,Detection Offset,Dimension Collapse,Detections List Roll-Up,Perception Encoder Embedding Model,Segment Anything 2 Model,LMM,Cache Get,Image Threshold,Overlap Filter,Detections Merge,Keypoint Detection Model,Template Matching,Stitch Images,Perspective Correction,Color Visualization,Google Gemini,SAM 3,Identify Outliers,OpenAI,Continue If,Google Gemini,Roboflow Dataset Upload,Object Detection Model,Heatmap Visualization,Time in Zone,Distance Measurement,Trace Visualization,Grid Visualization,Data Aggregator,Polygon Zone Visualization,Rate Limiter,Keypoint Visualization,Google Vision OCR,Qwen2.5-VL,Detections Stabilizer,CogVLM,Instance Segmentation Model,LMM For Classification,VLM As Detector,SmolVLM2,Background Color Visualization,Google Gemini,Detections Consensus,OpenAI,Dot Visualization,Twilio SMS/MMS Notification,Image Contours,Byte Tracker,Camera Calibration,Multi-Label Classification Model,Clip Comparison,Gaze Detection,Velocity,Path Deviation,CSV Formatter,Camera Focus,SIFT Comparison,CLIP Embedding Model,Qwen3.5-VL,Cache Set,Stability AI Image Generation,Depth Estimation - outputs:
Pixelate Visualization,Roboflow Custom Metadata,Halo Visualization,Anthropic Claude,OpenAI,Halo Visualization,Ellipse Visualization,Webhook Sink,Dynamic Crop,Circle Visualization,Florence-2 Model,Stability AI Outpainting,Dynamic Zone,Anthropic Claude,Size Measurement,Twilio SMS Notification,Stability AI Inpainting,SIFT Comparison,Stitch OCR Detections,Image Blur,QR Code Generator,Object Detection Model,OpenAI,Path Deviation,Line Counter,Detections Stitch,YOLO-World Model,PTZ Tracking (ONVIF),Slack Notification,Keypoint Detection Model,Perception Encoder Embedding Model,Segment Anything 2 Model,LMM,Cache Get,Image Threshold,Single-Label Classification Model,Keypoint Detection Model,Crop Visualization,Template Matching,Perspective Correction,Motion Detection,Line Counter Visualization,Llama 3.2 Vision,Color Visualization,Morphological Transformation,Google Gemini,Line Counter,Time in Zone,SAM 3,Pixel Color Count,OpenAI,Roboflow Dataset Upload,Google Gemini,Object Detection Model,Polygon Visualization,Heatmap Visualization,Time in Zone,Distance Measurement,Contrast Equalization,Trace Visualization,Model Monitoring Inference Aggregator,Local File Sink,Corner Visualization,Polygon Zone Visualization,Model Comparison Visualization,Keypoint Visualization,Text Display,Google Vision OCR,Moondream2,Roboflow Dataset Upload,Cache Set,Reference Path Visualization,CogVLM,Instance Segmentation Model,LMM For Classification,Icon Visualization,Background Color Visualization,Google Gemini,Classification Label Visualization,Label Visualization,Image Preprocessing,Mask Visualization,Single-Label Classification Model,Detections Consensus,Bounding Box Visualization,OpenAI,Triangle Visualization,Dot Visualization,Email Notification,Twilio SMS/MMS Notification,Anthropic Claude,Instance Segmentation Model,Email Notification,Seg Preview,Stitch OCR Detections,Florence-2 Model,SAM 3,Camera Calibration,Multi-Label Classification Model,Clip Comparison,Gaze Detection,Detections Classes Replacement,Blur Visualization,Path Deviation,SAM 3,Multi-Label Classification Model,CLIP Embedding Model,Time in Zone,Stability AI Image Generation,Depth Estimation,Polygon Visualization
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[roboflow_api_key,boolean,roboflow_project,roboflow_model_id,integer,float_zero_to_one,list_of_values,float,string,top_class]): Request query parameters.headers(Union[roboflow_api_key,boolean,roboflow_project,roboflow_model_id,integer,float_zero_to_one,float,string,top_class]): 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"
}