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