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:
Icon Visualization,Instance Segmentation Model,SAM 3,Dynamic Zone,Semantic Segmentation Model,Delta Filter,Relative Static Crop,Image Threshold,Keypoint Visualization,Blur Visualization,Circle Visualization,Detections Merge,Classification Label Visualization,Google Gemini,OpenAI,Identify Outliers,Twilio SMS Notification,CSV Formatter,Model Monitoring Inference Aggregator,Keypoint Detection Model,Path Deviation,Detections Filter,Inner Workflow,Model Comparison Visualization,Byte Tracker,Detections Classes Replacement,Florence-2 Model,Barcode Detection,Grid Visualization,Mask Visualization,Seg Preview,Bounding Rectangle,Qwen3-VL,Detection Event Log,Object Detection Model,Object Detection Model,Detections Stitch,SIFT,Morphological Transformation,Detections Combine,Cache Get,Anthropic Claude,Rate Limiter,Image Slicer,Absolute Static Crop,EasyOCR,Gaze Detection,Color Visualization,Local File Sink,Line Counter,Continue If,Byte Tracker,Mask Area Measurement,OpenAI,Single-Label Classification Model,Clip Comparison,Stitch OCR Detections,Identify Changes,Background Color Visualization,CogVLM,Qwen2.5-VL,Stitch Images,Dominant Color,Contrast Equalization,Velocity,Stability AI Image Generation,Reference Path Visualization,QR Code Detection,Heatmap Visualization,Text Display,VLM As Classifier,Camera Focus,Single-Label Classification Model,Image Preprocessing,SIFT Comparison,Bounding Box Visualization,Background Subtraction,QR Code Generator,Path Deviation,Florence-2 Model,Moondream2,Slack Notification,Label Visualization,Multi-Label Classification Model,Dot Visualization,Camera Calibration,Trace Visualization,Time in Zone,Roboflow Custom Metadata,PTZ Tracking (ONVIF),Overlap Filter,Template Matching,Single-Label Classification Model,Keypoint Detection Model,Crop Visualization,Email Notification,OpenAI,YOLO-World Model,Twilio SMS/MMS Notification,Anthropic Claude,Image Convert Grayscale,Time in Zone,Distance Measurement,Stability AI Inpainting,S3 Sink,Depth Estimation,SAM2 Video Tracker,Motion Detection,Google Gemini,Detections List Roll-Up,CLIP Embedding Model,LMM,Size Measurement,Detection Offset,Dynamic Crop,SAM 3,Perception Encoder Embedding Model,Clip Comparison,SIFT Comparison,Detections Stabilizer,Byte Tracker,Multi-Label Classification Model,VLM As Detector,Property Definition,Polygon Visualization,Webhook Sink,Semantic Segmentation Model,Image Slicer,SORT Tracker,OC-SORT Tracker,OCR Model,GLM-OCR,Roboflow Dataset Upload,Object Detection Model,Polygon Zone Visualization,Instance Segmentation Model,Perspective Correction,SmolVLM2,Cache Set,Data Aggregator,Email Notification,Camera Focus,SAM 3,Polygon Visualization,OpenAI,VLM As Classifier,Stitch OCR Detections,Image Contours,Roboflow Vision Events,Llama 3.2 Vision,First Non Empty Or Default,VLM As Detector,Instance Segmentation Model,Cosine Similarity,JSON Parser,Time in Zone,LMM For Classification,Pixel Color Count,Triangle Visualization,Expression,Line Counter,Qwen3.5-VL,Anthropic Claude,Image Blur,Corner Visualization,Halo Visualization,Detections Consensus,Buffer,Line Counter Visualization,Multi-Label Classification Model,ByteTrack Tracker,Keypoint Detection Model,Roboflow Dataset Upload,Segment Anything 2 Model,Detections Transformation,Environment Secrets Store,Stability AI Outpainting,Halo Visualization,Dimension Collapse,Pixelate Visualization,Google Vision OCR,Ellipse Visualization,Google Gemini - outputs:
Icon Visualization,Moondream2,Slack Notification,Label Visualization,Instance Segmentation Model,Multi-Label Classification Model,Dot Visualization,Camera Calibration,Trace Visualization,SAM 3,Time in Zone,Roboflow Custom Metadata,Dynamic Zone,Semantic Segmentation Model,Image Threshold,Keypoint Visualization,PTZ Tracking (ONVIF),Template Matching,Single-Label Classification Model,Path Deviation,Blur Visualization,Circle Visualization,Keypoint Detection Model,Crop Visualization,Email Notification,Classification Label Visualization,OpenAI,Google Gemini,OpenAI,Twilio SMS Notification,YOLO-World Model,Twilio SMS/MMS Notification,Keypoint Detection Model,Model Monitoring Inference Aggregator,Anthropic Claude,Path Deviation,Google Gemini,Time in Zone,Distance Measurement,Stability AI Inpainting,S3 Sink,Depth Estimation,Model Comparison Visualization,Motion Detection,Google Gemini,Detections Classes Replacement,CLIP Embedding Model,Florence-2 Model,Size Measurement,LMM,Dynamic Crop,SAM 3,Perception Encoder Embedding Model,Multi-Label Classification Model,Polygon Visualization,Webhook Sink,Seg Preview,Object Detection Model,Object Detection Model,GLM-OCR,Roboflow Dataset Upload,Object Detection Model,Polygon Zone Visualization,Detections Stitch,Morphological Transformation,Perspective Correction,Instance Segmentation Model,Florence-2 Model,Cache Get,Anthropic Claude,Cache Set,Email Notification,SAM 3,Gaze Detection,Polygon Visualization,OpenAI,Stitch OCR Detections,Color Visualization,Local File Sink,Line Counter,Roboflow Vision Events,OpenAI,Single-Label Classification Model,Llama 3.2 Vision,Clip Comparison,Instance Segmentation Model,Time in Zone,Triangle Visualization,LMM For Classification,Pixel Color Count,Background Color Visualization,Stitch OCR Detections,Line Counter,CogVLM,Anthropic Claude,Image Blur,Contrast Equalization,Corner Visualization,Halo Visualization,Stability AI Image Generation,Detections Consensus,Reference Path Visualization,Line Counter Visualization,Multi-Label Classification Model,Keypoint Detection Model,Roboflow Dataset Upload,Heatmap Visualization,Text Display,Segment Anything 2 Model,Single-Label Classification Model,Image Preprocessing,SIFT Comparison,Bounding Box Visualization,Stability AI Outpainting,Halo Visualization,QR Code Generator,Pixelate Visualization,Ellipse Visualization,Google Vision OCR,Mask 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[float_zero_to_one,roboflow_model_id,float,roboflow_project,top_class,list_of_values,integer,roboflow_api_key,string,boolean]): Request query parameters.headers(Union[float_zero_to_one,roboflow_model_id,float,roboflow_project,top_class,integer,roboflow_api_key,string,boolean]): 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"
}