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