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