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Send Signal

POST /api/signals/send

Sends a signal to an existing data source.

Tip

Step-by-step guide with complete code examples: Import Data from Python & MATLAB

Request

POST /api/signals/send HTTP/1.1
Host: localhost:5678
Content-Type: application/json

JSON Inline

Body Parameters

Parameter	Type	Required	Description
`name`	string	Yes	Signal name
`y`	array	Yes	Y values (amplitude)
`x`	array	No	X values (time/frequency). Auto-generated if not provided
`z`	array/2D-array	No	Z values for trace lines (1D) or spectrograms (2D)
`y_unit`	string	No	Unit of the Y axis (e.g. `"V"`, `"A"`)
`x_unit`	string	No	Unit of the X axis (e.g. `"s"`, `"Hz"`)
`z_unit`	string	No	Unit of the Z axis (e.g. `"dB"`, `"°C"`)
`target_source_id`	string	Yes	ID of the target data source

Example: Simple Signal

{
  "name": "Sine 5Hz",
  "y": [0, 0.841, 0.909, 0.141, ...],
  "x": [0, 0.1, 0.2, 0.3, ...],
  "y_unit": "V",
  "x_unit": "s",
  "target_source_id": "937896ff-f856-4b20-8888-e5127f0835b5"
}

Example: Trace Line (1D Z axis)

{
  "name": "Colored Sine",
  "y": [0, 0.841, 0.909, ...],
  "x": [0, 0.1, 0.2, ...],
  "z": [0.5, 0.7, 0.9, ...],
  "y_unit": "V",
  "x_unit": "s",
  "z_unit": "°C",
  "target_source_id": "937896ff-f856-4b20-8888-e5127f0835b5"
}

Example: Spectrogram (2D Z Matrix)

{
  "name": "Spectrogram",
  "y": [0, 10, 20, ...],
  "x": [0, 0.1, 0.2, ...],
  "z": [[0.1, 0.2, ...], [0.3, 0.4, ...], ...],
  "y_unit": "Hz",
  "x_unit": "s",
  "z_unit": "dB",
  "target_source_id": "937896ff-f856-4b20-8888-e5127f0835b5"
}

Info

Z axis format:

1D array (length = length of x and y): trace line with color coding
2D matrix (shape: [len(y), len(x)]): spectrogram/heatmap

Large data

This endpoint only accepts inline JSON (best for small signals). Transfer large arrays as a binary upload instead – a single signal via POST /api/signals/upload, many signals in one request via POST /api/signals/upload_batch. This avoids the JSON overhead and works inside the Flatpak sandbox too.

Response

Status Code: 200 OK

Body:

{
  "status": "ok",
  "result": {
    "signal_id": "7c9e6679-7425-40de-944b-e07fc1f90ae7",
    "name": "Sine 5Hz",
    "sample_count": 1000
  }
}

Response Fields

Field	Type	Description
`result.signal_id`	string	ID of the imported signal
`result.name`	string	Actual name of the signal
`result.sample_count`	integer	Number of imported samples

Errors

Status	Meaning
`400`	Invalid parameters (e.g. missing `y` array, or a `file` field – upload file contents via `/api/signals/upload` instead)
`404`	`target_source_id` not found
`500`	Server error

Example:

{
  "status": "error",
  "error": "No handler found for source ID: 937896ff-..."
}