Data Model

Overview

All data is organized in a three-level hierarchy:

Module
  └─ Property (one or many per module)
       └─ Element (one or many per property)

Connection and initial state

On connection, send a DU request (see Client → Server).
The server replies with a full dump message (d) containing all modules, controller data, and file lists.

Modules

A module represents a functional subsystem (focus, guiding, allsky camera, etc.).
Its identifier is its internal name (no spaces).

Field	Type	Description
`infos.label`	string	Human-readable module label
`infos.name`	string	Internal module name
`infos.description`	string	Module description
`infos.template`	string	Module template/type (e.g. `"focus"`, `"guider"`)
`properties`	object	Map of property name → property object
`globallovs`	object	Map of LOV key → LOV object (module-level lists of values)
`profile.name`	string	Currently active profile name
`profile.changed`	bool	Whether the profile has unsaved changes

Wire format

In the JSON wire format, properties is abbreviated as p, globallovs as l, and profile as f. Clients must handle these abbreviated keys.

Properties

A property groups related elements. Properties are displayed hierarchically using level1 and level2.

Field	Type	Description
`label`	string	Display label
`order`	string	Sort order within the same level
`level1`	string	First hierarchy level (e.g. tab name)
`level2`	string	Second hierarchy level (e.g. group name)
`status`	int	`0` Standby · `1` OK (green) · `2` Busy (yellow) · `3` Error (red)
`permission`	int	`0` Read-only · `1` Write-only · `2` Read-write
`enabled`	bool	Whether the property can be interacted with
`badge`	bool	Whether the property is in the favourites list
`preicon1`	string	Icon before the label (Google Fonts icon name)
`preicon2`	string	Second icon before the label
`posticon1`	string	Icon after the label
`posticon2`	string	Second icon after the label
`showElts`	bool	Whether element values should be shown inline
`hasprofile`	bool	Whether the property is saved in profiles
`freevalue`	string	Arbitrary free-text field
`rule`	int	Bool element grouping rule: `0` OneOfMany (radio) · `1` AtMostOne · `2` Any
`elements`	object	Map of element name → element object

Grid properties (when hasGrid: true):

Field	Type	Description
`hasGrid`	bool	Property has tabular grid data
`showGrid`	bool	Grid should be shown by default
`gridLimit`	int	Maximum number of grid rows
`gridheaders`	string[]	Column order (element names)
`grid`	array of arrays	Grid rows; each row is an array of values in `gridheaders` order

Graph properties (when hasGraph: true):

Field	Type	Description
`hasGraph`	bool	Property has a graph
`graphType`	string	`"XY"` · `"DY"` (time-axis) · `"PHD"` (guiding)
`graphParams`	object	Graph configuration

Wire format

In the JSON wire format, elements is abbreviated as e.

Elements

An element holds a single typed value. There are 11 element types.

Common fields (all elements, in full dump)

Field	Type	Description
`type`	string	Element type (see list below)
`label`	string	Display label
`order`	string	Sort order within the property
`hint`	string	Tooltip/help text
`autoupdate`	bool	Internal backend flag; not used by clients
`badge`	bool	Whether the element is in the favourites list
`directedit`	bool	`true` = send `SV` on change; `false` = batch with `SA`
`preicon`	string	Icon before the element (optional)
`posticon`	string	Icon after the element (optional)

Partial updates

In ee and ea update messages, elements contain only their value — no metadata fields. Clients must preserve metadata from the last full dump.

Type: `int`

Field	Type	Description
`value`	int	Current integer value
`min`	int	Minimum allowed value
`max`	int	Maximum allowed value
`step`	int	Increment step
`format`	string	Display format string
`slider`	int	`0` no slider · `1` slider only · `2` slider + value input
`listOfValues`	object	Optional: `{"key": "Label"}` map of allowed values
`globallov`	string	Optional: key referencing a module or controller LOV
`lovScope`	string	`"module"` or `"controller"` — where the globallov is defined
`lovConstrained`	bool	Whether value must belong to the LOV

Type: `float`

Same fields as int, with floating-point value, min, max, step.

Type: `bool`

Field	Type	Description
`value`	bool	`true` or `false`

Type: `string`

Field	Type	Description
`value`	string	Text value
`listOfValues`	object	Optional: `{"key": "Label"}` map of allowed values
`globallov`	string	Optional: key referencing a LOV
`lovScope`	string	`"module"` or `"controller"`

Type: `date`

Field	Type	Description
`value`	object	`{"year": int, "month": int (1-12), "day": int (1-31)}`

Type: `time`

Field	Type	Description
`value`	object	`{"hh": int, "mm": int, "ss": int, "ms": int}`
`usems`	bool	Whether milliseconds should be displayed

Type: `datetime`

Field	Type	Description
`value`	object	`{"year": int, "month": int, "day": int, "hh": int, "mm": int, "ss": int, "ms": int}`

Type: `img`

The value field is an object with image metadata:

Field	Type	Description
`urljpeg`	string	Relative path to JPEG image (use with `/ostmedia/` base URL)
`urlfits`	string	Relative path to FITS file
`urlthumbnail`	string	Relative path to thumbnail
`urloverlay`	string	Relative path to overlay image
`channels`	int	Number of colour channels
`width` / `height`	int	Image dimensions in pixels
`snr`	float	Signal-to-noise ratio
`hfravg`	float	Average HFR (half-flux radius) of detected stars
`stars`	int	Number of detected stars
`issolved`	bool	Whether plate solving succeeded
`solverra` / `solverde`	float	Solved RA/Dec coordinates
`solverorientation`	float	Solved field rotation angle
`min` / `max` / `mean` / `median` / `stddev`	float[]	Per-channel statistics
`histogram`	array	Per-channel histogram data
`alternates`	string[]	Optional: alternative versions of the image

Media URLs

All image/video paths are relative. Prepend http(s)://hostname/ostmedia/ to get the full URL.
Example: "urljpeg": "Focus/frame.jpeg" → http://hostname/ostmedia/Focus/frame.jpeg

Type: `video`

Field	Type	Description
`value`	object	`{"url": "relative/path/to/video.mp4"}`

In partial update (ea) messages, the video element may contain url directly at the element level rather than nested in value.

Type: `light`

Field	Type	Description
`value`	int	`0` Standby · `1` OK · `2` Warning · `3` Error

Type: `prg`

Field	Type	Description
`value`	object	`{"value": float (0–100), "dynlabel": string}`
`prgtype`	string	`"bar"` or `"spinner"`

Type: `message` (not yet implemented in current backend)

Reserved for log/message display.

Lists of Values (LOV)

LOVs provide a set of allowed values for int, float, and string elements.

Local LOV — embedded in the element:

"listOfValues": {
  "1": "Option One",
  "2": "Option Two"
}

Global LOV — referenced by key:

"globallov": "myCameraModels",
"lovScope": "module"

The LOV itself is defined at module level (globallovs) or controller level (controllerlovs):

"myCameraModels": {
  "label": "Camera models",
  "type": "string",
  "values": {
    "ASI294MC": "ZWO ASI 294 MC",
    "ASI533MC": "ZWO ASI 533 MC"
  }
}

Built-in controller LOVs (always available):

Key	Contents
`loadedModules`	All loaded modules: `{moduleName: label}`
`loadedModules-<template>`	Modules filtered by template (e.g. `loadedModules-focus`)
`profiles-<template>`	Available profiles for a module type

Access control

The dump response includes grant-server and grant-client values:

Value	Meaning
`"1"`	Full read-write access
`"0"`	Read-only
`"-1"`	Access denied (login required)

If grant-client is "-1", no module data is sent. Use the LO (login) message to authenticate.

Data Model

Overview

Connection and initial state

Modules

Properties

Elements

Common fields (all elements, in full dump)

Type: int

Type: float

Type: bool

Type: string

Type: date

Type: time

Type: datetime

Type: img

Type: video

Type: light

Type: prg

Type: message (not yet implemented in current backend)