highascg

CG API — HTML templates (CG AMCP)

CasparCG HTML/template CG commands on a channel layer. Templates live under the Caspar template path; data payloads are XML/JSON strings passed on add/update.

Caspar: required (503 if AMCP is down).

Implementation: src/api/routes-cg.js · AMCP: src/caspar/amcp-cg.js

AMCP table: docs/reference/amcp-mapping.md

Mixer and scene APIs: mixer.md, scene-take.md.

Endpoint pattern

POST /api/cg/{command}
Content-Type: application/json
{command} AMCP Description
add CG ADD Register template on layer
remove CG REMOVE Remove template instance
clear CG CLEAR Clear all CG on layer
play CG PLAY Play template
stop CG STOP Stop template
next CG NEXT Next step/page
goto CG GOTO Jump to label
update CG UPDATE Push new template data
invoke CG INVOKE Call template method
info CG INFO Query template state

Unknown command → 400 { "error": "Unknown CG command: …" }.

Common request fields

Field Type Default Description
channel number 1 Caspar channel
layer number — Caspar layer hosting CG (channel-layer)
templateHostLayer number 1 CG sub-layer index on that layer (Caspar “template layer”)
template string — Template name (for add)
playOnLoad boolean false 1 / 0 on CG ADD
data string — Template data XML/JSON (add/update)
label string — Goto label (goto)
method string — Method name (invoke)

AMCP shape: CG {channel}-{layer} {SUBCMD} {templateHostLayer} …

Example: channel 1, layer 10, template host 1 → CG 1-10 ADD 1 "my_template" 1 <data…>.

Commands

POST /api/cg/add

Load a template onto the layer.

{
  "channel": 1,
  "layer": 10,
  "templateHostLayer": 1,
  "template": "lower_third",
  "playOnLoad": true,
  "data": "<template><text id=\"title\">Hello</text></template>"
}

When data is non-empty, the server sends raw AMCP (escaping handled in amcp-cg.js). Empty data uses typed cgAdd.

POST /api/cg/update

Replace template data without re-adding:

{
  "channel": 1,
  "layer": 10,
  "templateHostLayer": 1,
  "data": "<template><text id=\"title\">Updated</text></template>"
}

POST /api/cg/play · stop · next

{ "channel": 1, "layer": 10, "templateHostLayer": 1 }

POST /api/cg/goto

{
  "channel": 1,
  "layer": 10,
  "templateHostLayer": 1,
  "label": "slide2"
}

POST /api/cg/invoke

{
  "channel": 1,
  "layer": 10,
  "templateHostLayer": 1,
  "method": "refresh"
}

POST /api/cg/remove

{ "channel": 1, "layer": 10, "templateHostLayer": 1 }

POST /api/cg/clear

Clears all CG templates on the layer (no templateHostLayer in AMCP):

{ "channel": 1, "layer": 10 }

POST /api/cg/info

{ "channel": 1, "layer": 10, "templateHostLayer": 1 }

Omit templateHostLayer to query layer-level CG info.

Examples

# Add lower third and auto-play
curl -s -X POST http://127.0.0.1:4200/api/cg/add \
  -H 'Content-Type: application/json' \
  -d '{
    "channel": 1,
    "layer": 998,
    "templateHostLayer": 1,
    "template": "lt",
    "playOnLoad": true,
    "data": "<template><text>ON AIR</text></template>"
  }'

# Update text
curl -s -X POST http://127.0.0.1:4200/api/cg/update \
  -H 'Content-Type: application/json' \
  -d '{
    "channel": 1,
    "layer": 998,
    "templateHostLayer": 1,
    "data": "<template><text>OFF AIR</text></template>"
  }'

# Remove
curl -s -X POST http://127.0.0.1:4200/api/cg/remove \
  -H 'Content-Type: application/json' \
  -d '{"channel":1,"layer":998,"templateHostLayer":1}'

await fetch(`${apiBase}/api/cg/add`, {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    channel: 1,
    layer: 10,
    template: 'clock',
    playOnLoad: true,
    data: '<template></template>',
  }),
})

Responses

200 — Passthrough Caspar JSON (ok, data, …).

502 — AMCP/command failure.

503 — Caspar not connected.

Templates list

Discover template names via GET /api/templates (requires Caspar) or GET /api/state → templates array.

Doc Topic
state-and-media.md /api/state, media index
mixer.md Layer opacity/fill (often combined with CG overlays)
scene-take.md Look layers may use source.type: "cg"

OpenAPI

openapi.yaml — CgCommand, CgAddRequest, shared CgLayerRequest.

This site is open source. Improve this page.