Validate

Compiles a dxScript source file, executes it on a synthetic candle snapshot, and returns declared metadata or a structured error.

Service: dxscript.indicators.v1.IndicatorService
Method: validate
Interaction: request / response

HTTP

POST /dxscript.indicators.v1.indicatorservice/validate
Content-Type: application/json

Request

Field	Type	Required	Description
lang	string	yes	Must be dxscript-js
content	string	yes	Full script source

Examples

Indicator validation (success)

curl -sS -X POST 'https://dxlink-dxscript-http-demo.dxkube.com/dxscript.indicators.v1.indicatorservice/validate' \
  -H 'Content-Type: application/json' \
  -d '{
    "lang": "dxscript-js",
    "content": "const n = input.double(\"length\", 14);\nfunction onTick() {\n  output(\"rsi\", ta.rsi(close, n));\n  spline(ta.rsi(close, n), {title: \"RSI\"});\n}"
  }'

Request body:

{
  "lang": "dxscript-js",
  "content": "const n = input.double(\"length\", 14);\nfunction onTick() {\n  output(\"rsi\", ta.rsi(close, n));\n  spline(ta.rsi(close, n), {title: \"RSI\"});\n}"
}

Response 200 — error is absent:

{
  "inParameters": [
    {
      "name": "length",
      "type": "INPUT_TYPE_DOUBLE",
      "doubleParam": {
        "defaultValue": 14.0
      }
    }
  ],
  "outputs": [
    { "name": "rsi" }
  ],
  "splines": [
    {
      "id": 0,
      "title": "RSI",
      "style": "LINE",
      "offset": 0,
      "overlay": true
    }
  ],
  "compilationTime": "0.006493433s",
  "executionTime": "0.018204370s",
  "executionTotalTicks": 1000,
  "calculationResult": {
    "output": {
      "rsi": {
        "values": ["NaN"]
      }
    },
    "spline": {
      "0": {
        "value": "NaN",
        "style": "LINE",
        "offset": 0,
        "title": "RSI",
        "overlay": true
      }
    }
  }
}

Empty layer lists (backgroundColors, barColors, shapes) are omitted. Timing and executionTotalTicks depend on server configuration (snapshotSize was 1000 on this stand).

First-bar samples reflect the synthetic snapshot only. Each output channel is { "values": [value] } with at most one entry. RSI returns "NaN" on the first bar when the lookback is not satisfied yet — that is still a successful validation. Non-finite doubles serialize as JSON strings ("NaN", "Infinity", "-Infinity"), not null.

Validation error (runtime)

curl -sS -X POST 'https://dxlink-dxscript-http-demo.dxkube.com/dxscript.indicators.v1.indicatorservice/validate' \
  -H 'Content-Type: application/json' \
  -d '{
    "lang": "dxscript-js",
    "content": "function onTick() {\n  spline(undefinedSeries, {title: \"Broken\"});\n}"
  }'

Response 200 — error is set; calculationResult and timing fields are absent:

{
  "error": {
    "id": "8104ca8b-e57c-405d-b6b8-37de865bf143",
    "type": "RUNTIME",
    "scriptName": "test_validate",
    "startLine": 2,
    "startColumn": 10,
    "endLine": 2,
    "endColumn": 24,
    "message": "undefinedSeries is not defined",
    "scriptStack": [
      { "functionName": "onTick", "line": 2, "column": 10 }
    ]
  }
}

Validation error (syntax)

curl -sS -X POST 'https://dxlink-dxscript-http-demo.dxkube.com/dxscript.indicators.v1.indicatorservice/validate' \
  -H 'Content-Type: application/json' \
  -d '{
    "lang": "dxscript-js",
    "content": "const x = ;"
  }'

Response 200:

{
  "error": {
    "id": "8a3caf2c-f629-4884-a60c-8821335bbd53",
    "type": "SYNTAX",
    "scriptName": "test_validate",
    "startLine": 1,
    "startColumn": 11,
    "endLine": 1,
    "endColumn": 11,
    "message": "Expected an operand but found ;"
  }
}

On failure, error is the only payload field. scriptStack is omitted when empty. scriptName is assigned by the server.

Response fields

Field	Type	Description
inParameters	array	Declared input() parameters with typed defaults
outputs	array	{ name } entries from output()
splines	array	Spline layer metadata (id, title, style, offset, overlay)
backgroundColors	array	bgColor() layer metadata; omitted when empty
barColors	array	barColor() layer metadata; omitted when empty
shapes	array	shape() layer metadata; omitted when empty
meta	object	title, shortTitle when declared by indicator() or strategy()
compilationTime	string	Duration (e.g. "0.240804875s"); present on success only
executionTime	string	Wall-clock script execution duration; present on success only
executionTotalTicks	int	Number of candles the script ran over; present on success only
calculationResult	object	First-bar samples (see below); present on success only
strategyAnalytics	object	Performance summary of a strategy() run (performance only); omitted for non-strategy scripts
error	object	Structured script error; present on failure only

inParameters types

Each parameter has name, type, and exactly one typed payload:

type	Payload field	Description
INPUT_TYPE_BOOL	boolParam	{ defaultValue }
INPUT_TYPE_DOUBLE	doubleParam	{ defaultValue, min?, max?, step?, options? }
INPUT_TYPE_STRING	stringParam	{ defaultValue, options? }
INPUT_TYPE_SOURCE	sourceParam	{ defaultValue, options? }
INPUT_TYPE_COLOR	colorParam	{ defaultValue, defaultAlpha? }
INPUT_TYPE_SESSION	sessionParam	{ defaultValue, options?, value, timeZone? }
INPUT_TYPE_ENUM	enumParam	{ defaultValue, options? }

calculationResult

First-bar samples only, one value per series or layer:

Channel	Map key	Value shape
output	output channel name	{ values: [value] } — first bar only (at most one entry); empty values when there is no sample. Numbers or non-finite strings ("NaN", "Infinity", "-Infinity")
spline	layer id ("0", "1", …)	Spline knot with value (number or "NaN" string), optional color, style, offset, title, overlay
backgroundColor	layer name	{ color, offset?, title?, numberOfLast?, overlay }
barColor	layer name	{ color, offset?, title?, numberOfLast? }
shape	series name	{ value, color?, textColor?, text?, shapeStyle?, offset?, title?, location?, overlay? }

Unset channels are omitted from calculationResult. Colors use { "value": "<hex or palette name>", "alpha"?: number }.

WebSocket RPC

Call validate on service dxscript.indicators.v1.IndicatorService through the dxLink WebSocket session using the same ValidateRequest / ValidateResponse protobuf messages. JSON field names match the HTTP mapping.

Strategy scripts

Strategy support can be disabled on a deployment. In that case, scripts that call strategy() fail validation at compile time.

For a strategy script the response also carries the run's performance summary in strategyAnalytics.performance, in the shape the backtest response uses. It is present for every strategy run, including one that traded nothing. The rest of what a backtest returns — equitySeries, barCloseSeries, fills, trades and orders — is left out, as calculationResult is cut to first-bar samples: one value per bar would make up most of the response and describe nothing real.

The candles are generated, not market data. The summary shows that the strategy compiled and ran; its numbers describe the synthetic series and say nothing about any instrument. Use Backtest for a run over real candles.

See also

• Validator service
• Indicator — indicator() declaration
• Strategy — strategy() declaration