This reference documents the type system used in Workflow Builder’s Domain Specific Language (DSL).
Expressions
Expressions evaluate to a value using a specified expression engine. Currently, JSONata is the supported expression type.
ExpressionType
export enum ExpressionType {
JSONATA = 'jsonata',
}
TExpr
export type TExpr = {
type: ExpressionType.JSONATA;
src: string
};
Evaluation scope
All expressions are evaluated against an environment containing:
| Variable | Description | Example |
|---|
__context__ | Global workflow context | __context__.customerId |
__steps__ | Step outputs by ID | __steps__.stepId.name |
__datasources__ | Datasource outputs by alias | __datasources__.dsId.data |
__each__ | Current item in iterations | __each__.id |
Value providers
TFieldRef
Defines how to access a field from different sources.
export enum FieldRefSource {
CONTEXT = 'CONTEXT',
STEP = 'STEP',
DATASOURCE = 'DATASOURCE',
EACH = 'EACH',
}
export type TFieldRef =
| { source: FieldRefSource.CONTEXT; path: string }
| { source: FieldRefSource.STEP; stepId: string; path: string }
| { source: FieldRefSource.DATASOURCE; key: string; path: string }
| { source: FieldRefSource.EACH; path: string };
| Source | Description |
|---|
CONTEXT | Access from global context |
STEP | Access from step output |
DATASOURCE | Access from datasource output |
EACH | Access current item in loops |
The path property uses dot notation (e.g., "director.id") powered by the dot-props library.
TValueProvider
Defines how to produce a value:
export type TValueProvider =
| { type: "const"; value: unknown }
| { type: "field"; ref: TFieldRef }
| { type: "expr"; expr: TExpr };
| Type | Description |
|---|
const | Hardcoded value |
field | Value from a field reference |
expr | Computed expression result |
TParamValue
Used for datasource or function parameters:
export type TParamValue =
| TValueProvider
| { [k: string]: TParamValue }
| TParamValue[];
Datasource calls
TDataSourceCall
export enum DataSourceType {
COMMENDA_LOGICAL_BACKEND = 'COMMENDA_LOGICAL_BACKEND',
}
export type TDataSourceCall = {
id: string;
alias: string;
type: DataSourceType.COMMENDA_LOGICAL_BACKEND;
dataSourceID: string;
params?: TParamValue;
select?: TExpr;
scope?: 'per-step' | 'per-item';
};
| Property | Description |
|---|
id | Unique identifier |
alias | Reference name for accessing results |
type | Datasource type |
dataSourceID | Database reference to datasource definition |
params | Parameters to pass to the datasource |
select | Expression to transform output (default: entire output) |
scope | per-step (default) or per-item for batch workflows |
Iterator providers
TIterableProvider
Provides an array for iteration:
export enum IterableType {
EXPRESSION = 'EXPRESSION',
STEP = 'STEP',
DATASOURCE = 'DATASOURCE',
}
export type TIterableProvider =
| { type: IterableType.EXPRESSION; expr: TExpr }
| { type: IterableType.STEP; stepId: string; select?: TExpr }
| { type: IterableType.DATASOURCE; key: string; select?: TExpr };
| Type | Description |
|---|
EXPRESSION | Evaluate expression against context |
STEP | Access step output array |
DATASOURCE | Access datasource output array |
Mappings
TMapping
Specifies how to write values to a target:
export type TMapping = {
id: string;
targetPath: string;
value: TValueProvider;
mode?: 'set' | 'append';
};
| Property | Description |
|---|
id | Unique identifier |
targetPath | Dot-notation destination path |
value | How to derive the value |
mode | set (replace, default) or append (for arrays) |
Example
{
"id": "map-directorId",
"targetPath": "directorId",
"value": {
"type": "expr",
"expr": { "src": "__each__.id" }
},
"mode": "set"
}
directorId to the current batch item’s id.
Step types enum
export enum WorkflowStepType {
START = 'start',
END = 'end',
HUMAN_URL_REDIRECT = 'human.url_redirect',
HUMAN_FORM = 'human.form',
HUMAN_CONFIRM = 'human.confirm',
HUMAN_DOC_UPLOAD = 'human.doc_upload',
SYS_SUB_WORKFLOW = 'sys.sub_workflow',
GATEWAY_PARALLEL_SPLIT = 'gateway.parallel_split',
GATEWAY_PARALLEL_JOIN = 'gateway.parallel_join',
GATEWAY_EXCLUSIVE_SPLIT = 'gateway.exclusive_split',
GATEWAY_INCLUSIVE_SPLIT = 'gateway.inclusive_split',
}
Sub-workflow modes
export enum SubWorkflowStepMode {
SINGLE = 'SINGLE',
BATCH = 'BATCH',
}
| Mode | Description |
|---|
SINGLE | Execute one child workflow |
BATCH | Execute child workflow for each item in collection |
Next steps
Definition types
Workflow definition structure
Runtime types
Execution runtime types
