Workflow DSL

The Vertesia Platform uses a DSL to define workflows. The DSL is a JSON object that describes the steps of the workflow. Each step can be either an activity or a child workflow.

Activities

The following activities are available:

Activity Name	Description	Parameters	Output
extractText	Extracts text from a document.	`document`: The document to extract text from.	`text`: The extracted text.
generateText	Generates text using a prompt template.	`prompt`: The prompt template to use. `data`: The data to pass to the prompt template.	`text`: The generated text.
translateText	Translates text from one language to another.	`text`: The text to translate. `targetLanguage`: The target language.	`translatedText`: The translated text.
summarizeText	Summarizes text.	`text`: The text to summarize.	`summary`: The summarized text.
analyzeSentiment	Analyzes the sentiment of text.	`text`: The text to analyze.	`sentiment`: The sentiment of the text.
classifyText	Classifies text into categories.	`text`: The text to classify. `categories`: The categories to classify into.	`category`: The category of the text.
extractEntities	Extracts entities from text.	`text`: The text to extract entities from.	`entities`: The extracted entities.
generateEmbeddings	Generates embeddings for text.	`text`: The text to generate embeddings for.	`embeddings`: The generated embeddings.
searchEmbeddings	Searches for similar text using embeddings.	`embeddings`: The embeddings to search for.	`results`: The search results.
createDocument	Creates a new document.	`type`: The type of the document. `properties`: The properties of the document.	`document`: The created document.
updateDocument	Updates an existing document.	`document`: The document to update. `properties`: The properties to update.	`document`: The updated document.
deleteDocument	Deletes an existing document.	`document`: The document to delete.
executeInteraction	Executes an existing interaction.	`interaction`: The interaction to execute. `data`: The data to pass to the interaction.	`result`: The result of the interaction.
runJavascriptCode	Runs JavaScript code.	`code`: The JavaScript code to run.	`result`: The result of the code execution.
sleep	Pauses the workflow for a specified amount of time.	`duration`: The duration to pause for.
log	Logs a message to the console.	`message`: The message to log.

Child Workflows

Child workflows are used to execute another workflow as a step in the current workflow. The name property specifies the endpoint of the child workflow to execute. The async property specifies whether or not to wait for the child workflow to finish before continuing the current workflow.

Example DSL Workflow

{
  "name": "My Workflow",
  "description": "This is my workflow.",
  "vars": {
    "myVariable": "Hello World!"
  },
  "steps": [
    {
      "type": "activity",
      "name": "log",
      "params": {
        "message": "The value of myVariable is: ${myVariable}"
      }
    },
    {
      "type": "workflow",
      "name": "My Child Workflow",
      "async": true,
      "output": "childWorkflowResult"
    }
  ]
}

DSL Variables

The DSL supports variables that can be used to store data and pass it between steps. Variables are defined in the vars property of the workflow. The value of a variable can be a literal value or a reference to another variable. References to variables are enclosed in ${}. For example, the following DSL defines a variable named myVariable with the value "Hello World!":

{
  "vars": {
    "myVariable": "Hello World!"
  }
}

The value of myVariable can then be referenced in other parts of the DSL using ${myVariable}. For example, the following DSL logs the value of myVariable to the console:

{
  "steps": [
    {
      "type": "activity",
      "name": "log",
      "params": {
        "message": "The value of myVariable is: ${myVariable}"
      }
    }
  ]
}

DSL Conditions

The DSL supports conditions that can be used to control the flow of the workflow. Conditions are defined in the condition property of a step. The value of a condition is a JSON object that describes the condition. The following operators are supported:

Operator	Description
`$eq`	Equal to
`$ne`	Not equal to
`$gt`	Greater than
`$gte`	Greater than or equal to
`$lt`	Less than
`$lte`	Less than or equal to
`$in`	In array
`$nin`	Not in array
`$regexp`	Matches regular expression

For example, the following DSL defines a step that only executes if the value of the variable myVariable is equal to "Hello World!":

{
  "steps": [
    {
      "type": "activity",
      "name": "log",
      "condition": {
        "$eq": {
          "myVariable": "Hello World!"
        }
      },
      "params": {
        "message": "The value of myVariable is: ${myVariable}"
      }
    }
  ]
}

DSL Fetch

The DSL supports fetching data from external sources during the workflow execution. The fetch property of a step is used to define the data to fetch. The value of the fetch property is a JSON object that describes the data to fetch. The following properties are supported:

Property	Description
`type`	The type of data to fetch.
`source`	The source of the data.
`query`	The query to use to fetch the data.
`select`	The fields to select from the fetched data.
`limit`	The maximum number of results to fetch.
`on_not_found`	How to handle not found objects.

For example, the following DSL defines a step that fetches a document from the store:

{
  "steps": [
    {
      "type": "activity",
      "name": "fetchDocument",
      "fetch": {
        "type": "document",
        "query": {
          "id": "${documentId}"
        }
      },
      "output": "document"
    }
  ]
}

DSL Projection

The DSL supports projecting data from the result of an activity. The projection property of a step is used to define the data to project. The value of the projection property is a JSON object that describes the data to project. The following operators are supported:

Operator	Description
`$include`	Include the specified fields.
`$exclude`	Exclude the specified fields.

For example, the following DSL defines a step that projects the name and description fields from the result of the fetchDocument activity:

{
  "steps": [
    {
      "type": "activity",
      "name": "fetchDocument",
      "fetch": {
        "type": "document",
        "query": {
          "id": "${documentId}"
        }
      },
      "output": "document"
    },
    {
      "type": "activity",
      "name": "projectDocument",
      "params": {
        "document": "${document}"
      },
      "projection": {
        "$include": [
          "name",
          "description"
        ]
      },
      "output": "projectedDocument"
    }
  ]
}