write-script-deno

CLI Commands

Place scripts in a folder. After writing, tell the user they can run:

• wmill script generate-metadata - Generate .script.yaml and .lock files
• wmill sync push - Deploy to Windmill

Do NOT run these commands yourself. Instead, inform the user that they should run them.

Use wmill resource-type list --schema to discover available resource types.

TypeScript (Deno)

Deno runtime with npm support via npm: prefix and native Deno libraries.

Structure

Export a single async function called main:

export async function main(param1: string, param2: number) {
  // Your code here
  return { result: param1, count: param2 };
}

Do not call the main function. Libraries are installed automatically.

Resource Types

On Windmill, credentials and configuration are stored in resources and passed as parameters to main.

Use the RT namespace for resource types:

export async function main(stripe: RT.Stripe) {
  // stripe contains API key and config from the resource
}

Only use resource types if you need them to satisfy the instructions. Always use the RT namespace.

Before using a resource type, check the rt.d.ts file in the project root to see all available resource types and their fields. This file is generated by wmill resource-type generate-namespace.

Imports

// npm packages use npm: prefix
import Stripe from "npm:stripe";
import { someFunction } from "npm:some-package";

// Deno standard library
import { serve } from "https://deno.land/std/http/server.ts";

Windmill Client

Import the windmill client for platform interactions:

import * as wmill from "windmill-client";

See the SDK documentation for available methods.

Preprocessor Scripts

For preprocessor scripts, the function should be named preprocessor and receives an event parameter:

type Event = {
  kind:
    | "webhook"
    | "http"
    | "websocket"
    | "kafka"
    | "email"
    | "nats"
    | "postgres"
    | "sqs"
    | "mqtt"
    | "gcp";
  body: any;
  headers: Record<string, string>;
  query: Record<string, string>;
};

export async function preprocessor(event: Event) {
  return {
    param1: event.body.field1,
    param2: event.query.id,
  };
}

S3 Object Operations

Windmill provides built-in support for S3-compatible storage operations.

S3Object Type

The S3Object type represents a file in S3 storage:

type S3Object = {
  s3: string; // Path within the bucket
};

TypeScript Operations

import * as wmill from "windmill-client";

// Load file content from S3
const content: Uint8Array = await wmill.loadS3File(s3object);

// Load file as stream
const blob: Blob = await wmill.loadS3FileStream(s3object);

// Write file to S3
const result: S3Object = await wmill.writeS3File(
  s3object, // Target path (or undefined to auto-generate)
  fileContent, // string or Blob
  s3ResourcePath // Optional: specific S3 resource to use
);

TypeScript SDK (windmill-client)

Import: import * as wmill from 'windmill-client'

/**

• Initialize the Windmill client with authentication token and base URL
• @param token - Authentication token (defaults to WM_TOKEN env variable)
• @param baseUrl - API base URL (defaults to BASE_INTERNAL_URL or BASE_URL env variable) */ setClient(token?: string, baseUrl?: string): void

/**

• Create a client configuration from env variables
• @returns client configuration */ getWorkspace(): string

/**

• Get a resource value by path
• @param path path of the resource, default to internal state path
• @param undefinedIfEmpty if the resource does not exist, return undefined instead of throwing an error
• @returns resource value */ async getResource(path?: string, undefinedIfEmpty?: boolean): Promise<any>

/**

• Get the true root job id
• @param jobId job id to get the root job id from (default to current job)
• @returns root job id */ async getRootJobId(jobId?: string): Promise<string>

/**

• @deprecated Use runScriptByPath or runScriptByHash instead */ async runScript(path: string | null = null, hash_: string | null = null, args: Record<string, any> | null = null, verbose: boolean = false): Promise<any>

/**

• Run a script synchronously by its path and wait for the result
• @param path - Script path in Windmill
• @param args - Arguments to pass to the script
• @param verbose - Enable verbose logging
• @returns Script execution result */ async runScriptByPath(path: string, args: Record<string, any> | null = null, verbose: boolean = false): Promise<any>

/**

• Run a script synchronously by its hash and wait for the result
• @param hash_ - Script hash in Windmill
• @param args - Arguments to pass to the script
• @param verbose - Enable verbose logging
• @returns Script execution result */ async runScriptByHash(hash_: string, args: Record<string, any> | null = null, verbose: boolean = false): Promise<any>

/**

• Append a text to the result stream
• @param text text to append to the result stream */ appendToResultStream(text: string): void

/**

• Stream to the result stream
• @param stream stream to stream to the result stream */ async streamResult(stream: AsyncIterable<string>): Promise<void>

/**

• Run a flow synchronously by its path and wait for the result
• @param path - Flow path in Windmill
• @param args - Arguments to pass to the flow
• @param verbose - Enable verbose logging
• @returns Flow execution result */ async runFlow(path: string | null = null, args: Record<string, any> | null = null, verbose: boolean = false): Promise<any>

/**

• Wait for a job to complete and return its result
• @param jobId - ID of the job to wait for
• @param verbose - Enable verbose logging
• @returns Job result when completed */ async waitJob(jobId: string, verbose: boolean = false): Promise<any>

/**

• Get the result of a completed job
• @param jobId - ID of the completed job
• @returns Job result */ async getResult(jobId: string): Promise<any>

/**

• Get the result of a job if completed, or its current status
• @param jobId - ID of the job
• @returns Object with started, completed, success, and result properties */ async getResultMaybe(jobId: string): Promise<any>

/**

• @deprecated Use runScriptByPathAsync or runScriptByHashAsync instead */ async runScriptAsync(path: string | null, hash_: string | null, args: Record<string, any> | null, scheduledInSeconds: number | null = null): Promise<string>

/**

• Run a script asynchronously by its path
• @param path - Script path in Windmill
• @param args - Arguments to pass to the script
• @param scheduledInSeconds - Schedule execution for a future time (in seconds)
• @returns Job ID of the created job */ async runScriptByPathAsync(path: string, args: Record<string, any> | null = null, scheduledInSeconds: number | null = null): Promise<string>

/**

• Run a script asynchronously by its hash
• @param hash_ - Script hash in Windmill
• @param args - Arguments to pass to the script
• @param scheduledInSeconds - Schedule execution for a future time (in seconds)
• @returns Job ID of the created job */ async runScriptByHashAsync(hash_: string, args: Record<string, any> | null = null, scheduledInSeconds: number | null = null): Promise<string>

/**

• Run a flow asynchronously by its path
• @param path - Flow path in Windmill
• @param args - Arguments to pass to the flow
• @param scheduledInSeconds - Schedule execution for a future time (in seconds)
• @param doNotTrackInParent - If false, tracks state in parent job (only use when fully awaiting the job)
• @returns Job ID of the created job */ async runFlowAsync(path: string | null, args: Record<string, any> | null, scheduledInSeconds: number | null = null, // can only be set to false if this the job will be fully await and not concurrent with any other job // as otherwise the child flow and its own child will store their state in the parent job which will // lead to incorrectness and failures doNotTrackInParent: boolean = true): Promise<string>

/**

• Resolve a resource value in case the default value was picked because the input payload was undefined
• @param obj resource value or path of the resource under the format $res:path
• @returns resource value */ async resolveDefaultResource(obj: any): Promise<any>

/**

• Get the state file path from environment variables
• @returns State path string */ getStatePath(): string

/**

• Set a resource value by path
• @param path path of the resource to set, default to state path
• @param value new value of the resource to set
• @param initializeToTypeIfNotExist if the resource does not exist, initialize it with this type */ async setResource(value: any, path?: string, initializeToTypeIfNotExist?: string): Promise<void>

/**

• Set the state
• @param state state to set
• @deprecated use setState instead */ async setInternalState(state: any): Promise<void>

/**

• Set the state
• @param state state to set
• @param path Optional state resource path override. Defaults to getStatePath(). */ async setState(state: any, path?: string): Promise<void>

/**

• Set the progress
• Progress cannot go back and limited to 0% to 99% range
• @param percent Progress to set in %
• @param jobId? Job to set progress for */ async setProgress(percent: number, jobId?: any): Promise<void>

/**

• Get the progress
• @param jobId? Job to get progress from
• @returns Optional clamped between 0 and 100 progress value */ async getProgress(jobId?: any): Promise<number | null>

/**

• Set a flow user state
• @param key key of the state
• @param value value of the state */ async setFlowUserState(key: string, value: any, errorIfNotPossible?: boolean): Promise<void>

/**

• Get a flow user state
• @param path path of the variable */ async getFlowUserState(key: string, errorIfNotPossible?: boolean): Promise<any>

/**

• Get the internal state
• @deprecated use getState instea

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