> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/alchemy-run/alchemy/llms.txt
> Use this file to discover all available pages before exploring further.

# Worker

> API reference for Cloudflare Worker resource

# Worker

A Cloudflare Worker is a serverless function that runs on Cloudflare's global network.

## Props

<ParamField path="entrypoint" type="string">
  The entrypoint for the worker script.

  ```ts theme={null}
  const worker = await Worker("api", {
    entrypoint: "./src/worker.ts"
  });
  ```
</ParamField>

<ParamField path="script" type="string">
  Inline worker script (alternative to `entrypoint`).

  ```ts theme={null}
  const worker = await Worker("api", {
    script: "export default { fetch() { return new Response('Hello'); } }"
  });
  ```
</ParamField>

<ParamField path="name" type="string">
  Name for the worker.

  <Expandable title="default" defaultOpen>
    `${app}-${stage}-${id}`
  </Expandable>
</ParamField>

<ParamField path="bindings" type="Bindings">
  Bindings to attach to the worker.

  ```ts theme={null}
  const worker = await Worker("api", {
    entrypoint: "./src/worker.ts",
    bindings: {
      BUCKET: bucket,
      KV: kvNamespace,
      DB: database
    }
  });
  ```
</ParamField>

<ParamField path="url" type="boolean" default="false">
  Whether to enable a workers.dev URL for this worker.

  If true, the worker will be available at `{name}.{subdomain}.workers.dev`
</ParamField>

<ParamField path="routes" type="(string | RouteConfig)[]">
  Routes to create for this worker.

  ```ts theme={null}
  const worker = await Worker("api", {
    entrypoint: "./src/worker.ts",
    routes: [
      "api.example.com/*",
      { pattern: "sub.example.com/*", zoneId: "1234567890" }
    ]
  });
  ```
</ParamField>

<ParamField path="domains" type="(string | DomainConfig)[]">
  Custom domains to bind to the worker.

  ```ts theme={null}
  const worker = await Worker("api", {
    entrypoint: "./src/worker.ts",
    domains: [
      "api.example.com",
      { domainName: "example.com", zoneId: "1234567890" }
    ]
  });
  ```
</ParamField>

<ParamField path="compatibilityDate" type="string">
  The compatibility date for the worker.

  <Expandable title="default" defaultOpen>
    Automatically pinned to the latest Workers release
  </Expandable>
</ParamField>

<ParamField path="compatibilityFlags" type="string[]">
  The compatibility flags for the worker.
</ParamField>

<ParamField path="compatibility" type="CompatibilityPreset">
  Compatibility preset to automatically include common compatibility flags.

  * `"node"`: Includes nodejs\_compat flag for Node.js compatibility
</ParamField>

<ParamField path="crons" type="string[]">
  Cron expressions for the trigger. Uses standard cron syntax.

  ```ts theme={null}
  const worker = await Worker("scheduled", {
    entrypoint: "./src/scheduled.ts",
    crons: ['0 0 * * *', '0 12 * * MON']
  });
  ```
</ParamField>

<ParamField path="eventSources" type="EventSource[]">
  Event sources that this worker will consume.

  ```ts theme={null}
  const worker = await Worker("processor", {
    entrypoint: "./src/processor.ts",
    bindings: { QUEUE: queue },
    eventSources: [{
      queue,
      settings: {
        batchSize: 15,
        maxConcurrency: 3,
        maxRetries: 5
      }
    }]
  });
  ```
</ParamField>

<ParamField path="assets" type="AssetsConfig">
  Configuration for static assets.

  <Expandable title="properties">
    <ParamField path="_headers" type="string">
      Contents of a \_headers file (used to attach custom headers on asset responses).
    </ParamField>

    <ParamField path="_redirects" type="string">
      Contents of a \_redirects file (used to apply redirects or proxy paths).
    </ParamField>

    <ParamField path="html_handling" type="string" default="auto-trailing-slash">
      Determines the redirects and rewrites of requests for HTML content.

      Options: `"auto-trailing-slash"` | `"force-trailing-slash"` | `"drop-trailing-slash"` | `"none"`
    </ParamField>

    <ParamField path="not_found_handling" type="string" default="none">
      Determines the response when a request does not match a static asset.

      Options: `"none"` | `"404-page"` | `"single-page-application"`
    </ParamField>

    <ParamField path="run_worker_first" type="boolean | string[]" default="false">
      When true, requests will always invoke the Worker script.
      If an array is passed, the worker will be invoked for matching requests.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField path="placement" type="WorkerPlacement">
  Placement configuration for the worker.

  <Expandable title="properties">
    <ParamField path="mode" type="smart">
      Enable smart placement mode. Cloudflare automatically places your Worker closest to the upstream with the most requests.

      ```ts theme={null}
      const worker = await Worker("api", {
        entrypoint: "./src/worker.ts",
        placement: { mode: "smart" }
      });
      ```
    </ParamField>

    <ParamField path="region" type="string">
      Cloud provider region to place your Worker closest to.

      Format: `{provider}:{region}`

      ```ts theme={null}
      const worker = await Worker("api", {
        entrypoint: "./src/worker.ts",
        placement: { region: "aws:us-east-1" }
      });
      ```
    </ParamField>

    <ParamField path="host" type="string">
      Host endpoint to probe (TCP/layer 4) for placement.

      Format: `hostname:port`

      ```ts theme={null}
      const worker = await Worker("api", {
        entrypoint: "./src/worker.ts",
        placement: { host: "my-database.example.com:5432" }
      });
      ```
    </ParamField>

    <ParamField path="hostname" type="string">
      Hostname to probe (HTTP/layer 7) for placement.

      ```ts theme={null}
      const worker = await Worker("api", {
        entrypoint: "./src/worker.ts",
        placement: { hostname: "my-api.example.com" }
      });
      ```
    </ParamField>
  </Expandable>
</ParamField>

<ParamField path="limits" type="object">
  Resource limits for the worker.

  <Expandable title="properties">
    <ParamField path="cpu_ms" type="number" default="30000">
      The maximum CPU time in milliseconds that the worker can use.
    </ParamField>

    <ParamField path="subrequests" type="number">
      The maximum number of subrequests allowed per invocation.
      Defaults to 50 for free accounts and 10,000 for paid accounts.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField path="observability" type="WorkerObservability">
  Specify the observability behavior of the Worker.

  <Expandable title="properties">
    <ParamField path="enabled" type="boolean" default="true">
      If observability is enabled for this Worker.
    </ParamField>

    <ParamField path="headSamplingRate" type="number" default="1">
      A number between 0 and 1, where 0 indicates zero requests are logged, and 1 indicates every request is logged.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField path="logpush" type="boolean" default="false">
  Enable Workers Logpush to export trace events to external destinations.

  Requires a separate Logpush job configuration via the Cloudflare API.
</ParamField>

<ParamField path="version" type="string">
  Version label for this worker deployment.

  When specified, the worker will be published as a version with this label instead of updating the live deployment.

  ```ts theme={null}
  const worker = await Worker("my-worker", {
    entrypoint: "./src/worker.ts",
    version: "pr-123"
  });
  ```
</ParamField>

## Output

<ResponseField name="id" type="string">
  The ID of the worker.
</ResponseField>

<ResponseField name="name" type="string">
  The name of the worker.
</ResponseField>

<ResponseField name="url" type="string">
  The worker's URL if enabled. Format: `{name}.{subdomain}.workers.dev`
</ResponseField>

<ResponseField name="bindings" type="Bindings">
  The bindings that were created.
</ResponseField>

<ResponseField name="routes" type="Route[]">
  The routes that were created for this worker.
</ResponseField>

<ResponseField name="domains" type="CustomDomain[]">
  The custom domains that were created for this worker.
</ResponseField>

<ResponseField name="compatibilityDate" type="string">
  The compatibility date for the worker.
</ResponseField>

<ResponseField name="compatibilityFlags" type="string[]">
  The compatibility flags for the worker.
</ResponseField>

## Examples

### Basic HTTP Handler

```ts theme={null}
const api = await Worker("api", {
  name: "api-worker",
  entrypoint: "./src/api.ts",
  url: true
});
```

### Worker with Bindings

```ts theme={null}
const bucket = await R2Bucket("storage");
const kv = await KVNamespace("cache");
const db = await D1Database("db");

const worker = await Worker("api", {
  entrypoint: "./src/worker.ts",
  bindings: {
    BUCKET: bucket,
    CACHE: kv,
    DB: db
  }
});
```

### Worker with Custom Domain

```ts theme={null}
const worker = await Worker("api", {
  entrypoint: "./src/api.ts",
  domains: ["api.example.com"]
});
```

### Scheduled Worker

```ts theme={null}
const worker = await Worker("scheduled-tasks", {
  entrypoint: "./src/scheduled.ts",
  crons: ['* 15 * * *', '0 0 * * *', '0 12 * * MON']
});
```

### Queue Consumer

```ts theme={null}
const queue = await Queue("tasks");

const worker = await Worker("processor", {
  entrypoint: "./src/processor.ts",
  bindings: { QUEUE: queue },
  eventSources: [{
    queue,
    settings: {
      batchSize: 15,
      maxConcurrency: 3,
      maxRetries: 5,
      maxWaitTimeMs: 2500,
      retryDelay: 60
    }
  }]
});
```