method

bun.S3Client.write

path: string,
data: string | ArrayBuffer | SharedArrayBuffer | Blob | BunFile | Request | Response | File | ArrayBufferView<ArrayBufferLike> | S3File | Archive,
options?: S3Options
): Promise<number>;

Writes data directly to a path in the bucket. Supports strings, buffers, streams, and web API types.

@param path

The path to the file in the bucket

@param data

The data to write to the file

@param options

Additional S3 options to override defaults

@returns

The number of bytes written

// Write string
await bucket.write("hello.txt", "Hello World");

// Write JSON with type
await bucket.write(
  "data.json",
  JSON.stringify({hello: "world"}),
  {type: "application/json"}
);

// Write from fetch
const res = await fetch("https://example.com/data");
await bucket.write("data.bin", res);

// Write with ACL
await bucket.write("public.html", html, {
  acl: "public-read",
  type: "text/html"
});

Referenced types

class ArrayBuffer

Represents a raw buffer of binary data, which is used to store data for the different typed arrays. ArrayBuffers cannot be read from or written to directly, but can be passed to a typed array or DataView Object to interpret the raw buffer as needed.

  • readonly [Symbol.toStringTag]: string
  • readonly byteLength: number

    Read-only. The length of the ArrayBuffer (in bytes).

  • newByteLength?: number
    ): void;

    Resizes the ArrayBuffer to the specified size (in bytes).

    MDN

    byteLength: number

    Resize an ArrayBuffer in-place.

  • begin: number,
    end?: number

    Returns a section of an ArrayBuffer.

  • newByteLength?: number

    Creates a new ArrayBuffer with the same byte content as this buffer, then detaches this buffer.

    MDN

  • newByteLength?: number

    Creates a new non-resizable ArrayBuffer with the same byte content as this buffer, then detaches this buffer.

    MDN

interface SharedArrayBuffer

class Blob

A file-like object of immutable, raw data. Blobs represent data that isn't necessarily in a JavaScript-native format. The File interface is based on Blob, inheriting blob functionality and expanding it to support files on the user's system.

MDN Reference

  • readonly size: number
  • readonly type: string

  • Returns a promise that resolves to the contents of the blob as an ArrayBuffer

  • bytes(): Promise<Uint8Array<ArrayBufferLike>>;

    Returns a promise that resolves to the contents of the blob as a Uint8Array (array of bytes). Equivalent to new Uint8Array(await blob.arrayBuffer())

  • formData(): Promise<FormData>;

    Read the data from the blob as a FormData object.

    This first decodes the data from UTF-8, then parses it as a multipart/form-data body or an application/x-www-form-urlencoded body.

    The blob's type property determines the format of the body.

    This is a non-standard addition to the Blob API, to make it conform more closely to the BodyMixin API.

  • options?: ConstructorOptions
    ): Image;

    Wrap this blob in a Bun.Image pipeline. Equivalent to new Bun.Image(this, options) — the constructor is synchronous (the underlying read happens lazily when an Image terminal is awaited), so this works on Bun.file(), Bun.s3(), fd-backed and in-memory blobs alike:

    await Bun.file("photo.jpg").image().resize(400).webp().write("thumb.webp");
  • json(): Promise<any>;

    Read the data from the blob as a JSON object.

    This first decodes the data from UTF-8, then parses it as JSON.

  • start?: number,
    end?: number,
    contentType?: string
    ): Blob;

    Returns a new Blob with the bytes from start up to but not including end. Negative indices count from the end.

    @param start

    byte offset to start at. Defaults to 0.

    @param end

    byte offset to stop at. Defaults to size.

    @param contentType

    the type of the new Blob.

  • Returns a readable stream of the blob's contents

  • text(): Promise<string>;

    Returns a promise that resolves to the contents of the blob as a string

class Request

This Fetch API interface represents a resource request.

MDN Reference

  • readonly body: null | ReadableStream<Uint8Array<ArrayBufferLike>>
  • readonly bodyUsed: boolean
  • readonly cache: RequestCache

    Returns the cache mode associated with request, which is a string indicating how the request will interact with the browser's cache when fetching.

    MDN Reference

  • readonly credentials: RequestCredentials

    Returns the credentials mode associated with request, which is a string indicating whether credentials will be sent with the request always, never, or only when sent to a same-origin URL.

    MDN Reference

  • readonly destination: RequestDestination

    Returns the kind of resource requested by request, e.g., "document" or "script".

    MDN Reference

  • readonly headers: Headers

    Returns a Headers object consisting of the headers associated with request. Note that headers added in the network layer by the user agent will not be accounted for in this object, e.g., the "Host" header.

    MDN Reference

  • readonly integrity: string

    Returns request's subresource integrity metadata, which is a cryptographic hash of the resource being fetched. Its value consists of multiple hashes separated by whitespace. [SRI]

    MDN Reference

  • readonly keepalive: boolean

    Returns a boolean indicating whether or not request can outlive the global in which it was created.

    MDN Reference

  • readonly method: string

    Returns request's HTTP method, which is "GET" by default.

    MDN Reference

  • readonly mode: RequestMode

    Returns the mode associated with request, which is a string indicating whether the request will use CORS, or will be restricted to same-origin URLs.

    MDN Reference

  • readonly redirect: RequestRedirect

    Returns the redirect mode associated with request, which is a string indicating how redirects for the request will be handled during fetching. A request will follow redirects by default.

    MDN Reference

  • readonly referrer: string

    Returns the referrer of request. Its value can be a same-origin URL if explicitly set in init, the empty string to indicate no referrer, and "about:client" when defaulting to the global's default. This is used during fetching to determine the value of the Referer header of the request being made.

    MDN Reference

  • readonly referrerPolicy: ReferrerPolicy

    Returns the referrer policy associated with request. This is used during fetching to compute the value of the request's referrer.

    MDN Reference

  • readonly signal: AbortSignal

    Returns the signal associated with request, which is an AbortSignal object indicating whether or not request has been aborted, and its abort event handler.

    MDN Reference

  • readonly url: string
  • blob(): Promise<Blob>;
  • bytes(): Promise<Uint8Array<ArrayBufferLike>>;
  • json(): Promise<any>;
  • text(): Promise<string>;

  • Returns a ReadableStream of the body decoded as UTF-8 text.

    Multi-byte characters split across chunk boundaries are joined correctly. Throws a TypeError if the body has already been consumed or is locked.

class Response

This Fetch API interface represents the response to a request.

MDN Reference

class File

Provides information about files and allows JavaScript in a web page to access their content.

MDN Reference

  • readonly lastModified: number
  • readonly name: string
  • readonly size: number
  • readonly type: string

  • Returns a promise that resolves to the contents of the blob as an ArrayBuffer

  • bytes(): Promise<Uint8Array<ArrayBufferLike>>;

    Returns a promise that resolves to the contents of the blob as a Uint8Array (array of bytes). Equivalent to new Uint8Array(await blob.arrayBuffer())

  • formData(): Promise<FormData>;

    Read the data from the blob as a FormData object.

    This first decodes the data from UTF-8, then parses it as a multipart/form-data body or an application/x-www-form-urlencoded body.

    The blob's type property determines the format of the body.

    This is a non-standard addition to the Blob API, to make it conform more closely to the BodyMixin API.

  • options?: ConstructorOptions
    ): Image;

    Wrap this blob in a Bun.Image pipeline. Equivalent to new Bun.Image(this, options) — the constructor is synchronous (the underlying read happens lazily when an Image terminal is awaited), so this works on Bun.file(), Bun.s3(), fd-backed and in-memory blobs alike:

    await Bun.file("photo.jpg").image().resize(400).webp().write("thumb.webp");
  • json(): Promise<any>;

    Read the data from the blob as a JSON object.

    This first decodes the data from UTF-8, then parses it as JSON.

  • start?: number,
    end?: number,
    contentType?: string
    ): Blob;

    Returns a new Blob with the bytes from start up to but not including end. Negative indices count from the end.

    @param start

    byte offset to start at. Defaults to 0.

    @param end

    byte offset to stop at. Defaults to size.

    @param contentType

    the type of the new Blob.

  • Returns a readable stream of the blob's contents

  • text(): Promise<string>;

    Returns a promise that resolves to the contents of the blob as a string