Files

Read, write, upload, and download runtime files.

FileManager declaration

class FileManager

FileManager access

This type is created by the SDK; do not construct it directly.

const manager = runtime.files;

FileManager methods

download()

Download a runtime file or directory without buffering it in memory.

FileManager.download(src: string, dst: string): Promise<void>

Parameters

Name	Type	Default	Description
src	string	Required	Source path inside the runtime.
dst	string	Required	Local destination path. A trailing slash or existing directory downloads beneath that directory using the source basename.

Returns

• Promise<void>

Examples

await runtime.files.download("/workspace/results", "./artifacts/");

read()

Read a file from the runtime as bytes.

FileManager.read(path: string, maxBytes?: number | null): Promise<Uint8Array<ArrayBufferLike>>

Parameters

Name	Type	Default	Description
path	string	Required	Path inside the runtime.
maxBytes?	number | null	Optional	Maximum number of bytes to return.

Returns

• Promise<Uint8Array<ArrayBufferLike>>

readText()

Read a UTF-8 text file from the runtime.

FileManager.readText(path: string, maxBytes?: number | null): Promise<string>

Parameters

Name	Type	Default	Description
path	string	Required	Absolute path inside the runtime.
maxBytes?	number | null	Optional	Optional maximum number of bytes to read.

Returns

• Promise<string> — Decoded UTF-8 text.

Examples

const packageJson = await runtime.files.readText("/workspace/package.json");
console.log(JSON.parse(packageJson).name);

upload()

Stream a local file or directory to the runtime without buffering it in memory.

Files are committed through a temporary sibling after their byte count is verified. Directories are extracted into a staging directory and moved into place only after the complete archive arrives.

FileManager.upload(src: string, dst: string): Promise<void>

Parameters

Name	Type	Default	Description
src	string	Required	Local source path.
dst	string	Required	Destination path inside the runtime.

Returns

• Promise<void>

Throws

• Error If the local source is not a file or directory.

Examples

await runtime.files.upload("./src", "/workspace/src");
await runtime.files.upload("./build.tar.zst", "/workspace/artifacts/");

write()

Write bytes or text to a runtime file.

FileManager.write(
  path: string,
  content: string | Uint8Array<ArrayBufferLike>,
  options: { executable?: boolean } = {},
): Promise<void>

Parameters

Name	Type	Default	Description
path	string	Required	Path inside the runtime.
content	string | Uint8Array<ArrayBufferLike>	Required	Bytes or text to write.
options	{ executable?: boolean }	{}	Options that control the operation.

Returns

• Promise<void>