WebAssembly

Use Fatima through the WebAssembly JSON API and a JavaScript host.

The WebAssembly crate exposes Core through one async JSON function:

handle_api_request_json(input: string, host: unknown): Promise<string>

Most users should call @fatima.dev/js instead of using this function directly.

Host functions

The host object supplies everything WebAssembly cannot access by itself:

Function	Purpose
`envVars()`	Return all environment variables.
`envVar(key)`	Return one environment variable or `null`.
`currentDir()`	Return the working directory.
`exists(path)`	Check path existence.
`readText(path)`	Read a UTF-8 file.
`writeText(path, content)`	Write a UTF-8 file.
`createDirAll(path)`	Create directories recursively.
`removeFile(path)`	Remove a file.
`processId()`	Return a process id.
`runCommand(request)`	Run an external command.
`httpJson(request)`	Perform an HTTP request and return JSON.

Direct request

const response = JSON.parse(await handle_api_request_json(JSON.stringify({
  method: "secrets",
  params: { config: "fatima.json", environment: "development" },
}), host));

if (!response.ok) throw new Error(response.error);

Providers such as Vercel and Infisical require host support for commands or HTTP requests.