Permissions

Deno's permission management API.

The class which provides the interface for the Deno.permissions global instance and is based on the web platform Permissions API, though some proposed parts of the API which are useful in a server side runtime context were removed or abandoned in the web platform specification which is why it was chosen to locate it in the Deno namespace instead.

By default, if the stdin/stdout is TTY for the Deno CLI (meaning it can send and receive text), then the CLI will prompt the user to grant permission when an un-granted permission is requested. This behavior can be changed by using the --no-prompt command at startup. When prompting the CLI will request the narrowest permission possible, potentially making it annoying to the user. The permissions APIs allow the code author to request a wider set of permissions at one time in order to provide a better user experience.

An EventTarget returned from the Deno.permissions API which can provide updates to any state changes of the permission.

The permission descriptor for the allow-env and deny-env permissions, which controls access to being able to read and write to the process environment variables as well as access other information about the environment. The option variable allows scoping the permission to a specific environment variable.

The permission descriptor for the allow-ffi and deny-ffi permissions, which controls access to loading foreign code and interfacing with it via the Foreign Function Interface API available in Deno. The option path allows scoping the permission to a specific path on the host.

The permission descriptor for the allow-import and deny-import permissions, which controls access to importing from remote hosts via the network. The option host allows scoping the permission for outbound connection to a specific host and port.

The permission descriptor for the allow-net and deny-net permissions, which controls access to opening network ports and connecting to remote hosts via the network. The option host allows scoping the permission for outbound connection to a specific host and port.

A set of options which can define the permissions within a test or worker context at a highly specific level.

The interface which defines what event types are supported by PermissionStatus instances.

The permission descriptor for the allow-read and deny-read permissions, which controls access to reading resources from the local host. The option path allows scoping the permission to a specific path (and if the path is a directory any sub paths).

Permission granted under allow-read only allows runtime code to attempt to read, the underlying operating system may apply additional permissions.

The permission descriptor for the allow-run and deny-run permissions, which controls access to what sub-processes can be executed by Deno. The option command allows scoping the permission to a specific executable.

Warning, in practice, allow-run is effectively the same as allow-all in the sense that malicious code could execute any arbitrary code on the host.

The permission descriptor for the allow-sys and deny-sys permissions, which controls access to sensitive host system information, which malicious code might attempt to exploit. The option kind allows scoping the permission to a specific piece of information.

The permission descriptor for the allow-write and deny-write permissions, which controls access to writing to resources from the local host. The option path allow scoping the permission to a specific path (and if the path is a directory any sub paths).

Permission granted under allow-write only allows runtime code to attempt to write, the underlying operating system may apply additional permissions.

Permission descriptors which define a permission and can be queried, requested, or revoked.

View the specifics of the individual descriptors for more information about each permission kind.

The name of a privileged feature which needs permission.

Options which define the permissions within a test or worker context.

"inherit" ensures that all permissions of the parent process will be applied to the test context. "none" ensures the test context has no permissions. A PermissionOptionsObject provides a more specific set of permissions to the test context.

The current status of the permission:

• "granted" - the permission has been granted.
• "denied" - the permission has been explicitly denied.
• "prompt" - the permission has not explicitly granted nor denied.

Deno's permission management API.

It is a singleton instance of the Permissions object and is based on the web platform Permissions API, though some proposed parts of the API which are useful in a server side runtime context were removed or abandoned in the web platform specification which is why it was chosen to locate it in the Deno namespace instead.

By default, if the stdin/stdout is TTY for the Deno CLI (meaning it can send and receive text), then the CLI will prompt the user to grant permission when an un-granted permission is requested. This behavior can be changed by using the --no-prompt command at startup. When prompting the CLI will request the narrowest permission possible, potentially making it annoying to the user. The permissions APIs allow the code author to request a wider set of permissions at one time in order to provide a better user experience.

Requesting already granted permissions will not prompt the user and will return that the permission was granted.

Querying

const status = await Deno.permissions.query({ name: "read", path: "/etc" });
console.log(status.state);

const status = Deno.permissions.querySync({ name: "read", path: "/etc" });
console.log(status.state);

Revoking

import { assert } from "jsr:@std/assert";

const status = await Deno.permissions.revoke({ name: "run" });
assert(status.state !== "granted")

import { assert } from "jsr:@std/assert";

const status = Deno.permissions.revokeSync({ name: "run" });
assert(status.state !== "granted")

Requesting

const status = await Deno.permissions.request({ name: "env" });
if (status.state === "granted") {
  console.log("'env' permission is granted.");
} else {
  console.log("'env' permission is denied.");
}

const status = Deno.permissions.requestSync({ name: "env" });
if (status.state === "granted") {
  console.log("'env' permission is granted.");
} else {
  console.log("'env' permission is denied.");
}