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The global namespace where Deno specific, non-standard APIs are located.

A set of error constructors that are raised by Deno APIs.

A controller object that allows you to abort one or more DOM requests as and when desired.

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.

An API for compressing a stream of data.

An API for decompressing a stream of data.

A variable-sized buffer of bytes with read() and write() methods.

Raised when attempting to open a server listener on an address and port that already has a listener.

Raised when the underlying operating system reports an EADDRNOTAVAIL error.

Raised when trying to create a resource, like a file, that already exits.

The underlying IO resource is invalid or closed, and so the operation could not be performed.

Raised when trying to write to a resource and a broken pipe error occurs. This can happen when trying to write directly to stdout or stderr and the operating system is unable to pipe the output for a reason external to the Deno runtime.

Raised when the underlying IO resource is not available because it is being awaited on in another block of code.

Raised when the underlying operating system reports an ECONNABORTED error.

Raised when the underlying operating system reports that a connection to a resource is refused.

Raised when the underlying operating system reports that a connection has been reset. With network servers, it can be a normal occurrence where a client will abort a connection instead of properly shutting it down.

Raised in situations where when attempting to load a dynamic import, too many redirects were encountered.

Raised when the underlying operating system reports an EINTR error. In many cases, this underlying IO error will be handled internally within Deno, or result in an @{link BadResource} error instead.

Raised when an operation to returns data that is invalid for the operation being performed.

Raised when the underlying operating system reports an ENOTCONN error.

Raised when the underlying operating system indicates that the file was not found.

Raised when the underlying Deno API is asked to perform a function that is not currently supported.

Raised when the underlying operating system indicates the current user which the Deno process is running under does not have the appropriate permissions to a file or resource, or the user did not provide required --allow-* flag.

Raised when the underlying operating system reports that an I/O operation has timed out (ETIMEDOUT).

Raised when attempting to read bytes from a resource, but the EOF was unexpectedly encountered.

Raised when expecting to write to a IO buffer resulted in zero bytes being written.

The Deno abstraction for reading and writing files.

Represents an instance of a sub process that is returned from Deno.run which can be used to manage the sub-process.

An event which takes place in the DOM.

EventTarget is a DOM interface implemented by objects that can receive events and may have listeners for them.

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

The location (URL) of the object it is linked to. Changes done on it are reflected on the object it relates to. Accessible via globalThis.location.

The MessageChannel interface of the Channel Messaging API allows us to create a new message channel and send data through it via its two MessagePort properties.

The MessagePort interface of the Channel Messaging API represents one of the two ports of a MessageChannel, allowing messages to be sent from one port and listening out for them arriving at the other.

Encapsulates a single performance metric that is part of the performance timeline. A performance entry can be directly created by making a performance mark or measure (for example by calling the .mark() method) at an explicit point in an application.

PerformanceMark is an abstract interface for PerformanceEntry objects with an entryType of "mark". Entries of this type are created by calling performance.mark() to add a named DOMHighResTimeStamp (the mark) to the performance timeline.

PerformanceMeasure is an abstract interface for PerformanceEntry objects with an entryType of "measure". Entries of this type are created by calling performance.measure() to add a named DOMHighResTimeStamp (the measure) between two marks to the performance timeline.

Events measuring progress of an underlying process, like an HTTP request (for an XMLHttpRequest, or the loading of the underlying resource of an , , , or ).

This Fetch API interface represents a resource request.

This Fetch API interface represents the response to a request.

The URL interface represents an object providing static methods used for creating object URLs.

The URLPattern API provides a web platform primitive for matching URLs based on a convenient pattern syntax.

The WebAssembly.CompileError object indicates an error during WebAssembly decoding or validation.

A WebAssembly.Global object represents a global variable instance, accessible from both JavaScript and importable/exportable across one or more WebAssembly.Module instances. This allows dynamic linking of multiple modules.

A WebAssembly.Instance object is a stateful, executable instance of a WebAssembly.Module. Instance objects contain all the Exported WebAssembly functions that allow calling into WebAssembly code from JavaScript.

The WebAssembly.LinkError object indicates an error during module instantiation (besides traps from the start function).

The WebAssembly.Memory object is a resizable ArrayBuffer or SharedArrayBuffer that holds the raw bytes of memory accessed by a WebAssembly Instance.

A WebAssembly.Module object contains stateless WebAssembly code that has already been compiled by the browser — this can be efficiently shared with Workers, and instantiated multiple times.

The WebAssembly.RuntimeError object is the error type that is thrown whenever WebAssembly specifies a trap.

The WebAssembly.Table() object is a JavaScript wrapper object — an array-like structure representing a WebAssembly Table, which stores function references. A table created by JavaScript or in WebAssembly code will be accessible and mutable from both JavaScript and WebAssembly.

Provides the API for creating and managing a WebSocket connection to a server, as well as for sending and receiving data on the connection.

A enum which defines the seek mode for IO related APIs that support seeking.

Returns the script arguments to the program. If for example we run a program:

Build related information.

A symbol which can be used as a key for a custom method which will be called when Deno.inspect() is called, or when the object is logged to the console.

An interface containing methods to interact with the process environment variables.

The Deno abstraction for reading and writing files.

The URL of the entrypoint module entered from the command-line.

Reflects the NO_COLOR environment variable at program start.

Deno's permission management API.

The current process ID of this instance of the Deno CLI.

The process ID of parent process of this instance of the Deno CLI.

A reference to stderr which can be used to write directly to stderr. It implements the Deno specific {@link Writer}, {@link WriterSync}, and {@link Closer} interfaces as well as provides a WritableStream interface.

A reference to stdin which can be used to read directly from stdin. It implements the Deno specific {@link Reader}, {@link ReaderSync}, and {@link Closer} interfaces as well as provides a ReadableStream interface.

A reference to stdout which can be used to write directly to stdout. It implements the Deno specific {@link Writer}, {@link WriterSync}, and {@link Closer} interfaces as well as provides a WritableStream interface.

Version related information.

Registers an event listener in the global scope, which will be called synchronously whenever the event type is dispatched.

Shows the given message and waits for the enter key pressed.

Decodes a string of data which has been encoded using base-64 encoding.

Creates a base-64 ASCII encoded string from the input string.

Cancels a timed, repeating action which was previously started by a call to setInterval()

Cancels a scheduled action initiated by setTimeout()

Shows the given message and waits for the answer. Returns the user's answer as boolean.

Registers the given function as a listener of the given signal event.

Change the current working directory to the specified path.

Changes the permission of a specific file/directory of specified path. Ignores the process's umask.

Synchronously changes the permission of a specific file/directory of specified path. Ignores the process's umask.

Change owner of a regular file or directory.

Synchronously change owner of a regular file or directory.

Close the given resource ID (rid) which has been previously opened, such as via opening or creating a file. Closing a file when you are finished with it is important to avoid leaking resources.

Connects to the hostname (default is "127.0.0.1") and port on the named transport (default is "tcp"), and resolves to the connection (Conn).

Establishes a secure connection over TLS (transport layer security) using an optional cert file, hostname (default is "127.0.0.1") and port. The cert file is optional and if not included Mozilla's root certificates will be used (see also https://github.com/ctz/webpki-roots for specifics)

Copies from src to dst until either EOF (null) is read from src or an error occurs. It resolves to the number of bytes copied or rejects with the first error encountered while copying.

Copies the contents and permissions of one file to another specified path, by default creating a new file if needed, else overwriting. Fails if target path is a directory or is unwritable.

Synchronously copies the contents and permissions of one file to another specified path, by default creating a new file if needed, else overwriting. Fails if target path is a directory or is unwritable.

Creates a file if none exists or truncates an existing file and resolves to an instance of Deno.FsFile.

Creates a file if none exists or truncates an existing file and returns an instance of Deno.FsFile.

Return a string representing the current working directory.

Returns the path to the current deno executable.

Exit the Deno process with optional exit code.

Flushes any pending data operations of the given file stream to disk.

const file = await Deno.open(
 "my_file.txt",
 { read: true, write: true, create: true },
);
await Deno.write(file.rid, new TextEncoder().encode("Hello World"));
await Deno.fdatasync(file.rid);
console.log(new TextDecoder().decode(await Deno.readFile("my_file.txt"))); // Hello World

Synchronously flushes any pending data operations of the given file stream to disk.

Returns a Deno.FileInfo for the given file stream.

Synchronously returns a Deno.FileInfo for the given file stream.

Flushes any pending data and metadata operations of the given file stream to disk.

Synchronously flushes any pending data and metadata operations of the given file stream to disk.

Truncates or extends the specified file stream, to reach the specified len.

Synchronously truncates or extends the specified file stream, to reach the specified len.

Get the hostname of the machine the Deno process is running on.

Converts the input into a string that has the same format as printed by console.log().

Check if a given resource id (rid) is a TTY (a terminal).

Turns a Reader, r, into an async iterator.

Turns a ReaderSync, r, into an iterator.

Send a signal to process under given pid.

Creates newpath as a hard link to oldpath.

Synchronously creates newpath as a hard link to oldpath.

Listen announces on the local transport address.

Listen announces on the local transport address over TLS (transport layer security).

Resolves to a Deno.FileInfo for the specified path. If path is a symlink, information for the symlink will be returned instead of what it points to.

Synchronously returns a Deno.FileInfo for the specified path. If path is a symlink, information for the symlink will be returned instead of what it points to.

Creates a new temporary directory in the default directory for temporary files, unless dir is specified. Other optional options include prefixing and suffixing the directory name with prefix and suffix respectively.

Synchronously creates a new temporary directory in the default directory for temporary files, unless dir is specified. Other optional options include prefixing and suffixing the directory name with prefix and suffix respectively.

Creates a new temporary file in the default directory for temporary files, unless dir is specified.

Synchronously creates a new temporary file in the default directory for temporary files, unless dir is specified.

Returns an object describing the memory usage of the Deno process and the V8 subsystem measured in bytes.

Receive metrics from the privileged side of Deno. This is primarily used in the development of Deno. Ops, also called bindings, are the go-between between Deno JavaScript sandbox and the rest of Deno.

Creates a new directory with the specified path.

Synchronously creates a new directory with the specified path.

Open a file and resolve to an instance of Deno.FsFile. The file does not need to previously exist if using the create or createNew open options. It is the caller's responsibility to close the file when finished with it.

Synchronously open a file and return an instance of Deno.FsFile. The file does not need to previously exist if using the create or createNew open options. It is the caller's responsibility to close the file when finished with it.

Read from a resource ID (rid) into an array buffer (buffer).

Read Reader r until EOF (null) and resolve to the content as Uint8Array`.

Synchronously reads Reader r until EOF (null) and returns the content as Uint8Array.

Reads the directory given by path and returns an async iterable of Deno.DirEntry.

Synchronously reads the directory given by path and returns an iterable of Deno.DirEntry.

Reads and resolves to the entire contents of a file as an array of bytes. TextDecoder can be used to transform the bytes to string if required. Reading a directory returns an empty data array.

Synchronously reads and returns the entire contents of a file as an array of bytes. TextDecoder can be used to transform the bytes to string if required. Reading a directory returns an empty data array.

Resolves to the full path destination of the named symbolic link.

Synchronously returns the full path destination of the named symbolic link.

Synchronously read from a resource ID (rid) into an array buffer (buffer).

Asynchronously reads and returns the entire contents of a file as an UTF-8 decoded string. Reading a directory throws an error.

Synchronously reads and returns the entire contents of a file as an UTF-8 decoded string. Reading a directory throws an error.

Resolves to the absolute normalized path, with symbolic links resolved.

Synchronously returns absolute normalized path, with symbolic links resolved.

Make the timer of the given id block the event loop from finishing.

Removes the named file or directory.

Removes the given signal listener that has been registered with Deno.addSignalListener.

Synchronously removes the named file or directory.

Renames (moves) oldpath to newpath. Paths may be files or directories. If newpath already exists and is not a directory, rename() replaces it. OS-specific restrictions may apply when oldpath and newpath are in different directories.

Synchronously renames (moves) oldpath to newpath. Paths may be files or directories. If newpath already exists and is not a directory, renameSync() replaces it. OS-specific restrictions may apply when oldpath and newpath are in different directories.

Returns a map of open resource IDs (rid) along with their string representations. This is an internal API and as such resource representation has unknown type; that means it can change any time and should not be depended upon.

Spawns new subprocess. RunOptions must contain at a minimum the opt.cmd, an array of program arguments, the first of which is the binary.

Seek a resource ID (rid) to the given offset under mode given by whence. The call resolves to the new position within the resource (bytes from the start).

Synchronously seek a resource ID (rid) to the given offset under mode given by whence. The new position within the resource (bytes from the start) is returned.

Services HTTP requests given a TCP or TLS socket.

Shutdown socket send operations.

Start TLS handshake from an existing connection using an optional list of CA certificates, and hostname (default is "127.0.0.1"). Specifying CA certs is optional. By default the configured root certificates are used. Using this function requires that the other end of the connection is prepared for a TLS handshake.

Resolves to a Deno.FileInfo for the specified path. Will always follow symlinks.

Synchronously returns a Deno.FileInfo for the specified path. Will always follow symlinks.

Creates newpath as a symbolic link to oldpath.

Creates newpath as a symbolic link to oldpath.

Register a test which will be run when deno test is used on the command line and the containing module looks like a test module.

Truncates (or extends) the specified file, to reach the specified len. If len is not specified then the entire file contents are truncated.

Synchronously truncates (or extends) the specified file, to reach the specified len. If len is not specified then the entire file contents are truncated.

Make the timer of the given id not block the event loop from finishing.

Used to upgrade an incoming HTTP request to a WebSocket.

Watch for file system events against one or more paths, which can be files or directories. These paths must exist already. One user action (e.g. touch test.file) can generate multiple file system events. Likewise, one user action can result in multiple file paths in one event (e.g. mv old_name.txt new_name.txt).

Write to the resource ID (rid) the contents of the array buffer (data).

Write all the content of the array buffer (arr) to the writer (w).

Synchronously write all the content of the array buffer (arr) to the writer (w).

Write data to the given path, by default creating a new file if needed, else overwriting.

Synchronously write data to the given path, by default creating a new file if needed, else overwriting.

Synchronously write to the resource ID (rid) the contents of the array buffer (data).

Write string data to the given path, by default creating a new file if needed, else overwriting.

Synchronously write string data to the given path, by default creating a new file if needed, else overwriting.

Dispatches an event in the global scope, synchronously invoking any registered event listeners for this event in the appropriate order. Returns false if event is cancelable and at least one of the event handlers which handled this event called Event.preventDefault(). Otherwise it returns true.

Fetch a resource from the network. It returns a Promise that resolves to the Response to that Request, whether it is successful or not.

Shows the given message and waits for the user's input. Returns the user's input as string.

A microtask is a short function which is executed after the function or module which created it exits and only if the JavaScript execution stack is empty, but before returning control to the event loop being used to drive the script's execution environment. This event loop may be either the main event loop or the event loop driving a web worker.

Remove a previously registered event listener from the global scope

Dispatch an uncaught exception. Similar to a synchronous version of:

setTimeout(() => { throw error; }, 0);

The error can not be caught with a try/catch block. An error event will be dispatched to the global scope. You can prevent the error from being reported to the console with Event.prototype.preventDefault():

addEventListener("error", (event) => {
  event.preventDefault();
});
reportError(new Error("foo")); // Will not be reported.

In Deno, this error will terminate the process if not intercepted like above.

Repeatedly calls a function , with a fixed time delay between each call.

Sets a timer which executes a function once after the timer expires. Returns an id which may be used to cancel the timeout.

Creates a deep copy of a given value using the structured clone algorithm.

The WebAssembly.compile() function compiles WebAssembly binary code into a WebAssembly.Module object. This function is useful if it is necessary to compile a module before it can be instantiated (otherwise, the WebAssembly.instantiate() function should be used).

The WebAssembly.compileStreaming() function compiles a WebAssembly.Module directly from a streamed underlying source. This function is useful if it is necessary to a compile a module before it can be instantiated (otherwise, the WebAssembly.instantiateStreaming() function should be used).

The WebAssembly.instantiate() function allows you to compile and instantiate WebAssembly code.

The WebAssembly.instantiateStreaming() function compiles and instantiates a WebAssembly module directly from a streamed underlying source. This is the most efficient, optimized way to load wasm code.

The WebAssembly.validate() function validates a given typed array of WebAssembly binary code, returning whether the bytes form a valid wasm module (true) or not (false).

A signal object that allows you to communicate with a DOM request (such as a Fetch) and abort it if required via an AbortController object.

This Streams API interface provides a built-in byte length queuing strategy that can be used when constructing streams.

The CryptoKey dictionary of the Web Crypto API represents a cryptographic key.

The CryptoKeyPair dictionary of the Web Crypto API represents a key pair for an asymmetric cryptography algorithm, also known as a public-key algorithm.

If resolveDns is called with "CAA" record type specified, it will return an array of this interface.

An abstract interface which when implemented provides an interface to close files/resources that were previously opened.

Information about a directory entry returned from Deno.readDir and Deno.readDirSync.

An interface containing methods to interact with the process environment variables.

Provides information about a file and is returned by Deno.stat, Deno.lstat, Deno.statSync, and Deno.lstatSync or from calling stat() and statSync() on an Deno.FsFile instance.

Represents a unique file system event yielded by a Deno.FsWatcher.

Returned by Deno.watchFs. It is an async iterator yielding up system events. To stop watching the file system by calling .close() method.

Option which can be specified when performing Deno.inspect.

A generic network listener for stream-oriented protocols.

Options which can be set when using Deno.makeTempDir, Deno.makeTempDirSync, Deno.makeTempFile, and Deno.makeTempFileSync.

Options which can be set when using Deno.mkdir and Deno.mkdirSync.

If resolveDns is called with "MX" record type specified, it will return an array of this interface.

If resolveDns is called with "NAPTR" record type specified, it will return an array of this interface.

Options which can be set when doing Deno.open and Deno.openSync.

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

An abstract interface which when implemented provides an interface to read bytes into an array buffer asynchronously.

An abstract interface which when implemented provides an interface to read bytes into an array buffer synchronously.

Options which can be set when using Deno.readFile or Deno.readFileSync.

Options which can be set when using Deno.remove and Deno.removeSync.

A map of open resources that Deno is tracking. The key is the resource ID (rid) and the value is its representation.

Options which can be used with Deno.run.

An abstract interface which when implemented provides an interface to seek within an open file/resource asynchronously.

An abstract interface which when implemented provides an interface to seek within an open file/resource synchronously.

UNSTABLE: new API, yet to be vetted.

If resolveDns is called with "SOA" record type specified, it will return an array of this interface.

If resolveDns is called with "SRV" record type specified, it will return an array of this interface.

Context that is passed to a testing function, which can be used to either gain information about the current test, or register additional test steps within the current test.

Specialized listener that accepts TLS connections.

Options for writing to a file.

An abstract interface which when implemented provides an interface to write bytes from an array buffer to a file/resource asynchronously.

An abstract interface which when implemented provides an interface to write bytes from an array buffer to a file/resource synchronously.

Lets web applications asynchronously read the contents of files (or raw data buffers) stored on the user's computer, using File or Blob objects to specify the file or data to read.

Provides a way to easily construct a set of key/value pairs representing form fields and their values, which can then be easily sent using the XMLHttpRequest.send() method. It uses the same format a form would use if the encoding type were set to "multipart/form-data".

This Fetch API interface allows you to perform various actions on HTTP request and response headers. These actions include retrieving, setting, adding to, and removing. A Headers object has an associated header list, which is initially empty and consists of zero or more name and value pairs. You can add to this using methods like append() (see Examples). In all methods of this interface, header names are matched by case-insensitive byte sequence.

Deno provides extra properties on import.meta. These are included here to ensure that these are still available when using the Deno namespace in conjunction with other type libs, like dom.

Deno supports User Timing Level 3 which is not widely supported yet in other runtimes.

Options which are used in conjunction with performance.mark. Check out the MDN performance.mark() documentation for more details.

Options which are used in conjunction with performance.measure. Check out the MDN performance.mark() documentation for more details.

This Streams API interface represents a readable stream of byte data. The Fetch API offers a concrete instance of a ReadableStream through the body property of a Response object.

This Web Storage API interface provides access to a particular domain's session or local storage. It allows, for example, the addition, modification, or deletion of stored data items.

This Web Crypto API interface provides a number of low-level cryptographic functions. It is accessed via the Crypto.subtle properties available in a window context (via Window.crypto).

URLPatternResult is the object returned from URLPattern.exec.

The GlobalDescriptor describes the options you can pass to new WebAssembly.Global().

The MemoryDescriptor describes the options you can pass to new WebAssembly.Memory().

A ModuleExportDescriptor is the description of a declared export in a WebAssembly.Module.

A ModuleImportDescriptor is the description of a declared import in a WebAssembly.Module.

The TableDescriptor describes the options you can pass to new WebAssembly.Table().

The value returned from WebAssembly.instantiate.

This Streams API interface provides a standard abstraction for writing streaming data to a destination, known as a sink. This object comes with built-in backpressure and queuing.

This Streams API interface represents a controller allowing control of a WritableStream's state. When constructing a WritableStream, the underlying sink is given a corresponding WritableStreamDefaultController instance to manipulate.

This Streams API interface is the object returned by WritableStream.getWriter() and once created locks the < writer to the WritableStream ensuring that no other streams can write to the underlying sink.

Additional information for FsEvent objects with the "other" kind.

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

The name of a privileged feature which needs permission.

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

The current status of the permission:

The status resolved from the .status() method of a Deno.Process instance.

The type of the resource record. Only the listed types are supported currently.

Operating signals which can be listened for or sent to sub-processes. What signals and what their standard behaviors are are OS dependent.

This type has been renamed to StructuredSerializeOptions. Use that type for new code.