Q-IO

Interfaces for IO that make use of promises.

Q-IO now subsumes all of Q-HTTP and Q-FS.

Filesystem

File system API for Q promises with method signatures patterned after CommonJS/Fileystem/A but returning promises and promise streams.

open(path, options)

Options is an optional object.

• flags: r, w, a, b, default of r, not binary
• charset: default of utf-8
• bufferSize: in bytes
• mode: UNIX permissions
• begin first byte to read (defaults to zero)
• end one past the last byte to read. end - begin == length

Open returns a promise for either a Reader or a Writer depending on the given flags.

read(path, options)

write(path, content, options)

append(path, content, options)

copy(source, target)

copyTree(source, target)

list(path)

listTree(path, guard(path, stat))

listDirectoryTree(path)

makeDirectory(path)

makeTree(path)

remove(path)

removeTree(path)

move(source, target)

link(source, taget)

symbolicCopy(source, target)

symbolicLink(target, relative, type)

chown(path, uid, gid)

chmod(path, mode)

stat(path)

statLink(path)

statFd(fd)

exists(path)

isFile(path)

isDirectory(path)

lastModified(path)

split(path)

join(paths)

join(...paths)

resolve(...paths)

normal(...paths)

absolute(path)

canonical(path)

readLink(path)

contains(parent, child)

relative(source, target)

relativeFromFile(source, target)

relativeFromDirectory(source, target)

isAbsolute(path)

isRelative(path)

isRoot(path)

root(path)

directory(path)

base(path, extension)

extension(path)

reroot(path)

toObject(path)

glob(pattern)

Not yet implemented

match(pattern, path)

Not yet implemented

HTTP

The HTTP module resembles CommonJS/JSGI.

Server(app)

The http module exports a Server constructor.

• accepts an application, returns a server.
• calls the application function when requests are received.
  • if the application returns a response object, sends that response.
• listen(port)
  • accepts a port number.
  • returns a promise for undefined when the server has begun listening.
• stop()
  • returns a promise for undefined when the server has stopped.

request(request object or url)

The http module exports a request function that returns a promise for a response.

• accepts a request or a URL string.
• returns a promise for a response.

read(request object or url)

The http module exports a read function, analogous to Fs.read(path), but returning a promise for the contento of an OK HTTP response.

• accepts a request or a URL string.
• returns a promise for the response body as a string provided that the request is successful with a 200 status.
  • rejects the promise with the response as the reason for failure if the request fails.

normalizeRequest(request object or url)

• coerces URLs into request objects.
• completes an incomplete request object based on its url.

normalizeResponse(response)

• coerces strings, arrays, and other objects supporting forEach into proper response objects.
• if it receives undefined, it returns undefined. This is used as a singal to the requester that the responder has taken control of the response stream.

request

A complete request object has the following properties.

• url the full URL of the request as a string
• path the full path as a string
• scriptName the routed portion of the path, like "" for http://example.com/ if no routing has occurred.
• pathInfo the part of the path that remains to be routed, like / for http://example.com or http://example.com/ if no routing has occurred.
• version the requested HTTP version as an array of strings.
• method like "GET"
• scheme like "http:"
• host like "example.com"
• port the port number, like 80
• remoteHost
• remotePort
• headers corresponding values, possibly an array for multiple headers of the same name.
• body
• node the wrapped Node request object

response

A complete response object has the following properties.

• status the HTTP status code as a number, like 200.
• headers
• body an IO reader
• onclose is an optional function that this library will call when a response concludes.
• node the wrapped Node response object.

headers

Headers are an object mapping lower-case header-names to corresponding values, possibly an array for multiple headers of the same name, for both requests and responses.

body

body is a representation of a readable stream, either for the content of a request or a response. It is implemented as a Q-IO reader.

• forEach(callback)
  • accepts a callback(chunk) function
    • accepts a chunk as either a string or a Buffer
    • returns undefined or a promise for undefined when the chunk has been flushed.
  • returns undefined or a promise for undefined when the stream is finished writing.
  • the forEach function for arrays of strings or buffers is sufficient for user-provided bodies
• the forEach function is the only necessary function for bodies provided to this library.
• in addition to forEach, bodies provided by this library support the entire readable stream interface provided by q-io.
• read()
  • returns a promise for the entire body as a string or a buffer.

application

An HTTP application is a function that accepts a request and returns a response. The request function itself is an application. Applications can be chained and combined to make advanced servers and clients.

• accepts a request
• returns a response, a promise for a response, or nothing if no response should be sent.

Reader

Reader instances have the following methods:

• read()
• forEach(callback)
• close()
• node the underlying node reader

Additionally, the Reader constructor has the following methods:

• read(tream, charset) accepts any foreachable and returns either a buffer or a string if given a charset.
• join(buffers) consolidates an array of buffers into a single buffer. The buffers array is collapsed in place and the new first and only buffer is returned.

The reader module exports a function that accepts a Node reader and returns a Q reader.

Writer

Writer instances have the following methods:

• write(content) writes a chunk of content, either from a string or a buffer.
• flush() returns a promise to drain the outbound content all the way to its destination.
• close()
• destroy()
• node the underlying node writer

The writer module exports a function that accepts a Node writer and returns a Q writer.

Copyright 2009–2012 Kristopher Michael Kowal MIT License (enclosed)