Interfaces for IO that make use of promises.
Q-IO now subsumes all of Q-HTTP and Q-FS.
The Q-IO package does not export a main module. You must reach in
directly for q-io/fs
, q-io/http
, and q-io/http-apps
.
var FS = require("q-io/fs");
File system API for Q promises with method signatures patterned after CommonJS/Fileystem/A but returning promises and promise streams.
Open returns a promise for either a buffer or string Reader or a Writer depending on the flags.
The options can be omitted, abbreviated to a flags
string, or expanded
to an options
object.
flags
:r
,w
,a
,b
, default ofr
, not bytewisecharset
: default ofutf-8
bufferSize
: in bytesmode
: UNIX permissionsbegin
first byte to read (defaults to zero)end
one past the last byte to read.end - begin == length
read
is a shortcut for opening a file and reading the entire contents
into memory. It returns a promise for the whole file contents. By
default, read
provides a string decoded from UTF-8. With the bytewise
mode flag, provides a Buffer
.
The options argument is identical to that of open
.
return FS.read(__filename, "b")
.then(function (content) {
// ...
})
return FS.read(__filename, {
flags: "b"
})
write
is a shortcut for opening a file and writing its entire content
from a single string or buffer.
The options are identical to that of open
, but the "w" flag is
implied, and the "b" flag is implied if the content is a buffer.
return FS.write("hello.txt", "Hello, World!\n")
.then(function () {
return FS.read("hello.txt")
})
.then(function (hello) {
expect(hello).toBe("Hello, World!\n")
})
append
is a shorthand for opening a file for writing from the end of
the existing content from a single string or buffer.
The options are identical to that of open
, but the "w+" flags are
implied, and the "b" flag is implied if the content is a buffer.
Copies a single file from one path to another. The target must be the full path, including the file name. Unlike at the shell, the file name is not inferred from the source path if the target turns out to be a directory.
Returns a promise for the completion of the operation.
Copies a file or tree of files from one path to another. Symbolic links are copied but not followed.
Returns a promise for the completion of the operation.
Returns a promise for a list of file names in a directory. The file names are relative to the given path.
Returns a promise for a list of files in a directory and all the directories it contains. Does not follow symbolic links.
The second argument is an optional guard function that determines what files to include and whether to traverse into another directory. It receives the path of the file, relative to the starting path, and also the stats object for that file. The guard must return a value like:
true
indicates that the entry should be includedfalse
indicates that the file should be excluded, but should still be traversed if it is a directory.null
indiciates that a directory should not be traversed.
Returns a promise for a deep list of directories.
Makes a directory at a given path. Fails if the parent directory does not exist. Returns a promise for the completion of the operation.
The mode is an optional Unix mode as an integer or string of octal digits.
Finishes a path of directories. For any branch of the path that does not exist, creates a directory. Fails if any branch of the path already exists but is not a directory.
Makes any directories with the given Unix mode.
Removes a file at the given path. Fails if a directory exists at the given path or if no file exists at the path.
Removes a file or directory at a given path, recursively removing any contained files and directories, without following symbolic links.
Moves a file or directory from one path to another using the underlying
rename(2)
implementation, thus it cannot move a file across devices.
Moves a file or directory from one path to another. If the source and
target are on different devices, falls back to copying and removing,
using copyTree(source, target)
and, if completely successful,
removeTree(source)
.
Creates a hard link from the source
Creates a relative symbolic link from the target to the source with an effect that resembles copying a file.
The type is important for Windows. It is "file" by default, but may be "directory" or "junction".
Creates a symbolic link at the target path. The link may be absolute or relative. The type must be "file", "directory", or "junction" and is mandatory to encourage Windows portability.
Changes the owner for a path using Unix user-id and group-id numbers.
Changes the Unix mode for a path. Returns a promise.
Follows all symbolic links along a path and returns a promise for the
metadata about a path as a Stats
object. The Stats object implements:
size
the size of the file in bytesisDirectory()
: returns whether the path refers to a directory with entries for other paths.isFile()
: returns whether the path refers to a file physically stored by the file system.isBlockDevice()
: returns whether the path refers to a Unix device driver, in which case there is no actual data in storage but the operating system may allow you to communicate with the driver as a blocks of memory.isCharacterDevice()
: returns whether the path refers to a Unix device driver, in which case there is no actual data in storage but the operating system may allow you to communicate with the driver as a stream.isSymbolicLink()
: returns whether the path refers to a symbolic link or junction. Stats for symbolic links are only discoverable throughstatLink
sincestat
follows symbolic links.isFIFO()
: returns whether the path refers to a Unix named pipe.isSocket()
: returns whether the path refers to a Unix domain socket.lastModified()
: returns the last time the path was opened for writing as aDate
lastAccessed()
: returns the last time the path was opened for reading or writing as aDate
Returns a promise for the Stats
for a path without following symbolic
links.
Returns a promise for the Stats
for a Unix file descriptor number.
Follows symbolic links and returns a promise for whether an entry exists at a given path.
Follows symbolic links and returns a promise for whether a file exists at a given path and does not cause an exception if nothing exists at that path.
Follows symbolic links and returns a promise for whether a directory exists at a given path and does not cause an exception if nothing exists at that path.
Returns a promise for whether a symbolic link exists at a given path and does not cause an exception if nothing exists at that path.
Follows symbolic links and returns a promise for the Date
when the
entry at the given path was last opened for writing, but causes an
exception if no file exists at that path.
Follows symbolic links and returns a promise for the Date
when the
entry at the given path was last opened for reading or writing, but
causes an exception if no file exists at that path.
Splits a path into the names of entries along the path. If the path is absolute, the first component is either a drive (with a colon) on Windows or an empty string for the root of a Unix file system.
Joins a sequence of paths into a single normalized path. All but the last path are assumed to refer to directories.
Like join but treats each path like a relative URL, so a terminating slash indicates that a path is to a directory and the next path begins at that directory.
Takes a single path or sequence of paths and joins them into a single
path, eliminating self .
and parent ..
entries when possible.
Joins and normalizes a path from the current working directory, returning a string.
Returns a promise for the absolute, canonical location of a given path, following symbolic links and normalizing path components. An entry does not need to exist at the end of the path.
Returns a promise for the path string of a symbolic link at a given path.
For any two absolute or relative paths, computes whether the parent path is an ancestor of the child path.
Returns a promise for the relative path from one path to another using
..
parent links where necessary. This operation is asynchronous
because it is necessary to determine whether the source path refers to a
directory or a file.
Assuming that the source path refers to a file, returns a string for the relative path from the source to the target path.
Assuming that the source path refers to a directory, returns a string for the relative path from the source to the target path.
Returns whether a path begins at the root of a Unix file system or a Windows drive.
Returns whether a path does not begin at the root of a Unix file system or Windows drive.
Returns whether a path is to the root of a Unix file system or a Windows drive.
Returns the Windows drive that contains a given path, or the root of a Unix file system.
Returns the path to the directory containing the given path.
Returns the last entry of a path. If an extension is provided and matches the extension of the path, removes that extension.
Returns the extension for a path (everything following the last dot .
in a path, unless that dot is at the beginning of the entry).
Returns an attenuated file system that uses the given path as its root. The resulting file system object is identical to the parent except that the child cannot open any file that is not within the root. Hard links are effectively inside the root regardless, but symbolic links cannot be followed outside of the jail.
Reads every file in the file system under a given path and returns a promise for an object that contains the absolute path and a Buffer for each of those files.
Not yet implemented
Not yet implemented
Q-IO provides a mock filesystem interface. The mock filesystem has the same interface as the real one and has most of the same features, but operates on a purely in-memory, in-process, in-javascript filesystem.
A mock filesystem can be created from a data structure. Objects are directories. Keys are paths. A buffer is a fileโs contents. Anything else is coerced to a string, then to a buffer in the UTF-8 encoding.
var MockFs = require("q-io/fs-mock");
var mockFs = MockFs({
"a": {
"b": {
"c.txt": "Content of a/b/c.txt"
}
},
"a/b/d.txt": new Buffer("Content of a/b/d.txt", "utf-8")
})
You can also instantiate a mock file system with the content of a subtree of a real file system. You receive a promise for the mock filesystem.
var FS = require("q-io/fs");
FS.mock(__dirname)
.then(function (fs) {
//
})
.done();
The HTTP module resembles CommonJS/JSGI.
var HTTP = require("q-io/http");
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.
The http
module exports a request
function that returns a promise
for a response.
- accepts a request object or a URL string.
- returns a promise for a response object.
The http
module exports a read
function, analogous to
Fs.read(path)
, but returning a promise for the content of an OK HTTP
response.
- accepts a request object 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.
- coerces URLs into request objects.
- completes an incomplete request object based on its
url
.
- coerces strings, arrays, and other objects supporting
forEach
into proper response objects. - if it receives
undefined
, it returnsundefined
. This is used as a singal to the requester that the responder has taken control of the response stream.
A complete request object has the following properties.
url
the full URL of the request as a stringpath
the full path as a stringscriptName
the routed portion of the path, like""
forhttp://example.com/
if no routing has occurred.pathInfo
the part of the path that remains to be routed, like/
forhttp://example.com
orhttp://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"
in case of default ports (80 or 443), otherwise likeexample.com:8080
hostname
like"example.com"
port
the port number, like80
remoteHost
remotePort
headers
corresponding values, possibly an array for multiple headers of the same name.agent
a custom node HTTP or HTTPS agent. HTTP and HTTPS agents can implement custom socket pools, allow use of SSL client certificates and self-signed certificates.body
an array of string or node bufferstimeout
an optional socket timeout in miliseconds to thread through to the HTTP agent.node
the wrapped Node request objectcancelled
a promise that indicates by rejection that the HTTP request should be aborted and the response promise should be rejected with the given error. Such a promise must not be fulfilled.
A complete response object has the following properties.
status
the HTTP status code as a number, like200
.headers
body
anyforEach
able, such as an array of stringsonclose
is an optional function that this library will call when a response concludes.node
the wrapped Node response object.
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 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.
- accepts a chunk as either a string or a
- 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
- accepts a
- 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 byq-io
. read()
- returns a promise for the entire body as a string or a buffer.
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 instances have the following methods:
read()
forEach(callback)
close()
node
the underlying node reader
Additionally, the Reader
constructor has the following methods:
read(stream, 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 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.
var BufferStream = require("q-io/buffer-stream");
var stream = BufferStream(new Buffer("Hello, World!\n", "utf-8"), "utf-8")
The HTTP applications module provides a comprehensive set of JSGI-alike
applications and application factories, suitable for use with the http
server and client.
var Apps = require("q-io/http-apps");
Creates an HTTP 200 Ok
response with the given content, content type,
and status.
The content may be a string, buffer, array of strings, array of buffers,
a readable stream of strings or buffers, or (generally) anything that
implements forEach
.
The default content type is text/plain
.
The default status is 200
.
An application that returns an HTTP 400 Bad request
response for any
request.
An application that returns an HTTP 404 Not found
response for any
request.
An application that returns an HTTP 405 Method not allowed
response
for any request. This is suitable for any endpoint where there is no
viable handler for the request method.
An application that returns an HTTP 406 Not acceptable
response for
any request. This is suitable for any situation where content
negotiation has failed, for example, if you cannot response with any of
the accepted encoding, charset, or language.
Not to be confused with an HTTP application, this is a utility that generates redirect responses.
The returns response issues a redirect to the given location. The utility fully qualifies the location.
This particular method should be used directly to generate an HTTP 301 Temporary redirect
response, but passing 307
in the status argument
turns it into an HTTP 307 Permanent redirect
response.
This particular method should be used to send all requests to a specific
location, but setting the tree
argument to true
causes the redirect
to follow the remaining unrouted path from the redirect location, so if
you move an entire directory tree from one location to another, this
redirect can forward to all of them.
Produces an HTTP 301 Temporary redirect
from one directory tree to
another, using redirect
.
Produces an HTTP 307 Permanent redirect
to a given location, using
redirect
.
Produces an HTTP 307 Permanent redirect
from one directory tree to
another, using redirect
.
Produces an HTTP response with the file at a given path. By default, it infers the content type from the extension of the path.
The file utility produces an e-tag
header suitable for cache control,
and may produce an HTTP 304 Not modified
if the requested resource has
the same entity tag.
The file utility may produce an HTTP 206 Partial content
response with
a content-range
header if the request has a range
header. If the
partial range request cannot be satisified, it may respond HTTP 416 Not satisfiable
.
In all cases, the response body is streamed from the file system.
Computes an entity tag for a file system Stats
object, using the
node.ino
, size
, and last modification time.
This is not yet implemented.
Returns an HTTP 200 Ok
response from some JSON, using the same
argumensts as JSON.stringify
.
A factory that produces an HTTP application that will always respond
with the given content, content type, and status. The default content
type is text/plain
and the default status is 200
.
The body may be a string, array of strings or buffers, or a readable stream of strings or buffers.
A factory that produces an HTTP application that will always respond
with the file at the given path. The content type is inferred from the
path extension by default, but can be overridden with contentType
.
A factory that produces an HTTP application that responds to all requests with files within a branch of the file system starting at the given path and using any unprocessed portion of the request location.
Options include:
notFound(request, response)
: alternate 404 responder, defaults toHttpApps.notFound
file(request, path, contentType, fs)
: alternate file responder, defaults toHttpApps.file
contentType
: forces the content type of file requests, forwarded to thefile
handler.directory(request, path, contentType, fs)
: alternate directory responder, defaults toHttpApps.directory
.redirectSymbolicLinks
: directs the client to use a redirect response for symbolic links instead of following links internally.permanent
: symbolic links that are turned into HTTP redirects will be permanent.followInsecureSymbolicLinks
: directsFileTree
to serve files that are outside the root path of the file tree if a symbolic link traverses there.fs
: alternate file system, defaults to thefs
module.
A factory that produces an HTTP application that temporarily redirects to the given path.
A factory that produces an HTTP application that redirects all requests under the requested path to parallel locations at the given path.
A factory that produces an HTTP application that redirects all requests to an exact location and instructs the requester's cache never to ask again.
A factory that produces an HTTP application that redirects all requests under the request path to a parallel location under the given path and instructs the requester's cache never to ask again.
A factory that produces an HTTP application that will cause an HTTP 404 Not found
response if the request has not reached the end of its route
(meaning pathInfo
is not ""
or "/"
), or will forward to the given
application.
Several routing application factories have the same form. They all take an object as their first argument and an optional fallback application as their second. The object maps each of the supported options for keys to an HTTP application for handling that option.
- Branch(paths, notFound) routes the next unprocessed path component
- Method(methods, notFound) routes the HTTP method. Methods are upper-case.
- ContentType(contentTypes, notAcceptable) routes based on the "accept" request header and produces a "content-type" response header.
- Langauge(languages, notAcceptable) routes based on the "accept-language" header and produces a "language" response header.
- Charaset(charsets, notAcceptable) routes based on the "accept-charset" header and produces a "charset" response header.
- Encoding(encodings, notAcceptable) routes based on the "accept-encoding" request header and produces an "encoding" response header.
- Host(hosts, notFound) routes based on the host name of the request "host" header, which defaults to "*". This is equivalent to virtual host mapping.
Produces an HTTP application that uses a function to determine the next
application to route. The selector
is a function that accepts the
request and returns an HTTP application.
Returns an HTTP application that attempts to respond with each of a
series of applications and returns the first response that does not have
a 404 Not found
status, or whatever response comes last.
Wraps an application such that any exceptions get converted into HTTP 500 Server error
responses. If debug
is enabled, produces the
exception and stack traces in the body of the response.
Wraps an application such that request and response times are logged.
The log
function reports to console.log
by default. The
stamp(message)
function prefixes an ISO time stamp by default.
Adds an x-response-time
header to the response, with the time from receiving
starting the request to starting the response in miliseconds.
Adds a date
header to the response with the current date for cache
control purposes.
Wraps an application such that the tap
function receives the request
first. If the tap returns nothing, the request goes to the app
. If
the tap
returns a response, the app
never gets called.
Wraps an application such that the trap
function receives the
response. If it returns nothing, the response if forwarded. If the
trap
returns a response, the original response is discarded.
Wraps an application such that the query string is parsed and placed in
request.parse
.
Use npm run cover
to generate and view a coverage report of Q-IO.
File | Percentage | Missing |
---|---|---|
fs-boot.js |
87% | 41 |
fs.js |
72% | 100 |
reader.js |
94% | 8 |
writer.js |
91% | 8 |
fs-common.js |
87% | 52 |
fs-root.js |
88% | 11 |
fs-mock.js |
91% | 46 |
buffer-stream.js |
89% | 6 |
http.js |
93% | 25 |
http-apps.js |
80% | 286 |
http-cookie.js |
79% | 15 |
Copyright 2009โ2013 Kristopher Michael Kowal MIT License (enclosed)