Client Guide
There are actually three separate clients shipped in restify:
- JsonClient: sends and expects application/json
- StringClient: sends url-encoded request and expects text/plain
- HttpClient: thin wrapper over node’s http/https libraries
The idea being that if you want to support “typical” control-plane
REST APIs, you probably want the JsonClient
, or if you’re using some
other serialization (like XML) you’d write your own client that
extends the StringClient
. If you need streaming support, you’ll need
to do some work on top of the HttpClient
, as StringClient
and
friends buffer requests/responses.
All clients support retry with exponential backoff for getting a TCP
connection; they do not perform retries on 5xx error codes like
previous versions of the restify client. You can set retry
to false
to
disable this logic altogether. Also, all clients support a connectTimeout
field, which is use on each retry. The default is not to set a
connectTimeout
, so you end up with the node.js socket defaults.
Here’s an example of hitting the Joyent CloudAPI:
var restify = require('restify-clients');
// Creates a JSON client
var client = restify.createJsonClient({
url: 'https://us-east-1.api.joyent.com'
});
client.basicAuth('$login', '$password');
client.get('/my/machines', function(err, req, res, obj) {
assert.ifError(err);
console.log(JSON.stringify(obj, null, 2));
});
As a short-hand, a client can be initialized with a string-URL rather than an options object:
var restify = require('restify-clients');
var client = restify.createJsonClient('https://us-east-1.api.joyent.com');
Note that all further documentation refers to the “short-hand” form of
methods like get/put/del
which take a string path. You can also
pass in an object to any of those methods with extra params (notably
headers):
var options = {
path: '/foo/bar',
headers: {
'x-foo': 'bar'
},
retry: {
'retries': 0
},
agent: false
};
client.get(options, function(err, req, res) { .. });
If you need to interpose additional headers in the request before it is sent on
to the server, you can provide a synchronous callback function as the
signRequest
option when creating a client. This is particularly useful with
node-http-signature, which
needs to attach a cryptographic signature of selected outgoing headers. If
provided, this callback will be invoked with a single parameter: the outgoing
http.ClientRequest
object.
JsonClient
The JSON Client is the highest-level client bundled with restify-clients; it
exports a set of methods that map directly to HTTP verbs. All
callbacks look like function(err, req, res, [obj])
, where obj
is
optional, depending on if content was returned. HTTP status codes are
not interpreted, so if the server returned 4xx or something with a
JSON payload, obj
will be the JSON payload. err
however will be
set if the server returned a status code >= 400 (it will be one of the
restify HTTP errors). If obj
looks like a RestError
:
{
"code": "FooError",
"message": "some foo happened"
}
then err
gets “upconverted” into a RestError
for you. Otherwise
it will be an HttpError
.
createJsonClient(options)
var client = restify.createJsonClient({
url: 'https://api.us-east-1.joyent.com',
version: '*'
});
Options:
Name | Type | Description |
---|---|---|
accept | String | Accept header to send |
connectTimeout | Number | Amount of time to wait for a socket |
requestTimeout | Number | Amount of time to wait for the request to finish |
dtrace | Object | node-dtrace-provider handle |
gzip | Object | Will compress data when sent using content-encoding: gzip |
headers | Object | HTTP headers to set in all requests |
log | Object | bunyan instance |
retry | Object | options to provide to node-retry;”false” disables retry; defaults to 4 retries |
signRequest | Function | synchronous callback for interposing headers before request is sent |
url | String | Fully-qualified URL to connect to |
userAgent | String | user-agent string to use; restify inserts one, but you can override it |
version | String | semver string to set the accept-version |
get(path, callback)
Performs an HTTP get; if no payload was returned, obj
defaults to
{}
for you (so you don’t get a bunch of null pointer errors).
client.get('/foo/bar', function(err, req, res, obj) {
assert.ifError(err);
console.log('%j', obj);
});
head(path, callback)
Just like get
, but without obj
:
client.head('/foo/bar', function(err, req, res) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
});
post(path, object, callback)
Takes a complete object to serialize and send to the server.
client.post('/foo', { hello: 'world' }, function(err, req, res, obj) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
console.log('%j', obj);
});
put(path, object, callback)
Just like post
:
client.put('/foo', { hello: 'world' }, function(err, req, res, obj) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
console.log('%j', obj);
});
del(path, callback)
del
doesn’t take content, since you know, it should’t:
client.del('/foo/bar', function(err, req, res) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
});
StringClient
StringClient
is what JsonClient
is built on, and provides a base
for you to write other buffering/parsing clients (like say an XML
client). If you need to talk to some “raw” HTTP server, then
StringClient
is what you want, as it by default will provide you
with content uploads in application/x-www-form-url-encoded
and
downloads as text/plain
. To extend a StringClient
, take a look at
the source for JsonClient
. Effectively, you extend it, and set the
appropriate options in the constructor and implement a write
(for
put/post) and parse
method (for all HTTP bodies), and that’s it.
createStringClient(options)
var client = restify.createStringClient({
url: 'https://example.com'
})
get(path, callback)
Performs an HTTP get; if no payload was returned, data
defaults to
''
for you (so you don’t get a bunch of null pointer errors).
client.get('/foo/bar', function(err, req, res, data) {
assert.ifError(err);
console.log('%s', data);
});
head(path, callback)
Just like get
, but without data
:
client.head('/foo/bar', function(err, req, res) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
});
post(path, object, callback)
Takes a complete object to serialize and send to the server.
client.post('/foo', { hello: 'world' }, function(err, req, res, data) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
console.log('%s', data);
});
put(path, object, callback)
Just like post
:
client.put('/foo', { hello: 'world' }, function(err, req, res, data) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
console.log('%s', data);
});
del(path, callback)
del
doesn’t take content, since you know, it should’t:
client.del('/foo/bar', function(err, req, res) {
assert.ifError(err);
console.log('%d -> %j', res.statusCode, res.headers);
});
HttpClient
HttpClient
is the lowest-level client shipped in restify, and is
basically just some sugar over the top of node’s http/https modules
(with HTTP methods like the other clients). It is useful if you want
to stream with restify. Note that the event below is unfortunately
named result
and not response
(because
Event ‘response’
is already used).
client = restify.createClient({
url: 'http://127.0.0.1'
});
client.get('/str/mcavage', function(err, req) {
assert.ifError(err); // connection error
req.on('result', function(err, res) {
assert.ifError(err); // HTTP status code >= 400
res.body = '';
res.setEncoding('utf8');
res.on('data', function(chunk) {
res.body += chunk;
});
res.on('end', function() {
console.log(res.body);
});
});
});
Or a write:
client.post(opts, function(err, req) {
assert.ifError(connectErr);
req.on('result', function(err, res) {
assert.ifError(err);
res.body = '';
res.setEncoding('utf8');
res.on('data', function(chunk) {
res.body += chunk;
});
res.on('end', function() {
console.log(res.body);
});
});
req.write('hello world');
req.end();
});
Note that get/head/del all call req.end()
for you, so you can’t
write data over those. Otherwise, all the same methods exist as
JsonClient/StringClient
.
One wishing to extend the HttpClient
should look at the internals
and note that read
and write
probably need to be overridden.
Proxy
There are several options for enabling a proxy for the http client. The following options are available to set a proxy url:
// Set the proxy option in the client configuration
restify.createClient({
proxy: 'http://127.0.0.1'
});
From environment variables:
$ export HTTPS_PROXY = 'https://127.0.0.1'
$ export HTTP_PROXY = 'http://127.0.0.1'
There is an option to disable the use of a proxy on a url basis or for all urls. This can be enabled by setting an environment variable.
Don’t proxy requests to any urls
$ export NO_PROXY='*'
Don’t proxy requests to localhost
$ export NO_PROXY='127.0.0.1'
Don’t proxy requests to localhost on port 8000
$ export NO_PROXY='localhost:8000'
Don’t proxy requests to multiple IPs
$ export NO_PROXY='127.0.0.1, 8.8.8.8'
Note: The url being requested must match the full hostname in the proxy configuration or NO_PROXY environment variable. DNS lookups are not performed to determine the IP address of a hostname.
basicAuth(username, password)
Since it hasn’t been mentioned yet, this convenience method (available
on all clients), just sets the Authorization
header for all HTTP requests:
client.basicAuth('mark', 'mysupersecretpassword');
Upgrades
If you successfully negotiate an Upgrade with the HTTP server, an
upgradeResult
event will be emitted with the arguments err
, res
, socket
and head
. You can use this functionality to establish a WebSockets
connection with a server. For example, using the
watershed library:
var ws = new Watershed();
var wskey = ws.generateKey();
var options = {
path: '/websockets/attach',
headers: {
connection: 'upgrade',
upgrade: 'websocket',
'sec-websocket-key': wskey,
}
};
client.get(options, function(err, res, socket, head) {
res.once('upgradeResult', function(err2, res2, socket2, head2) {
var shed = ws.connect(res2, socket2, head2, wskey);
shed.on('text', function(msg) {
console.log('message from server: ' + msg);
shed.end();
});
shed.send('greetings program');
});
});
- Previous
- Next