Difference between revisions of "Rest API"

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Introduction

The Email & Apps Control Panel API provides most of the functions of the Control Panel through a REST-based web API. Whether it is adding a new customer account, adding mailboxes, or any other of the supported features the API allows your application to administer the changes regardless of your application's language or nature. For more information on RESTful web services refer to the following sites:

Paul James's Homepage: A RESTful Web service, an example

Wikipedia: Representational State Transfer - External Links

The API is accessible to all with access to Control Panel, including resellers, business customers, enterprise customers, and indirect customers. However, not all operations are available to non-resellers. See the Operations section for more details.

Operations

The following pages detail the operations that the API supports. The operations are grouped into sections based on the entity/object types that each operation interacts with. Non-resellers do not have access to all functions.

The examples shown in the operation pages are written in Ruby and extensively use the helper functions shown in the Ruby Examples below.

Quick Start

What you need:

• A Rackspace Email and Apps Control Panel admin account
• A HTTP class library that supports TLS and the HTTP methods: GET, POST, PUT, DELETE.

Making your first API call, an Show Customer request:

1. Obtain your API keys

   • Click on My Account at the top of the Control Panel web interface. Under the Administrators heading there will be an link for the API keys page.

2. Set up your client's HTTP request

   • Set up your client to make calls to a URL beginning with https://api.emailsrvr.com/v0.
   • Populate the Accept, User-Agent and X-Api-Signature HTTP request headers correctly. This is explained in detail here.

3. Make a GET request to /customers/me.

   • The complete URI will be https://api.emailsrvr.com/v0/customers/me. Use your HTTP library to retrieve the HTTP response code, 'x-error-message' HTTP response header and HTTP response body so that they may be displayed to help debug and determine success.

From here:

• Learn about the operations you'll be implementing at the subpages here.

Accessing the API

Your application will need to make HTTP requests to remote servers. Most programming languages have this function provided in its class library. In addition to the common GET and POST HTTP methods, the library used will also need to support PUT and DELETE.

Calls without TLS (formerly SSL) will complete successfully but it is HIGHLY RECOMMENDED that TLS always be used. Interception of unencrypted communication will allow a third party to have complete access to all functions available via the API.

For some language libraries just using an URL with https:// will cause the library to use TLS. In some other libraries however some options specific to the library may have to be configured to utilize TLS.

All API calls should be directed to a URL in the following format:

https://api.emailsrvr.com/(version)/(resource)

Example:

https://api.emailsrvr.com/v0/customers/12345678/domains/customerbusiness.com

Versions

The API version number is a component of the URL that is used to access the API. For example, to access the root of the API, the URL is https://api.emailsrvr.com/v0/. Bug fixes and minor non-breaking changes will be made without changing the version number. When major features or breaking changes are introduced, the version number will be incremented. It is not yet determined how many versions are going to be supported at any one time.

Authentication

To gain access to the API, your request must include a properly constructed X-Api-Signature HTTP header. Details on what to put in the header are below. To construct the header, you must have the following keys that that are generated from the Control Panel Web interface. The key generation page can be found by clicking 'My Account' at the top, then 'Generate API Keys' in the Administrators section.

An unsuccessful authentication will result in a 403 HTTP code.

X-Api-Signature Header

Format is as follows: <User Key>:<Timestamp>:<SHA1 Hash>
Example: eGbq9/2hcZsRlr1JV1Pi:20010317143725:46VIwd66mOFGG8IkbgnLlXnfnkU=

Remember to include the colons between the data strings!

User Key:
This is the public key issued by the Control Panel browser interface.

Timestamp:
The format is YYYYMMDDHHmmss. All values besides year are zero-padded to two spaces. For example, March 08th 2001 at 2:37.25pm would be 20010308143725.

SHA1 Hash:

A SHA1 (Secure Hash Algorithm) hash must be applied to a string with the following information:

<User Key><User Agent><Timestamp><Secret Key>

Note that the 'User Agent' must be the exact same as what is specified in the User-Agent HTTP header. Using the above example data, the string before hashing is:
eGbq9/2hcZsRlr1JV1PiRackspace Management Interface20010308143725QHOvchm/40czXhJ1OxfxK7jDHr3t

Resulting base-64 SHA1 Hash:
46VIwd66mOFGG8IkbgnLlXnfnkU=

Be sure to encode the binary hash, not the hex hash, into base-64. The resulting string should be 28 characters long.

Using the API

Requests

HTTP requests should be sent to the server with the correct URL, HTTP method, HTTP headers and form data (if needed). The URL specifies the resource, the HTTP method specifies what operation is done on the resource, and form data is used to specify the details of the resource when the resource is added or edited.

The URLs, corresponding HTTP methods, and necessary form data for the desired operations are detailed in the operation pages.

If you're getting the HTTP status code 417 see Handling HTTP code 417: Expectation failed

URL

The URLs are specifies the resource or resource collection. Objects are organized in a tree collection, starting with customers at the top, then domains, then domain objects next (such as mailboxes, contacts, and distribution lists) and so on. The URLs of the resources and collections accessible are found on the operation pages.

HTTP Method

It is the HTTP method that specifies what operation will be done on the resource. For example, to get the details of a mailbox a HTTP GET will be done on /customers/12345678/domains/example.com/ex/mailboxes/john.smith. If the mailbox does not exist, a HTTP POST to the same URL with the necessary form data will add the mailbox. Then, a HTTP PUT to the same URL will edit mailbox. And to delete the mailbox, an HTTP DELETE would be used.

The types of operations a certain method performs is outlined below.

HTTP Headers

All requests to the API must then include HTTP headers with the following information:

Form Data

When using Add and Edit operations, the details of the resource are sent to the API server via HTTP form data. Your HTTP library should include methods for sending form data along with an HTTP request. The library should by default send the data in the HTTP request body using the 'application/x-www-form-urlencoded' data format.

Index Filter/Search

The results of Index actions can be filtered/searched. The index URLs can take either one of the query strings: "?startswith=xx" or "?contains=xx," where "xx" is the key word. If the request specifies more than one of these two query strings, a 400 HTTP error will be returned. Different fields will be searched depending on the resource type, see below.

Note that "0-9" is a reserved key word for query string "startswith." It represents any result starting with numbers.

Throttling

The server limits the number of requests allowed per user in a certain period of time. The number of requests made are logged per minute. Calls that were made correctly with a user's API key, but not completed for any reason, including those exceeding the throttle limit, are included in this count.

If a user is over the throttling limit then a 403 HTTP code will be returned with an "Exceeded request limits" message.

Examples

Index of Exchange Mailboxes:

Hypertext Transfer Protocol
    GET /v0/customers/12345678/domains/example.com/ex/mailboxes?size=100&offset=100 HTTP/1.1
    Host: api.emailsrvr.com
    User-Agent: Rackspace Management Interface
    X-Api-Signature: eGbq9/2hcZsRlr1JV1Pi:20010317143725:HKUn0aajpSDx7qqGK3vqzn3FglI=
    Accept: text/xml

Adding New Exchange Mailbox:

Hypertext Transfer Protocol
    POST /v0/customers/12345678/domains/example.com/ex/mailboxes/john.smith HTTP/1.1
    Host: api.emailsrvr.com
    User-Agent: Rackspace Management Interface
    X-Api-Signature: eGbq9/2hcZsRlr1JV1Pi:20010317143725:HKUn0aajpSDx7qqGK3vqzn3FglI=
    Content-Length: 53
        [Content length: 53]
    Content-Type: application/x-www-form-urlencoded
 
Line-based text data: application/x-www-form-urlencoded
    size=2048&displayName=John%20Smith&password=abcABC123

Responses

HTTP Status Code

On a successfully executed request, a 200 HTTP Code is returned. If the request was unsuccessful however, an HTTP error code in the 400s or 500s will be returned.

HTTP Response Body

If the request is an Index or Show request, the request data will be returned in the format specified in the HTTP Body.

Formats

Requests for data (index and show requests) are returned with XML or JSON data based on what your application populates the HTTP Accept headers with.

For XML, populate the header with 'text/xml' (ex: Headers!["Accept"] = "text/xml"). The XML document returned will conform to a published XSD (XML Schema Document). There are many ways to parse the data in an XML document, but we have found that the XPath tree-style traversal has served our purposes. In any case, your application will likely need to use a class library for your chosen method.

For JSON, populate the header with 'application/json' (ex: Headers!["Accept"] = "application/json"). As with XML, a library will likely be needed to parse the data.

HTTP Headers

The only data returned in the header is the error message (if any).

Errors

In the event of an error, the error message will be returned the HTTP header x-error-message and an HTTP Status Code in the 400s or 500s will be returned.

Note: Every language's HTTP library provides methods for retrieving HTTP response codes and response headers.

Below are some errors that are common to many operations. Each operation also has some specific errors which are outlined with the operation.

Paging

The results of Index actions are split into pages to lessen potentially high resource usage. The index URLs have a query string with parameters in the format "?size=xx&offset=xx." If a query parameter is omitted, the default value is used.

Example

A PHP Example of paging can be found here.

Examples

HTTP/1.1 200 OK
Cache-Control: private
Content-Type: text/xml; charset=utf-8
Server: Microsoft-IIS/7.0
Date: Fri, 04 Dec 2009 19:08:11 GMT
Content-Length: 430

<?xml version="1.0" encoding="utf-8"?>
<domainList xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="urn:xml:domainList">
  <offset>0</offset>
  <size>50</size>
  <total>1</total>
  <domains>
    <domain>
      <name>customer.com</name>
      <accountNumber>123456</accountNumber>
      <serviceType>rsemail</serviceType>
    </domain>
  </domains>
</domainList>

HTTP/1.1 404 Not Found
Cache-Control: private
Server: Microsoft-IIS/7.0
x-error-message: Customer Not Found
Date: Fri, 04 Dec 2009 19:13:59 GMT
Content-Length: 0

HTTP/1.1 400 Bad Request
Cache-Control: private
Server: Microsoft-IIS/7.0
x-error-message: Missing required field: type
Date: Fri, 04 Dec 2009 19:17:29 GMT
Content-Length: 0

Examples

Ruby

This examples is written in Ruby. To make the examples shorter, helper methods have been written. These methods are part of a NetMethods module. The contents of the NetMethods module is listed below.

require  'server.rb'

server = Server.new

response = server.get  '/customers', server.xml_format

#fields = Hash['serviceType' =>  'exchange', 'exchangeMaxNumMailboxes' => '4']
#response =  server.post '/customers/me/domains/newdomain.com', fields

puts response.code
puts response['x-error-message']
puts response.body

require 'test/unit/assertions'
require 'net/http'
require 'date'
require 'date/format'
require 'digest/sha1'
require 'base64'
require 'time'

class Server
  include Test::Unit::Assertions
  
  def initialize(server='api.emailsrvr.com', version_prefix='/v0', user_key='xxxxxxxxxxxxxxxxxxxx', secret_hash='xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx')
    @server = server
    @version_prefix = version_prefix
    @user_key = user_key
    @secret_hash = secret_hash
  end
  
# Response Type Enums

  def xml_format
    'text/xml'
  end
  
  def json_format
    'application/json'
  end

#
# HTTP Request Verbs
#  
  def get(url_string, format)
    uri = full_uri(url_string)
    headers = prepared_headers
    headers['Accept'] = format
    request = Net::HTTP::Get.new(request_uri(uri), headers)
    http_response = make_request request, uri
  end
  
  def delete(url_string)
    uri = full_uri(url_string)
    request = Net::HTTP::Delete.new(request_uri(uri), prepared_headers)
    http_response = make_request request, uri
  end
  
  def put(url_string, fields_hash)
    uri = full_uri(url_string)
    request = Net::HTTP::Put.new(request_uri(uri), prepared_headers)
    request.set_form_data(fields_hash)
    http_response = make_request request, uri
  end
  
  def post(url_string, fields_hash)
    uri = full_uri(url_string)
    request = Net::HTTP::Post.new(request_uri(uri), prepared_headers)
    request.set_form_data(fields_hash)
    http_response = make_request request, uri
  end
  
#
# HTTP Request Helpers
# 
  def make_request request, uri
    response = Net::HTTP::start(uri.host, uri.port)  do |http|
      http.request request
    end
    
    response
  end
  
  def full_uri url_string
    URI.parse('http://' + @server + @version_prefix + url_string)
  end
  
  def request_uri uri
    request = uri.path
    if ! uri.query.nil?
      request = request + '?' + uri.query
    end
    request
  end
  
  def prepared_headers
    headers = Hash.new
    headers.merge! headers_auth_creds(@user_key, @secret_hash)
    headers['Accept'] = xml_format
    headers
  end
  
  def headers_auth_creds apiKey, secretKey
    userAgent = 'Ruby Test Client'
    timestamp = DateTime.now.strftime('%Y%m%d%H%M%S')
    
    data_to_sign = apiKey + userAgent + timestamp + secretKey
    
    hash = Base64.encode64(Digest::SHA1.digest(data_to_sign))
    signature = apiKey + ":" + timestamp + ":" + hash
    
    headers = Hash['User-Agent' => userAgent, 'X-Api-Signature' => signature]
  end
end

C#

This examples is written in C#.

using System;
using System.Collections.Specialized;
using System.Security.Cryptography;
using System.Text;
using System.Net;

public class WebMethods
{
  private WebClientBase client;
  private string baseUrl;
  private string apiKey;
  private string secretKey;

  public WebMethods(WebClientBase client, string baseUrl, string apiKey, string secretKey)
  {
    this.client = client;
    this.baseUrl = baseUrl;
    this.apiKey = apiKey;
    this.secretKey = secretKey;
  }

  public virtual string Get(string url)
  {
    return MakeRemoteCall((client) =>
      {
        return client.DownloadString(baseUrl + url);
      },
      format);
  }

  public virtual string Post(string url, NameValueCollection data)
  {
    return MakeRemoteCall((client) =>
      {
        var bytes = client.UploadValues(baseUrl + url, data);
        return Encoding.UTF8.GetString(bytes);
      },
      format);
  }

  private void SignMessage()
  {
    var userAgent = "C# Client Library";
    client.Headers["User-Agent"] = userAgent;

    var dateTime = DateTime.UtcNow.ToString("yyyyMMddHHmmss");

    var dataToSign = apiKey + userAgent + dateTime + secretKey;
    var hash = SHA1.Create();
    var signedBytes = hash.ComputeHash(Encoding.UTF8.GetBytes(dataToSign));
    var signature = Convert.ToBase64String(signedBytes);

    client.Headers["X-Api-Signature"] = apiKey + ":" + dateTime + ":" + signature;
  }

  private void AssignFormat(string format)
  {
    client.Headers["Accept"] = format;
  }

  private string MakeRemoteCall(Func<WebClientBase, string> remoteCall, string format)
  {
    try
    {
      SignMessage();
      AssignFormat(format);
      return remoteCall.Invoke(client);
    }
    catch (WebException e)
    {
      throw new ApiException(e);
    }
  }
}

PHP

The PHP Example can be found here.