Sending API requests to Rackspace Autoscale#

This Getting Started Guide shows how to send requests by using cURL.

Note

You can also use Rackspace Cloud API services by using the following methods:

If you are developing applications or automation, see OpenStack client applications.
For API development, testing and workflow management in a graphical environment, try interacting with the API by using an application such as Postman or RESTClient for Firefox.

cURL is a command-line tool that you can use to interact with REST interfaces. cURL lets you transmit and receive HTTP requests and responses from the command line or a shell script, which enables you to work with the API directly. cURL is available for Linux distributions, Mac OS® X, and Microsoft Windows®. For information about cURL, see http://curl.haxx.se/.

To run the cURL request examples shown in this guide, copy each example from the HTML version of this guide directly to the command line or a script.

Important

The cURL examples in this guide are provided for reference only. Because the use of cURL has environmental dependencies, copying and pasting the examples might not work in your environment.

The following example shows a cURL command for sending an authentication request to the Identity service.

cURL command example: JSON request

$ curl https://identity.api.rackspacecloud.com/v2.0/tokens  \
 -X POST \
 -d '{"auth":{"RAX-KSKEY:apiKeyCredentials":{"username":"yourUserName","apiKey":"$apiKey"}}}' \
 -H "Content-type: application/json" \
 | python -m json.tool

In this example, $apiKey is an environment variable that stores your API key value. Environment variables make it easier to reference account information in API requests, to reuse the same cURL commands with different credentials, and also to keep sensitive information like your API key from being exposed when you send requests to Rackspace Cloud API services. For details about creating environment variables, see Configure environment variables.

Note

The carriage returns in the cURL request examples use a backslash (\) as an escape character. The escape character allows continuation of the command across multiple lines.

The cURL examples in this guide use the following command-line options.

Option	Description
-d	Sends the specified data in a POST request to the HTTP server. Use this option to send a JSON request body to the server.
-H	Specifies an extra HTTP header in the request. You can specify any number of extra headers. Precede each header with the `-H` option. Common headers in Rackspace API requests are as follows: `Content-Type`: Required for operations with a request body. Specifies the format of the request body. Following is the syntax for the header where format is `json`: Content-Type: application/json `X-Auth-Token`: Required. Specifies the authentication token. `X-Auth-Project-Id`: Optional. Specifies the project ID, which can be your account number or another value. `Accept`: Optional. Specifies the format of the response body. Following is the syntax for the header where the format is `json`, which is the default: Accept: application/json
-i	Includes the HTTP header in the output.
-s	Specifies silent or quiet mode, which makes cURL mute. No progress or error messages are shown.
-T	Transfers the specified local file to the remote URL.
-X	Specifies the request method to use when communicating with the HTTP server. The specified request is used instead of the default method, which is GET.

For commands that return a response, use json.tool to pretty-print the output by appending the following command to the cURL call:

| python -m json.tool

Note

To use json.tool, import the JSON module. For information about json.tool, see JSON encoder and decoder.

If you run a Python version earlier than 2.6, import the simplejson module and use simplejson.tool. For information about simplejson.tool, see simplejson encoder and decoder.

If you do not want to pretty-print JSON output, omit this code.