Search Protocol Reference
The Google Search Appliance uses a simple HTTP-based protocol for serving search results. This enables you to control how search results are requested and how they are presented to end users. This guide describes the technical details of search requests and results. This guide assumes that you have a basic understanding of the HTTP protocol and the HTML document format.
For terminology definitions, see the Google Cloud Glossary.
The Google Search Appliance accepts search requests as input, and returns search results as output.
Search requests, the input, are simple HTTP requests to the Google Search Appliance. Search users typically use HTML forms displayed in a web browser to make these requests, but other applications can also send search requests by making appropriate HTTP requests. For information on the search request format and options, see Request Format.
Search results, the output, are returned in either HTML or XML formats, as specified in the search request.
HTML-formatted results can be displayed directly in a web browser. The search appliance generates HTML results by applying an XSL stylesheet to the XML results. You can customize the appearance of the HTML results by modifying this stylesheet. For more information, see Custom HTML.
XML-formatted output makes it possible to process the search results in web applications or other environments. For information on the XML results format, see XML Output.