fess

Fess is very powerful and easily deployable Enterprise Search Server.

Fess is a very powerful and easily deployable Enterprise Search Server. You can quickly install and run Fess on any platform where you can run the Java Runtime Environment. Fess is provided under the Apache License 2.0.

Fess is based on Elasticsearch, but knowledge/experience about Elasticsearch is not required. Fess provides an easy to use Administration GUI to configure the system via your browser. Fess also contains a Crawler, which can crawl documents on a web server, file system, or Data Store (such as a CSV or database). Many file formats are supported including (but not limited to): Microsoft Office, PDF, and zip.

Fess Site Search is a free alternative to Google Site Search. For more details, see the FSS JS Generator documentation.