fess
Open source enterprise search server for websites, files, and data
...Fess includes a built-in crawler that can collect content from sources such as databases, CSV files, and shared storage, making it suitable for centralized knowledge discovery. It supports indexing and searching across many document formats including office documents, PDFs, and compressed archives. It also provides a web-based administrative interface that allows administrators to configure crawling targets, manage indexing tasks, and adjust search settings from a graphical dashboard.