What is it?

licenses uses go list tool over a Go workspace to collect the dependencies of a package or command, detect their license if any and match them against well-known templates. You must run this from within the root module folder.

[module github.com/blevesearch/bleve]
$ licenses ./...
github.com/blevesearch/bleve             Apache License 2.0
github.com/blevesearch/go-porterstemmer  MIT License (93%)
github.com/blevesearch/segment           Apache License 2.0
github.com/boltdb/bolt                   MIT License (97%)
github.com/golang/protobuf/proto         BSD 3-clause "New" or "Revised" License (91%)
github.com/steveyen/gtreap               MIT License (96%)
vendor/golang.org/x/net/http2/hpack      ?

Unmatched license words can be displayed with:

$ licenses -w ./...
github.com/steveyen/gtreap  MIT License (98%)
                            -words: mit, license

Where does it come from?

Both the code and reference data were directly ported from:

https://github.com/benbalter/licensee