Switch to licenseclassifier/v2

This greatly improves the classifier's accuracy, and avoids having to
handle the license database in lichen (it's embedded in the
classifier).

The classifier returns "Copyright" matches, which is a behaviour
change for lichen, so these matches are ignored.

Signed-off-by: Stephen Kitt <skitt@redhat.com>

README.md

@@ -62,31 +62,33 @@ We can run lichen on itself:
 
 ```
 $ lichen $GOPATH/bin/lichen
-github.com/cpuguy83/go-md2man/v2@v2.0.0-20190314233015-f79a8a8ca69d: MIT (allowed)
-github.com/google/goterm@v0.0.0-20190703233501-fc88cf888a3f: BSD-3-Clause (allowed)
-github.com/google/licenseclassifier@v0.0.0-20200402202327-879cb1424de0: Apache-2.0 (allowed)
+github.com/cpuguy83/go-md2man/v2@v2.0.1: MIT (allowed)
+github.com/davecgh/go-spew@v1.1.1: ISC (allowed)
+github.com/google/licenseclassifier/v2@v2.0.0: Apache-2.0 (allowed)
 github.com/hashicorp/errwrap@v1.0.0: MPL-2.0 (allowed)
-github.com/hashicorp/go-multierror@v1.1.0: MPL-2.0 (allowed)
-github.com/lucasb-eyer/go-colorful@v1.0.3: MIT (allowed)
-github.com/mattn/go-isatty@v0.0.12: MIT (allowed)
-github.com/muesli/termenv@v0.5.2: MIT (allowed)
-github.com/russross/blackfriday/v2@v2.0.1: BSD-2-Clause (allowed)
-github.com/sergi/go-diff@v1.0.0: MIT (allowed)
-github.com/shurcooL/sanitized_anchor_name@v1.0.0: MIT (allowed)
-github.com/urfave/cli/v2@v2.2.0: MIT (allowed)
-golang.org/x/sys@v0.0.0-20200116001909-b77594299b42: BSD-3-Clause (allowed)
-gopkg.in/yaml.v2@v2.3.0: Apache-2.0, MIT (allowed)
+github.com/hashicorp/go-multierror@v1.1.1: MPL-2.0 (allowed)
+github.com/lucasb-eyer/go-colorful@v1.2.0: MIT (allowed)
+github.com/mattn/go-isatty@v0.0.14: MIT (allowed)
+github.com/mattn/go-runewidth@v0.0.13: MIT (allowed)
+github.com/muesli/termenv@v0.11.0: MIT (allowed)
+github.com/rivo/uniseg@v0.2.0: MIT (allowed)
+github.com/russross/blackfriday/v2@v2.1.0: BSD-2-Clause (allowed)
+github.com/sergi/go-diff@v1.1.0: MIT (allowed)
+github.com/urfave/cli/v2@v2.4.0: MIT (allowed)
+golang.org/x/sys@v0.0.0-20210630005230-0f9fa26af87c: BSD-3-Clause (allowed)
+gopkg.in/yaml.v2@v2.4.0: Apache-2.0, MIT (allowed)
 ```
 
 ...and using a custom template:
 
 ```
 $ lichen --template="{{range .Modules}}{{range .Module.Licenses}}{{.Name | printf \"%s\n\"}}{{end}}{{end}}" $GOPATH/bin/lichen | sort | uniq -c | sort -nr
-   8 MIT
-   2 MPL-2.0
-   2 BSD-3-Clause
-   2 Apache-2.0
-   1 BSD-2-Clause
+      9 MIT
+      2 MPL-2.0
+      2 Apache-2.0
+      1 ISC
+      1 BSD-3-Clause
+      1 BSD-2-Clause
 ```
 
 ## Config

go.mod

@@ -3,7 +3,7 @@ module github.com/uw-labs/lichen
 go 1.18
 
 require (
-	github.com/google/licenseclassifier v0.0.0-20201113175434-78a70215ca36
+	github.com/google/licenseclassifier/v2 v2.0.0
 	github.com/hashicorp/go-multierror v1.1.1
 	github.com/muesli/termenv v0.11.0
 	github.com/stretchr/testify v1.7.1
@@ -13,15 +13,15 @@ require (
 
 require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.1 // indirect
-	github.com/davecgh/go-spew v1.1.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/hashicorp/errwrap v1.0.0 // indirect
 	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
 	github.com/mattn/go-isatty v0.0.14 // indirect
 	github.com/mattn/go-runewidth v0.0.13 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/rivo/uniseg v0.2.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
-	github.com/sergi/go-diff v1.0.0 // indirect
+	github.com/sergi/go-diff v1.1.0 // indirect
 	golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c // indirect
 	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
 )

go.sum

@@ -1,15 +1,22 @@
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/cpuguy83/go-md2man/v2 v2.0.1 h1:r/myEWzV9lfsM1tFLgDyu0atFtJ1fXn261LKYj/3DxU=
 github.com/cpuguy83/go-md2man/v2 v2.0.1/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
-github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
-github.com/google/licenseclassifier v0.0.0-20201113175434-78a70215ca36 h1:YGB3wNLUTvq+lbIwdNRsaMJvoX4mCKkwzHlmlT1V+ow=
-github.com/google/licenseclassifier v0.0.0-20201113175434-78a70215ca36/go.mod h1:qsqn2hxC+vURpyBRygGUuinTO42MFRLcsmQ/P8v94+M=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/go-cmp v0.5.2 h1:X2ev0eStA3AbceY54o37/0PQ/UWqKEiiO2dKL5OPaFM=
+github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/licenseclassifier/v2 v2.0.0 h1:1Y57HHILNf4m0ABuMVb6xk4vAJYEUO0gDxNpog0pyeA=
+github.com/google/licenseclassifier/v2 v2.0.0/go.mod h1:cOjbdH0kyC9R22sdQbYsFkto4NGCAc+ZSwbeThazEtM=
 github.com/hashicorp/errwrap v1.0.0 h1:hLrqtEDnRye3+sgx6z4qVLNuviH3MR5aQ0ykNJa/UYA=
 github.com/hashicorp/errwrap v1.0.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
 github.com/hashicorp/go-multierror v1.1.1 h1:H5DkEtf6CXdFp0N0Em5UCwQpXMWke8IA0+lD48awMYo=
 github.com/hashicorp/go-multierror v1.1.1/go.mod h1:iw975J/qwKPdAO1clOe2L8331t/9/fmwbPZ6JB6eMoM=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
 github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
 github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
@@ -24,18 +31,23 @@ github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
-github.com/sergi/go-diff v1.0.0 h1:Kpca3qRNrduNnOQeazBd0ysaKrUJiIuISHxogkT9RPQ=
-github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
+github.com/sergi/go-diff v1.1.0 h1:we8PVUC3FE2uYfodKH/nBHMSetSfHDR6scGdBi+erh0=
+github.com/sergi/go-diff v1.1.0/go.mod h1:STckp+ISIX8hZLjrqAeVduY0gWCT9IjLuqbuNXdaHfM=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/urfave/cli/v2 v2.4.0 h1:m2pxjjDFgDxSPtO8WSdbndj17Wu2y8vOT86wE/tjr+I=
 github.com/urfave/cli/v2 v2.4.0/go.mod h1:NX9W0zmTvedE5oDoOMs2RTC8RvdK98NTYZE5LbaEYPg=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c h1:F1jZWGFhYfh0Ci55sIpILtKKK8p3i2/krTr0H1rg74I=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=

internal/license/resolve.go

@@ -1,30 +1,20 @@
 package license
 
 import (
-	"fmt"
 	"io/ioutil"
 	"path/filepath"
 	"regexp"
 	"strings"
 
-	"github.com/google/licenseclassifier"
-	"github.com/uw-labs/lichen/internal/license/db"
+	classifier "github.com/google/licenseclassifier/v2"
+	"github.com/google/licenseclassifier/v2/assets"
 	"github.com/uw-labs/lichen/internal/model"
 )
 
 // Resolve inspects each module and determines what it is licensed under. The returned slice contains each
 // module enriched with license information.
 func Resolve(modules []model.Module, threshold float64) ([]model.Module, error) {
-	archiveFn := licenseclassifier.ArchiveFunc(func() ([]byte, error) {
-		f, err := db.Open()
-		if err != nil {
-			return nil, fmt.Errorf("failed to open license databse: %w", err)
-		}
-		defer f.Close()
-		return ioutil.ReadAll(f)
-	})
-
-	lc, err := licenseclassifier.New(threshold, archiveFn)
+	lc, err := assets.DefaultClassifier()
 	if err != nil {
 		return nil, err
 	}
@@ -68,17 +58,17 @@ func locateLicenses(path string) (lp []string, err error) {
 }
 
 // classify inspects each license file and classifies it
-func classify(lc *licenseclassifier.License, paths []string) ([]model.License, error) {
+func classify(lc *classifier.Classifier, paths []string) ([]model.License, error) {
 	licenses := make([]model.License, 0)
 	for _, p := range paths {
 		content, err := ioutil.ReadFile(p)
 		if err != nil {
 			return nil, err
 		}
 		hits := make(map[string]float64)
-		matches := lc.MultipleMatch(string(content), true)
-		for _, match := range matches {
-			if conf, found := hits[match.Name]; !found || match.Confidence > conf {
+		matches := lc.Match(content)
+		for _, match := range matches.Matches {
+			if conf, found := hits[match.Name]; match.MatchType != "Copyright" && (!found || match.Confidence > conf) {
 				hits[match.Name] = match.Confidence
 			}
 		}