Pull schemes directly from GitHub for CI (#19)

entrypoint.sh

@@ -4,6 +4,8 @@ ARGS=""
 
 if [[ -n $INPUT_PATH ]]; then
   ARGS+="-schemes-dir $INPUT_PATH"
+else
+  ARGS+="-online"
 fi
 
 /bin/base16-builder-go $ARGS

go.mod

@@ -4,14 +4,14 @@ go 1.18
 
 require (
 	github.com/cbroglie/mustache v1.3.1
+	github.com/nlepage/go-tarfs v1.1.0
 	github.com/sirupsen/logrus v1.8.1
 	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
 	github.com/kr/text v0.2.0 // indirect
 	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
-	github.com/stretchr/testify v1.7.1 // indirect
 	golang.org/x/sys v0.0.0-20220615213510-4f61da869c0c // indirect
 	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 )

go.sum

@@ -10,6 +10,8 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e h1:fD57ERR4JtEqsWbfPhv4DMiApHyliiK5xCTNVSPiaAs=
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
+github.com/nlepage/go-tarfs v1.1.0 h1:bsACOiZMB/zFjYG/sE01070i9Fl26MnRpw0L6WuyfVs=
+github.com/nlepage/go-tarfs v1.1.0/go.mod h1:IhxRcLhLkawBetnwu/JNuoPkq/6cclAllhgEa6SmzS8=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sirupsen/logrus v1.8.1 h1:dJKuHgqk1NNQlqoA6BTlM1Wf9DOH3NBjQyu0h9+AZZE=

main.go

@@ -1,11 +1,14 @@
 package main
 
 import (
+	"compress/gzip"
 	"embed"
 	"flag"
 	"io/fs"
+	"net/http"
 	"os"
 
+	"github.com/nlepage/go-tarfs"
 	"github.com/sirupsen/logrus"
 )
 
@@ -15,6 +18,7 @@ var schemesFS embed.FS
 var (
 	schemesDir  string
 	templateDir string
+	onlineMode  bool
 
 	// Define the logger we'll be using
 	logVerbose bool
@@ -31,14 +35,40 @@ func init() {
 	flag.StringVar(&schemesDir, "schemes-dir", "-", "Target directory for scheme data. The default value uses internal schemes.")
 	flag.StringVar(&templateDir, "template-dir", ".", "Target template directory to build.")
 	flag.BoolVar(&logVerbose, "verbose", false, "Log all debug messages")
+	flag.BoolVar(&onlineMode, "online", false, "Run in online mode and pull schemes directly from GitHub")
 
 	rawLog.Level = logrus.InfoLevel
 	if logVerbose {
 		rawLog.Level = logrus.DebugLevel
 	}
 }
 
+func getSchemesFromGithub() (fs.FS, error) {
+	log.Info("Attempting to load schemes from GitHub")
+
+	r, err := http.Get("https://github.com/base16-project/base16-schemes/archive/refs/heads/main.tar.gz")
+	if err != nil {
+		return nil, err
+	}
+
+	gzipReader, err := gzip.NewReader(r.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	targetFS, err := tarfs.New(gzipReader)
+	if err != nil {
+		return nil, err
+	}
+
+	// The archive has a subfolder containing all the schemes, so we return a
+	// subfs of the folder.
+	return fs.Sub(targetFS, "base16-schemes-main")
+}
+
 func main() {
+	var err error
+
 	flag.Parse()
 
 	log.WithFields(logrus.Fields{
@@ -49,8 +79,17 @@ func main() {
 
 	var targetFS fs.FS
 	if schemesDir == "-" {
-		log.Info("Using internal schemes")
-		targetFS, _ = fs.Sub(schemesFS, "schemes")
+		// If we're in online mode, the default is to pull from GitHub,
+		// otherwise use the embedded schemes.
+		if onlineMode {
+			targetFS, err = getSchemesFromGithub()
+			if err != nil {
+				log.WithError(err).Fatal("Failed to load schemes from GitHub")
+			}
+		} else {
+			log.Info("Using internal schemes")
+			targetFS, _ = fs.Sub(schemesFS, "schemes")
+		}
 	} else {
 		log.Infof("Processing scheme dir %q", schemesDir)
 		targetFS = os.DirFS(schemesDir)