Add support for SBT

internal/buildpack/buildpack.go

@@ -52,6 +52,7 @@ var packs = map[string]func(context.Context, Sys, yb.BuildpackSpec) (biome.Envir
 	"r":          installR,
 	"ruby":       installRuby,
 	"rust":       installRust,
+	"sbt":        installSBT,
 	"yarn":       installYarn,
 }
 
@@ -101,14 +102,18 @@ func extract(ctx context.Context, sys Sys, dstDir, url string, extractMode bool)
 		zipExt    = ".zip"
 		tarXZExt  = ".tar.xz"
 		tarGZExt  = ".tar.gz"
+		tgzExt    = ".tgz"
 		tarBZ2Ext = ".tar.bz2"
+		tbz2Ext   = ".tbz2"
 	)
 	const cleanupTimeout = 10 * time.Second
 	exts := []string{
 		zipExt,
 		tarXZExt,
 		tarGZExt,
+		tgzExt,
 		tarBZ2Ext,
+		tbz2Ext,
 	}
 	var ext string
 	for _, testExt := range exts {
@@ -183,7 +188,7 @@ func extract(ctx context.Context, sys Sys, dstDir, url string, extractMode bool)
 		if extractMode == stripTopDirectory {
 			invoke.Argv = append(invoke.Argv, "--strip-components", "1")
 		}
-	case tarGZExt:
+	case tarGZExt, tgzExt:
 		invoke.Argv = []string{
 			"tar",
 			"-x", // extract
@@ -193,7 +198,7 @@ func extract(ctx context.Context, sys Sys, dstDir, url string, extractMode bool)
 		if extractMode == stripTopDirectory {
 			invoke.Argv = append(invoke.Argv, "--strip-components", "1")
 		}
-	case tarBZ2Ext:
+	case tarBZ2Ext, tbz2Ext:
 		invoke.Argv = []string{
 			"tar",
 			"-x", // extract

internal/buildpack/sbt.go

@@ -0,0 +1,111 @@
+// Copyright 2021 YourBase Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package buildpack
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"os"
+	"io/ioutil"
+
+	"github.com/yourbase/yb"
+	"github.com/yourbase/yb/internal/biome"
+	"zombiezen.com/go/log"
+)
+
+func installSBT(ctx context.Context, sys Sys, spec yb.BuildpackSpec) (_ biome.Environment, err error) {
+	installDir := sys.Biome.JoinPath(sys.Biome.Dirs().Tools, "sbt", spec.Version())
+	desc := sys.Biome.Describe()
+	parentDir := os.TempDir()
+	socketDir, err := ioutil.TempDir(parentDir, "*-ybsbt")
+	if err != nil {
+		log.Errorf(ctx, "Error creating directory for SBT sockets: %v", err)
+	}
+	log.Infof(ctx, "SBT will use %s as the socket directory", socketDir)
+//	defer os.RemoveAll(socketDir) // clean up
+
+	env := biome.Environment{
+		Vars: map[string]string{
+			"SBT_GLOBAL_SERVER_DIR": socketDir,
+		},
+		PrependPath: []string{sys.Biome.JoinPath(installDir)},
+	}
+
+	// If directory already exists, then use it.
+	if _, err := biome.EvalSymlinks(ctx, sys.Biome, installDir); err == nil {
+		log.Infof(ctx, "SBT v%s located in %s", spec.Version(), installDir)
+		return env, nil
+	}
+
+	log.Infof(ctx, "Installing SBT v%s in %s", spec.Version(), installDir)
+	downloadURL, err := sbtDownloadURL(spec.Version(), desc)
+	if err != nil {
+		return biome.Environment{}, err
+	}
+	if err := extract(ctx, sys, installDir, downloadURL, stripTopDirectory); err != nil {
+		return biome.Environment{}, err
+	}
+	return env, nil
+}
+
+func sbtDownloadURL(version string, desc *biome.Descriptor) (string, error) {
+	vparts := strings.SplitN(version, "+", 2)
+	subVersion := ""
+	if len(vparts) > 1 {
+		subVersion = vparts[1]
+		version = vparts[0]
+	}
+
+	parts := strings.Split(version, ".")
+
+	majorVersion, err := convertVersionPiece(parts, 0)
+	if err != nil {
+		return "", fmt.Errorf("parse jdk version %q: major: %w", version, err)
+	}
+	minorVersion, err := convertVersionPiece(parts, 1)
+	if err != nil {
+		return "", fmt.Errorf("parse jdk version %q: minor: %w", version, err)
+	}
+	patchVersion, err := convertVersionPiece(parts, 2)
+	if err != nil {
+		return "", fmt.Errorf("parse jdk version %q: patch: %w", version, err)
+	}
+
+	urlPattern := "https://github.com/sbt/sbt/releases/download/v{{ .MajorVersion }}.{{ .MinorVersion }}.{{ .PatchVersion }}/sbt-{{ .MajorVersion }}.{{ .MinorVersion }}.{{ .PatchVersion }}.tgz"
+
+	var data struct {
+		OS           string
+		Arch         string
+		MajorVersion int64
+		MinorVersion int64
+		PatchVersion int64
+		SubVersion   string // not always an int, sometimes a float
+	}
+	data.OS = map[string]string{
+		biome.Linux: "linux",
+		biome.MacOS: "mac",
+	}[desc.OS]
+	if data.OS == "" {
+		return "", fmt.Errorf("unsupported os %s", desc.OS)
+	}
+	data.MajorVersion = majorVersion
+	data.MinorVersion = minorVersion
+	data.PatchVersion = patchVersion
+	data.SubVersion = subVersion
+	return templateToString(urlPattern, data)
+}

internal/buildpack/sbt_test.go

@@ -0,0 +1,46 @@
+// Copyright 2021 YourBase Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package buildpack
+
+import (
+	"context"
+	"strings"
+	"testing"
+
+	"github.com/yourbase/yb/internal/biome"
+	"zombiezen.com/go/log/testlog"
+)
+
+func TestSBT(t *testing.T) {
+	const version = "1.5.2"
+	ctx := testlog.WithTB(context.Background(), t)
+	// TODO(johnewart): SBT depends on Java  -- see Ross's comment in sbt tests
+	sbtBiome, _ := testInstall(ctx, t, "java:8.252.10", "sbt:"+version)
+	versionOutput := new(strings.Builder)
+	err := sbtBiome.Run(ctx, &biome.Invocation{
+		Argv:   []string{"sbt", "--version"},
+		Stdout: versionOutput,
+		Stderr: versionOutput,
+	})
+	t.Logf("sbt --version output:\n%s", versionOutput)
+	if err != nil {
+		t.Errorf("sbt --version: %v", err)
+	}
+	if got := versionOutput.String(); !strings.Contains(got, version) {
+		t.Errorf("sbt --version output does not include %q", version)
+	}
+}