Add CLI interface and resolve Yarn versions (#654)

cmd/resolve-version/main.go

@@ -7,6 +7,7 @@ import (
 	"io/ioutil"
 	"net/http"
 	"net/url"
+	"os"
 	"regexp"
 	"sort"
 	"time"
@@ -47,6 +48,53 @@ type matchResult struct {
 	matched            bool
 }
 
+func main() {
+	if len(os.Args) < 3 {
+		printUsage()
+		os.Exit(0)
+	}
+	binary := os.Args[1]
+	versionRequirement := os.Args[2]
+
+	if binary == "yarn" {
+		objects, err := listS3Objects("heroku-nodebin", "yarn")
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		result, err := resolveYarn(objects, versionRequirement)
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		if result.matched {
+			fmt.Printf("%s %s\n", result.release.version.String(), result.release.url)
+		} else {
+			fmt.Println("No result")
+			os.Exit(1)
+		}
+	}
+}
+
+func printUsage() {
+	fmt.Println("resolve-version binary version-requirement")
+}
+
+func resolveYarn(objects []s3Object, versionRequirement string) (matchResult, error) {
+	releases := []release{}
+
+	for _, obj := range objects {
+		release, err := parseObject(obj.Key)
+		if err != nil {
+			continue
+		}
+
+		releases = append(releases, release)
+	}
+
+	return matchReleaseSemver(releases, versionRequirement)
+}
+
 func matchReleaseSemver(releases []release, versionRequirement string) (matchResult, error) {
 	constraints, err := semver.NewConstraint(versionRequirement)
 	if err != nil {
@@ -193,7 +241,3 @@ func listS3Objects(bucketName string, prefix string) ([]s3Object, error) {
 
 	return out, nil
 }
-
-func main() {
-	fmt.Println("hello world")
-}

cmd/resolve-version/main_test.go

 package main
 
 import (
+	"fmt"
 	"testing"
+	"time"
 
 	"github.com/Masterminds/semver"
 
@@ -122,3 +124,58 @@ func TestMatchReleaseSemver(t *testing.T) {
 	assert.False(t, result.matched)
 	assert.Equal(t, result.versionRequirement, "99.x")
 }
+
+func genYarnS3ObjectList(versions []string) []s3Object {
+	out := []s3Object{}
+	for _, version := range versions {
+		out = append(out, s3Object{
+			Key:          fmt.Sprintf("yarn/release/yarn-v%s.tar.gz", version),
+			LastModified: time.Time{},
+			ETag:         "abcdef",
+			Size:         0,
+			StorageClass: "normal",
+		})
+	}
+	return out
+}
+
+func TestResolveYarn(t *testing.T) {
+	// yarn releases as of 4/18/2019
+	objects := genYarnS3ObjectList([]string{
+		"0.16.0", "0.16.1", "0.17.0", "0.17.10", "0.17.2", "0.17.3", "0.17.4", "0.17.5", "0.17.6",
+		"0.17.7", "0.17.8", "0.17.9", "0.18.0", "0.18.1", "0.18.2", "0.19.0", "0.19.1", "0.20.0",
+		"0.20.3", "0.20.4", "0.21.0", "0.21.1", "0.21.2", "0.21.3", "0.22.0", "0.23.0", "0.23.2",
+		"0.23.3", "0.23.4", "0.24.0", "0.24.1", "0.24.2", "0.24.3", "0.24.4", "0.24.5", "0.24.6",
+		"0.25.1", "0.25.2", "0.25.3", "0.25.4", "0.26.1", "0.27.0", "0.27.1", "0.27.2", "0.27.3",
+		"0.27.4", "0.27.5", "0.28.1", "0.28.4", "1.0.0", "1.0.1", "1.0.2", "1.1.0", "1.10.0",
+		"1.10.1", "1.11.0", "1.11.1", "1.12.0", "1.12.1", "1.12.3", "1.13.0", "1.14.0", "1.15.0",
+		"1.15.1", "1.15.2", "1.2.0", "1.2.1", "1.3.2", "1.4.0", "1.5.1", "1.6.0", "1.7.0", "1.8.0",
+		"1.9.1", "1.9.2", "1.9.4",
+	})
+
+	cases := []Case{
+		Case{input: "1.13.0", output: "1.13.0"},
+		Case{input: "1.15.2", output: "1.15.2"},
+		Case{input: "1.x", output: "1.15.2"},
+		Case{input: "*", output: "1.15.2"},
+		Case{input: "^1.12.1", output: "1.15.2"},
+		Case{input: "^1.9.4", output: "1.15.2"},
+		Case{input: ">= 1.0.0", output: "1.15.2"},
+		Case{input: "^1.0", output: "1.15.2"},
+		Case{input: "0.24.6 - 1.x", output: "1.15.2"},
+		Case{input: "1.*.*", output: "1.15.2"},
+		Case{input: "^v1.0.1", output: "1.15.2"},
+		Case{input: "1.13 - 1.16", output: "1.15.2"},
+		// TODO: these fail to parse with the library
+		// Case{input: ">=1.9.4 <2.0.0", output: "1.15.2"},
+	}
+
+	for _, c := range cases {
+		result, err := resolveYarn(objects, c.input)
+		if assert.Nil(t, err) {
+			assert.True(t, result.matched)
+			assert.Equal(t, result.release.version.String(), c.output)
+			assert.Equal(t, result.release.url, fmt.Sprintf("https://s3.amazonaws.com/heroku-nodebin/yarn/release/yarn-v%s.tar.gz", c.output))
+		}
+	}
+}