Fix #135

internal/version/github.go

@@ -0,0 +1,58 @@
+package version
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"net/http"
+	"time"
+)
+
+type githubRelease struct {
+	TagName     string    `json:"tag_name"`
+	Name        string    `json:"name"`
+	Prerelease  bool      `json:"prerelease"`
+	PublishedAt time.Time `json:"published_at"`
+}
+
+type githubCommit struct {
+	Sha    string `json:"sha"`
+	Commit struct {
+		Committer struct {
+			Date time.Time `json:"date"`
+		} `json:"committer"`
+	}
+}
+
+func getGithubReleases(client *http.Client) (releases []githubRelease, err error) {
+	const url = "https://api.github.com/repos/qdm12/gluetun/releases"
+	response, err := client.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer response.Body.Close()
+	b, err := ioutil.ReadAll(response.Body)
+	if err != nil {
+		return nil, err
+	}
+	if err := json.Unmarshal(b, &releases); err != nil {
+		return nil, err
+	}
+	return releases, nil
+}
+
+func getGithubCommits(client *http.Client) (commits []githubCommit, err error) {
+	const url = "https://api.github.com/repos/qdm12/gluetun/commits"
+	response, err := client.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer response.Body.Close()
+	b, err := ioutil.ReadAll(response.Body)
+	if err != nil {
+		return nil, err
+	}
+	if err := json.Unmarshal(b, &commits); err != nil {
+		return nil, err
+	}
+	return commits, nil
+}

internal/version/version.go

@@ -0,0 +1,88 @@
+package version
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+)
+
+// GetMessage returns a message for the user describing if there is a newer version
+// available. It should only be called once the tunnel is established.
+func GetMessage(version, commitShort string, client *http.Client) (message string, err error) {
+	if version == "latest" {
+		// Find # of commits between current commit and latest commit
+		commitsSince, err := getCommitsSince(client, commitShort)
+		if err != nil {
+			return "", fmt.Errorf("cannot get version information: %w", err)
+		} else if commitsSince == 0 {
+			return fmt.Sprintf("You are running on the bleeding edge of %s!", version), nil
+		}
+		commits := "commits"
+		if commitsSince == 1 {
+			commits = "commit"
+		}
+		return fmt.Sprintf("You are running %d %s behind the most recent %s", commitsSince, commits, version), nil
+	}
+	tagName, name, releaseTime, err := getLatestRelease(client)
+	if err != nil {
+		return "", fmt.Errorf("cannot get version information: %w", err)
+	}
+	if tagName == version {
+		return fmt.Sprintf("You are running the latest release %s", version), nil
+	}
+	timeSinceRelease := formatDuration(time.Since(releaseTime))
+	return fmt.Sprintf("There is a new release %s (%s) created %s ago",
+			tagName, name, timeSinceRelease),
+		nil
+}
+
+func formatDuration(duration time.Duration) string {
+	switch {
+	case duration < time.Minute:
+		seconds := int(duration.Round(time.Second).Seconds())
+		if seconds < 2 {
+			return fmt.Sprintf("%d second", seconds)
+		}
+		return fmt.Sprintf("%d seconds", seconds)
+	case duration <= time.Hour:
+		minutes := int(duration.Round(time.Minute).Minutes())
+		if minutes == 1 {
+			return "1 minute"
+		}
+		return fmt.Sprintf("%d minutes", minutes)
+	case duration < 48*time.Hour:
+		hours := int(duration.Truncate(time.Hour).Hours())
+		return fmt.Sprintf("%d hours", hours)
+	default:
+		days := int(duration.Truncate(time.Hour).Hours() / 24)
+		return fmt.Sprintf("%d days", days)
+	}
+}
+
+func getLatestRelease(client *http.Client) (tagName, name string, time time.Time, err error) {
+	releases, err := getGithubReleases(client)
+	if err != nil {
+		return "", "", time, err
+	}
+	for _, release := range releases {
+		if release.Prerelease {
+			continue
+		}
+		return release.TagName, release.Name, release.PublishedAt, nil
+	}
+	return "", "", time, fmt.Errorf("no releases found")
+}
+
+func getCommitsSince(client *http.Client, commitShort string) (n int, err error) {
+	commits, err := getGithubCommits(client)
+	if err != nil {
+		return 0, err
+	}
+	for i := range commits {
+		if commits[i].Sha[:7] == commitShort {
+			return n, nil
+		}
+		n++
+	}
+	return 0, fmt.Errorf("no commit matching %q was found", commitShort)
+}

internal/version/version_test.go

@@ -0,0 +1,64 @@
+package version
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_formatDuration(t *testing.T) {
+	t.Parallel()
+	testCases := map[string]struct {
+		duration time.Duration
+		s        string
+	}{
+		"zero": {
+			s: "0 second",
+		},
+		"one second": {
+			duration: time.Second,
+			s:        "1 second",
+		},
+		"59 seconds": {
+			duration: 59 * time.Second,
+			s:        "59 seconds",
+		},
+		"1 minute": {
+			duration: time.Minute,
+			s:        "1 minute",
+		},
+		"2 minutes": {
+			duration: 2 * time.Minute,
+			s:        "2 minutes",
+		},
+		"1 hour": {
+			duration: time.Hour,
+			s:        "60 minutes",
+		},
+		"2 hours": {
+			duration: 2 * time.Hour,
+			s:        "2 hours",
+		},
+		"26 hours": {
+			duration: 26 * time.Hour,
+			s:        "26 hours",
+		},
+		"28 hours": {
+			duration: 28 * time.Hour,
+			s:        "28 hours",
+		},
+		"55 hours": {
+			duration: 55 * time.Hour,
+			s:        "2 days",
+		},
+	}
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+			s := formatDuration(testCase.duration)
+			assert.Equal(t, testCase.s, s)
+		})
+	}
+}