feat(notifications): on update available (#352)

pkg/version/version.go

@@ -0,0 +1,101 @@
+package version
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"github.com/autobrr/autobrr/pkg/errors"
+
+	goversion "github.com/hashicorp/go-version"
+)
+
+// Release is a GitHub release
+type Release struct {
+	TagName         string  `json:"tag_name,omitempty"`
+	TargetCommitish *string `json:"target_commitish,omitempty"`
+	Name            *string `json:"name,omitempty"`
+	Body            *string `json:"body,omitempty"`
+	Draft           *bool   `json:"draft,omitempty"`
+	Prerelease      *bool   `json:"prerelease,omitempty"`
+}
+
+func (r *Release) IsPreOrDraft() bool {
+	if *r.Draft || *r.Prerelease {
+		return true
+	}
+	return false
+}
+
+type Checker struct {
+	// user/repo-name or org/repo-name
+	Owner string
+	Repo  string
+}
+
+func (c *Checker) get(ctx context.Context) (*Release, error) {
+	url := fmt.Sprintf("https://api.github.com/repos/%v/%v/releases/latest", c.Owner, c.Repo)
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("Accept", "application/vnd.github.v3+json")
+	client := http.DefaultClient
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("error getting releases for %v: %s", c.Repo, resp.Status)
+	}
+
+	var release Release
+	dec := json.NewDecoder(resp.Body)
+	if err := dec.Decode(&release); err != nil {
+		return nil, err
+	}
+
+	return &release, nil
+}
+
+func (c *Checker) CheckNewVersion(ctx context.Context, version string) (bool, string, error) {
+	if version == "dev" {
+		return false, "", nil
+	}
+
+	release, err := c.get(ctx)
+	if err != nil {
+		return false, "", err
+	}
+
+	return c.checkNewVersion(version, release)
+}
+
+func (c *Checker) checkNewVersion(version string, release *Release) (bool, string, error) {
+	currentVersion, err := goversion.NewVersion(version)
+	if err != nil {
+		return false, "", errors.Wrap(err, "error parsing current version")
+	}
+
+	releaseVersion, err := goversion.NewVersion(release.TagName)
+	if err != nil {
+		return false, "", errors.Wrap(err, "error parsing release version")
+	}
+
+	if len(currentVersion.Prerelease()) == 0 && len(releaseVersion.Prerelease()) > 0 {
+		return false, "", nil
+	}
+
+	if releaseVersion.GreaterThan(currentVersion) {
+		// new update available
+		return true, releaseVersion.String(), nil
+	}
+
+	return false, "", nil
+}