os_release.go: Added support end parsing support. (#2982)

* os_release.go: Added support end parsing support.

Fixes: #2977

Signed-off-by: Jonathan Davies <jpds@protonmail.com>

* os_release_test.go: Added TestParseOSSupportEnd.

Signed-off-by: Jonathan Davies <jpds@protonmail.com>

---------

Signed-off-by: Jonathan Davies <jpds@protonmail.com>

collector/os_release.go

@@ -53,6 +53,7 @@ type osRelease struct {
 	BuildID         string
 	ImageID         string
 	ImageVersion    string
+	SupportEnd      string
 }
 
 type osReleaseCollector struct {
@@ -65,6 +66,8 @@ type osReleaseCollector struct {
 	osReleaseFilenames []string // all os-release file names to check
 	version            float64
 	versionDesc        *prometheus.Desc
+	supportEnd         time.Time
+	supportEndDesc     *prometheus.Desc
 }
 
 type Plist struct {
@@ -97,6 +100,11 @@ func NewOSCollector(logger log.Logger) (Collector, error) {
 			"Metric containing the major.minor part of the OS version.",
 			[]string{"id", "id_like", "name"}, nil,
 		),
+		supportEndDesc: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, "os", "support_end_timestamp_seconds"),
+			"Metric containing the end-of-life date timestamp of the OS.",
+			nil, nil,
+		),
 	}, nil
 }
 
@@ -115,6 +123,7 @@ func parseOSRelease(r io.Reader) (*osRelease, error) {
 		BuildID:         env["BUILD_ID"],
 		ImageID:         env["IMAGE_ID"],
 		ImageVersion:    env["IMAGE_VERSION"],
+		SupportEnd:      env["SUPPORT_END"],
 	}, err
 }
 
@@ -169,6 +178,15 @@ func (c *osReleaseCollector) UpdateStruct(path string) error {
 	} else {
 		c.version = 0
 	}
+
+	if c.os.SupportEnd != "" {
+		c.supportEnd, err = time.Parse("2006-01-02", c.os.SupportEnd)
+
+		if err != nil {
+			return err
+		}
+	}
+
 	return nil
 }
 
@@ -195,6 +213,11 @@ func (c *osReleaseCollector) Update(ch chan<- prometheus.Metric) error {
 		ch <- prometheus.MustNewConstMetric(c.versionDesc, prometheus.GaugeValue, c.version,
 			c.os.ID, c.os.IDLike, c.os.Name)
 	}
+
+	if c.os.SupportEnd != "" {
+		ch <- prometheus.MustNewConstMetric(c.supportEndDesc, prometheus.GaugeValue, float64(c.supportEnd.Unix()))
+	}
+
 	return nil
 }
 

collector/os_release_test.go

@@ -33,12 +33,28 @@ SUPPORT_URL="https://www.debian.org/support"
 BUG_REPORT_URL="https://bugs.debian.org/"
 `
 
+const nixosTapir string = `BUG_REPORT_URL="https://github.com/NixOS/nixpkgs/issues"
+BUILD_ID="23.11.20240328.219951b"
+DOCUMENTATION_URL="https://nixos.org/learn.html"
+HOME_URL="https://nixos.org/"
+ID=nixos
+LOGO="nix-snowflake"
+NAME=NixOS
+PRETTY_NAME="NixOS 23.11 (Tapir)"
+SUPPORT_END="2024-06-30"
+SUPPORT_URL="https://nixos.org/community.html"
+VERSION="23.11 (Tapir)"
+VERSION_CODENAME=tapir
+VERSION_ID="23.11"
+`
+
 func TestParseOSRelease(t *testing.T) {
 	want := &osRelease{
 		Name:            "Ubuntu",
 		ID:              "ubuntu",
 		IDLike:          "debian",
 		PrettyName:      "Ubuntu 20.04.2 LTS",
+		SupportEnd:      "",
 		Version:         "20.04.2 LTS (Focal Fossa)",
 		VersionID:       "20.04",
 		VersionCodename: "focal",
@@ -75,6 +91,32 @@ func TestParseOSRelease(t *testing.T) {
 	}
 }
 
+func TestParseOSSupportEnd(t *testing.T) {
+	want := &osRelease{
+		BuildID:         "23.11.20240328.219951b",
+		Name:            "NixOS",
+		ID:              "nixos",
+		IDLike:          "",
+		ImageID:         "",
+		ImageVersion:    "",
+		PrettyName:      "NixOS 23.11 (Tapir)",
+		SupportEnd:      "2024-06-30",
+		Variant:         "",
+		VariantID:       "",
+		Version:         "23.11 (Tapir)",
+		VersionID:       "23.11",
+		VersionCodename: "tapir",
+	}
+
+	got, err := parseOSRelease(strings.NewReader(nixosTapir))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(want, got) {
+		t.Fatalf("should have %+v osRelease: got %+v", want, got)
+	}
+}
+
 func TestUpdateStruct(t *testing.T) {
 	wantedOS := &osRelease{
 		Name:            "Ubuntu",