From 3ec21291e84979079937f37d947ead5cb125bf4f Mon Sep 17 00:00:00 2001
From: Engin Diri <engin.diri@mail.schwarz>
Date: Thu, 7 Apr 2022 00:49:55 +0200
Subject: [PATCH] feat: add prometheus install

Signed-off-by: Engin Diri <engin.diri@mail.schwarz>
---
 cmd/system/install.go    |   1 +
 cmd/system/prometheus.go | 113 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 114 insertions(+)
 create mode 100644 cmd/system/prometheus.go

diff --git a/cmd/system/install.go b/cmd/system/install.go
index 32a760b1c..670714194 100644
--- a/cmd/system/install.go
+++ b/cmd/system/install.go
@@ -23,6 +23,7 @@ func MakeInstall() *cobra.Command {
 
 	command.AddCommand(MakeInstallGo())
 	command.AddCommand(MakeInstallFirecracker())
+	command.AddCommand(MakeInstallPrometheus())
 
 	return command
 }
diff --git a/cmd/system/prometheus.go b/cmd/system/prometheus.go
new file mode 100644
index 000000000..2fd8e8dc2
--- /dev/null
+++ b/cmd/system/prometheus.go
@@ -0,0 +1,113 @@
+package system
+
+import (
+	"fmt"
+	"github.com/alexellis/arkade/pkg/archive"
+	"github.com/alexellis/arkade/pkg/env"
+	"github.com/alexellis/arkade/pkg/get"
+	"github.com/spf13/cobra"
+	"os"
+	"strings"
+)
+
+const (
+	prometheus            = "prometheus"
+	promtool              = "promtool"
+	pathFlag              = "path"
+	versionFlag           = "version"
+	progressFlag          = "progress"
+	prometheusArchive     = "prometheus-%s.linux-%s.tar.gz"
+	githubDownloadBaseURL = "https://github.com/%s/%s/releases/download/%s/%s"
+)
+
+func MakeInstallPrometheus() *cobra.Command {
+	command := &cobra.Command{
+		Use:   prometheus,
+		Short: "Install Prometheus",
+		Long:  `Install the Prometheus monitoring system and time series database.`,
+		Example: `  arkade system install prometheus
+  arkade system install prometheus --version v2.34.0`,
+		SilenceUsage: true,
+	}
+
+	command.Flags().StringP(versionFlag, "v", "latest", "The version for Prometheus to install")
+	command.Flags().StringP(pathFlag, "p", "/usr/local/bin", "Installation path, where a go subfolder will be created")
+	command.Flags().Bool(progressFlag, true, "Show download progress")
+
+	command.RunE = func(cmd *cobra.Command, args []string) error {
+		installPath, _ := cmd.Flags().GetString(pathFlag)
+		version, _ := cmd.Flags().GetString(versionFlag)
+		progress, _ := cmd.Flags().GetBool(progressFlag)
+
+		fmt.Printf("Installing Prometheus to %s\n", installPath)
+
+		if err := os.MkdirAll(installPath, 0755); err != nil && !os.IsExist(err) {
+			fmt.Printf("Error creating directory %s, error: %s\n", installPath, err.Error())
+		}
+
+		arch, osVer := env.GetClientArch()
+
+		if strings.ToLower(osVer) != "linux" {
+			return fmt.Errorf("this app only supports Linux")
+		}
+
+		dlArch := arch
+		if arch == "x86_64" {
+			dlArch = "amd64"
+		} else if arch == "aarch64" {
+			dlArch = "arm64"
+		}
+
+		if version == "latest" {
+			v, err := get.FindGitHubRelease(prometheus, prometheus)
+			if err != nil {
+				return err
+			}
+			version = v
+		} else if !strings.HasPrefix(version, "v") {
+			version = "v" + version
+		}
+
+		fmt.Printf("Installing version: %s for: %s\n", version, dlArch)
+		filename := fmt.Sprintf(prometheusArchive, strings.TrimPrefix(version, "v"), dlArch)
+		dlURL := fmt.Sprintf(githubDownloadBaseURL, prometheus, prometheus, version, filename)
+
+		fmt.Printf("Downloading from: %s\n", dlURL)
+		outPath, err := get.DownloadFileP(dlURL, progress)
+		if err != nil {
+			return err
+		}
+		fmt.Printf("Downloaded to: %s\n", outPath)
+
+		f, err := os.OpenFile(outPath, os.O_RDONLY, 0644)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+
+		tempUnpackPath, err := os.MkdirTemp(os.TempDir(), fmt.Sprintf("%s*", prometheus))
+		if err != nil {
+			return err
+		}
+		defer os.RemoveAll(tempUnpackPath)
+		fmt.Printf("Unpacking binaries to: %s\n", tempUnpackPath)
+		if err := archive.Untar(f, tempUnpackPath, true); err != nil {
+			return err
+		}
+
+		fmt.Printf("Copying binaries to: %s\n", installPath)
+		filesToCopy := map[string]string{
+			fmt.Sprintf("%s/%s", tempUnpackPath, prometheus): fmt.Sprintf("%s/%s", installPath, prometheus),
+			fmt.Sprintf("%s/%s", tempUnpackPath, promtool):   fmt.Sprintf("%s/%s", installPath, promtool),
+		}
+		for src, dst := range filesToCopy {
+			if _, copyErr := get.CopyFile(src, dst); copyErr != nil {
+				return err
+			}
+		}
+
+		return nil
+	}
+
+	return command
+}