Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tools/custom_builder/main.go

@@ -0,0 +1,178 @@
+package main
+
+import (
+	"bytes"
+	"errors"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+var buildTargets = []string{"build"}
+
+var categories = []string{
+	"aggregators",
+	"inputs",
+	"outputs",
+	"parsers",
+	"processors",
+	"secretstores",
+	"serializers",
+}
+
+const description = `
+This is a tool build Telegraf with a custom set of plugins. The plugins are
+select according to the specified Telegraf configuration files. This allows
+to shrink the binary size by only selecting the plugins you really need.
+A more detailed documentation is available at
+http://github.com/influxdata/telegraf/tools/custom_builder/README.md
+`
+
+const examples = `
+The following command with customize Telegraf to fit the configuration found
+at the default locations
+
+  custom_builder --config /etc/telegraf/telegraf.conf --config-dir /etc/telegraf/telegraf.d
+
+You can the --config and --config-dir multiple times
+
+  custom_builder --config global.conf --config myinputs.conf --config myoutputs.conf
+
+or use one or more remote address(es) to load the config
+
+  custom_builder --config global.conf --config http://myserver/plugins.conf
+
+Combinations of local and remote config as well as config directories are
+possible.
+`
+
+func usage() {
+	fmt.Fprint(flag.CommandLine.Output(), description)
+	fmt.Fprintln(flag.CommandLine.Output(), "")
+	fmt.Fprintln(flag.CommandLine.Output(), "Usage:")
+	fmt.Fprintln(flag.CommandLine.Output(), "  custom_builder [flags]")
+	fmt.Fprintln(flag.CommandLine.Output(), "")
+	fmt.Fprintln(flag.CommandLine.Output(), "Flags:")
+	flag.PrintDefaults()
+	fmt.Fprintln(flag.CommandLine.Output(), "")
+	fmt.Fprintln(flag.CommandLine.Output(), "Examples:")
+	fmt.Fprint(flag.CommandLine.Output(), examples)
+	fmt.Fprintln(flag.CommandLine.Output(), "")
+}
+
+type cmdConfig struct {
+	dryrun      bool
+	showtags    bool
+	migrations  bool
+	quiet       bool
+	root        string
+	configFiles []string
+	configDirs  []string
+}
+
+func main() {
+	var cfg cmdConfig
+	flag.Func("config",
+		"Import plugins from configuration file (can be used multiple times)",
+		func(s string) error {
+			cfg.configFiles = append(cfg.configFiles, s)
+			return nil
+		},
+	)
+	flag.Func("config-dir",
+		"Import plugins from configs in the given directory (can be used multiple times)",
+		func(s string) error {
+			cfg.configDirs = append(cfg.configDirs, s)
+			return nil
+		},
+	)
+	flag.BoolVar(&cfg.dryrun, "dry-run", false, "Skip the actual building step")
+	flag.BoolVar(&cfg.quiet, "quiet", false, "Print fewer log messages")
+	flag.BoolVar(&cfg.migrations, "migrations", false, "Include configuration migrations")
+	flag.BoolVar(&cfg.showtags, "tags", false, "Show build-tags used")
+
+	flag.Usage = usage
+	flag.Parse()
+
+	tagset, err := process(&cfg)
+	if err != nil {
+		log.Fatalln(err)
+	}
+	if len(tagset) == 0 {
+		log.Fatalln("Nothing selected!")
+	}
+	tags := "custom,"
+	if cfg.migrations {
+		tags += "migrations,"
+	}
+	tags += strings.Join(tagset, ",")
+	if cfg.showtags {
+		fmt.Printf("Build tags: %s\n", tags)
+	}
+
+	if !cfg.dryrun {
+		// Perform the build
+		var out bytes.Buffer
+		makeCmd := exec.Command("make", buildTargets...)
+		makeCmd.Env = append(os.Environ(), "BUILDTAGS="+tags)
+		makeCmd.Stdout = &out
+		makeCmd.Stderr = &out
+
+		if !cfg.quiet {
+			log.Println("Running build...")
+		}
+		if err := makeCmd.Run(); err != nil {
+			fmt.Println(out.String())
+			log.Fatalf("Running make failed: %v", err)
+		}
+		if !cfg.quiet {
+			fmt.Println(out.String())
+		}
+	} else if !cfg.quiet {
+		log.Println("DRY-RUN: Skipping build.")
+	}
+}
+
+func process(cmdcfg *cmdConfig) ([]string, error) {
+	// Check configuration options
+	if len(cmdcfg.configFiles) == 0 && len(cmdcfg.configDirs) == 0 {
+		return nil, errors.New("no configuration specified")
+	}
+
+	// Collect all available plugins
+	packages := packageCollection{root: cmdcfg.root}
+	if err := packages.CollectAvailable(); err != nil {
+		return nil, fmt.Errorf("collecting plugins failed: %w", err)
+	}
+
+	// Import the plugin list from Telegraf configuration files
+	log.Println("Importing configuration file(s)...")
+	cfg, nfiles, err := ImportConfigurations(cmdcfg.configFiles, cmdcfg.configDirs)
+	if err != nil {
+		return nil, fmt.Errorf("importing configuration(s) failed: %w", err)
+	}
+	if !cmdcfg.quiet {
+		log.Printf("Found %d configuration files...", nfiles)
+	}
+
+	// Check if we do have a config
+	if nfiles == 0 {
+		return nil, errors.New("no configuration files loaded")
+	}
+
+	// Process the plugin list with the given config. This will
+	// only keep the plugins that adhere to the filtering criteria.
+	enabled, err := cfg.Filter(packages)
+	if err != nil {
+		return nil, fmt.Errorf("filtering packages failed: %w", err)
+	}
+	if !cmdcfg.quiet {
+		enabled.Print()
+	}
+
+	// Extract the build-tags
+	return enabled.ExtractTags(), nil
+}