CF apps running each diego cell

main.go

package main

import (
	"context"
	"fmt"
	"github.com/cloudfoundry-community/go-cfclient/v3/client"
	"github.com/cloudfoundry-community/go-cfclient/v3/config"
	"github.com/cloudfoundry-community/go-cfclient/v3/resource"
	"os"
)

type HostToAppsDetail struct {
	Host string
	Apps []string
}

var results map[string]*HostToAppsDetail

func main() {
	err := execute()
	if err != nil {
		fmt.Println(err)
		os.Exit(1)
	}
	fmt.Println("Done!")
}

func execute() error {
	// use the CF CLI config and the stored access/refresh token
	cfg, err := config.NewFromCFHome()
	if err != nil {
		return err
	}
	cf, err := client.New(cfg)
	if err != nil {
		return err
	}

	results = make(map[string]*HostToAppsDetail)
	err = listApps(context.Background(), cf)
	if err != nil {
		return err
	}
	return displayResults()
}

func listApps(ctx context.Context, cf *client.Client) error {
	opts := client.NewAppListOptions()
	for {
		apps, pager, err := cf.Applications.List(ctx, opts)
		if err != nil {
			return err
		}
		for _, app := range apps {
			err := listProcessStats(ctx, cf, app)
			if err != nil {
				return err
			}
		}
		if !pager.HasNextPage() {
			break
		}
		pager.NextPage(opts)
	}
	return nil
}

func listProcessStats(ctx context.Context, cf *client.Client, app *resource.App) error {
	stats, err := cf.Processes.GetStatsForApp(ctx, app.GUID, "web")
	if err != nil {
		return err
	}

	host := stats.Stats[0].Host
	d, ok := results[host]
	if !ok {
		d = &HostToAppsDetail{
			Host: host,
			Apps: []string{},
		}
		results[host] = d
	}

	d.Apps = append(d.Apps, app.Name)
	return nil
}

func displayResults() error {
	for _, d := range results {
		fmt.Printf("Host: %s\n", d.Host)
		for _, a := range d.Apps {
			fmt.Printf("    - %s\n", a)
		}
	}
	return nil
}