This commit resolves #221, to specify stacks that are currently on yo…

…ur local machine running.

Signed-off-by: tobigiwa <giwaoluwatobi@gmail.com>

cmd/ps.go

@@ -0,0 +1,74 @@
+/*
+Copyright © 2023 Giwa Oluwatobi <giwaoluwatobi@gmial.com>
+*/
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/hyperledger/firefly-cli/internal/log"
+	"github.com/hyperledger/firefly-cli/internal/stacks"
+	"github.com/spf13/cobra"
+)
+
+// psCmd represents the ps command
+var psCmd = &cobra.Command{
+	Use:   "ps [a stack name]...",
+	Short: "Returns information on running stacks",
+	Long: `ps returns currently running stacks on your local machine.
+	
+	It also takes a continuous list of whitespace optional arguement - stack name.`,
+	Aliases: []string{"process"},
+	RunE: func(cmd *cobra.Command, args []string) error {
+
+		ctx := log.WithVerbosity(context.Background(), verbose)
+		ctx = log.WithLogger(ctx, logger)
+
+		allStacks, err := stacks.ListStacks()
+		if err != nil {
+			return err
+		}
+
+		if len(args) > 0 {
+			namedStacks := make([]string, 0, len(args))
+			for _, stackName := range args {
+				if contains(allStacks, strings.TrimSpace(stackName)) {
+					namedStacks = append(namedStacks, stackName)
+				} else {
+					fmt.Printf("stack name - %s, is not present on your local machine. Run `ff ls` to see all available stacks.\n", stackName)
+				}
+			}
+
+			allStacks = namedStacks // replace only the user specified stacks in the slice instead.
+		}
+
+		stackManager := stacks.NewStackManager(ctx)
+		for _, stackName := range allStacks {
+			if err := stackManager.LoadStack(stackName); err != nil {
+				return err
+			}
+
+			if err := stackManager.IsRunning(); err != nil {
+				return err
+			}
+		}
+		return nil
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(psCmd)
+}
+
+// contains can be removed if the go mod version is bumped to version Go 1.18
+// and replaced with slices.Contains().
+func contains(s []string, str string) bool {
+	for _, v := range s {
+		if v == str {
+			return true
+		}
+	}
+	return false
+}

internal/docker/docker.go

@@ -111,6 +111,12 @@ func RunDockerCommandBuffered(ctx context.Context, workingDir string, command ..
 	return runCommand(ctx, dockerCmd)
 }
 
+func RunDockerComposeCommandReturnsStdout(workingDir string, command ...string) ([]byte, error) {
+	dockerCmd := exec.Command("docker", append([]string{"compose"}, command...)...)
+	dockerCmd.Dir = workingDir
+	return dockerCmd.Output()
+}
+
 func runCommand(ctx context.Context, cmd *exec.Cmd) (string, error) {
 	verbose := log.VerbosityFromContext(ctx)
 	isLogCmd, _ := ctx.Value(CtxIsLogCmdKey{}).(bool)

internal/stacks/stack_manager.go

@@ -27,7 +27,9 @@ import (
 	"path"
 	"path/filepath"
 	"strings"
+	"sync"
 	"syscall"
+	"text/tabwriter"
 	"time"
 
 	"github.com/hyperledger/firefly-cli/internal/blockchain"
@@ -58,21 +60,20 @@ type StackManager struct {
 	blockchainProvider blockchain.IBlockchainProvider
 	tokenProviders     []tokens.ITokensProvider
 	IsOldFileStructure bool
+	once               sync.Once
 }
 
 func ListStacks() ([]string, error) {
-	files, err := ioutil.ReadDir(constants.StacksDir)
+	files, err := os.ReadDir(constants.StacksDir)
 	if err != nil {
 		return nil, err
 	}
 
-	stacks := make([]string, 0)
-	i := 0
+	stacks := make([]string, 0, len(files))
 	for _, f := range files {
 		if f.IsDir() {
 			if exists, err := CheckExists(f.Name()); err == nil && exists {
 				stacks = append(stacks, f.Name())
-				i++
 			}
 		}
 	}
@@ -250,7 +251,7 @@ func (s *StackManager) LoadStack(stackName string) error {
 	if !exists {
 		return fmt.Errorf("stack '%s' does not exist", stackName)
 	}
-	d, err := ioutil.ReadFile(filepath.Join(stackDir, "stack.json"))
+	d, err := os.ReadFile(filepath.Join(stackDir, "stack.json"))
 	if err != nil {
 		return err
 	}
@@ -1103,6 +1104,33 @@ func (s *StackManager) PrintStackInfo() error {
 	return nil
 }
 
+// IsRunning prints to the stdout, the stack name and it status as "running" or "not_running".
+func (s *StackManager) IsRunning() error {
+	output, err := docker.RunDockerComposeCommandReturnsStdout(s.Stack.StackDir, "ps")
+	if err != nil {
+		return err
+	}
+
+	formatHeader := "\n %s\t%s\t  "
+	formatBody := "\n %s\t%s\t"
+
+	w := new(tabwriter.Writer)
+	w.Init(os.Stdout, 8, 8, 8, '\t', 0)
+
+	s.once.Do(func() {
+		fmt.Fprintf(w, formatHeader, "STACK", "STATUS")
+	})
+
+	if strings.Contains(string(output), s.Stack.Name) { // if the output contains the stack name, it means the container is running.
+		fmt.Fprintf(w, formatBody, s.Stack.Name, "running")
+	} else {
+		fmt.Fprintf(w, formatBody, s.Stack.Name, "not_running")
+	}
+	fmt.Fprintln(w)
+	w.Flush()
+	return nil
+}
+
 func (s *StackManager) disableFireflyCoreContainers() error {
 	compose := s.buildDockerCompose()
 	for _, member := range s.Stack.Members {