Add dev to upload on every change and tail

internal/dev/dev.go

@@ -0,0 +1,141 @@
+package dev
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"maps"
+	"path/filepath"
+	"slices"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/siliconwitchery/superstack-cli/internal/api"
+	"github.com/siliconwitchery/superstack-cli/internal/files"
+	"github.com/siliconwitchery/superstack-cli/internal/tail"
+)
+
+type serialWriter struct {
+	mutex sync.Mutex
+	out   io.Writer
+}
+
+func (writer *serialWriter) Write(data []byte) (int, error) {
+	writer.mutex.Lock()
+	defer writer.mutex.Unlock()
+
+	return writer.out.Write(data)
+}
+
+func Dev(invocation api.Invocation, arguments []string) error {
+	if len(arguments) < 2 {
+		return errors.New("dev takes an IMEI or fleet id, then the files or directories to upload on every change")
+	}
+
+	target := arguments[0]
+	tailArguments := []string{target}
+	isImei := len(target) == 15 && !strings.ContainsFunc(target, func(digit rune) bool { return digit < '0' || digit > '9' })
+
+	if isImei {
+		devices, err := api.FetchDevices(invocation)
+
+		if err != nil {
+			return err
+		}
+
+		index := slices.IndexFunc(devices, func(device api.DeviceEntry) bool { return device.Imei == target })
+
+		if index < 0 {
+			return fmt.Errorf("device %s is not paired with any of your fleets", target)
+		}
+
+		tailArguments = []string{strconv.FormatInt(devices[index].FleetId, 10), target}
+	}
+
+	invocation.Out = &serialWriter{out: invocation.Out}
+
+	// The first upload, which also checks the arguments
+	err := files.Upload(invocation, arguments)
+
+	if err != nil {
+		return err
+	}
+
+	// The log, whose end is the end of dev
+	tailEnded := make(chan error, 1)
+
+	go func() {
+		tailEnded <- tail.Tail(invocation, tailArguments)
+	}()
+
+	// Upload again once the watched paths have changed and then stayed still for one poll
+	previous := snapshot(arguments[1:])
+	changed := false
+
+	for {
+		select {
+		case err := <-tailEnded:
+			return err
+
+		case <-time.After(500 * time.Millisecond):
+		}
+
+		current := snapshot(arguments[1:])
+
+		if !maps.Equal(current, previous) {
+			previous = current
+			changed = true
+			continue
+		}
+
+		if !changed {
+			continue
+		}
+
+		changed = false
+		err = files.Upload(invocation, arguments)
+
+		if err != nil {
+			fmt.Fprintf(invocation.Out, "superstack: %s\n", err)
+		}
+	}
+}
+
+func snapshot(paths []string) map[string]string {
+	state := map[string]string{}
+
+	for _, argument := range paths {
+		filepath.WalkDir(argument, func(path string, entry fs.DirEntry, walkError error) error {
+			if walkError != nil {
+				return nil
+			}
+
+			if path != argument && strings.HasPrefix(entry.Name(), ".") {
+				if entry.IsDir() {
+					return filepath.SkipDir
+				}
+
+				return nil
+			}
+
+			if !entry.Type().IsRegular() {
+				return nil
+			}
+
+			info, err := entry.Info()
+
+			if err != nil {
+				return nil
+			}
+
+			state[path] = strconv.FormatInt(info.Size(), 10) + " " + info.ModTime().String()
+
+			return nil
+		})
+	}
+
+	return state
+}