timecraft: add configuration file

internal/cmd/config.go

@@ -0,0 +1,227 @@
+package cmd
+
+import (
+ "bytes"
+ "context"
+ "encoding/json"
+ "errors"
+ "fmt"
+ "io"
+ "io/fs"
+ "os"
+ "path/filepath"
+
+ "github.com/stealthrocket/timecraft/internal/object"
+ "github.com/stealthrocket/timecraft/internal/print/human"
+ "github.com/stealthrocket/timecraft/internal/timemachine"
+ "gopkg.in/yaml.v3"
+)
+
+const configUsage = `
+Usage: timecraft config [options]
+
+Options:
+ -c, --config Path to the timecraft configuration file (overrides TIMECRAFTCONFIG)
+ --edit Open $EDITOR to edit the configuration
+ -h, --help Show usage information
+ -o, --ouptut format Output format, one of: text, json, yaml
+`
+
+var (
+ // Path to the timecraft configuration; this is set to the value of the
+ // TIMECRAFTCONFIG environment variable if it exists, and can be overwritten
+ // by the --config option.
+ configPath human.Path = "~/.timecraft/config.yaml"
+)
+
+func init() {
+ if v := os.Getenv("TIMECRAFTCONFIG"); v != "" {
+ configPath = human.Path(v)
+ }
+}
+
+func config(ctx context.Context, args []string) error {
+ var (
+ edit bool
+ output = outputFormat("text")
+ )
+
+ flagSet := newFlagSet("timecraft config", configUsage)
+ boolVar(flagSet, &edit, "edit")
+ customVar(flagSet, &output, "o", "output")
+ parseFlags(flagSet, args)
+
+ r, path, err := openConfig()
+ if err != nil {
+ return err
+ }
+ defer r.Close()
+
+ if edit {
+ editor := os.Getenv("EDITOR")
+ if editor == "" {
+ return errors.New(`$EDITOR is not set`)
+ }
+ shell := os.Getenv("SHELL")
+ if shell == "" {
+ shell = "/bin/sh"
+ }
+
+ if err := os.MkdirAll(filepath.Dir(path), 0777); err != nil {
+ if !errors.Is(err, fs.ErrExist) {
+ return err
+ }
+ }
+
+ tmp, err := createTempFile(path, r)
+ if err != nil {
+ return err
+ }
+ defer os.Remove(tmp)
+
+ p, err := os.StartProcess(shell, []string{shell, "-c", editor + " " + tmp}, &os.ProcAttr{
+ Files: []*os.File{
+ 0: os.Stdin,
+ 1: os.Stdout,
+ 2: os.Stderr,
+ },
+ })
+ if err != nil {
+ return err
+ }
+ if _, err := p.Wait(); err != nil {
+ return err
+ }
+ f, err := os.Open(tmp)
+ if err != nil {
+ return err
+ }
+ defer f.Close()
+ if _, err := readConfig(f); err != nil {
+ return fmt.Errorf("not applying configuration updates because the file has a syntax error: %w", err)
+ }
+ if err := os.Rename(tmp, path); err != nil {
+ return err
+ }
+ }
+
+ config, err := loadConfig()
+ if err != nil {
+ return err
+ }
+
+ w := io.Writer(os.Stdout)
+ for {
+ switch output {
+ case "json":
+ e := json.NewEncoder(w)
+ e.SetEscapeHTML(false)
+ e.SetIndent("", " ")
+ _ = e.Encode(config)
+ case "yaml":
+ e := yaml.NewEncoder(w)
+ e.SetIndent(2)
+ _ = e.Encode(config)
+ _ = e.Close()
+ default:
+ r, _, err := openConfig()
+ if err != nil {
+ if errors.Is(err, fs.ErrNotExist) {
+ output = "yaml"
+ continue
+ }
+ return err
+ }
+ defer r.Close()
+ _, _ = io.Copy(w, r)
+ }
+ return nil
+ }
+}
+
+type configuration struct {
+ Registry struct {
+ Location string `json:"location"`
+ } `json:"registry"`
+}
+
+func defaultConfig() *configuration {
+ c := new(configuration)
+ c.Registry.Location = "~/.timecraft"
+ return c
+}
+
+func openConfig() (io.ReadCloser, string, error) {
+ path, err := configPath.Resolve()
+ if err != nil {
+ return nil, path, err
+ }
+ f, err := os.Open(path)
+ if err != nil {
+ if !errors.Is(err, fs.ErrNotExist) {
+ return nil, path, err
+ }
+ c := defaultConfig()
+ b, _ := yaml.Marshal(c)
+ return io.NopCloser(bytes.NewReader(b)), path, nil
+ }
+ return f, path, nil
+}
+
+func loadConfig() (*configuration, error) {
+ r, _, err := openConfig()
+ if err != nil {
+ return nil, err
+ }
+ defer r.Close()
+ return readConfig(r)
+}
+
+func readConfig(r io.Reader) (*configuration, error) {
+ c := defaultConfig()
+ d := yaml.NewDecoder(r)
+ d.KnownFields(true)
+ if err := d.Decode(c); err != nil {
+ return nil, err
+ }
+ return c, nil
+}
+
+func (c *configuration) createRegistry() (*timemachine.Registry, error) {
+ p, err := human.Path(c.Registry.Location).Resolve()
+ if err != nil {
+ return nil, err
+ }
+ if err := os.Mkdir(filepath.Dir(p), 0777); err != nil {
+ if !errors.Is(err, fs.ErrExist) {
+ return nil, err
+ }
+ }
+ return c.openRegistry()
+}
+
+func (c *configuration) openRegistry() (*timemachine.Registry, error) {
+ p, err := human.Path(c.Registry.Location).Resolve()
+ if err != nil {
+ return nil, err
+ }
+ store, err := object.DirStore(p)
+ if err != nil {
+ return nil, err
+ }
+ registry := &timemachine.Registry{
+ Store: store,
+ }
+ return registry, nil
+}
+
+func createTempFile(path string, r io.Reader) (string, error) {
+ dir, file := filepath.Split(path)
+ w, err := os.CreateTemp(dir, "."+file+".*")
+ if err != nil {
+ return "", err
+ }
+ defer w.Close()
+ _, err = io.Copy(w, r)
+ return w.Name(), err
+}

internal/cmd/describe.go

@@ -47,20 +47,18 @@ Examples:
  0 27 1 1.68 KiB 3.88 KiB 1.62 KiB 58.27%
 
 Options:
+ -c, --config Path to the timecraft configuration file (overrides TIMECRAFTCONFIG)
  -h, --help Show this usage information
  -o, --ouptut format Output format, one of: text, json, yaml
- -r, --registry path Path to the timecraft registry (default to ~/.timecraft)
 `
 
 func describe(ctx context.Context, args []string) error {
  var (
- output = outputFormat("text")
- registryPath = human.Path("~/.timecraft")
+ output = outputFormat("text")
  )
 
  flagSet := newFlagSet("timecraft describe", describeUsage)
  customVar(flagSet, &output, "o", "output")
- customVar(flagSet, &registryPath, "r", "registry")
  args = parseFlags(flagSet, args)
 
  if len(args) == 0 {
@@ -71,13 +69,15 @@ func describe(ctx context.Context, args []string) error {
  if err != nil {
  return err
  }
-
  resourceIDs := args[1:]
  if len(resourceIDs) == 0 {
  return fmt.Errorf(`no resources were specified, use 'timecraft describe %s <resources ids...>'`, resource.typ)
  }
-
- registry, err := openRegistry(registryPath)
+ config, err := loadConfig()
+ if err != nil {
+ return err
+ }
+ registry, err := config.openRegistry()
  if err != nil {
  return err
  }

internal/cmd/export.go

@@ -8,7 +8,6 @@ import (
 
  "github.com/google/uuid"
  "github.com/stealthrocket/timecraft/format"
- "github.com/stealthrocket/timecraft/internal/print/human"
 )
 
 const exportUsage = `
@@ -23,17 +22,12 @@ Usage: timecraft export <resource type> <resource id> <output file>
  resource to stdout.
 
 Options:
- -h, --help Show this usage information
- -r, --registry path  Path to the timecraft registry (default to ~/.timecraft)
+ -c, --config Path to the timecraft configuration file (overrides TIMECRAFTCONFIG)
+ -h, --help  Show this usage information
 `
 
 func export(ctx context.Context, args []string) error {
- var (
- registryPath = human.Path("~/.timecraft")
- )
-
  flagSet := newFlagSet("timecraft export", exportUsage)
- customVar(flagSet, &registryPath, "r", "registry")
  args = parseFlags(flagSet, args)
 
  if len(args) != 3 {
@@ -44,8 +38,11 @@ func export(ctx context.Context, args []string) error {
  if err != nil {
  return err
  }
-
- registry, err := openRegistry(registryPath)
+ config, err := loadConfig()
+ if err != nil {
+ return err
+ }
+ registry, err := config.openRegistry()
  if err != nil {
  return err
  }

internal/cmd/get.go

@@ -45,9 +45,9 @@ Examples:
  }
 
 Options:
+ -c, --config Path to the timecraft configuration file (overrides TIMECRAFTCONFIG)
  -h, --help Show this usage information
  -o, --ouptut format Output format, one of: text, json, yaml
- -r, --registry path Path to the timecraft registry (default to ~/.timecraft)
 `
 
 type resource struct {
@@ -116,14 +116,12 @@ var resources = [...]resource{
 
 func get(ctx context.Context, args []string) error {
  var (
- timeRange = timemachine.Since(time.Unix(0, 0))
- output = outputFormat("text")
- registryPath = human.Path("~/.timecraft")
+ timeRange = timemachine.Since(time.Unix(0, 0))
+ output = outputFormat("text")
  )
 
  flagSet := newFlagSet("timecraft get", getUsage)
  customVar(flagSet, &output, "o", "output")
- customVar(flagSet, &registryPath, "r", "registry")
  args = parseFlags(flagSet, args)
 
  if len(args) != 1 {
@@ -133,8 +131,11 @@ func get(ctx context.Context, args []string) error {
  if err != nil {
  return err
  }
-
- registry, err := openRegistry(registryPath)
+ config, err := loadConfig()
+ if err != nil {
+ return err
+ }
+ registry, err := config.openRegistry()
  if err != nil {
  return err
  }

internal/cmd/help.go

@@ -21,9 +21,14 @@ Debugging Commands:
  profile Generate performance profile from execution records
 
 Other Commands:
+ config View or edit the timecraft configuration
  help Show usage information about timecraft commands
  version Show the timecraft version information
 
+Global Options:
+ -c, --config Path to the timecraft configuration file (overrides TIMECRAFTCONFIG)
+ -h, --help Show usage information
+
 For a description of each command, run 'timecraft help <command>'.`
 
 func help(ctx context.Context, args []string) error {
@@ -41,6 +46,8 @@ func help(ctx context.Context, args []string) error {
  }
 
  switch cmd {
+ case "config":
+ msg = configUsage
  case "describe":
  msg = describeUsage
  case "export":