Refactor a bit

pkg/app2/app.go

@@ -3,32 +3,43 @@ package app2
 import (
 	"fmt"
 
-	"github.com/skycoin/skywire/pkg/app2/appserver"
-
 	"github.com/skycoin/skycoin/src/util/logging"
+
+	"github.com/skycoin/skywire/pkg/app2/appserver"
 )
 
+// App defines a skywire application. It encapsulates
+// running process and the RPC server to communicate with
+// the app.
 type App struct {
+	key    Key
 	config Config
 	log    *logging.Logger
 	proc   *Proc
 	rpcS   *appserver.Server
 }
 
+// New constructs `App`.
 func New(log *logging.Logger, c Config, args []string) *App {
-	p := NewProc(c, args)
+	k := GenerateAppKey()
+
+	p := NewProc(c, args, k)
 
 	return &App{
+		key:    k,
 		config: c,
 		log:    log,
 		proc:   p,
 	}
 }
 
+// PID returns app PID.
 func (a *App) PID() ProcID {
 	return a.proc.ID()
 }
 
+// Run sets the app running. It starts app process
+// and sets up the RPC server.
 func (a *App) Run() error {
 	appKey := GenerateAppKey()
 
@@ -54,18 +65,22 @@ func (a *App) Run() error {
 	return nil
 }
 
+// Stop stops application (process and the RPC server).
 func (a *App) Stop() error {
 	a.closeRPCServer()
 
 	return a.proc.Stop()
 }
 
+// Wait waits for the app to exit. Shuts down the
+// RPC server.
 func (a *App) Wait() error {
 	err := a.proc.Wait()
 	a.closeRPCServer()
 	return err
 }
 
+// closeRPCServer closes RPC server and logs error if any.
 func (a *App) closeRPCServer() {
 	if err := a.rpcS.Close(); err != nil {
 		a.log.WithError(err).Error("error closing RPC server")

pkg/app2/app_manager.go

@@ -7,18 +7,23 @@ import (
 )
 
 var (
-	ErrAppExists = errors.New("app with such pid already exists")
+	// ErrAppExists is returned when trying to add
+	// app to the manager which already exists.
+	ErrAppExists = errors.New("app with such name already exists")
 )
 
+// AppManager allows to store and retrieve skywire apps.
 type AppManager struct {
 	apps map[string]*App
 	mx   sync.RWMutex
 }
 
+// NewAppManager constructs `AppManager`.
 func NewAppManager() *AppManager {
 	return &AppManager{}
 }
 
+// Add adds app `a` to the manager instance.
 func (m *AppManager) Add(a *App) error {
 	m.mx.Lock()
 	defer m.mx.Unlock()
@@ -32,6 +37,8 @@ func (m *AppManager) Add(a *App) error {
 	return nil
 }
 
+// App gets the app from the manager if it exists. Returns bool
+// flag to indicate operation success.
 func (m *AppManager) App(name string) (*App, bool) {
 	m.mx.RLock()
 	defer m.mx.RUnlock()
@@ -41,6 +48,7 @@ func (m *AppManager) App(name string) (*App, bool) {
 	return a, ok
 }
 
+// Exists checks whether app exists in the manager instance.
 func (m *AppManager) Exists(name string) bool {
 	m.mx.RLock()
 	defer m.mx.RUnlock()
@@ -50,13 +58,16 @@ func (m *AppManager) Exists(name string) bool {
 	return ok
 }
 
+// Remove removes app with the name `name` from the manager instance.
 func (m *AppManager) Remove(name string) {
 	m.mx.Lock()
 	defer m.mx.Unlock()
 
 	delete(m.apps, name)
 }
 
+// Range allows to iterate over stored apps. Calls `next` on each iteration.
+// Stops execution once `next` returns false.
 func (m *AppManager) Range(next func(name string, app *App) bool) {
 	m.mx.RLock()
 	defer m.mx.RUnlock()

pkg/app2/appnet/addr.go

@@ -12,6 +12,8 @@ import (
 )
 
 var (
+	// ErrUnknownAddrType is returned when trying to convert the
+	// unknown addr type.
 	ErrUnknownAddrType = errors.New("addr type is unknown")
 )
 

pkg/app2/appnet/skywire_networker.go

@@ -7,7 +7,6 @@ import (
 	"sync/atomic"
 
 	"github.com/pkg/errors"
-
 	"github.com/skycoin/dmsg/netutil"
 	"github.com/skycoin/skycoin/src/util/logging"
 

pkg/app2/appserver/rpc_gateway.go

@@ -5,11 +5,10 @@ import (
 	"net"
 
 	"github.com/pkg/errors"
-	"github.com/skycoin/skywire/pkg/app2/idmanager"
-
 	"github.com/skycoin/skycoin/src/util/logging"
 
 	"github.com/skycoin/skywire/pkg/app2/appnet"
+	"github.com/skycoin/skywire/pkg/app2/idmanager"
 	"github.com/skycoin/skywire/pkg/routing"
 )
 

pkg/app2/appserver/server.go

@@ -7,10 +7,9 @@ import (
 	"sync"
 
 	"github.com/pkg/errors"
+	"github.com/skycoin/skycoin/src/util/logging"
 
 	"github.com/skycoin/skywire/pkg/app2"
-
-	"github.com/skycoin/skycoin/src/util/logging"
 )
 
 // Server is a server for app/visor communication.
@@ -60,12 +59,15 @@ func (s *Server) ListenAndServe() error {
 	}
 }
 
+// Close closes the server.
 func (s *Server) Close() error {
 	err := s.lis.Close()
 	close(s.stopCh)
+	s.done.Wait()
 	return err
 }
 
+// serveConn serves RPC on a single connection.
 func (s *Server) serveConn(conn net.Conn) {
 	go s.rpcS.ServeConn(conn)
 	<-s.stopCh

pkg/app2/client.go

@@ -5,13 +5,11 @@ import (
 	"net/rpc"
 
 	"github.com/pkg/errors"
-
-	"github.com/skycoin/skywire/pkg/app2/idmanager"
-
 	"github.com/skycoin/dmsg/cipher"
 	"github.com/skycoin/skycoin/src/util/logging"
 
 	"github.com/skycoin/skywire/pkg/app2/appnet"
+	"github.com/skycoin/skywire/pkg/app2/idmanager"
 	"github.com/skycoin/skywire/pkg/routing"
 )
 

pkg/app2/config.go

@@ -1,6 +1,6 @@
 package app2
 
-// Config defines configuration parameters for App
+// Config defines configuration parameters for `App`.
 type Config struct {
 	Name      string `json:"name"`
 	Version   string `json:"version"`

pkg/app2/errors.go

@@ -4,12 +4,6 @@ import (
 	"errors"
 )
 
-var (
-	// ErrPortAlreadyBound is being returned when trying to bind to the port
-	// which is already bound to.
-	ErrPortAlreadyBound = errors.New("port is already bound")
-)
-
 var (
 	// errMethodNotImplemented serves as a return value for non-implemented funcs (stubs).
 	errMethodNotImplemented = errors.New("method not implemented")

pkg/app2/idmanager/util.go

@@ -5,7 +5,7 @@ import (
 	"net"
 )
 
-// assertListener asserts that `v` is of type `net.Listener`.
+// AssertListener asserts that `v` is of type `net.Listener`.
 func AssertListener(v interface{}) (net.Listener, error) {
 	lis, ok := v.(net.Listener)
 	if !ok {
@@ -15,7 +15,7 @@ func AssertListener(v interface{}) (net.Listener, error) {
 	return lis, nil
 }
 
-// assertConn asserts that `v` is of type `net.Conn`.
+// AssertConn asserts that `v` is of type `net.Conn`.
 func AssertConn(v interface{}) (net.Conn, error) {
 	conn, ok := v.(net.Conn)
 	if !ok {

pkg/app2/key.go

@@ -2,8 +2,11 @@ package app2
 
 import "github.com/skycoin/dmsg/cipher"
 
+// Key is an app key to authenticate within the
+// app server.
 type Key string
 
+// GenerateAppKey generates new app key.
 func GenerateAppKey() Key {
 	raw, _ := cipher.GenerateKeyPair()
 	return Key(raw.Hex())

pkg/app2/listener.go

@@ -5,10 +5,10 @@ import (
 	"net"
 	"sync"
 
-	"github.com/skycoin/skywire/pkg/app2/idmanager"
-
 	"github.com/skycoin/skycoin/src/util/logging"
+
 	"github.com/skycoin/skywire/pkg/app2/appnet"
+	"github.com/skycoin/skywire/pkg/app2/idmanager"
 )
 
 // Listener is a listener for app server connections.

pkg/app2/proc.go

@@ -7,12 +7,14 @@ import (
 	"sync"
 )
 
+// Proc is a wrapper for skywire app process.
 type Proc struct {
 	id  ProcID
 	cmd *exec.Cmd
 	mx  sync.RWMutex
 }
 
+// NewProc constructs `Proc`.
 func NewProc(c Config, args []string, key Key) *Proc {
 	binaryPath := getBinaryPath(c.BinaryDir, c.Name, c.Version)
 
@@ -35,13 +37,15 @@ func NewProc(c Config, args []string, key Key) *Proc {
 	}
 }
 
+// ID returns pid of the app.
 func (p *Proc) ID() ProcID {
 	p.mx.RLock()
 	id := p.id
 	p.mx.RUnlock()
 	return id
 }
 
+// Run runs the app process.
 func (p *Proc) Run() error {
 	if err := p.cmd.Run(); err != nil {
 		return err
@@ -54,10 +58,12 @@ func (p *Proc) Run() error {
 	return nil
 }
 
+// Stop stops the app process.
 func (p *Proc) Stop() error {
 	return p.cmd.Process.Kill()
 }
 
+// Wait waits for the app process to exit.
 func (p *Proc) Wait() error {
 	return p.cmd.Wait()
 }

pkg/app2/rpc_client.go

@@ -4,9 +4,8 @@ import (
 	"fmt"
 	"net/rpc"
 
-	"github.com/skycoin/skywire/pkg/app2/appserver"
-
 	"github.com/skycoin/skywire/pkg/app2/appnet"
+	"github.com/skycoin/skywire/pkg/app2/appserver"
 	"github.com/skycoin/skywire/pkg/routing"
 )