Merge "lib/modules: implement a registry to clean up AddFunction,Subprocess etc."
diff --git a/lib/filelocker/locker_test.go b/lib/filelocker/locker_test.go
index d98e093..0060210 100644
--- a/lib/filelocker/locker_test.go
+++ b/lib/filelocker/locker_test.go
@@ -62,7 +62,7 @@
filepath := newFile()
defer os.Remove(filepath)
- sh := modules.NewShell("testLockUnlockChild")
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
h, err := sh.Start("testLockUnlockChild", nil, filepath)
if err != nil {
diff --git a/lib/modules/core/core.go b/lib/modules/core/core.go
index add670f..214d127 100644
--- a/lib/modules/core/core.go
+++ b/lib/modules/core/core.go
@@ -48,8 +48,6 @@
// runs a proxy server
package core
-import "veyron.io/veyron/veyron/lib/modules"
-
const (
// Functions
LSCommand = "ls"
@@ -70,50 +68,3 @@
WSPRCommand = "wsprd"
ShellCommand = "sh"
)
-
-// NewShell returns a new Shell instance with the core commands installed.
-func NewShell() *modules.Shell {
- shell := modules.NewShell("")
- Install(shell)
- return shell
-}
-
-// Install installs the core commands into the supplied Shell.
-func Install(shell *modules.Shell) {
- // Explicitly add the subprocesses so that we can provide a help string
- shell.AddSubprocess(EchoServerCommand, `<message> <name>
- mount an echo server at <name>, it will prepend <message> to its responses`)
- shell.AddSubprocess(EchoClientCommand, `
- <name> <text>
- invoke name.Echo(<text>)`)
- shell.AddSubprocess(RootMTCommand, `run a root mount table
- it will output MT_NAME, MT_ADDR and PID`)
- shell.AddSubprocess(MTCommand, `<name>
- run a mount table mounted at <name>`)
- shell.AddSubprocess(LSExternalCommand, `<glob>
- run a glob command as an external subprocess`)
- shell.AddSubprocess(ProxyServerCommand, `<name>...
- run a proxy server mounted at the specified names`)
- // TODO(sadovsky): It's unfortunate that we must duplicate help strings
- // between RegisterChild and AddSubprocess. Will be fixed by my proposed
- // refactoring.
- shell.AddSubprocess(WSPRCommand, usageWSPR())
- //shell.AddSubprocess(ShellCommand, subshell, "")
-
- shell.AddFunction(LSCommand, ls, `<glob>...
- issues glob requests using the current processes namespace library`)
- shell.AddFunction(ResolveCommand, resolveObject, `<name>
- resolves name to obtain an object server address`)
- shell.AddFunction(ResolveMTCommand, resolveMT, `<name>
- resolves name to obtain a mount table address`)
- shell.AddFunction(SetNamespaceRootsCommand, setNamespaceRoots, `<name>...
- set the in-process namespace roots to <name>...`)
- shell.AddFunction(SleepCommand, sleep, `[duration]
- sleep for a time (in go time.Duration format): defaults to 1s`)
- shell.AddFunction(TimeCommand, now, `
- prints the current time`)
- shell.AddFunction(NamespaceCacheCommand, namespaceCache, `on|off
- turns the namespace cache on or off`)
- shell.AddFunction(MountCommand, mountServer, `<mountpoint> <server> <ttl> [M][R]
- invokes namespace.Mount(<mountpoint>, <server>, <ttl>)`)
-}
diff --git a/lib/modules/core/core_test.go b/lib/modules/core/core_test.go
index 1cc69e2..5f72ee9 100644
--- a/lib/modules/core/core_test.go
+++ b/lib/modules/core/core_test.go
@@ -23,7 +23,7 @@
)
func TestCommands(t *testing.T) {
- sh := core.NewShell()
+ sh := modules.NewShell()
defer sh.Cleanup(nil, os.Stderr)
for _, c := range []string{core.RootMTCommand, core.MTCommand} {
if len(sh.Help(c)) == 0 {
@@ -38,7 +38,7 @@
}
func newShell() (*modules.Shell, func()) {
- sh := core.NewShell()
+ sh := modules.NewShell()
return sh, func() {
if testing.Verbose() {
vlog.Infof("------ cleanup ------")
diff --git a/lib/modules/core/misc.go b/lib/modules/core/misc.go
index 577f3b2..35b54c2 100644
--- a/lib/modules/core/misc.go
+++ b/lib/modules/core/misc.go
@@ -11,6 +11,19 @@
"veyron.io/veyron/veyron/lib/modules"
)
+func init() {
+
+ modules.RegisterFunction(NamespaceCacheCommand, `on|off
+ turns the namespace cache on or off`, namespaceCache)
+ modules.RegisterFunction(MountCommand, `<mountpoint> <server> <ttl> [M][R]
+ invokes namespace.Mount(<mountpoint>, <server>, <ttl>)`, mountServer)
+ modules.RegisterFunction(SleepCommand, `[duration]
+ sleep for a time(in go time.Duration format): defaults to 1s`, sleep)
+ modules.RegisterFunction(TimeCommand, `
+ prints the current time`, now)
+
+}
+
func sleep(stdin io.Reader, stdout, stderr io.Writer, env map[string]string, args ...string) error {
d := time.Second
if len(args) > 1 {
diff --git a/lib/modules/core/mounttable.go b/lib/modules/core/mounttable.go
index 7d5d7f8..51373a6 100644
--- a/lib/modules/core/mounttable.go
+++ b/lib/modules/core/mounttable.go
@@ -22,6 +22,18 @@
modules.RegisterChild(LSExternalCommand, `<glob>...
issues glob requests using the current processes namespace library`,
ls)
+ modules.RegisterFunction(LSCommand, `<glob>...
+ issues glob requests using the current processes namespace library`, ls)
+ modules.RegisterFunction(ResolveCommand, `<name>
+ resolves name to obtain an object server address`, resolveObject)
+ modules.RegisterFunction(ResolveMTCommand, `<name>
+ resolves name to obtain a mount table address`, resolveMT)
+ modules.RegisterFunction(SetNamespaceRootsCommand, `<name>...
+ set the in-process namespace roots to <name>...`, setNamespaceRoots)
+ modules.RegisterFunction(NamespaceCacheCommand, `on|off
+ turns the namespace cache on or off`, namespaceCache)
+ modules.RegisterFunction(MountCommand, `<mountpoint> <server> <ttl> [M][R]
+ invokes namespace.Mount(<mountpoint>, <server>, <ttl>)`, mountServer)
}
func mountTable(stdin io.Reader, stdout, stderr io.Writer, env map[string]string, args ...string) error {
diff --git a/lib/modules/exec.go b/lib/modules/exec.go
index 6d45f6c..d656d0a 100644
--- a/lib/modules/exec.go
+++ b/lib/modules/exec.go
@@ -2,11 +2,9 @@
import (
"flag"
- "fmt"
"io"
"os"
"os/exec"
- "regexp"
"strings"
"sync"
"time"
@@ -63,14 +61,8 @@
return runFlag.Value.String() == "TestHelperProcess"
}
-// IsModulesProcess returns true if this process is run using
-// the modules package.
-func IsModulesProcess() bool {
- return os.Getenv(ShellEntryPoint) != ""
-}
-
func newExecHandle(name string) command {
- return &execHandle{name: name, entryPoint: ShellEntryPoint + "=" + name}
+ return &execHandle{name: name, entryPoint: shellEntryPoint + "=" + name}
}
func (eh *execHandle) Stdout() io.Reader {
@@ -101,11 +93,11 @@
newargs := []string{os.Args[0]}
newargs = append(newargs, testFlags()...)
newargs = append(newargs, args...)
- // Be careful to remove any existing ShellEntryPoint env vars. This
+ // Be careful to remove any existing shellEntryPoint env vars. This
// can happen when subprocesses run other subprocesses etc.
cleaned := make([]string, 0, len(env)+1)
for _, e := range env {
- if strings.HasPrefix(e, ShellEntryPoint+"=") {
+ if strings.HasPrefix(e, shellEntryPoint+"=") {
continue
}
cleaned = append(cleaned, e)
@@ -194,126 +186,3 @@
}
return procErr
}
-
-const ShellEntryPoint = "VEYRON_SHELL_HELPER_PROCESS_ENTRY_POINT"
-
-func RegisterChild(name, help string, main Main) {
- child.Lock()
- defer child.Unlock()
- child.mains[name] = &childEntryPoint{main, help}
-}
-
-// DispatchInTest will execute the requested subproccess command from within
-// a unit test run as a subprocess.
-func DispatchInTest() {
- if !IsTestHelperProcess() {
- return
- }
- if err := child.dispatch(); err != nil {
- vlog.Fatalf("Failed: %s", err)
- }
- os.Exit(0)
-}
-
-// Dispatch will execute the requested subprocess command from a within a
-// a subprocess that is not a unit test.
-func Dispatch() error {
- if IsTestHelperProcess() {
- return fmt.Errorf("use DispatchInTest in unittests")
- }
- return child.dispatch()
-}
-
-func (child *childRegistrar) hasCommand(name string) bool {
- child.Lock()
- _, present := child.mains[name]
- child.Unlock()
- return present
-}
-
-func (child *childRegistrar) dispatch() error {
- ch, err := vexec.GetChildHandle()
- if err != nil {
- // This is for debugging only. It's perfectly reasonable for this
- // error to occur if the process is started by a means other
- // than the exec library.
- vlog.VI(1).Infof("failed to get child handle: %s", err)
- }
-
- // Only signal that the child is ready or failed if we successfully get
- // a child handle. We most likely failed to get a child handle
- // because the subprocess was run directly from the command line.
- command := os.Getenv(ShellEntryPoint)
- if len(command) == 0 {
- err := fmt.Errorf("Failed to find entrypoint %q", ShellEntryPoint)
- if ch != nil {
- ch.SetFailed(err)
- }
- return err
- }
-
- child.Lock()
- m := child.mains[command]
- child.Unlock()
-
- if m == nil {
- err := fmt.Errorf("Shell command %q not registered", command)
- if ch != nil {
- ch.SetFailed(err)
- }
- return err
- }
-
- if ch != nil {
- ch.SetReady()
- }
-
- go func(pid int) {
- for {
- _, err := os.FindProcess(pid)
- if err != nil {
- vlog.Fatalf("Looks like our parent exited: %v", err)
- }
- time.Sleep(time.Second)
- }
- }(os.Getppid())
-
- args := append([]string{command}, flag.Args()...)
- return m.fn(os.Stdin, os.Stdout, os.Stderr, envSliceToMap(os.Environ()), args...)
-}
-
-func (child *childRegistrar) addSubprocesses(sh *Shell, pattern string) error {
- re, err := regexp.Compile(pattern)
- if err != nil {
- return err
- }
- child.Lock()
- defer child.Unlock()
- found := false
- for name, subproc := range child.mains {
- if re.MatchString(name) {
- sh.addSubprocess(name, subproc.help)
- found = true
- }
- }
- if !found {
- return fmt.Errorf("patterh %q failed to match any registered commands", pattern)
- }
- return nil
-}
-
-// AddRegisteredSubprocesses adds any commands that match the regexp pattern
-// to the supplied shell.
-func AddRegisteredSubprocesses(sh *Shell, pattern string) error {
- return child.addSubprocesses(sh, pattern)
-}
-
-// WaitForEof returns when a read on its io.Reader parameter returns io.EOF
-func WaitForEOF(stdin io.Reader) {
- buf := [1024]byte{}
- for {
- if _, err := stdin.Read(buf[:]); err == io.EOF {
- return
- }
- }
-}
diff --git a/lib/modules/modules_internal_test.go b/lib/modules/modules_internal_test.go
index 07e76bc..d0112e6 100644
--- a/lib/modules/modules_internal_test.go
+++ b/lib/modules/modules_internal_test.go
@@ -8,10 +8,6 @@
"testing"
)
-func init() {
- RegisterChild("echos", "[args]*", Echo)
-}
-
func Echo(stdin io.Reader, stdout, stderr io.Writer, env map[string]string, args ...string) error {
if len(args) == 0 {
return fmt.Errorf("no args")
@@ -30,19 +26,18 @@
}
func TestState(t *testing.T) {
- sh := NewShell("echos")
- sh.AddSubprocess("echonotregistered", "[args]*")
- sh.AddFunction("echof", Echo, "[args]*")
+ sh := NewShell()
+ RegisterFunction("echoff", "[args]*", Echo)
assertNumHandles(t, sh, 0)
_, _ = sh.Start("echonotregistered", nil) // won't start.
hs, _ := sh.Start("echos", nil, "a")
- hf, _ := sh.Start("echof", nil, "b")
+ hf, _ := sh.Start("echoff", nil, "b")
assertNumHandles(t, sh, 2)
for i, h := range []Handle{hs, hf} {
if got := h.Shutdown(nil, nil); got != nil {
- t.Errorf("%d: got %q, want %q", i, got, nil)
+ t.Errorf("%d: got %q, want %v", i, got, nil)
}
}
assertNumHandles(t, sh, 0)
diff --git a/lib/modules/modules_test.go b/lib/modules/modules_test.go
index e155934..0fbab39 100644
--- a/lib/modules/modules_test.go
+++ b/lib/modules/modules_test.go
@@ -6,6 +6,7 @@
"fmt"
"io"
"os"
+ "reflect"
"strings"
"testing"
"time"
@@ -19,8 +20,13 @@
testutil.Init()
modules.RegisterChild("envtest", "envtest: <variables to print>...", PrintFromEnv)
modules.RegisterChild("printenv", "printenv", PrintEnv)
- modules.RegisterChild("echo", "[args]*", Echo)
- modules.RegisterChild("errortest", "", ErrorMain)
+ modules.RegisterChild("echos", "[args]*", Echo)
+ modules.RegisterChild("errortestChild", "", ErrorMain)
+
+ modules.RegisterFunction("envtestf", "envtest: <variables to print>...", PrintFromEnv)
+ modules.RegisterFunction("echof", "[args]*", Echo)
+ modules.RegisterFunction("errortestFunc", "", ErrorMain)
+
}
func Echo(stdin io.Reader, stdout, stderr io.Writer, env map[string]string, args ...string) error {
@@ -111,7 +117,7 @@
}
func TestChild(t *testing.T) {
- sh := modules.NewShell("envtest")
+ sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
key, val := "simpleVar", "foo & bar"
sh.SetVar(key, val)
@@ -125,24 +131,23 @@
sh.SetVar(key, val)
testCommand(t, sh, "envtest", key, val)
_, err := sh.Start("non-existent-command", nil, "random", "args")
- if err == nil || err.Error() != `Shell command "non-existent-command" not registered` {
- t.Fatalf("unexpected error %v", err)
+ if err == nil {
+ t.Fatalf("expected error")
}
}
func TestFunction(t *testing.T) {
- sh := modules.NewShell(".*")
+ sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
key, val := "simpleVar", "foo & bar & baz"
sh.SetVar(key, val)
- sh.AddFunction("envtestf", PrintFromEnv, "envtest: <variables to print>...")
testCommand(t, sh, "envtestf", key, val)
}
func TestErrorChild(t *testing.T) {
- sh := modules.NewShell("errortest")
+ sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
- h, err := sh.Start("errortest", nil)
+ h, err := sh.Start("errortestChild", nil)
if err != nil {
t.Fatalf("unexpected error: %s", err)
}
@@ -151,16 +156,16 @@
}
}
-func testShutdown(t *testing.T, sh *modules.Shell, isfunc bool) {
+func testShutdown(t *testing.T, sh *modules.Shell, command string, isfunc bool) {
result := ""
args := []string{"a", "b c", "ddd"}
- if _, err := sh.Start("echo", nil, args...); err != nil {
+ if _, err := sh.Start(command, nil, args...); err != nil {
t.Fatalf("unexpected error: %s", err)
}
var stdoutBuf bytes.Buffer
var stderrBuf bytes.Buffer
sh.Cleanup(&stdoutBuf, &stderrBuf)
- stdoutOutput, stderrOutput := "stdout: echo\n", "stderr: echo\n"
+ stdoutOutput, stderrOutput := "stdout: "+command+"\n", "stderr: "+command+"\n"
for _, a := range args {
stdoutOutput += fmt.Sprintf("stdout: %s\n", a)
stderrOutput += fmt.Sprintf("stderr: %s\n", a)
@@ -177,21 +182,17 @@
}
func TestShutdownSubprocess(t *testing.T) {
- sh := modules.NewShell("echo")
- testShutdown(t, sh, false)
+ testShutdown(t, modules.NewShell(), "echos", false)
}
func TestShutdownFunction(t *testing.T) {
- sh := modules.NewShell()
- sh.AddFunction("echo", Echo, "[args]*")
- testShutdown(t, sh, true)
+ testShutdown(t, modules.NewShell(), "echof", true)
}
func TestErrorFunc(t *testing.T) {
sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
- sh.AddFunction("errortest", ErrorMain, "")
- h, err := sh.Start("errortest", nil)
+ h, err := sh.Start("errortestFunc", nil)
if err != nil {
t.Fatalf("unexpected error: %s", err)
}
@@ -210,7 +211,7 @@
}
func TestEnvelope(t *testing.T) {
- sh := modules.NewShell("printenv")
+ sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
sh.SetVar("a", "1")
sh.SetVar("b", "2")
@@ -258,7 +259,7 @@
}
func TestEnvMerge(t *testing.T) {
- sh := modules.NewShell("printenv")
+ sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
sh.SetVar("a", "1")
os.Setenv("a", "wrong, should be 1")
@@ -285,14 +286,23 @@
}
}
+func TestSetEntryPoint(t *testing.T) {
+ env := map[string]string{"a": "a", "b": "b"}
+ nenv := modules.SetEntryPoint(env, "eg1")
+ if got, want := len(nenv), 3; got != want {
+ t.Errorf("got %d, want %d", got, want)
+ }
+ nenv = modules.SetEntryPoint(env, "eg2")
+ if got, want := len(nenv), 3; got != want {
+ t.Errorf("got %d, want %d", got, want)
+ }
+ if got, want := nenv, []string{"a=a", "b=b", "VEYRON_SHELL_HELPER_PROCESS_ENTRY_POINT=eg2"}; !reflect.DeepEqual(got, want) {
+ t.Errorf("got %d, want %d", got, want)
+ }
+}
+
func TestHelperProcess(t *testing.T) {
modules.DispatchInTest()
}
-// TODO(cnicolaou): more complete tests for environment variables,
-// OS being overridden by Shell for example.
-//
-// TODO(cnicolaou): test for one or either of the io.Writers being nil
-// on calls to Shutdown
-//
// TODO(cnicolaou): test for error return from cleanup
diff --git a/lib/modules/registry.go b/lib/modules/registry.go
new file mode 100644
index 0000000..61325d2
--- /dev/null
+++ b/lib/modules/registry.go
@@ -0,0 +1,184 @@
+package modules
+
+import (
+ "flag"
+ "fmt"
+ "io"
+ "os"
+ "strings"
+ "sync"
+ "time"
+
+ "veyron.io/veyron/veyron2/vlog"
+
+ vexec "veyron.io/veyron/veyron/lib/exec"
+)
+
+type commandDesc struct {
+ factory func() command
+ main Main
+ help string
+}
+
+type cmdRegistry struct {
+ sync.Mutex
+ cmds map[string]*commandDesc
+}
+
+var registry = &cmdRegistry{cmds: make(map[string]*commandDesc)}
+
+func (r *cmdRegistry) addCommand(name, help string, factory func() command, main Main) {
+ r.Lock()
+ defer r.Unlock()
+ r.cmds[name] = &commandDesc{factory, main, help}
+}
+
+func (r *cmdRegistry) getCommand(name string) *commandDesc {
+ r.Lock()
+ defer r.Unlock()
+ return r.cmds[name]
+}
+
+// RegisterChild adds a new command to the registery that will be run
+// as a subprocess. It must be called before Dispatch or DispatchInTest is
+// called, typically from an init function.
+func RegisterChild(name, help string, main Main) {
+ factory := func() command { return newExecHandle(name) }
+ registry.addCommand(name, help, factory, main)
+}
+
+// RegisterFunction adds a new command to the registry that will be run
+// within the current process. It can be called at any time prior to an
+// attempt to use it.
+func RegisterFunction(name, help string, main Main) {
+ factory := func() command { return newFunctionHandle(name, main) }
+ registry.addCommand(name, help, factory, main)
+}
+
+// Help returns the help message for the specified command, or a list
+// of all commands if the command parameter is an empty string.
+func Help(command string) string {
+ return registry.help(command)
+}
+
+func (r *cmdRegistry) help(command string) string {
+ r.Lock()
+ defer r.Unlock()
+ if len(command) == 0 {
+ h := ""
+ for c, _ := range r.cmds {
+ h += c + ", "
+ }
+ return strings.TrimRight(h, ", ")
+ }
+ if c := r.cmds[command]; c != nil {
+ return command + ": " + c.help
+ }
+ return ""
+}
+
+const shellEntryPoint = "VEYRON_SHELL_HELPER_PROCESS_ENTRY_POINT"
+
+// IsModulesProcess returns true if this process is run using
+// the modules package.
+func IsModulesProcess() bool {
+ return os.Getenv(shellEntryPoint) != ""
+}
+
+// SetEntryPoint returns a slice of strings that is guaranteed to contain
+// one and only instance of the entry point environment variable set to the
+// supplied name value.
+func SetEntryPoint(env map[string]string, name string) []string {
+ newEnv := make([]string, 0, len(env)+1)
+ for k, v := range env {
+ if k == shellEntryPoint {
+ continue
+ }
+ newEnv = append(newEnv, k+"="+v)
+ }
+ return append(newEnv, shellEntryPoint+"="+name)
+}
+
+// DispatchInTest will execute the requested subproccess command from within
+// a unit test run as a subprocess.
+func DispatchInTest() {
+ if !IsTestHelperProcess() {
+ return
+ }
+ if err := registry.dispatch(); err != nil {
+ vlog.Fatalf("Failed: %s", err)
+ }
+ os.Exit(0)
+}
+
+// Dispatch will execute the requested subprocess command from a within a
+// a subprocess that is not a unit test. It will return without an error
+// if it is executed by a process that does not specify an entry point
+// in its environment.
+func Dispatch() error {
+ if !IsModulesProcess() {
+ return nil
+ }
+ if IsTestHelperProcess() {
+ return fmt.Errorf("use DispatchInTest in unittests")
+ }
+ return registry.dispatch()
+}
+
+func (r *cmdRegistry) dispatch() error {
+ ch, err := vexec.GetChildHandle()
+ if err != nil {
+ // This is for debugging only. It's perfectly reasonable for this
+ // error to occur if the process is started by a means other
+ // than the exec library.
+ vlog.VI(1).Infof("failed to get child handle: %s", err)
+ }
+
+ // Only signal that the child is ready or failed if we successfully get
+ // a child handle. We most likely failed to get a child handle
+ // because the subprocess was run directly from the command line.
+ command := os.Getenv(shellEntryPoint)
+ if len(command) == 0 {
+ err := fmt.Errorf("Failed to find entrypoint %q", command)
+ if ch != nil {
+ ch.SetFailed(err)
+ }
+ return err
+ }
+
+ m := registry.getCommand(command)
+ if m == nil {
+ err := fmt.Errorf("%s: not registered", command)
+ if ch != nil {
+ ch.SetFailed(err)
+ }
+ return err
+ }
+
+ if ch != nil {
+ ch.SetReady()
+ }
+
+ go func(pid int) {
+ for {
+ _, err := os.FindProcess(pid)
+ if err != nil {
+ vlog.Fatalf("Looks like our parent exited: %v", err)
+ }
+ time.Sleep(time.Second)
+ }
+ }(os.Getppid())
+
+ args := append([]string{command}, flag.Args()...)
+ return m.main(os.Stdin, os.Stdout, os.Stderr, envSliceToMap(os.Environ()), args...)
+}
+
+// WaitForEof returns when a read on its io.Reader parameter returns io.EOF
+func WaitForEOF(stdin io.Reader) {
+ buf := [1024]byte{}
+ for {
+ if _, err := stdin.Read(buf[:]); err == io.EOF {
+ return
+ }
+ }
+}
diff --git a/lib/modules/shell.go b/lib/modules/shell.go
index 535cc01..9e4c3b9 100644
--- a/lib/modules/shell.go
+++ b/lib/modules/shell.go
@@ -1,21 +1,15 @@
// Package modules provides a mechanism for running commonly used services
// as subprocesses and client functionality for accessing those services.
// Such services and functions are collectively called 'commands' and are
-// registered with and executed within a context, defined by the Shell type.
-// The Shell is analagous to the original UNIX shell and maintains a
-// key, value store of variables that is accessible to all of the commands that
-// it hosts. These variables may be referenced by the arguments passed to
-// commands.
+// registered with a single, per-process, registry, but executed within a
+// context, defined by the Shell type. The Shell is analagous to the original
+// UNIX shell and maintains a key, value store of variables that is accessible
+// to all of the commands that it hosts. These variables may be referenced by
+// the arguments passed to commands.
//
-// Commands are added to a shell in two ways: one for a subprocess and another
-// for an inprocess function.
-//
-// - subprocesses are added using the AddSubprocess method in the parent
-// and by the modules.RegisterChild function in the child process (typically
-// RegisterChild is called from an init function). modules.Dispatch must
-// be called in the child process to execute the subprocess 'Main' function
-// provided to RegisterChild.
-// - inprocess functions are added using the AddFunction method.
+// Commands are added to the registry in two ways:
+// - via RegisterChild for a subprocess
+// - via RegisterFunction for an in-process function
//
// In all cases commands are started by invoking the Start method on the
// Shell with the name of the command to run. An instance of the Handle
@@ -42,60 +36,34 @@
import (
"flag"
+ "fmt"
"io"
"io/ioutil"
"os"
- "strings"
"sync"
"time"
"veyron.io/veyron/veyron/lib/exec"
"veyron.io/veyron/veyron/lib/flags/consts"
- "veyron.io/veyron/veyron2/vlog"
)
// Shell represents the context within which commands are run.
type Shell struct {
mu sync.Mutex
env map[string]string
- cmds map[string]*commandDesc
handles map[Handle]struct{}
credDir string
startTimeout time.Duration
config exec.Config
}
-type commandDesc struct {
- factory func() command
- help string
-}
-
-type childEntryPoint struct {
- fn Main
- help string
-}
-
-type childRegistrar struct {
- sync.Mutex
- mains map[string]*childEntryPoint
-}
-
-var child = &childRegistrar{mains: make(map[string]*childEntryPoint)}
-
// NewShell creates a new instance of Shell. If this new instance is is a test
// and no credentials have been configured in the environment via
// consts.VeyronCredentials then CreateAndUseNewCredentials will be used to
-// configure a new ID for the shell and its children. NewShell takes optional
-// regexp patterns that can be used to specify subprocess commands that are
-// implemented in the same binary as this shell (i.e. have been registered
-// using modules.RegisterChild) to be automatically added to it. If the
-// patterns fail to match any such command then they have no effect.
-func NewShell(patterns ...string) *Shell {
- // TODO(cnicolaou): should create a new identity if one doesn't
- // already exist
+// configure a new ID for the shell and its children.
+func NewShell() *Shell {
sh := &Shell{
env: make(map[string]string),
- cmds: make(map[string]*commandDesc),
handles: make(map[Handle]struct{}),
startTimeout: time.Minute,
config: exec.NewConfig(),
@@ -106,9 +74,6 @@
panic(err)
}
}
- for _, pattern := range patterns {
- child.addSubprocesses(sh, pattern)
- }
return sh
}
@@ -134,51 +99,15 @@
type Main func(stdin io.Reader, stdout, stderr io.Writer, env map[string]string, args ...string) error
-// AddSubprocess adds a new command to the Shell that will be run
-// as a subprocess. In addition, the child process must call RegisterChild
-// using the same name used here and provide the function to be executed
-// in the child.
-func (sh *Shell) AddSubprocess(name, help string) {
- if !child.hasCommand(name) {
- vlog.Infof("Warning: %q is not registered with modules.Dispatcher", name)
- }
- sh.addSubprocess(name, help)
-}
-
-func (sh *Shell) addSubprocess(name string, help string) {
- sh.mu.Lock()
- sh.cmds[name] = &commandDesc{func() command { return newExecHandle(name) }, help}
- sh.mu.Unlock()
-}
-
-// AddFunction adds a new command to the Shell that will be run
-// within the current process.
-func (sh *Shell) AddFunction(name string, main Main, help string) {
- sh.mu.Lock()
- sh.cmds[name] = &commandDesc{func() command { return newFunctionHandle(name, main) }, help}
- sh.mu.Unlock()
-}
-
// String returns a string representation of the Shell, which is a
// list of the commands currently available in the shell.
func (sh *Shell) String() string {
- sh.mu.Lock()
- defer sh.mu.Unlock()
- h := ""
- for n, _ := range sh.cmds {
- h += n + ", "
- }
- return strings.TrimRight(h, ", ")
+ return registry.help("")
}
// Help returns the help message for the specified command.
func (sh *Shell) Help(command string) string {
- sh.mu.Lock()
- defer sh.mu.Unlock()
- if c := sh.cmds[command]; c != nil {
- return command + ": " + c.help
- }
- return ""
+ return registry.help(command)
}
// Start starts the specified command, it returns a Handle which can be used
@@ -191,16 +120,14 @@
// error is returned, in which case it may be used to retrieve any output
// from the failed command.
//
-// Commands may have already been registered with the Shell using AddFunction
-// or AddSubprocess, but if not, they will treated as subprocess commands
-// and an attempt made to run them. Such 'dynamically' started subprocess
-// commands are not remembered the by Shell and do not provide a 'help'
-// message etc; their handles are remembered and will be acted on by
-// the Cleanup method. If the non-registered subprocess command does not
-// exist then the Start command will return an error.
+// Commands must have already been registered using RegisterFunction
+// or RegisterChild.
func (sh *Shell) Start(name string, env []string, args ...string) (Handle, error) {
cenv := sh.MergedEnv(env)
- cmd := sh.getCommand(name)
+ cmd := registry.getCommand(name)
+ if cmd == nil {
+ return nil, fmt.Errorf("%s: not registered", name)
+ }
expanded := append([]string{name}, sh.expand(args...)...)
h, err := cmd.factory().start(sh, cenv, expanded...)
if err != nil {
@@ -214,16 +141,6 @@
return h, nil
}
-func (sh *Shell) getCommand(name string) *commandDesc {
- sh.mu.Lock()
- cmd := sh.cmds[name]
- sh.mu.Unlock()
- if cmd == nil {
- cmd = &commandDesc{func() command { return newExecHandle(name) }, ""}
- }
- return cmd
-}
-
// SetStartTimeout sets the timeout for starting subcommands.
func (sh *Shell) SetStartTimeout(d time.Duration) {
sh.startTimeout = d
@@ -233,7 +150,11 @@
// used for running the subprocess or function if it were started with the
// specifed arguments.
func (sh *Shell) CommandEnvelope(name string, env []string, args ...string) ([]string, []string) {
- return sh.getCommand(name).factory().envelope(sh, sh.MergedEnv(env), args...)
+ cmd := registry.getCommand(name)
+ if cmd == nil {
+ return []string{}, []string{}
+ }
+ return cmd.factory().envelope(sh, sh.MergedEnv(env), args...)
}
// Forget tells the Shell to stop tracking the supplied Handle. This is
diff --git a/lib/signals/signals_test.go b/lib/signals/signals_test.go
index e101277..d57c65c 100644
--- a/lib/signals/signals_test.go
+++ b/lib/signals/signals_test.go
@@ -113,7 +113,6 @@
func newShell(t *testing.T, command string) (*modules.Shell, modules.Handle, *expect.Session) {
sh := modules.NewShell()
- sh.AddSubprocess(command, "")
handle, err := sh.Start(command, nil)
if err != nil {
sh.Cleanup(os.Stderr, os.Stderr)
@@ -330,7 +329,6 @@
defer r.Cleanup()
sh := modules.NewShell()
- sh.AddSubprocess("handleDefaults", "")
defer sh.Cleanup(os.Stderr, os.Stderr)
// Set the child process up with a blessing from the parent so that
diff --git a/runtimes/google/ipc/client_test.go b/runtimes/google/ipc/client_test.go
index c77320f..c4e8b8a 100644
--- a/runtimes/google/ipc/client_test.go
+++ b/runtimes/google/ipc/client_test.go
@@ -26,8 +26,7 @@
}
func runMountTable(t *testing.T) (*modules.Shell, func()) {
- sh := modules.NewShell(".*")
- core.Install(sh)
+ sh := modules.NewShell()
root, err := sh.Start(core.RootMTCommand, nil, testArgs()...)
if err != nil {
t.Fatalf("unexpected error for root mt: %s", err)
diff --git a/runtimes/google/ipc/stream/manager/manager_test.go b/runtimes/google/ipc/stream/manager/manager_test.go
index 19dd942..8d4d872 100644
--- a/runtimes/google/ipc/stream/manager/manager_test.go
+++ b/runtimes/google/ipc/stream/manager/manager_test.go
@@ -544,7 +544,7 @@
func TestServerRestartDuringClientLifetime(t *testing.T) {
client := InternalNew(naming.FixedRoutingID(0xcccccccc))
- sh := modules.NewShell(".*")
+ sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
h, err := sh.Start("runServer", nil, "127.0.0.1:0")
if err != nil {
@@ -583,7 +583,7 @@
func TestServerRestartDuringClientLifetimeWS(t *testing.T) {
client := InternalNew(naming.FixedRoutingID(0xcccccccc))
- sh := modules.NewShell(".*")
+ sh := modules.NewShell()
defer sh.Cleanup(nil, nil)
h, err := sh.Start("runServer", nil, "127.0.0.1:0")
if err != nil {
diff --git a/runtimes/google/rt/mgmt_test.go b/runtimes/google/rt/mgmt_test.go
index cd3db2a..defc3c7 100644
--- a/runtimes/google/rt/mgmt_test.go
+++ b/runtimes/google/rt/mgmt_test.go
@@ -116,7 +116,7 @@
// TestNoWaiters verifies that the child process exits in the absence of any
// wait channel being registered with its runtime.
func TestNoWaiters(t *testing.T) {
- sh := modules.NewShell(noWaitersCmd)
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
h, err := sh.Start(noWaitersCmd, nil)
if err != nil {
@@ -143,7 +143,7 @@
// TestForceStop verifies that ForceStop causes the child process to exit
// immediately.
func TestForceStop(t *testing.T) {
- sh := modules.NewShell(forceStopCmd)
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
h, err := sh.Start(forceStopCmd, nil)
if err != nil {
@@ -295,7 +295,7 @@
childcreds := security.NewVeyronCredentials(r.Principal(), appCmd)
configServer, configServiceName, ch := createConfigServer(t, r)
- sh := modules.NewShell(appCmd)
+ sh := modules.NewShell()
sh.SetVar(consts.VeyronCredentials, childcreds)
sh.SetConfigKey(mgmt.ParentNameConfigKey, configServiceName)
sh.SetConfigKey(mgmt.ProtocolConfigKey, "tcp")
diff --git a/runtimes/google/rt/rt_test.go b/runtimes/google/rt/rt_test.go
index 84085db..ff0ae22 100644
--- a/runtimes/google/rt/rt_test.go
+++ b/runtimes/google/rt/rt_test.go
@@ -70,7 +70,7 @@
}
func TestInitArgs(t *testing.T) {
- sh := modules.NewShell("child")
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
h, err := sh.Start("child", nil, "--logtostderr=true", "--vv=3", "--", "foobar")
if err != nil {
@@ -136,7 +136,7 @@
if err != nil {
return err
}
- sh := modules.NewShell("principal")
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
h, err := sh.Start("principal", nil, args[1:]...)
if err != nil {
@@ -191,7 +191,7 @@
}
func TestPrincipalInheritance(t *testing.T) {
- sh := modules.NewShell("principal", "runner")
+ sh := modules.NewShell()
defer func() {
sh.Cleanup(os.Stdout, os.Stderr)
}()
@@ -259,7 +259,7 @@
t.Fatal(err)
}
- sh := modules.NewShell("principal")
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
pubkey, err := collect(sh, "principal", nil)
diff --git a/runtimes/google/rt/signal_test.go b/runtimes/google/rt/signal_test.go
index de2d98c..df93748 100644
--- a/runtimes/google/rt/signal_test.go
+++ b/runtimes/google/rt/signal_test.go
@@ -73,7 +73,7 @@
}
func TestWithRuntime(t *testing.T) {
- sh := modules.NewShell("withRuntime")
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
h, err := sh.Start("withRuntime", nil)
if err != nil {
@@ -90,7 +90,7 @@
}
func TestWithoutRuntime(t *testing.T) {
- sh := modules.NewShell("withoutRuntime")
+ sh := modules.NewShell()
defer sh.Cleanup(os.Stderr, os.Stderr)
h, err := sh.Start("withoutRuntime", nil)
if err != nil {
diff --git a/services/mgmt/node/impl/impl_test.go b/services/mgmt/node/impl/impl_test.go
index 37b5bb9..1eab0bd 100644
--- a/services/mgmt/node/impl/impl_test.go
+++ b/services/mgmt/node/impl/impl_test.go
@@ -190,16 +190,10 @@
// args[0] is the entrypoint for the binary to be run from the shell script
// that SelfInstall will write out.
entrypoint := args[0]
- osenv := make([]string, 0, len(env))
- for k, v := range env {
- if k == modules.ShellEntryPoint {
- // Overwrite the entrypoint in our environment (i.e. the one
- // that got us here), with the one we want written out in the shell
- // script.
- v = entrypoint
- }
- osenv = append(osenv, k+"="+v)
- }
+ // Overwrite the entrypoint in our environment (i.e. the one
+ // that got us here), with the one we want written out in the shell
+ // script.
+ osenv := modules.SetEntryPoint(env, entrypoint)
if args[1] != "--" {
vlog.Fatalf("expected '--' immediately following command name")
}
diff --git a/services/mgmt/node/impl/util_test.go b/services/mgmt/node/impl/util_test.go
index 62dc931..0db0633 100644
--- a/services/mgmt/node/impl/util_test.go
+++ b/services/mgmt/node/impl/util_test.go
@@ -60,7 +60,7 @@
}
func createShellAndMountTable(t *testing.T) (*modules.Shell, func()) {
- sh := core.NewShell()
+ sh := modules.NewShell()
// The shell, will, by default share credentials with its children.
sh.ClearVar(consts.VeyronCredentials)
diff --git a/tools/naming/simulator/driver.go b/tools/naming/simulator/driver.go
index e27e4bb..9242830 100644
--- a/tools/naming/simulator/driver.go
+++ b/tools/naming/simulator/driver.go
@@ -21,7 +21,6 @@
"veyron.io/veyron/veyron/lib/expect"
"veyron.io/veyron/veyron/lib/flags/consts"
"veyron.io/veyron/veyron/lib/modules"
- "veyron.io/veyron/veyron/lib/modules/core"
_ "veyron.io/veyron/veyron/profiles"
)
@@ -101,7 +100,7 @@
// Subprocesses commands are run by fork/execing this binary
// so we must test to see if this instance is a subprocess or the
// the original command line instance.
- if os.Getenv(modules.ShellEntryPoint) != "" {
+ if modules.IsModulesProcess() {
// Subprocess, run the requested command.
if err := modules.Dispatch(); err != nil {
fmt.Fprintf(os.Stderr, "failed: %v\n", err)
@@ -116,8 +115,6 @@
shell.CreateAndUseNewCredentials()
}
- core.Install(shell)
-
scanner := bufio.NewScanner(os.Stdin)
lineno := 1
prompt(lineno)
diff --git a/tools/servicerunner/main.go b/tools/servicerunner/main.go
index 8620d14..00b00ff 100644
--- a/tools/servicerunner/main.go
+++ b/tools/servicerunner/main.go
@@ -14,7 +14,6 @@
"veyron.io/veyron/veyron/lib/expect"
"veyron.io/veyron/veyron/lib/flags/consts"
"veyron.io/veyron/veyron/lib/modules"
- "veyron.io/veyron/veyron/lib/modules/core"
_ "veyron.io/veyron/veyron/profiles"
)
@@ -57,9 +56,7 @@
func main() {
rt.Init()
- // NOTE(sadovsky): It would be better if Dispatch() itself performed the env
- // check.
- if os.Getenv(modules.ShellEntryPoint) != "" {
+ if modules.IsModulesProcess() {
panicOnError(modules.Dispatch())
return
}
@@ -78,9 +75,6 @@
}
vars[consts.VeyronCredentials] = v
}
- // NOTE(sadovsky): The following line will not be needed if the modules
- // library is restructured per my proposal.
- core.Install(sh)
h, err := sh.Start("root", nil, "--", "--veyron.tcp.address=127.0.0.1:0")
panicOnError(err)
