Merge pull request #204 from spiral/feature/hotreload

[wip] Hot-reloading capabilities - review wanted

6 files changed, 76 insertions, 5 deletions

diff --git a/server_config.go b/server_config.go
index 35965962..5fb4a014 100644
--- a/server_config.go
+++ b/server_config.go
@@ -8,15 +8,22 @@ import (
 	"os"
 	"os/exec"
 	"strings"
+	"sync"
 	"syscall"
 	"time"
 )
 
+// CommandProducer can produce commands.
+type CommandProducer func(cfg *ServerConfig) func() *exec.Cmd
+
 // ServerConfig config combines factory, pool and cmd configurations.
 type ServerConfig struct {
 	// Command includes command strings with all the parameters, example: "php worker.php pipes".
 	Command string
 
+	// CommandProducer overwrites
+	CommandProducer CommandProducer
+
 	// Relay defines connection method and factory to be used to connect to workers:
 	// "pipes", "tcp://:6001", "unix://rr.sock"
 	// This config section must not change on re-configuration.
@@ -31,7 +38,8 @@ type ServerConfig struct {
 	Pool *Config
 
 	// values defines set of values to be passed to the command context.
-	env []string
+	mu  sync.Mutex
+	env map[string]string
 }
 
 // InitDefaults sets missing values to their default values.
@@ -68,18 +76,42 @@ func (cfg *ServerConfig) Differs(new *ServerConfig) bool {
 
 // SetEnv sets new environment variable. Value is automatically uppercase-d.
 func (cfg *ServerConfig) SetEnv(k, v string) {
-	cfg.env = append(cfg.env, fmt.Sprintf("%s=%s", strings.ToUpper(k), v))
+	cfg.mu.Lock()
+	defer cfg.mu.Unlock()
+
+	if cfg.env == nil {
+		cfg.env = make(map[string]string)
+	}
+
+	cfg.env[k] = v
+}
+
+// GetEnv must return list of env variables.
+func (cfg *ServerConfig) GetEnv() (env []string) {
+	env = append(os.Environ(), fmt.Sprintf("RR_RELAY=%s", cfg.Relay))
+	for k, v := range cfg.env {
+		env = append(env, fmt.Sprintf("%s=%s", strings.ToUpper(k), v))
+	}
+
+	return
 }
 
 // makeCommands returns new command provider based on configured options.
 func (cfg *ServerConfig) makeCommand() func() *exec.Cmd {
+	cfg.mu.Lock()
+	defer cfg.mu.Unlock()
+
+	if cfg.CommandProducer != nil {
+		return cfg.CommandProducer(cfg)
+	}
+
 	var cmd = strings.Split(cfg.Command, " ")
 	return func() *exec.Cmd {
 		cmd := exec.Command(cmd[0], cmd[1:]...)
 		osutil.IsolateProcess(cmd)
 
-		cmd.Env = append(os.Environ(), fmt.Sprintf("RR_RELAY=%s", cfg.Relay))
-		cmd.Env = append(cmd.Env, cfg.env...)
+		cmd.Env = cfg.GetEnv()
+
 		return cmd
 	}
 }
diff --git a/service/container.go b/service/container.go
index a21b49b4..0be4f853 100644
--- a/service/container.go
+++ b/service/container.go
@@ -46,6 +46,9 @@ type Container interface {
 
 	// Close all active services.
 	Stop()
+
+	// List service names.
+	List() []string
 }
 
 // Config provides ability to slice configuration sections and unmarshal configuration data into
@@ -212,6 +215,16 @@ func (c *container) Stop() {
 	}
 }
 
+// List all service names.
+func (c *container) List() []string {
+	names := make([]string, 0, len(c.services))
+	for _, e := range c.services {
+		names = append(names, e.name)
+	}
+
+	return names
+}
+
 // calls Init method with automatically resolved arguments.
 func (c *container) initService(s interface{}, segment Config) (bool, error) {
 	r := reflect.TypeOf(s)
diff --git a/service/container_test.go b/service/container_test.go
index 8fcaede2..4628986a 100644
--- a/service/container_test.go
+++ b/service/container_test.go
@@ -129,6 +129,20 @@ func TestContainer_Has(t *testing.T) {
 	assert.False(t, c.Has("another"))
 }
 
+func TestContainer_List(t *testing.T) {
+	logger, hook := test.NewNullLogger()
+	logger.SetLevel(logrus.DebugLevel)
+
+	c := NewContainer(logger)
+	c.Register("test", &testService{})
+
+	assert.Equal(t, 0, len(hook.Entries))
+	assert.Equal(t, 1, len(c.List()))
+
+	assert.True(t, c.Has("test"))
+	assert.False(t, c.Has("another"))
+}
+
 func TestContainer_Get(t *testing.T) {
 	logger, hook := test.NewNullLogger()
 	logger.SetLevel(logrus.DebugLevel)
diff --git a/service/http/service.go b/service/http/service.go
index 58038acb..945a12c4 100644
--- a/service/http/service.go
+++ b/service/http/service.go
@@ -31,6 +31,7 @@ type middleware func(f http.HandlerFunc) http.HandlerFunc
 // Service manages rr, http servers.
 type Service struct {
 	cfg        *Config
+	cprod      roadrunner.CommandProducer
 	env        env.Environment
 	lsns       []func(event int, ctx interface{})
 	mdwr       []middleware
@@ -48,6 +49,11 @@ func (s *Service) Attach(w roadrunner.Controller) {
 	s.controller = w
 }
 
+// ProduceCommands changes the default command generator method
+func (s *Service) ProduceCommands(producer roadrunner.CommandProducer) {
+	s.cprod = producer
+}
+
 // AddMiddleware adds new net/http mdwr.
 func (s *Service) AddMiddleware(m middleware) {
 	s.mdwr = append(s.mdwr, m)
@@ -87,6 +93,7 @@ func (s *Service) Serve() error {
 		}
 	}
 
+	s.cfg.Workers.CommandProducer = s.cprod
 	s.cfg.Workers.SetEnv("RR_HTTP", "true")
 
 	s.rr = roadrunner.NewServer(s.cfg.Workers)
diff --git a/service/metrics/rpc_test.go b/service/metrics/rpc_test.go
index 6d061f1d..136f031c 100644
--- a/service/metrics/rpc_test.go
+++ b/service/metrics/rpc_test.go
@@ -43,10 +43,13 @@ func setup(t *testing.T, metric string, portNum string) (*rpc2.Client, service.C
 	assert.True(t, s.(*Service).Enabled())
 
 	go func() { c.Serve() }()
-	time.Sleep(time.Millisecond * 100)
+	time.Sleep(time.Millisecond * 200)
 
 	client, err := rs.Client()
 	assert.NoError(t, err)
+	if err != nil {
+		panic(err)
+	}
 
 	return client, c
 }
diff --git a/service/metrics/service.go b/service/metrics/service.go
index 4916b3e0..b581f041 100644
--- a/service/metrics/service.go
+++ b/service/metrics/service.go
@@ -1,5 +1,7 @@
 package metrics
 
+// todo: declare metric at runtime
+
 import (
 	"context"
 	"github.com/prometheus/client_golang/prometheus"