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-rw-r--r--_old/container.go371
1 files changed, 0 insertions, 371 deletions
diff --git a/_old/container.go b/_old/container.go
deleted file mode 100644
index daab7339..00000000
--- a/_old/container.go
+++ /dev/null
@@ -1,371 +0,0 @@
-package _old
-
-import (
- "fmt"
- "github.com/pkg/errors"
- "github.com/sirupsen/logrus"
- "reflect"
- "sync"
-)
-
-var errNoConfig = fmt.Errorf("no config has been provided")
-var errTempFix223 = fmt.Errorf("temporary error for fix #223") // meant no error here, just shutdown the server
-
-// InitMethod contains name of the method to be automatically invoked while service initialization. Must return
-// (bool, error). Container can be requested as well. Config can be requested in a form
-// of service.Config or pointer to service specific config struct (automatically unmarshalled), config argument must
-// implement service.HydrateConfig.
-const InitMethod = "Init"
-
-// Service can serve. Services can provide Init method which must return (bool, error) signature and might accept
-// other services and/or configs as dependency.
-type Service interface {
- // Serve serves.
- Serve() error
-
- // Detach stops the service.
- Stop()
-}
-
-// Container controls all internal RR services and provides plugin based system.
-type Container interface {
- // Register add new service to the container under given name.
- Register(name string, service interface{})
-
- // Reconfigure configures all underlying services with given configuration.
- Init(cfg Config) error
-
- // Check if svc has been registered.
- Has(service string) bool
-
- // get returns svc instance by it's name or nil if svc not found. Method returns current service status
- // as second value.
- Get(service string) (svc interface{}, status int)
-
- // Serve all configured services. Non blocking.
- Serve() error
-
- // Close all active services.
- Stop()
-
- // List service names.
- List() []string
-}
-
-// Config provides ability to slice configuration sections and unmarshal configuration data into
-// given structure.
-type Config interface {
- // get nested config section (sub-map), returns nil if section not found.
- Get(service string) Config
-
- // Unmarshal unmarshal config data into given struct.
- Unmarshal(out interface{}) error
-}
-
-// HydrateConfig provides ability to automatically hydrate config with values using
-// service.Config as the source.
-type HydrateConfig interface {
- // Hydrate must populate config values using given config source.
- // Must return error if config is not valid.
- Hydrate(cfg Config) error
-}
-
-// DefaultsConfig declares ability to be initated without config data provided.
-type DefaultsConfig interface {
- // InitDefaults allows to init blank config with pre-defined set of default values.
- InitDefaults() error
-}
-
-type container struct {
- log logrus.FieldLogger
- mu sync.Mutex
- services []*entry
- errc chan struct {
- name string
- err error
- }
-}
-
-// NewContainer creates new service container.
-func NewContainer(log logrus.FieldLogger) Container {
- return &container{
- log: log,
- services: make([]*entry, 0),
- errc: make(chan struct {
- name string
- err error
- }, 1),
- }
-}
-
-// Register add new service to the container under given name.
-func (c *container) Register(name string, service interface{}) {
- c.mu.Lock()
- defer c.mu.Unlock()
-
- c.services = append(c.services, &entry{
- name: name,
- svc: service,
- status: StatusInactive,
- })
-}
-
-// Check hasStatus svc has been registered.
-func (c *container) Has(target string) bool {
- c.mu.Lock()
- defer c.mu.Unlock()
-
- for _, e := range c.services {
- if e.name == target {
- return true
- }
- }
-
- return false
-}
-
-// get returns svc instance by it's name or nil if svc not found.
-func (c *container) Get(target string) (svc interface{}, status int) {
- c.mu.Lock()
- defer c.mu.Unlock()
-
- for _, e := range c.services {
- if e.name == target {
- return e.svc, e.getStatus()
- }
- }
-
- return nil, StatusUndefined
-}
-
-// Init configures all underlying services with given configuration.
-func (c *container) Init(cfg Config) error {
- for _, e := range c.services {
- if e.getStatus() >= StatusOK {
- return fmt.Errorf("service [%s] has already been configured", e.name)
- }
-
- // inject service dependencies
- if ok, err := c.initService(e.svc, cfg.Get(e.name)); err != nil {
- // soft error (skipping)
- if err == errNoConfig {
- c.log.Debugf("[%s]: disabled", e.name)
- continue
- }
-
- return errors.Wrap(err, fmt.Sprintf("[%s]", e.name))
- } else if ok {
- e.setStatus(StatusOK)
- } else {
- c.log.Debugf("[%s]: disabled", e.name)
- }
- }
-
- return nil
-}
-
-// Serve all configured services. Non blocking.
-func (c *container) Serve() error {
- var running = 0
- for _, e := range c.services {
- if e.hasStatus(StatusOK) && e.canServe() {
- running++
- c.log.Debugf("[%s]: started", e.name)
- go func(e *entry) {
- e.setStatus(StatusServing)
- defer e.setStatus(StatusStopped)
- if err := e.svc.(Service).Serve(); err != nil {
- c.errc <- struct {
- name string
- err error
- }{name: e.name, err: errors.Wrap(err, fmt.Sprintf("[%s]", e.name))}
- } else {
- c.errc <- struct {
- name string
- err error
- }{name: e.name, err: errTempFix223}
- }
- }(e)
- }
- }
-
- // simple handler to handle empty configs
- if running == 0 {
- return nil
- }
-
- for fail := range c.errc {
- if fail.err == errTempFix223 {
- // if we call stop, then stop all plugins
- break
- } else {
- c.log.Errorf("[%s]: %s", fail.name, fail.err)
- c.Stop()
- return fail.err
- }
- }
-
- return nil
-}
-
-// Detach sends stop command to all running services.
-func (c *container) Stop() {
- for _, e := range c.services {
- if e.hasStatus(StatusServing) {
- e.setStatus(StatusStopping)
- e.svc.(Service).Stop()
- e.setStatus(StatusStopped)
-
- c.log.Debugf("[%s]: stopped", e.name)
- }
- }
-}
-
-// 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)
-
- m, ok := r.MethodByName(InitMethod)
- if !ok {
- // no Init method is presented, assuming service does not need initialization.
- return true, nil
- }
-
- if err := c.verifySignature(m); err != nil {
- return false, err
- }
-
- // hydrating
- values, err := c.resolveValues(s, m, segment)
- if err != nil {
- return false, err
- }
-
- // initiating service
- out := m.Func.Call(values)
-
- if out[1].IsNil() {
- return out[0].Bool(), nil
- }
-
- return out[0].Bool(), out[1].Interface().(error)
-}
-
-// resolveValues returns slice of call arguments for service Init method.
-func (c *container) resolveValues(s interface{}, m reflect.Method, cfg Config) (values []reflect.Value, err error) {
- for i := 0; i < m.Type.NumIn(); i++ {
- v := m.Type.In(i)
-
- switch {
- case v.ConvertibleTo(reflect.ValueOf(s).Type()): // service itself
- values = append(values, reflect.ValueOf(s))
-
- case v.Implements(reflect.TypeOf((*Container)(nil)).Elem()): // container
- values = append(values, reflect.ValueOf(c))
-
- case v.Implements(reflect.TypeOf((*logrus.StdLogger)(nil)).Elem()),
- v.Implements(reflect.TypeOf((*logrus.FieldLogger)(nil)).Elem()),
- v.ConvertibleTo(reflect.ValueOf(c.log).Type()): // logger
- values = append(values, reflect.ValueOf(c.log))
-
- case v.Implements(reflect.TypeOf((*HydrateConfig)(nil)).Elem()): // injectable config
- sc := reflect.New(v.Elem())
-
- if dsc, ok := sc.Interface().(DefaultsConfig); ok {
- err := dsc.InitDefaults()
- if err != nil {
- return nil, err
- }
- if cfg == nil {
- values = append(values, sc)
- continue
- }
-
- } else if cfg == nil {
- return nil, errNoConfig
- }
-
- if err := sc.Interface().(HydrateConfig).Hydrate(cfg); err != nil {
- return nil, err
- }
-
- values = append(values, sc)
-
- case v.Implements(reflect.TypeOf((*Config)(nil)).Elem()): // generic config section
- if cfg == nil {
- return nil, errNoConfig
- }
-
- values = append(values, reflect.ValueOf(cfg))
-
- default: // dependency on other service (resolution to nil if service can't be found)
- value, err := c.resolveValue(v)
- if err != nil {
- return nil, err
- }
-
- values = append(values, value)
- }
- }
-
- return
-}
-
-// verifySignature checks if Init method has valid signature
-func (c *container) verifySignature(m reflect.Method) error {
- if m.Type.NumOut() != 2 {
- return fmt.Errorf("method Init must have exact 2 return values")
- }
-
- if m.Type.Out(0).Kind() != reflect.Bool {
- return fmt.Errorf("first return value of Init method must be bool type")
- }
-
- if !m.Type.Out(1).Implements(reflect.TypeOf((*error)(nil)).Elem()) {
- return fmt.Errorf("second return value of Init method value must be error type")
- }
-
- return nil
-}
-
-func (c *container) resolveValue(v reflect.Type) (reflect.Value, error) {
- value := reflect.Value{}
- for _, e := range c.services {
- if !e.hasStatus(StatusOK) {
- continue
- }
-
- if v.Kind() == reflect.Interface && reflect.TypeOf(e.svc).Implements(v) {
- if value.IsValid() {
- return value, fmt.Errorf("disambiguous dependency `%s`", v)
- }
-
- value = reflect.ValueOf(e.svc)
- }
-
- if v.ConvertibleTo(reflect.ValueOf(e.svc).Type()) {
- if value.IsValid() {
- return value, fmt.Errorf("disambiguous dependency `%s`", v)
- }
-
- value = reflect.ValueOf(e.svc)
- }
- }
-
- if !value.IsValid() {
- // placeholder (make sure to check inside the method)
- value = reflect.New(v).Elem()
- }
-
- return value, nil
-}