graceful shutdown, CoreInterface changes, MongoDB official driver is the only DB backend

core/base/base.go

@@ -1,153 +0,0 @@
-package base
-
-import (
-	"fmt"
-
-	"github.com/globalsign/mgo"
-	"github.com/jinzhu/gorm"
-)
-
-type Base struct{}
-
-func (b *Base) Register() (string, error) {
-	if e := b.BeforeLoadPlugins(); e != nil {
-		return "", e
-	}
-	if e := b.LoadPlugins(); e != nil {
-		return "", e
-	}
-	if e := b.AfterLoadPlugins(); e != nil {
-		return "", e
-	}
-	if e := b.BeforeLoadConfiguration(); e != nil {
-		return "", e
-	}
-	if e := b.LoadConfiguration(); e != nil {
-		return "", e
-	}
-	if e := b.AfterLoadConfiguration(); e != nil {
-		return "", e
-	}
-	if e := b.BeforeConnectToDatabases(); e != nil {
-		return "", e
-	}
-	if e := b.ConnectToDatabases(); e != nil {
-		return "", e
-	}
-	if e := b.AfterConnectToDatabases(); e != nil {
-		return "", e
-	}
-	if e := b.BeforeSetupLogger(); e != nil {
-		return "", e
-	}
-	if e := b.SetupLogger(); e != nil {
-		return "", e
-	}
-	if e := b.AfterSetupLogger(); e != nil {
-		return "", e
-	}
-	if e := b.BeforeSetupRoutes(); e != nil {
-		return "", e
-	}
-	if e := b.SetupRoutes(); e != nil {
-		return "", e
-	}
-	if e := b.AfterSetupRoutes(); e != nil {
-		return "", e
-	}
-	if e := b.BeforeRun(); e != nil {
-		return "", e
-	}
-	if e := b.Run(); e != nil {
-		return "", e
-	}
-	if e := b.AfterRun(); e != nil {
-		return "", e
-	}
-	return "base", nil
-}
-
-func (b *Base) UnRegister() error {
-	return nil
-}
-
-func (b *Base) BeforeLoadPlugins() error {
-	fmt.Println("Hello World. BeforeLoadPlugins")
-	return nil
-}
-
-func (b *Base) LoadPlugins() error {
-	return nil
-}
-
-func (b *Base) AfterLoadPlugins() error {
-	return nil
-}
-
-func (b *Base) BeforeLoadConfiguration() error {
-	return nil
-}
-
-func (b *Base) LoadConfiguration() error {
-	return nil
-}
-
-func (b *Base) AfterLoadConfiguration() error {
-	return nil
-}
-
-func (b *Base) ConnectMongoDB(string) (*mgo.Session, error) {
-	return nil, nil
-}
-
-func (b *Base) ConnectGORM(string) (*gorm.DB, error) {
-	return nil, nil
-}
-
-func (b *Base) BeforeConnectToDatabases() error {
-	return nil
-}
-
-func (b *Base) ConnectToDatabases() error {
-	return nil
-}
-
-func (b *Base) AfterConnectToDatabases() error {
-	return nil
-}
-
-func (b *Base) BeforeSetupLogger() error {
-	return nil
-}
-
-func (b *Base) SetupLogger() error {
-	return nil
-}
-
-func (b *Base) AfterSetupLogger() error {
-	return nil
-}
-
-func (b *Base) BeforeSetupRoutes() error {
-	return nil
-}
-
-func (b *Base) SetupRoutes() error {
-	return nil
-}
-
-func (b *Base) AfterSetupRoutes() error {
-	return nil
-}
-
-func (b *Base) BeforeRun() error {
-	return nil
-}
-
-func (b *Base) Run() error {
-	return nil
-}
-
-func (b *Base) AfterRun() error {
-	return nil
-}

core/core.go

@@ -0,0 +1,198 @@
+package core
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"time"
+
+	"go.mongodb.org/mongo-driver/mongo"
+	"go.mongodb.org/mongo-driver/mongo/options"
+)
+
+type Core struct {
+	client        *mongo.Client
+	clientContext context.Context
+	clientTimeout time.Duration
+	clientURI     string
+}
+
+func (c *Core) Register() (string, error) {
+	if e := c.BeforeLoadPlugins(); e != nil {
+		return "", e
+	}
+	if e := c.LoadPlugins(); e != nil {
+		return "", e
+	}
+	if e := c.AfterLoadPlugins(); e != nil {
+		return "", e
+	}
+	if e := c.BeforeLoadConfiguration(); e != nil {
+		return "", e
+	}
+	if e := c.LoadConfiguration(); e != nil {
+		return "", e
+	}
+	if e := c.AfterLoadConfiguration(); e != nil {
+		return "", e
+	}
+	if e := c.BeforeDatabaseInit(); e != nil {
+		return "", e
+	}
+	if e := c.DatabaseInit(); e != nil {
+		return "", e
+	}
+	if e := c.AfterDatabaseInit(); e != nil {
+		return "", e
+	}
+	if e := c.BeforeSetupLogger(); e != nil {
+		return "", e
+	}
+	if e := c.SetupLogger(); e != nil {
+		return "", e
+	}
+	if e := c.AfterSetupLogger(); e != nil {
+		return "", e
+	}
+	if e := c.BeforeSetupRoutes(); e != nil {
+		return "", e
+	}
+	if e := c.SetupRoutes(); e != nil {
+		return "", e
+	}
+	if e := c.AfterSetupRoutes(); e != nil {
+		return "", e
+	}
+	return "core", nil
+}
+
+func (c *Core) UnRegister() error {
+	fmt.Println("Core: UnRegister")
+	if e := c.BeforeShutdown(); e != nil {
+		return e
+	}
+	if e := c.Shutdown(); e != nil {
+		return e
+	}
+	return nil
+}
+
+func (c *Core) BeforeLoadPlugins() error {
+	fmt.Println("Core: BeforeLoadPlugins")
+	return nil
+}
+
+func (c *Core) LoadPlugins() error {
+	fmt.Println("Core: LoadPlugins")
+	return nil
+}
+
+func (c *Core) AfterLoadPlugins() error {
+	fmt.Println("Core: AfterLoadPlugins")
+	return nil
+}
+
+func (c *Core) BeforeLoadConfiguration() error {
+	fmt.Println("Core: BeforeLoadConfiguration")
+	return nil
+}
+
+func (c *Core) LoadConfiguration() error {
+	fmt.Println("Core: LoadConfiguration")
+	c.clientURI = "mongodb://localhost:27017/"
+	return nil
+}
+
+func (c *Core) AfterLoadConfiguration() error {
+	fmt.Println("Core: AfterLoadConfiguration")
+	return nil
+}
+
+func (c *Core) BeforeDatabaseInit() error {
+	fmt.Println("Core: BeforeDatabaseInit")
+	return nil
+}
+
+func (c *Core) DatabaseInit() error {
+	fmt.Println("Core: DatabaseInit")
+	c.clientTimeout = 10 * time.Second
+	c.clientContext = context.Background()
+	var e error
+	c.client, e = mongo.NewClient(options.Client().ApplyURI(c.clientURI))
+	if e != nil {
+		return e
+	}
+	ctx, cancel := context.WithTimeout(c.clientContext, c.clientTimeout)
+	defer cancel()
+	return c.client.Connect(ctx)
+}
+
+func (c *Core) AfterDatabaseInit() error {
+	fmt.Println("Core: AfterDatabaseInit")
+	return nil
+}
+
+func (c *Core) BeforeSetupLogger() error {
+	fmt.Println("Core: BeforeSetupLogger")
+	return nil
+}
+
+func (c *Core) SetupLogger() error {
+	fmt.Println("Core: SetupLogger")
+	return nil
+}
+
+func (c *Core) AfterSetupLogger() error {
+	fmt.Println("Core: AfterSetupLogger")
+	return nil
+}
+
+func (c *Core) BeforeSetupRoutes() error {
+	fmt.Println("Core: BeforeSetupRoutes")
+	return nil
+}
+
+func (c *Core) SetupRoutes() error {
+	fmt.Println("Core: SetupRoutes")
+	return nil
+}
+
+func (c *Core) AfterSetupRoutes() error {
+	fmt.Println("Core: AfterSetupRoutes")
+	return nil
+}
+
+func (c *Core) BeforeRun() error {
+	fmt.Println("Core: BeforeRun")
+	return nil
+}
+
+func (c *Core) Run() error {
+	fmt.Println("Core: Run")
+	return http.ListenAndServe(":8080", nil)
+}
+
+func (c *Core) AfterRun() error {
+	fmt.Println("Core: AfterRun")
+	return nil
+}
+
+func (c *Core) BeforeShutdown() error {
+	fmt.Println("Core: BeforeShutdown")
+	return nil
+}
+
+func (c *Core) Shutdown() error {
+	fmt.Println("Core: Shutdown")
+	return c.Close()
+}
+
+func (c *Core) Client() *mongo.Client {
+	fmt.Println("Core: Client")
+	return c.client
+}
+
+func (c *Core) Close() error {
+	fmt.Println("Core: Close")
+	return c.client.Disconnect(c.clientContext)
+}

go.mod

@@ -0,0 +1,9 @@
+module git.icod.de/dalu/contentplatform
+
+go 1.14
+
+require (
+	github.com/davecgh/go-spew v1.1.1
+	go.mongodb.org/mongo-driver v1.3.3
+	golang.org/x/crypto v0.0.0-20191205180655-e7c4368fe9dd // indirect
+)

interfaces.go

@@ -1,9 +1,6 @@
 package main
 
-import (
+import "go.mongodb.org/mongo-driver/mongo"
-	"github.com/globalsign/mgo"
-	"github.com/jinzhu/gorm"
-)
 
 type CoreInterface interface {
 	Register() (string, error)
@@ -17,20 +14,9 @@ type CoreInterface interface {
 	LoadConfiguration() error
 	AfterLoadConfiguration() error
 
-	// connection string parameter e.g. "localhost"
+	BeforeDatabaseInit() error
-	ConnectMongoDB(string) (*mgo.Session, error)
+	DatabaseInit() error
-
+	AfterDatabaseInit() error
-	// connection string parameter
-	ConnectGORM(string) (*gorm.DB, error)
-
-	// ConnectNeo4j
-	// ConnectArangoDB
-	// ConnectCassandra
-	// ConnectDGraph
-
-	BeforeConnectToDatabases() error
-	ConnectToDatabases() error
-	AfterConnectToDatabases() error
 
 	BeforeSetupLogger() error
 	SetupLogger() error
@@ -43,6 +29,14 @@ type CoreInterface interface {
 	BeforeRun() error
 	Run() error
 	AfterRun() error
+
+	BeforeShutdown() error
+	Shutdown() error
+}
+
+type DatabaseInterface interface {
+	Client() *mongo.Client
+	Close() error
 }
 
 type HandlerInterface interface {

main.go

@@ -2,16 +2,33 @@ package main
 
 import (
 	"log"
+	"os"
+	"os/signal"
+	"syscall"
 
-	"git.icod.de/dalu/contentplatform/core/base"
+	"git.icod.de/dalu/contentplatform/core"
 )
 
 var registry = NewPluginRegistry()
 
 func main() {
-
+	catchSignal()
-	if e := registry.RegisterCorePlugin(new(base.Base)); e != nil {
+	corePlugin := new(core.Core)
+	if e := registry.RegisterCorePlugin(corePlugin); e != nil {
 		log.Fatal(e.Error())
 	}
-
+	if e := registry.Run(); e != nil {
+		log.Fatal(e.Error())
+	}
+}
+
+func catchSignal() {
+	sigc := make(chan os.Signal, 1)
+	signal.Notify(sigc, os.Interrupt, os.Kill, syscall.SIGTERM)
+	go func(c chan os.Signal) {
+		sig := <-c
+		log.Printf("Caught signal %s: shutting down.", sig)
+		registry.Shutdown()
+		os.Exit(0)
+	}(sigc)
 }

registry.go

@@ -1,5 +1,10 @@
 package main
 
+import (
+	"fmt"
+	"github.com/davecgh/go-spew/spew"
+)
+
 type PluginRegistry struct {
 	CorePlugin    map[string]CoreInterface
 	HandlerPlugin map[string]HandlerInterface
@@ -13,6 +18,7 @@ func NewPluginRegistry() *PluginRegistry {
 }
 
 func (r *PluginRegistry) RegisterCorePlugin(plugin CoreInterface) error {
+	spew.Dump(plugin)
 	name, e := plugin.Register()
 	if e != nil {
 		return e
@@ -45,3 +51,34 @@ func (r *PluginRegistry) RemoveCorePlugin(name string) {
 func (r *PluginRegistry) RemoveHandlerPlugin(name string) {
 	delete(r.HandlerPlugin, name)
 }
+
+func (r *PluginRegistry) Run() error {
+	for _, v := range r.CorePlugin {
+		if e := v.BeforeRun(); e != nil {
+			return e
+		}
+	}
+	for _, v := range r.CorePlugin {
+		if e := v.Run(); e != nil {
+			return e
+		}
+	}
+	for _, v := range r.CorePlugin {
+		if e := v.AfterRun(); e != nil {
+			return e
+		}
+	}
+	return nil
+}
+
+func (r *PluginRegistry) Shutdown() {
+	fmt.Println("Registry: Shutdown")
+	spew.Dump(r.CorePlugin)
+	for k, v := range r.CorePlugin {
+		fmt.Println(k, v)
+		if e := v.UnRegister(); e != nil {
+			panic(e)
+		}
+	}
+	fmt.Println("Registry: Shutdown Done")
+}