feat: use mongodb official driver instead of mgo (#1782)

* wip: backup

* wip: backup

* wip: backup

* backup

* backup

* backup

* add more tests

* fix wrong dependency

* fix lint errors

* remove test due to data race

* add tests

* fix test error

* add mon.Model

* add mon.Model unmarshal

* add monc

* add more tests for monc

* add more tests for monc

* add docs for mon and monc packages

* fix doc errors

* chhore: add comment

* chore: fix test bug

* chore: refine tests

* chore: remove primitive.NewObjectID in test code

* chore: rename test files for typo

core/stores/mon/clientmanager.go

@@ -0,0 +1,51 @@
+package mon
+
+import (
+	"context"
+	"io"
+	"time"
+
+	"github.com/zeromicro/go-zero/core/syncx"
+	"go.mongodb.org/mongo-driver/mongo"
+	mopt "go.mongodb.org/mongo-driver/mongo/options"
+)
+
+const defaultTimeout = time.Second
+
+var clientManager = syncx.NewResourceManager()
+
+// ClosableClient wraps *mongo.Client and provides a Close method.
+type ClosableClient struct {
+	*mongo.Client
+}
+
+// Close disconnects the underlying *mongo.Client.
+func (cs *ClosableClient) Close() error {
+	return cs.Client.Disconnect(context.Background())
+}
+
+// Inject injects a *mongo.Client into the client manager.
+// Typically, this is used to inject a *mongo.Client for test purpose.
+func Inject(key string, client *mongo.Client) {
+	clientManager.Inject(key, &ClosableClient{client})
+}
+
+func getClient(url string) (*mongo.Client, error) {
+	val, err := clientManager.GetResource(url, func() (io.Closer, error) {
+		cli, err := mongo.Connect(context.Background(), mopt.Client().ApplyURI(url))
+		if err != nil {
+			return nil, err
+		}
+
+		concurrentSess := &ClosableClient{
+			Client: cli,
+		}
+
+		return concurrentSess, nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return val.(*ClosableClient).Client, nil
+}