api/database/mongodb/db.go

package mongodb

import (
	"fmt"
	"github.com/globalsign/mgo/bson"
	"time"

	"git.aiterp.net/rpdata/api/internal/config"
	"git.aiterp.net/rpdata/api/repositories"
	"github.com/globalsign/mgo"
)

// Init initializes the mongodb database
func Init(cfg config.Database) (bundle *repositories.Bundle, closeFn func() error, err error) {
	port := cfg.Port
	if port <= 0 {
		port = 27017
	}

	session, err := mgo.DialWithInfo(&mgo.DialInfo{
		Addrs:     []string{fmt.Sprintf("%s:%d", cfg.Host, port)},
		Timeout:   30 * time.Second,
		Database:  cfg.Db,
		Username:  cfg.Username,
		Password:  cfg.Password,
		Mechanism: cfg.Mechanism,
		Source:    cfg.Db,
	})
	if err != nil {
		return
	}

	db := session.DB(cfg.Db)

	characters, err := newCharacterRepository(db)
	if err != nil {
		session.Close()
		return nil, nil, err
	}

	bundle = &repositories.Bundle{
		Characters: characters,
		Tags:       newTagRepository(db),
	}

	closeFn = func() error {
		session.Close()
		return nil
	}

	return
}

type counter struct {
	coll     *mgo.Collection
	category string
	name     string
}

func newCounter(db *mgo.Database, category, name string) *counter {
	return &counter{
		coll:     db.C("core.counters"),
		category: category,
		name:     name,
	}
}

func (c *counter) WithName(name string) *counter {
	return &counter{
		coll:     c.coll,
		category: c.category,
		name:     name,
	}
}

func (c *counter) Increment(amount int) (int, error) {
	type counterDoc struct {
		ID    string `bson:"_id"`
		Value int    `bson:"value"`
	}

	id := c.category + "." + c.name
	doc := counterDoc{}

	_, err := c.coll.Find(bson.M{"_id": id}).Apply(mgo.Change{
		Update:    bson.M{"$inc": bson.M{"value": amount}},
		Upsert:    true,
		ReturnNew: true,
	}, &doc)
	if err != nil {
		return -1, err
	}

	return doc.Value, nil
}