db

Go-Express

Simple Mongo client for Go. The package aims to match Express seamless integration with NodeJs and MongoDb.

Index

Requirements

• MongoDb (access to a server)
• Mgo

Dependencies

(GoDeps supported as well.) Manually:

	go get github.com/asaskevich/govalidator
	go get gopkg.in/mgo.v2

install

go get github.com/cheikhshift/db

Import

import (
	"log" //optional
	"github.com/cheikhshift/db"
)

Connect

The snippet below will connect to your database @ your localhost

dbs,err := db.Connect("localhost","database") 
if err != nil {
	log.Fatal(err)
}

Format of server URI :

[mongodb://][user:pass@]host1[:port1][,host2[:port2],...][/database][?options]

Add new model

Define a new struct as usual (fields Created and Id are system generated) :

type MyObject struct {
	Id bson.ObjectId `bson:"_id,omitempty"`
	TestField string `valid:"unique"`
	FieldTwo string `valid:"email,required"`
	Created time.Time //timestamp local format
}

The following tag will ensure no duplicates happen while saving.

TestField string `valid:"unique"`

The following tag valid will ensure your field data is an email.

 FieldTwo string `valid:"email,required"`

Save a model

obj := NewObject{FieldTwo: "value" }
dbs.New(&obj)	
err = dbs.Save(&obj)
if err != nil {
	log.Fatal(err)
}

Retrieve model

The following query will return one object. Within the Find function you may use all of the usual Mongo DB query functions. Remember to add strings even around $ prefixed parameters. The following example will retrieve one result. Any struct field is converted to lower case on database save, when performing a query type struct field names without capital letters.

query := MyObject{}
dbs.Q(query).Find(db.O{"fieldtwo":"value"}).One(&query)

fmt.Println(query)

Delete model

This function will fail if your struct's Id field is blank.

obj := NewObject{FieldTwo: "value" }
err := dbs.Add(&obj)	
if err != nil {
	log.Fatal(err)
}


dbs.Remove(&obj)

#Index

package github.com/cheikhshift/db

Structs

DB

type DB struct {
	MoDb *mgo.Database
}

O

type O bson.M

Functions

Connect

Create a new database connection.

func Connect(url string, db string) (DB,error)

-url : MongoDb server URI to connect to.

• db: database to use.

Close

Close database connection.

func (d DB) Close()

Validate

Verify if model is valid. This package is used for validation, Read more about supported types here.

func (d DB) PreVerify(item interface{}) error

• item : Model (struct) to verify.

Query

More information about mgo.Query here. Once your query is retrieved you may count ,limit, skip as you please.

func (d DB) Query(item interface{}, query interface{}) *mgo.Query

• item : Model to set query to.
• query : db.O map of parameters to query.

Add

Add the specified models to your database.

func (d DB) Add(items ...interface{}) error {

• items : models to save.

Save

Update the model.

func (d DB) Save(item interface{}) error

• item : model to update.

Remove

Remove model from database. If the model has no value for field Id this function will fail.

func (d DB) Remove(items ...interface{}) error 

• items : items to remove.

RemoveAll

Remove items via db.O query.

func (d DB) RemoveAll(item interface{},query  interface{}) (*mgo.ChangeInfo,error)

• item : model to set query to.
• query : map of parameters to query.

UpdateAll ...Save All

Update models in your database via query.

func (d DB) UpdateAll(item interface{},query interface{}, update interface{}) (*mgo.ChangeInfo,error) 

• item : model to set query to.
• query : map of parameters to query.
• update : map of updates to make. Remember to use MongoDb selections , ie : $ne.