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Casbah & Rogue for MongoDB - Query Features

I am currently using Casbah with MongoDB to implement a web service. I have no problems so far. I am using Scala.

However, I was just curious to find out if there is anything better than Casbah to do many queries like find / findOne.

I came across Rogue, based on the Scala DSL type, which says the query will be simpler and more understandable.

So, I wanted to know if it’s useful to switch to Rogue, as the web services project is becoming more complex and can help get Rogue support for queries?

I just wanted to know if I should continue or move on to something better.

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Rogue Lift MongoDB-Record.

, , , , Lift-Record. " ", . Lift-Record + Rogue, - Scala. Lift Rogue, , , . Lift-Record MongoDB:

object LiftRecordDemo extends Application {
  // We'll use enums for Type and Subtype
  object EventType extends Enumeration {
    type EventType = Value
    val Conference, Webinar = Value
  }

  object EventSubType extends Enumeration {
    type EventSubType = Value
    val FullDay = Value("Full Day")
    val HalfDay = Value("Half Day")
  }



  class MongoEvent extends MongoRecord[MongoEvent] with MongoId[MongoEvent] {
    def meta = MongoEvent

    object name extends StringField(this, 255)
    object eventType extends EnumField(this, EventType) 
    object eventSubType extends OptionalEnumField(this, EventSubType)
    object location extends JsonObjectField[MongoEvent, EventLocation](this, EventLocation)  {
      def defaultValue = EventLocation(None, None, None, None, None, None, None)
    }

    object hashtag extends OptionalStringField(this, 32)
    object language extends OptionalStringField(this, 32)
    object date extends JsonObjectField[MongoEvent, EventDate](this, EventDate) {
      def defaultValue = EventDate(new DateTime, None)
    }

    object url extends OptionalStringField(this, 255)
    object presenter extends OptionalStringField(this, 255)

  }

  object MongoEvent extends MongoEvent with MongoMetaRecord[MongoEvent] {
    override def collectionName = "mongoEvents"
    override def formats = super.formats + new EnumSerializer(EventType) + new EnumSerializer(EventSubType)
  }


  case class EventLocation(val venueName: Option[String], val url: Option[String], val address: Option[String], val city: Option[String], val state: Option[String], val zip: Option[String], val country: Option[String]) extends JsonObject[EventLocation] {
    def meta = EventLocation
  }

  object EventLocation extends JsonObjectMeta[EventLocation]

  case class EventDate(start: DateTime, end: Option[DateTime]) extends JsonObject[EventDate] {
    def meta = EventDate
  }

  object EventDate extends JsonObjectMeta[EventDate]
}

, MongoDB, ... Rogue . Rogue :

  // Tell Lift about our DB
  val mongoAddr = MongoAddress(MongoHost("127.0.0.1", 27017), "scalaWebinar")

  MongoDB.defineDb(DefaultMongoIdentifier, mongoAddr)

  // Rogue gives us a saner approach, although still hobbled by some
  // of Lift-MongoDB-Record limits on embedded docs

  val q = MongoEvent where (_.eventType eqs EventType.Webinar)

  println("Rogue created a Query '%s'\n\n".format(q))

  for (x <- MongoEvent where (_.eventType eqs EventType.Webinar)) {
    println("Name: %s Presenter: %s\n".format(x.name, x.presenter))
  }

  // Rogue can also do sorting for you, which is useful

  println("\n\n\n")

  for (x <- MongoEvent where (_.eventType eqs EventType.Conference) 
                       orderAsc(_.language) andDesc(_.name)) { 
    println("Name: %s Language: %s\n".format(x.name, x.language))
  }
  val start = new DateTime(2011, 2, 1, 0, 0, 0, 0)
  val end = new DateTime(2011, 3, 1, 0, 0, 0, 0)

    /** The following would be nice but unfortunately, 
      doesn't work because of lift current embedded doc
      implementation
    */
  //val dateQ = MongoEvent where (_.date.start after start) 
                           //and (_.date.end before end)

, , Rogue Lift-Record , .

Casbah, DSL, Query MongoDB. , LOT , . ( ) Casbah Querying:

  // What about querying?  Lets find all the non-US events

  for (x <- mongo.find(MongoDBObject("location.country" -> 
                        MongoDBObject("$ne" -> "USA")))) println(x)

  /* There a problem here: We got back the Webinars too because 
     They don't have a country at all, so they aren't "USA"
    */
  println("\n\nTesting for existence of Location.Country:")

  for (x <- mongo.find(MongoDBObject("location.country" -> MongoDBObject(
                       "$ne" -> "USA",
                       "$exists" -> true 
                      )))) println(x)

  // This is getting a bit unwieldy.  Thankfully, Casbah offers a DSL
  val q = $or ("location.country" -> "USA", "location.country" -> "Japan")

  println("\n Created a DBObject: %s".format(q))

  println("\n Querying using DSL Object...")

  for (x <- mongo.find(q)) println(x)

  // It possible to construct more complex queries too.

  // Lets find everything in February

  println("\n February Events...")
  val start = new DateTime(2011, 2, 1, 0, 0, 0, 0)
  val end = new DateTime(2011, 3, 1, 0, 0, 0, 0)
  val dateQ = "date.start" $gte start $lt end 

  println("\n Date Query: %s".format(dateQ))

  for (x <- mongo.find(dateQ, MongoDBObject("name" -> true, "date" -> true))) println(x)

, , DSL MongoDB. , $type, :

"Casbah $type operator" should {
  "Accept raw Byte indicators (e.g. from org.bson.BSON)" in {
    // Don't need to test every value here since it just a byte
    val typeOper = "foo" $type org.bson.BSON.NUMBER_LONG
    typeOper must notBeNull
    typeOper.toString must notBeNull
    typeOper must haveSuperClass[DBObject]
    typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.NUMBER_LONG))
  }

  "Accept manifested Type arguments" in {
    "Doubles" in {
      val typeOper = "foo".$type[Double]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.NUMBER))
    }
    "Strings" in {
      val typeOper = "foo".$type[String]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.STRING))
    }
    "Object" in {
      "via BSONObject" in {
        val typeOper = "foo".$type[org.bson.BSONObject]
        typeOper must notBeNull
        typeOper.toString must notBeNull
        typeOper must haveSuperClass[DBObject]
        typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.OBJECT))
      }
      "via DBObject" in {
        val typeOper = "foo".$type[DBObject]
        typeOper must notBeNull
        typeOper.toString must notBeNull
        typeOper must haveSuperClass[DBObject]
        typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.OBJECT))
      }
    }
    "Array" in {
      "via BasicDBList" in {
        val typeOper = "foo".$type[BasicDBList]
        typeOper must notBeNull
        typeOper.toString must notBeNull
        typeOper must haveSuperClass[DBObject]
        typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.ARRAY))
      }
      "via BasicBSONList" in {
        val typeOper = "foo".$type[org.bson.types.BasicBSONList]
        typeOper must notBeNull
        typeOper.toString must notBeNull
        typeOper must haveSuperClass[DBObject]
        typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.ARRAY))
      }
    }
    "OID" in {
      val typeOper = "foo".$type[ObjectId]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.OID))
    }
    "Boolean" in {
      val typeOper = "foo".$type[Boolean]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.BOOLEAN))
    }
    "Date" in {
      "via JDKDate" in {
        val typeOper = "foo".$type[java.util.Date]
        typeOper must notBeNull
        typeOper.toString must notBeNull
        typeOper must haveSuperClass[DBObject]
        typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.DATE))
      }
      "via Joda DateTime" in {
        val typeOper = "foo".$type[org.joda.time.DateTime]
        typeOper must notBeNull
        typeOper.toString must notBeNull
        typeOper must haveSuperClass[DBObject]
        typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.DATE))
      }
    }
    "None (null)" in {
      // For some reason you can't use NONE 
      val typeOper = "foo".$type[Option[Nothing]]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.NULL))
    }
    "Regex" in {
      "Scala Regex" in {
        val typeOper = "foo".$type[scala.util.matching.Regex]
        typeOper must notBeNull
        typeOper.toString must notBeNull
        typeOper must haveSuperClass[DBObject]
        typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.REGEX))
      }
    }
    "Symbol" in {
      val typeOper = "foo".$type[Symbol]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.SYMBOL))
    }
    "Number (integer)" in {
      val typeOper = "foo".$type[Int]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.NUMBER_INT))
    }
    "Number (Long)" in {
      val typeOper = "foo".$type[Long]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.NUMBER_LONG))
    }
    "Timestamp" in {
      val typeOper = "foo".$type[java.sql.Timestamp]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.TIMESTAMP))
    }
    "Binary" in {
      val typeOper = "foo".$type[Array[Byte]]
      typeOper must notBeNull
      typeOper.toString must notBeNull
      typeOper must haveSuperClass[DBObject]
      typeOper must beEqualTo(nonDSL("foo", "$type", org.bson.BSON.BINARY))
    }

  }

(. casbah-query, , "casbah" ). Casbah DSL; , Specs . , Casbah , MongoDB.

, $. $set, $rename .. . Bareword.

- , , $type. . .

, , , , . Casbah DSL, MongoDB (, Casbah getAs[T] DBObject DBObject , ); , DSL , -, , . Casbah Query DSL "" ... ** MONGODB * , MongoDB, DSL. , , Rogue .

, Rogue Record, .

, , " " , .

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