I am learning ReactiveMongo. In my application, I want to retrieve data from MongoDB and fill it in an HTML form.
Earlier my problem was that code wasn't compiling. I fixed it but now I am getting None.get instead of value from database.
The data I have in MongoDB will map to following case class
case class User2(
name:String,
email:String,
age:Int,
gender:Boolean
)
Following is the reader required by Reactive Mongo.
Question1 - I am getting None.get instead of value from MongoDB
object User2{
implicit object UserReader extends BSONDocumentReader[User2] {
def read(doc: BSONDocument): User2= {
val name = doc.getAs[String]("name").get
val email = doc.getAs[String]("email").get
val age = doc.getAs[Int]("age").get
val gender = doc.getAs[Boolean]("gender").get
User2(name, email, age, gender)
}
}
}
Following is my controller code. Ignore the unnecessary imports
package controllers
import anorm.{NotAssigned, Pk}
import play.api.data.Form
import play.api.data.Form._
import play.api.data.Forms
import play.api.mvc.Controller
import play.api.mvc._
import play.api.data.Forms._
import play.api.data.validation.Constraints._
import play.api.db.DB
import models._
import scala.concurrent._
import ExecutionContext.Implicits.global
import scala.util.Try
import reactivemongo.api.MongoDriver
import reactivemongo.bson._
import reactivemongo.api.MongoConnection
import reactivemongo.api.collections.default.BSONCollection
object Application_Test extends Controller {
val user2Form: Form[User2] = Form(
mapping(
"name" -> nonEmptyText,
"email" -> email,
"age" -> number,
"gender" -> boolean
)(User2.apply)(User2.unapply)
)
def index = Action {
Async {
val driver = new MongoDriver()
val connection = driver.connection(List("localhost"))
val db = connection.db("website-users")
val collection = db.collection[BSONCollection]("user-table")
val query = BSONDocument("name" -> "Manu")
val result = collection.find(query).cursor[User2].collect[List]()
/*
result.map { user =>
//following code doesn't compile. I think result is List[models.User2]. I tried using user and user(0) but none of them compile
Ok(views.html.HTMLTest(user2Form.fill(user)))
}
*/
// this version of code compiles
result.map { user => user match {
case List() => Ok(views.html.HTMLTest(user2Form.fill(User2("a","a@a.com",1,true))))
case h::v => Ok (views.html.HTMLTest (user2Form.fill (h) ) )
}
}
}
}
}
Following is the HTML
Question2 - is @form("name").value the correct way to extract a value from a Form?
@(form:Form[User2])
<!DOCTYPE html>
<html lang="en" xmlns:font-variant="http://www.w3.org/1999/xhtml">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-COMPATIBLE" content="IE=edge">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>HTML Test</title>
<link rel="stylesheet" type="text/css" href="@routes.Assets.at("stylesheets/bootstrap.min.css")">
<!--link rel="stylesheet" href="stylesheets/bootstrap-theme.min.css"-->
<style type="text/css">
html, body{height:100%; margin:0;padding:0}
.center-form {
width:100%;
margin:auto;
position:relative;
top:50%;
transform: translateY(-50%)
}
</style>
</head>
<body>
<div class="container center-form" >
<!-- for medium and large screens,
First row of Bootstrap grid contains logo. Total 3 columns (12/4). Logo in middle column-->
<div class="row" >
<!--empty column-->
<div class="col-md-4 col-lg-4" ></div>
<!--logo column-->
<div class="col-md-4 col-lg-4" >
<div>
<img src="@routes.Assets.at("images/Logo303x64.png")" alt="SalesWorkspace Logo" height="64" width="303">
</div>
</div>
<!--empty column-->
<div class="col-md-4 col-lg-4"></div>
</div>
<!-- for medium and large screens,
Second row of Bootstrap grid contains the form for username and password. Total 3 columns (12/4). -->
<div class="row" >
<!--empty column-->
<div class="col-md-4 col-lg-4"></div>
<!--form-->
<div class="col-md-4 col-lg-4">
<form>
<div class="form-group">
<label for="first-name">First Name</label>
<input type="text" class="form-control" id="first-name" value="@form("name").value" required>
</div>
<div class="form-group">
<label for="last-name">Last Name</label>
<input type="text" class="form-control" id="last-name" value="@form("name").value" required>
</div>
<div class="form-group">
<label for="email">Email</label>
<input type="email" class="form-control" id="email" value="@form("email").value" required>
</div>
<div class="form-group">
<label for="password">Password</label>
<input type="password" class="form-control" id="password" required>
</div>
<div class="form-group">
<label for="confirm-password">Password</label>
<input type="password" class="form-control" id="confirm-password" required>
</div>
<button type="submit" class="btn btn-primary">Login</button>
</form>
</div>
<!--empty column-->
<div class="col-md-4 col-lg-4"></div>
</div>
</div>
<!--script src="@routes.Assets.at("javascripts/jquery-1.9.0.min")"></script-->
<!--script src="@routes.Assets.at("javascripts/bootstrap.min.js")"></script-->
</body>
</html>
As indicated in the API documentation, BSONDocument.getAs[T] returns an Option[T] and so could be used for optional document field.
Apply .get on such Option is clearly a code smell.
If you want to get a field which is assumed to be required, you'd better use .getAsTry which would give details in case of error (more helpful than NoSuchElementException from None.get).
def read(doc: BSONDocument): User2= (for {
name <- doc.getAsTry[String]("name")
email <- doc.getAsTry[String]("email")
age <- doc.getAsTry[Int]("age")
gender <- doc.getAsTry[Boolean]("gender")
} yield User2(name, email, age, gender)).get