I have an article collection where fields "title" and "publication" has a unique combined key constraint.
When calling insertOrUpdateArticle(a: Article) it will first try to insert it, in case it hits the constraint, it should update the article - if needed.
However, I'm stuck before that. Current error is:
Error:(88, 57) type mismatch;
found : scala.concurrent.Future[scala.concurrent.Future[Boolean]]
required: Boolean
col_article.find(selector).one[Article].map {
Source:
def insertOrUpdateArticle(a: Article): Future[Boolean] = {
// try insert article
col_article.insert[Article](a).map {
// article inserted
lastError => {
println("Article added.")
true
}
}.recover {
case lastError: LastError =>
// check if article existed
lastError.code.get match {
case 11000 => {
// article existed (duplicate key error)
// load old article
val selector = BSONDocument(
"title" -> BSONString(a.title),
"publication" -> BSONString(a.publication)
)
col_article.find(selector).one[Article].map {
case Some(old_a: Article) => {
// TODO: compare a with old_a
// TODO: if a differs from old_a, update
Future(true)
}
case None => {
// something went wrong
Future(false)
}
}
}
case _ => {
println("DB.insertOrUpdateArticle() unexpected error code when inserting: " + lastError.code.get)
false
}
}
case ex =>
println("DB.insertOrUpdateArticle() unexpected exception when inserting: " + ex)
false
}
}
I'm unsure what to do here. The code should return Future(true) if the article was saved or updated, false otherwise. There's something with reactivemongo and/or scala futures I'm missing out here.
Using recoverWith to create new Future is the solution, modified code:
def insertOrUpdateArticleOld(a: Article): Future[Boolean] = {
// try insert article
col_article.insert[Article](a).map {
// article inserted
lastError => {
println("Article added.")
true
}
}.recoverWith {
case lastError: LastError =>
// check if article existed
lastError.code.get match {
case 11000 => {
// article existed (duplicate key error)
// load old article
val selector = BSONDocument(
"title" -> BSONString(a.title),
"publication" -> BSONString(a.publication)
)
col_article.find(selector).one[Article].flatMap {
case Some(old_a: Article) => {
// TODO: compare a with old_a
// TODO: if a differs from old_a, update
Future(true)
}
case None => {
// something went wrong
Future(false)
}
}
}
case _ => {
println("DB.insertOrUpdateArticle() unexpected error code when inserting: " + lastError.code.get)
Future(false)
}
}
case ex =>
println("DB.insertOrUpdateArticle() unexpected exception when inserting: " + ex)
Future(false)
}
}