Refactor database API to use for-comprehensions.

src/main/scala/gay/creatures/unit_ca5/db/modules/uac/UACAPI.scala

@@ -35,113 +35,75 @@ class UACAPI(
 	
 	def setup: DBIO[Unit] =
 		DBIO.seq(
-			(queries.UACBase.schema ++ queries.tokenScopeBase.schema).createIfNotExists
+			(
+				queries.UACBase.schema 
+				++ queries.tokenScopeBase.schema
+			).createIfNotExists
 		)
 
-	def create(cred: UserAuthenticationCredential)(implicit ec: ExecutionContext): DBIO[Option[Int]] = 
-		queries.UACBase.returning(queries.UACBase.map(_.id)).+=(
-			queries.schema.RawUAC(
-				0,
-				cred.userId,
-				cred.accessToken,
-				cred.refreshToken,
-				cred.expires
-			)
-		).flatMap(uacId =>
-			queries.tokenScopeBase.++=(
+	/**
+	  * Construct a query to add a new UserAuthenticationCredential to the
+	  * database.
+	  *
+	  * @param cred Credential to insert.
+	  * @return A query object. Pass it to `exec.execute()` to run it.
+	  */
+	def create(
+		cred: UserAuthenticationCredential
+	)(
+		implicit ec: ExecutionContext
+	): DBIO[Option[Int]] = 
+		for 
+			// Insert base UAC
+			base <- queries.UACBase.returning(queries.UACBase.map(_.id)) +=
+				queries.schema.RawUAC(
+					0, 
+					cred.userId, 
+					cred.accessToken, 
+					cred.refreshToken, 
+					cred.expires
+				)
+
+			// Insert scopes for UAC
+			scopes <- queries.tokenScopeBase ++=
 				cred.scopes.map(scope =>
 					queries.schema.UACTokenScope(
-						uacId,
+						base,
 						scope.uid
 					)
 				)
-			)
-		)
+		yield scopes
 
-	def retrieve(user: TwitchUID)(implicit ec: ExecutionContext): DBIO[UserAuthenticationCredential] =
-		// Construct query for base UAC data
-		queries.UACBase.filter(
-			_.userId === user
-		).take(1)
-		.result.headOption // Take only the first UAC that matches (there should never be more than one)
-		.flatMap(res => // With the result of that query:
-			res match
-				case None => slick.dbio.FailureAction(NotFoundException()) // Don't attempt to retrieve scopes if there's no matching UAC
+	def retrieve(
+		user: TwitchUID
+	)(
+		implicit ec: ExecutionContext
+	): DBIO[UserAuthenticationCredential] =
+		for
+			// Query the base UAC
+			uac <- queries.UACBase.filter(
+				_.userId === user
+			).take(1).result.headOption
+
+			// Query the scopes (if the base UAC returns)
+			scopes <- uac match
+				case None => slick.dbio.FailureAction(NotFoundException())
 				case Some(uac) =>
-					// Construct a query to retrieve relevant scopes
-					queries.tokenScopeBase.filter( scope =>
+					queries.tokenScopeBase.filter(scope =>
 						scope.tokenId === uac.id
-					).result.map(res =>
-						val convertedScopes = res.map(scope => 
-							// Convert UIDs to TokenScope enums
-							TokenScope.fromUid(scope.scopeId)
-						).filter(mappedScope =>
-							// Filter any UIDs that didn't match TokenScopes.
-							mappedScope match
-								case None => false
-								case _    => true
-						).map(convertedScope =>
-							// Strip the Options.
-							convertedScope.get
-						)
+					).result
 
-						UserAuthenticationCredential(
-							uac.userId,
-							uac.accessToken,
-							uac.refreshToken,
-							uac.expires,
-							convertedScopes.toList
-						)
-					)
+		yield UserAuthenticationCredential(
+			uac.get.userId,
+			uac.get.accessToken,
+			uac.get.refreshToken,
+			uac.get.expires,
+			// n.b. - `flatten` removes scope IDs that don't map properly.
+			scopes.map(scope =>
+				TokenScope.fromUid(scope.scopeId)
+			).flatten.toList 
 		)
 
-		// val action = database.run(query).flatMap( res =>
-		//     res match
-		//         case None => Future{None}
-		//         case Some(uac) =>
-		//             // Construct query for 
-		//             val scopesQuery = queries.tokenScopeBase.filter( scope =>
-		//                 scope.tokenId === uac.id
-		//             ).result.map(res =>
-		//                 res.map(scope => 
-		//                     // Convert UIDs to TokenScope enums
-		//                     TokenScope.fromUid(scope.scopeId)
-		//                 ).filter(mappedScope =>
-		//                     // Filter any UIDs that didn't match TokenScopes.
-		//                     mappedScope match
-		//                         case None => false
-		//                         case _    => true
-		//                 ).map(convertedScope =>
-		//                     // Strip the Options.
-		//                     convertedScope.get
-		//                 )
-		//             )
-
-		//             database.run(scopesQuery).map(res =>
-		//                 UserAuthenticationCredential(
-		//                     uac.userId,
-		//                     uac.accessToken,
-		//                     uac.refreshToken,
-		//                     uac.expires,
-		//                     res.toList
-		//                 )
-		//             )
-		// )
-		
-		// .map((res) =>
-		//     val queryResult: Option[queries.schema.RawUAC] = 
-		//         if res.length > 0 then Some(res[0]) else None
-
-		//     if queryResult == None then
-		//         throw Exception
-
-		//     val scopesQuery = queries.tokenScopeBase.filter(
-		//         _.tokenId === queryResult.accessToken
-		//     ).take(1).result
-		// )
-
-		// action
-
 	def delete(user: TwitchUID): Future[Unit] = ???