Merge pull request #31 from AugustNagro/nullable-uuid

support optional uuid columns

README.md

@@ -590,6 +590,21 @@ case class Address(
 ) derives DbCodec
 ```
 
+#### UUID DbCodec doesn't work for my database
+
+Some databases directly support the UUID type; these include Postgres, Clickhouse, and H2. When using the built-in `DbCodec[UUID]`, defined in `DbCodec.scala`, serialization and deserialization of `java.util.UUID` will work as expected.
+
+Other databases like MySql, Oracle, and Sqlite, however, do not natively support UUID columns. Users have to choose an alternate datatype to store the UUID: most commonly `varchar(36)` or `binary(16)`. The JDBC drivers for these databases do not support direct serialization and deserialization of `java.util.UUID`, therefore the default `DbCodec[UUID]` will not be sufficient. Instead, import the appropriate codec from `com.augustnagro.magnum.UUIDCodec`. For example,
+
+```scala
+import com.augustnagro.magnum.*
+import com.augustnagro.magnum.UUIDCodec.VarCharUUIDCodec
+import java.util.UUID
+
+@Table(MySqlDbType)
+case class Person(@Id id: Long, name: String, tracking_id: Option[UUID]) derives DbCodec
+```
+
 ## Todo
 * JSON / XML support
 * Support MSSql

magnum/src/main/scala/com/augustnagro/magnum/DbCodec.scala

@@ -291,7 +291,7 @@ object DbCodec:
 
   given UUIDCodec: DbCodec[UUID] with
     def queryRepr: String = "?"
-    val cols: IArray[Int] = IArray(Types.JAVA_OBJECT)
+    val cols: IArray[Int] = IArray(Types.OTHER)
     def readSingle(rs: ResultSet, pos: Int): UUID =
       rs.getObject(pos, classOf[UUID])
     def writeSingle(entity: UUID, ps: PreparedStatement, pos: Int): Unit =

magnum/src/main/scala/com/augustnagro/magnum/UUIDCodec.scala

@@ -0,0 +1,15 @@
+package com.augustnagro.magnum
+
+import java.sql.{PreparedStatement, ResultSet, Types}
+import java.util.UUID
+
+object UUIDCodec:
+  given VarCharUUIDCodec: DbCodec[UUID] with
+    def queryRepr: String = "?"
+    val cols: IArray[Int] = IArray(Types.VARCHAR)
+    def readSingle(rs: ResultSet, pos: Int): UUID =
+      rs.getString(pos) match
+        case null    => null
+        case uuidStr => UUID.fromString(uuidStr)
+    def writeSingle(entity: UUID, ps: PreparedStatement, pos: Int): Unit =
+      ps.setString(pos, entity.toString)

magnum/src/test/resources/clickhouse-person.sql

@@ -5,7 +5,8 @@ create table person (
     first_name Nullable(String),
     last_name String not null,
     is_admin Bool not null,
-    created DateTime not null default now()
+    created DateTime not null default now(),
+    social_id Nullable(UUID)
 )
 engine = MergeTree()
 order by created;
@@ -16,54 +17,62 @@ insert into person values
     'George',
     'Washington',
     true,
-    toDateTime('2023-03-05 02:26:00')
+    toDateTime('2023-03-05 02:26:00'),
+    toUUID('d06443a6-3efb-46c4-a66a-a80a8a9a5388')
 ),
 (
     toUUID('12970806-606d-42ff-bb9c-3187bbd360dd'),
     'Alexander',
     'Hamilton',
     true,
-    toDateTime('2023-03-05 02:27:00')
+    toDateTime('2023-03-05 02:27:00'),
+    toUUID('529b6c6d-7228-4da5-81d7-13b706f78ddb')
 ),
 (
     toUUID('834a2bd2-6842-424f-97e0-fe5ed02c3653'),
     'John',
     'Adams',
     true,
-    toDateTime('2023-03-05 02:28:00')
+    toDateTime('2023-03-05 02:28:00'),
+    null
 ),
 (
     toUUID('60492bb2-fe02-4d02-9c6d-ae03fa6f2243'),
     'Benjamin',
     'Franklin',
     true,
-    toDateTime('2023-03-05 02:29:00')
+    toDateTime('2023-03-05 02:29:00'),
+    null
 ),
 (
     toUUID('2244eef4-b581-4305-824f-efe8f70e6bb7'),
     'John',
     'Jay',
     true,
-    toDateTime('2023-03-05 02:30:00')
+    toDateTime('2023-03-05 02:30:00'),
+    null
 ),
 (
     toUUID('fb3c479a-0521-4f06-b6ad-218db867518c'),
     'Thomas',
     'Jefferson',
     true,
-    toDateTime('2023-03-05 02:31:00')
+    toDateTime('2023-03-05 02:31:00'),
+    null
 ),
 (
     toUUID('8fefe1d8-20eb-44a0-84da-d328334e1e11'),
     'James',
     'Madison',
     true,
-    toDateTime('2023-03-05 02:32:00')
+    toDateTime('2023-03-05 02:32:00'),
+    null
 ),
 (
     toUUID('8a2d842a-0d03-463c-8c34-43b38120f9e4'),
     null,
     'Nagro',
     false,
-    toDateTime('2023-03-05 02:33:00')
+    toDateTime('2023-03-05 02:33:00'),
+    null
 );

magnum/src/test/resources/h2-person.sql

@@ -5,15 +5,16 @@ create table person (
     first_name varchar(50),
     last_name varchar(50) not null,
     is_admin boolean not null,
-    created timestamp default current_timestamp
+    created timestamp default current_timestamp,
+    social_id UUID
 );
 
-insert into person (first_name, last_name, is_admin, created) values
-('George', 'Washington', true, now()),
-('Alexander', 'Hamilton', true, now()),
-('John', 'Adams', true, now()),
-('Benjamin', 'Franklin', true, now()),
-('John', 'Jay', true, now()),
-('Thomas', 'Jefferson', true, now()),
-('James', 'Madison', true, now()),
-(null, 'Nagro', false, now());
+insert into person (first_name, last_name, is_admin, created, social_id) values
+('George', 'Washington', true, now(), 'd06443a6-3efb-46c4-a66a-a80a8a9a5388'),
+('Alexander', 'Hamilton', true, now(), '529b6c6d-7228-4da5-81d7-13b706f78ddb'),
+('John', 'Adams', true, now(), null),
+('Benjamin', 'Franklin', true, now(), null),
+('John', 'Jay', true, now(), null),
+('Thomas', 'Jefferson', true, now(), null),
+('James', 'Madison', true, now(), null),
+(null, 'Nagro', false, now(), null);

magnum/src/test/resources/mysql-person.sql

@@ -5,15 +5,16 @@ create table person (
     first_name varchar(50),
     last_name varchar(50) not null,
     is_admin boolean not null,
-    created timestamp default current_timestamp
+    created timestamp default current_timestamp,
+    social_id varchar(36)
 );
 
-insert into person (first_name, last_name, is_admin, created) values
-('George', 'Washington', true, now()),
-('Alexander', 'Hamilton', true, now()),
-('John', 'Adams', true, now()),
-('Benjamin', 'Franklin', true, now()),
-('John', 'Jay', true, now()),
-('Thomas', 'Jefferson', true, now()),
-('James', 'Madison', true, now()),
-(null, 'Nagro', false, now());
+insert into person (first_name, last_name, is_admin, created, social_id) values
+('George', 'Washington', true, now(), 'd06443a6-3efb-46c4-a66a-a80a8a9a5388'),
+('Alexander', 'Hamilton', true, now(), '529b6c6d-7228-4da5-81d7-13b706f78ddb'),
+('John', 'Adams', true, now(), null),
+('Benjamin', 'Franklin', true, now(), null),
+('John', 'Jay', true, now(), null),
+('Thomas', 'Jefferson', true, now(), null),
+('James', 'Madison', true, now(), null),
+(null, 'Nagro', false, now(), null);

magnum/src/test/resources/pg-person.sql

@@ -5,15 +5,16 @@ create table person (
     first_name varchar(50),
     last_name varchar(50) not null,
     is_admin boolean not null,
-    created timestamptz not null default now()
+    created timestamptz not null default now(),
+    social_id UUID
 );
 
-insert into person (first_name, last_name, is_admin, created) values
-('George', 'Washington', true, now()),
-('Alexander', 'Hamilton', true, now()),
-('John', 'Adams', true, now()),
-('Benjamin', 'Franklin', true, now()),
-('John', 'Jay', true, now()),
-('Thomas', 'Jefferson', true, now()),
-('James', 'Madison', true, now()),
-(null, 'Nagro', false, timestamp '1997-08-12');
+insert into person (first_name, last_name, is_admin, created, social_id) values
+('George', 'Washington', true, now(), 'd06443a6-3efb-46c4-a66a-a80a8a9a5388'),
+('Alexander', 'Hamilton', true, now(), '529b6c6d-7228-4da5-81d7-13b706f78ddb'),
+('John', 'Adams', true, now(), null),
+('Benjamin', 'Franklin', true, now(), null),
+('John', 'Jay', true, now(), null),
+('Thomas', 'Jefferson', true, now(), null),
+('James', 'Madison', true, now(), null),
+(null, 'Nagro', false, timestamp '1997-08-12', null);

magnum/src/test/scala/ClickHouseTests.scala

@@ -163,7 +163,8 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
       firstName: Option[String],
       lastName: String,
       isAdmin: Boolean,
-      created: OffsetDateTime
+      created: OffsetDateTime,
+      socialId: Option[UUID]
   ) derives DbCodec
 
   val personRepo = Repo[Person, Person, UUID]
@@ -201,7 +202,8 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
           firstName = Some("John"),
           lastName = "Smith",
           isAdmin = false,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = Some(UUID.randomUUID())
         )
       )
       personRepo.insert(
@@ -210,7 +212,8 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
           firstName = None,
           lastName = "Prince",
           isAdmin = true,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = None
         )
       )
       assertEquals(personRepo.count, 10L)
@@ -225,14 +228,16 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
             firstName = Some("John"),
             lastName = "Smith",
             isAdmin = false,
-            created = OffsetDateTime.now
+            created = OffsetDateTime.now,
+            socialId = Some(UUID.randomUUID())
           ),
           Person(
             id = UUID.randomUUID,
             firstName = None,
             lastName = "Prince",
             isAdmin = true,
-            created = OffsetDateTime.now
+            created = OffsetDateTime.now,
+            socialId = None
           )
         )
       )
@@ -247,7 +252,8 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
           firstName = Some("John"),
           lastName = "Smith",
           isAdmin = false,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = Some(UUID.randomUUID())
         )
       )
       assertEquals(personRepo.count, 9L)
@@ -261,14 +267,16 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
           firstName = Some("John"),
           lastName = "Smith",
           isAdmin = false,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = Some(UUID.randomUUID())
         ),
         Person(
           id = UUID.randomUUID,
           firstName = None,
           lastName = "Prince",
           isAdmin = true,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = None
         )
       )
       val people = personRepo.insertAllReturning(ps)
@@ -283,7 +291,8 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
           firstName = None,
           lastName = null,
           isAdmin = false,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = None
         )
         personRepo.insert(invalidP)
 
@@ -310,14 +319,16 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
           firstName = Some("John"),
           lastName = "Smith",
           isAdmin = false,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = Some(UUID.randomUUID())
         ),
         Person(
           id = UUID.randomUUID,
           firstName = None,
           lastName = "Prince",
           isAdmin = true,
-          created = OffsetDateTime.now
+          created = OffsetDateTime.now,
+          socialId = None
         )
       )
       personRepo.insertAll(newPeople)
@@ -347,13 +358,14 @@ class ClickHouseTests extends FunSuite, TestContainersFixtures:
         firstName = Some("John"),
         lastName = "Smith",
         isAdmin = false,
-        created = OffsetDateTime.now
+        created = OffsetDateTime.now,
+        socialId = Some(UUID.randomUUID())
       )
       val update =
         sql"insert into $person ${person.insertColumns} values ($p)".update
       assertNoDiff(
         update.frag.sqlString,
-        "insert into person (id, first_name, last_name, is_admin, created) values (?, ?, ?, ?, ?)"
+        "insert into person (id, first_name, last_name, is_admin, created, social_id) values (?, ?, ?, ?, ?, ?)"
       )
       val rowsInserted = update.run()
       assertEquals(rowsInserted, 1)