Typed Parquet Annotations (#604)

* Collecting parquet annotations and storing them in the map

Implemented SchemaUtil deepCopy with parquet annotations enrichment

Fix errors

Added more tests

Improve error message (#611)

Make implicit field from EnumType low priority (#613)

Fix build

* Improve parquet annotation support

* dded more checks into AvroSchemaComparer

* address review comments

* address review comments 2

* Addressed PR comments

Co-authored-by: Michel Davit <[email protected]>

avro/src/main/scala/magnolify/avro/AvroType.scala

@@ -32,10 +32,6 @@ import scala.reflect.ClassTag
 import scala.jdk.CollectionConverters._
 import scala.collection.compat._
 
-class doc(doc: String) extends StaticAnnotation with Serializable {
-  override def toString: String = doc
-}
-
 sealed trait AvroType[T] extends Converter[T, GenericRecord, GenericRecord] {
   val schema: Schema
   def apply(r: GenericRecord): T = from(r)

avro/src/main/scala/magnolify/avro/package.scala

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2022 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package magnolify
+
+package object avro {
+  type doc = shared.doc
+}

build.sbt

@@ -189,6 +189,12 @@ val commonSettings = Seq(
       name = "Shameera Rathnayaka Yodage",
       email = "[email protected]",
       url = url("https://twitter.com/syodage")
+    ),
+    Developer(
+      id = "shnapz",
+      name = "Andrew Kabas",
+      email = "[email protected]",
+      url = url("https://github.com/shnapz")
     )
   )
 )

docs/parquet.md

@@ -48,3 +48,14 @@ implicit val pfDecimalBinary = ParquetField.decimalBinary(20, 0)
 Among the date/time types, `DATE` maps to `java.time.LocalDate`. The other types, `TIME` and `TIMESTAMP`, map to `OffsetTime`/`LocalTime` and `Instant`/`LocalDateTime` with `isAdjustedToUTC` set to `true`/`false`. They can be in nano, micro, or milliseconds precision with `import magnolify.parquet.logical.{nanos,micros,millis}._`.
 
 Note that Parquet's official Avro support maps `REPEATED` fields to an `array` field inside a nested group. Use `import magnolify.parquet.ParquetArray.AvroCompat._` to ensure compatibility with Avro.
+
+The top level class and all fields (including nested class fields) can be annotated with `@doc` annotation. Note that nested classes annotations are ignored.
+
+```scala
+@doc("This is ignored")
+case class NestedClass(@doc("nested field annotation") i: Int)
+
+@doc("Top level annotation")
+case class TopLevelType(@doc("field annotation") pd: NestedClass, @doc("field annotation 2") i: 
+Integers)
+```