feat!: Schema-based serialization

Sources/Smithy/Document/Implementations/BigDecimalDocument.swift

@@ -35,8 +35,8 @@ public struct BigDecimalDocument: SmithyDocument {
         return int
     }
 
-    public func asLong() throws -> Int64 {
-        guard let long = Int64(exactly: value) else {
+    public func asLong() throws -> Int {
+        guard let long = Int(exactly: value) else {
             throw DocumentError.numberOverflow("BigDecimal \(value) overflows long")
         }
         return long

Sources/Smithy/Document/ShapeType.swift

@@ -8,6 +8,14 @@
 /// Reproduces the cases in Smithy `ShapeType`.
 /// https://github.com/smithy-lang/smithy/blob/main/smithy-model/src/main/java/software/amazon/smithy/model/shapes/ShapeType.java
 public enum ShapeType {
+
+    public enum Category {
+        case simple
+        case aggregate
+        case service
+        case member
+    }
+
     case blob
     case boolean
     case string
@@ -32,4 +40,18 @@ public enum ShapeType {
     case service
     case resource
     case operation
+
+    public var category: Category {
+        switch self {
+        case .blob, .boolean, .string, .timestamp, .byte, .short, .integer, .long,
+             .float, .document, .double, .bigDecimal, .bigInteger, .enum, .intEnum:
+            return .simple
+        case .list, .set, .map, .structure, .union:
+            return .aggregate
+        case .service, .resource, .operation:
+            return .service
+        case .member:
+            return .member
+        }
+    }
 }

Sources/SmithyJSON/Reader/Reader+ShapeDeserializer.swift

@@ -0,0 +1,259 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import struct Foundation.Data
+import struct Foundation.Date
+import struct Foundation.TimeInterval
+import struct Smithy.Document
+import protocol Smithy.SmithyDocument
+import enum SmithyReadWrite.ReaderError
+@_spi(SmithyReadWrite) import protocol SmithyReadWrite.ShapeDeserializer
+@_spi(SmithyReadWrite) import protocol SmithyReadWrite.SchemaProtocol
+@_spi(SmithyReadWrite) import struct SmithyReadWrite.Schema
+@_spi(SmithyTimestamps) import enum SmithyTimestamps.TimestampFormat
+
+@_spi(SmithyReadWrite)
+extension Reader: SmithyReadWrite.ShapeDeserializer {
+
+    public func readStructure<Target>(schema: SmithyReadWrite.Schema<Target>) throws -> Target? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        let structureSchema = resolvedTargetSchema(schema: schema)
+        guard let factory = structureSchema.factory else {
+            throw ReaderError.invalidSchema("Missing factory for structure or union: \(structureSchema.id)")
+        }
+        guard resolvedReader.hasContent, resolvedReader.jsonNode == .object else {
+            return resolvedDefault(schema: schema) != nil ? factory() : nil
+        }
+        var value = factory()
+        try structureSchema.members.forEach { memberContainer in
+            try memberContainer.performRead(base: &value, key: "", reader: resolvedReader)
+        }
+        return value
+    }
+
+    public func readList<T>(schema: Schema<[T]>) throws -> [T]? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, resolvedReader.jsonNode == .array else {
+            return resolvedDefault(schema: schema) != nil ? [] : nil
+        }
+        let listSchema = resolvedTargetSchema(schema: schema)
+        guard let memberContainer = listSchema.members.first(
+            where: { $0.member.memberSchema().memberName == "member" }
+        ) else {
+            throw ReaderError.requiredValueNotPresent
+        }
+        var value = [T]()
+        for child in resolvedReader.children {
+            try memberContainer.performRead(base: &value, key: "", reader: child)
+        }
+        return value
+    }
+
+    public func readMap<T>(schema: Schema<[String: T]>) throws -> [String: T]? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, resolvedReader.jsonNode == .object else {
+            return resolvedDefault(schema: schema) != nil ? [:] : nil
+        }
+        let mapSchema = resolvedTargetSchema(schema: schema)
+        guard let valueContainer = mapSchema.members.first(
+            where: { $0.member.memberSchema().memberName == "value" }
+        ) else {
+            throw ReaderError.requiredValueNotPresent
+        }
+        var value = [String: T]()
+        for child in resolvedReader.children {
+            if !mapSchema.isSparse && child.jsonNode == .null { continue }
+            try valueContainer.performRead(base: &value, key: child.nodeInfo.name, reader: child)
+        }
+        return value
+    }
+
+    public func readEnum<T: RawRepresentable>(schema: Schema<T>) throws -> T? where T.RawValue == String {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .string = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema).map { T(rawValue: try $0.asString())! }
+        }
+        guard let rawValue: String = try resolvedReader.readIfPresent() else { return nil }
+        return T(rawValue: rawValue)
+    }
+
+    public func readIntEnum<T: RawRepresentable>(schema: Schema<T>) throws -> T? where T.RawValue == Int {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .number = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema).map { T(rawValue: try $0.asInteger())! }
+        }
+        guard let rawValue: Int = try resolvedReader.readIfPresent() else { return nil }
+        return T(rawValue: rawValue)
+    }
+
+    public func readString(schema: Schema<String>) throws -> String? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .string = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema)?.asString()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readBoolean(schema: SmithyReadWrite.Schema<Bool>) throws -> Bool? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .bool = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema)?.asBoolean()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readByte(schema: SmithyReadWrite.Schema<Int8>) throws -> Int8? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .number = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema)?.asByte()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readShort(schema: SmithyReadWrite.Schema<Int16>) throws -> Int16? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .number = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema)?.asShort()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readInteger(schema: SmithyReadWrite.Schema<Int>) throws -> Int? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .number = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema)?.asInteger()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readLong(schema: SmithyReadWrite.Schema<Int>) throws -> Int? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .number = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema)?.asInteger()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readFloat(schema: SmithyReadWrite.Schema<Float>) throws -> Float? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent else {
+            return try resolvedDefault(schema: schema)?.asFloat()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readDouble(schema: SmithyReadWrite.Schema<Double>) throws -> Double? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent else {
+            return try resolvedDefault(schema: schema)?.asDouble()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readBigInteger(schema: SmithyReadWrite.Schema<Int64>) throws -> Int64? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .number = resolvedReader.jsonNode else {
+            return try resolvedDefault(schema: schema)?.asBigInteger()
+        }
+        let int: Int? = try resolvedReader.readIfPresent()
+        return int.map { Int64($0) }
+    }
+
+    public func readBigDecimal(schema: SmithyReadWrite.Schema<Double>) throws -> Double? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent else {
+            return try resolvedDefault(schema: schema)?.asDouble()
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readBlob(schema: SmithyReadWrite.Schema<Data>) throws -> Data? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .string = resolvedReader.jsonNode else {
+            guard let base64String = try resolvedDefault(schema: schema)?.asString() else { return nil }
+            return Data(base64Encoded: base64String)
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readTimestamp(schema: SmithyReadWrite.Schema<Date>) throws -> Date? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent else {
+            guard let defaultValue = resolvedDefault(schema: schema) else { return nil }
+            switch defaultValue.type {
+            case .float:
+                let interval = try TimeInterval(defaultValue.asFloat())
+                return Date(timeIntervalSince1970: interval)
+            case .double:
+                return try Date(timeIntervalSince1970: defaultValue.asDouble())
+            case .timestamp:
+                return try defaultValue.asTimestamp()
+            default:
+                throw ReaderError.invalidSchema("Unsupported timestamp default type: \(defaultValue.type)")
+            }
+        }
+        let memberSchema = schema.type == .member ? schema : nil
+        let timestampSchema = schema.targetSchema() ?? schema
+        let resolvedTimestampFormat = memberSchema?.timestampFormat ?? timestampSchema.timestampFormat
+        return try resolvedReader.readTimestampIfPresent(format: resolvedTimestampFormat ?? .epochSeconds)
+    }
+
+    public func readDocument(schema: SmithyReadWrite.Schema<Document>) throws -> Document? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent else {
+            return resolvedDefault(schema: schema).map { Document($0) }
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    public func readNull(schema: any SmithyReadWrite.SchemaProtocol) throws -> Bool? {
+        let resolvedReader = try resolvedReader(schema: schema)
+        guard resolvedReader.hasContent, case .null = resolvedReader.jsonNode else {
+            return false
+        }
+        return try resolvedReader.readIfPresent()
+    }
+
+    private func resolvedReader(schema: any SchemaProtocol) throws -> Reader {
+        if schema.httpPayload {
+            return self
+        } else if schema.containerType == .map || schema.containerType == .list || schema.containerType == .set {
+            return self
+        } else if schema.type == .member {
+            let resolvedName = try resolvedName(memberSchema: schema)
+            return self[NodeInfo(resolvedName)]
+        } else {
+            return self
+        }
+    }
+
+    private func resolvedDefault<Target>(schema: Schema<Target>) -> (any SmithyDocument)? {
+        if schema.type == .member {
+            return schema.defaultValue ?? schema.targetSchema()?.defaultValue
+        } else {
+            return schema.defaultValue
+        }
+    }
+
+    private func resolvedTargetSchema<Target>(schema: Schema<Target>) -> Schema<Target> {
+        schema.targetSchema() ?? schema
+    }
+
+    private func resolvedName(memberSchema: any SchemaProtocol) throws -> String {
+        if respectsJSONName {
+            guard let resolvedName = memberSchema.jsonName ?? memberSchema.memberName else {
+                throw ReaderError.requiredValueNotPresent
+            }
+            return resolvedName
+        } else {
+            guard let resolvedName = memberSchema.memberName else {
+                throw ReaderError.requiredValueNotPresent
+            }
+            return resolvedName
+        }
+    }
+}

Sources/SmithyJSON/Reader/Reader.swift

@@ -6,7 +6,6 @@
 //
 
 @_spi(SmithyReadWrite) import protocol SmithyReadWrite.SmithyReader
-import protocol Smithy.SmithyDocument
 import struct Smithy.Document
 import typealias SmithyReadWrite.ReadingClosure
 import enum SmithyReadWrite.ReaderError
@@ -26,20 +25,25 @@ public final class Reader: SmithyReader {
 
     public let nodeInfo: NodeInfo
     let jsonNode: JSONNode?
+    public var respectsJSONName = false {
+        didSet { children.forEach { $0.respectsJSONName = respectsJSONName } }
+    }
     public internal(set) var children = [Reader]()
     public internal(set) weak var parent: Reader?
     public var hasContent: Bool { jsonNode != nil && jsonNode != .null }
 
     init(nodeInfo: NodeInfo, jsonObject: Any?, parent: Reader? = nil) throws {
         self.nodeInfo = nodeInfo
         self.jsonNode = try Self.jsonNode(for: jsonObject)
+        self.respectsJSONName = parent?.respectsJSONName ?? false
         self.parent = parent
         self.children = try Self.children(from: jsonObject, parent: self)
     }
 
     init(nodeInfo: NodeInfo, parent: Reader?) {
         self.nodeInfo = nodeInfo
         self.jsonNode = nil
+        self.respectsJSONName = parent?.respectsJSONName ?? false
         self.parent = parent
     }