SWIFT-178 Conform various options/result types to Decodable (#269)

Author: patrickfreed

Sources/MongoSwift/MongoClient.swift

@@ -2,7 +2,7 @@ import Foundation
 import mongoc
 
 /// Options to use when creating a `MongoClient`.
-public struct ClientOptions: CodingStrategyProvider {
+public struct ClientOptions: CodingStrategyProvider, Decodable {
     /// Determines whether the client should retry supported write operations.
     public let retryWrites: Bool?
 
@@ -14,24 +14,32 @@ public struct ClientOptions: CodingStrategyProvider {
     /// be used.
     public let readConcern: ReadConcern?
 
-    /// Specifies a ReadPreference to use for the client.
-    public let readPreference: ReadPreference?
-
     /// Specifies a WriteConcern to use for the client. If one is not specified, the server's default write concern
     /// will be used.
     public let writeConcern: WriteConcern?
 
+    // swiftlint:disable redundant_optional_initialization
+
+    /// Specifies a ReadPreference to use for the client.
+    public var readPreference: ReadPreference? = nil
+
     /// Specifies the `DateCodingStrategy` to use for BSON encoding/decoding operations performed by this client and any
     /// databases or collections that derive from it.
-    public let dateCodingStrategy: DateCodingStrategy?
+    public var dateCodingStrategy: DateCodingStrategy? = nil
 
     /// Specifies the `UUIDCodingStrategy` to use for BSON encoding/decoding operations performed by this client and any
     /// databases or collections that derive from it.
-    public let uuidCodingStrategy: UUIDCodingStrategy?
+    public var uuidCodingStrategy: UUIDCodingStrategy? = nil
 
     /// Specifies the `DataCodingStrategy` to use for BSON encoding/decoding operations performed by this client and any
     /// databases or collections that derive from it.
-    public let dataCodingStrategy: DataCodingStrategy?
+    public var dataCodingStrategy: DataCodingStrategy? = nil
+
+    // swiftlint:enable redundant_optional_initialization
+
+    private enum CodingKeys: CodingKey {
+        case retryWrites, eventMonitoring, readConcern, writeConcern
+    }
 
     /// Convenience initializer allowing any/all to be omitted or optional.
     public init(eventMonitoring: Bool = false,

Sources/MongoSwift/MongoCollection+BulkWrite.swift

@@ -41,7 +41,7 @@ extension MongoCollection {
     }
 
     /// A model for a `deleteOne` operation within a bulk write.
-    public struct DeleteOneModel: WriteModel {
+    public struct DeleteOneModel: WriteModel, Decodable {
         /// A `Document` representing the match criteria.
         public let filter: Document
 
@@ -78,7 +78,7 @@ extension MongoCollection {
     }
 
     /// A model for a `deleteMany` operation within a bulk write.
-    public struct DeleteManyModel: WriteModel {
+    public struct DeleteManyModel: WriteModel, Decodable {
         /// A `Document` representing the match criteria.
         public let filter: Document
 
@@ -115,7 +115,7 @@ extension MongoCollection {
     }
 
     /// A model for an `insertOne` operation within a bulk write.
-    public struct InsertOneModel: WriteModel {
+    public struct InsertOneModel: WriteModel, Decodable {
         /// The `CollectionType` to insert.
         public let document: CollectionType
 
@@ -158,7 +158,7 @@ extension MongoCollection {
     }
 
     /// A model for a `replaceOne` operation within a bulk write.
-    public struct ReplaceOneModel: WriteModel {
+    public struct ReplaceOneModel: WriteModel, Decodable {
         /// A `Document` representing the match criteria.
         public let filter: Document
 
@@ -216,7 +216,7 @@ extension MongoCollection {
     }
 
     /// A model for an `updateOne` operation within a bulk write.
-    public struct UpdateOneModel: WriteModel {
+    public struct UpdateOneModel: WriteModel, Decodable {
         /// A `Document` representing the match criteria.
         public let filter: Document
 
@@ -278,7 +278,7 @@ extension MongoCollection {
     }
 
     /// A model for an `updateMany` operation within a bulk write.
-    public struct UpdateManyModel: WriteModel {
+    public struct UpdateManyModel: WriteModel, Decodable {
         /// A `Document` representing the match criteria.
         public let filter: Document
 
@@ -418,7 +418,7 @@ public class BulkWriteOperation: Operation {
 }
 
 /// Options to use when performing a bulk write operation on a `MongoCollection`.
-public struct BulkWriteOptions: Encodable {
+public struct BulkWriteOptions: Codable {
     /// If `true`, allows the write to opt-out of document level validation.
     public let bypassDocumentValidation: Bool?
 
@@ -454,7 +454,7 @@ public struct BulkWriteOptions: Encodable {
 }
 
 /// The result of a bulk write operation on a `MongoCollection`.
-public struct BulkWriteResult {
+public struct BulkWriteResult: Decodable {
     /// Number of documents deleted.
     public let deletedCount: Int
 
@@ -476,6 +476,37 @@ public struct BulkWriteResult {
     /// Map of the index of the operation to the id of the upserted document.
     public let upsertedIds: [Int: BSONValue]
 
+    private enum CodingKeys: CodingKey {
+        case deletedCount, insertedCount, insertedIds, matchedCount, modifiedCount, upsertedCount, upsertedIds
+    }
+
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.container(keyedBy: CodingKeys.self)
+
+        // None of the results must be present themselves, but at least one must.
+        guard !container.allKeys.isEmpty else {
+            throw DecodingError.valueNotFound(BulkWriteResult.self,
+                                              DecodingError.Context(codingPath: decoder.codingPath,
+                                                                    debugDescription: "No results found"))
+        }
+
+        self.deletedCount = try container.decodeIfPresent(Int.self, forKey: .deletedCount) ?? 0
+        self.matchedCount = try container.decodeIfPresent(Int.self, forKey: .matchedCount) ?? 0
+        self.modifiedCount = try container.decodeIfPresent(Int.self, forKey: .modifiedCount) ?? 0
+
+        let insertedIds =
+                (try container.decodeIfPresent([Int: AnyBSONValue].self, forKey: .insertedIds) ?? [:])
+                        .mapValues { $0.value }
+        self.insertedIds = insertedIds
+        self.insertedCount = try container.decodeIfPresent(Int.self, forKey: .insertedCount) ?? insertedIds.count
+
+        let upsertedIds =
+                (try container.decodeIfPresent([Int: AnyBSONValue].self, forKey: .upsertedIds) ?? [:])
+                        .mapValues { $0.value }
+        self.upsertedIds = upsertedIds
+        self.upsertedCount = try container.decodeIfPresent(Int.self, forKey: .upsertedCount) ?? upsertedIds.count
+    }
+
     /**
      * Create a `BulkWriteResult` from a reply and map of inserted IDs.
      *

Sources/MongoSwift/MongoCollection+FindAndModify.swift

@@ -105,11 +105,11 @@ extension MongoCollection {
 }
 
 /// Indicates which document to return in a find and modify operation.
-public enum ReturnDocument {
+public enum ReturnDocument: String, Decodable {
     /// Indicates to return the document before the update, replacement, or insert occurred.
-    case before
+    case before = "Before"
     ///  Indicates to return the document after the update, replacement, or insert occurred.
-    case after
+    case after = "After"
 }
 
 /// Indicates that an options type can be represented as a `FindAndModifyOptions`
@@ -121,7 +121,7 @@ internal protocol FindAndModifyOptionsConvertible {
 }
 
 /// Options to use when executing a `findOneAndDelete` command on a `MongoCollection`.
-public struct FindOneAndDeleteOptions: FindAndModifyOptionsConvertible {
+public struct FindOneAndDeleteOptions: FindAndModifyOptionsConvertible, Decodable {
     /// Specifies a collation to use.
     public let collation: Document?
 
@@ -161,7 +161,7 @@ public struct FindOneAndDeleteOptions: FindAndModifyOptionsConvertible {
 }
 
 /// Options to use when executing a `findOneAndReplace` command on a `MongoCollection`.
-public struct FindOneAndReplaceOptions: FindAndModifyOptionsConvertible {
+public struct FindOneAndReplaceOptions: FindAndModifyOptionsConvertible, Decodable {
     /// If `true`, allows the write to opt-out of document level validation.
     public let bypassDocumentValidation: Bool?
 
@@ -218,7 +218,7 @@ public struct FindOneAndReplaceOptions: FindAndModifyOptionsConvertible {
 }
 
 /// Options to use when executing a `findOneAndUpdate` command on a `MongoCollection`.
-public struct FindOneAndUpdateOptions: FindAndModifyOptionsConvertible {
+public struct FindOneAndUpdateOptions: FindAndModifyOptionsConvertible, Decodable {
     /// A set of filters specifying to which array elements an update should apply.
     public let arrayFilters: [Document]?
 

Sources/MongoSwift/MongoCollection+Read.swift

@@ -138,7 +138,7 @@ extension MongoCollection {
 }
 
 /// An index to "hint" or force MongoDB to use when performing a query.
-public enum Hint: Encodable {
+public enum Hint: Codable {
     /// Specifies an index to use by its name.
     case indexName(String)
     /// Specifies an index to use by a specification `Document` containing the index key(s).
@@ -153,10 +153,19 @@ public enum Hint: Encodable {
             try container.encode(doc)
         }
     }
+
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        if let str = try? container.decode(String.self) {
+            self = .indexName(str)
+        } else {
+            self = .indexSpec(try container.decode(Document.self))
+        }
+    }
 }
 
 /// Options to use when executing an `aggregate` command on a `MongoCollection`.
-public struct AggregateOptions: Encodable {
+public struct AggregateOptions: Codable {
     /// Enables writing to temporary files. When set to true, aggregation stages
     /// can write data to the _tmp subdirectory in the dbPath directory.
     public let allowDiskUse: Bool?
@@ -184,8 +193,10 @@ public struct AggregateOptions: Encodable {
     /// A `ReadConcern` to use in read stages of this operation.
     public let readConcern: ReadConcern?
 
+    // swiftlint:disable redundant_optional_initialization
     /// A ReadPreference to use for this operation.
-    public let readPreference: ReadPreference?
+    public var readPreference: ReadPreference? = nil
+    // swiftlint:enable redundant_optional_initialization
 
     /// A `WriteConcern` to use in `$out` stages of this operation.
     public let writeConcern: WriteConcern?
@@ -265,7 +276,7 @@ public enum CursorType {
 }
 
 /// Options to use when executing a `find` command on a `MongoCollection`.
-public struct FindOptions: Encodable {
+public struct FindOptions: Codable {
     /// Get partial results from a mongos if some shards are down (instead of throwing an error).
     public let allowPartialResults: Bool?
 
@@ -278,9 +289,6 @@ public struct FindOptions: Encodable {
     /// Attaches a comment to the query.
     public let comment: String?
 
-    /// Indicates the type of cursor to use. This value includes both the tailable and awaitData options.
-    public let cursorType: CursorType?
-
     /// If a `CursorType` is provided, indicates whether it is `.tailable` or .`tailableAwait`.
     private let tailable: Bool?
 
@@ -332,8 +340,15 @@ public struct FindOptions: Encodable {
     /// A ReadConcern to use for this operation.
     public let readConcern: ReadConcern?
 
+    // swiftlint:disable redundant_optional_initialization
+
     /// A ReadPreference to use for this operation.
-    public let readPreference: ReadPreference?
+    public var readPreference: ReadPreference? = nil
+
+    /// Indicates the type of cursor to use. This value includes both the tailable and awaitData options.
+    public var cursorType: CursorType? = nil
+
+    // swiftlint:enable redundant_optional_initialization
 
     /// Convenience initializer allowing any/all parameters to be omitted or optional.
     public init(allowPartialResults: Bool? = nil,

Sources/MongoSwift/MongoCollection+Write.swift

@@ -233,7 +233,7 @@ private extension BulkWriteOptionsConvertible {
 // Write command options structs
 
 /// Options to use when executing an `insertOne` command on a `MongoCollection`.
-public struct InsertOneOptions: Encodable, BulkWriteOptionsConvertible {
+public struct InsertOneOptions: Codable, BulkWriteOptionsConvertible {
     /// If true, allows the write to opt-out of document level validation.
     public let bypassDocumentValidation: Bool?
 
@@ -251,7 +251,7 @@ public struct InsertOneOptions: Encodable, BulkWriteOptionsConvertible {
 public typealias InsertManyOptions = BulkWriteOptions
 
 /// Options to use when executing an `update` command on a `MongoCollection`.
-public struct UpdateOptions: Encodable, BulkWriteOptionsConvertible {
+public struct UpdateOptions: Codable, BulkWriteOptionsConvertible {
     /// A set of filters specifying to which array elements an update should apply.
     public let arrayFilters: [Document]?
 
@@ -282,7 +282,7 @@ public struct UpdateOptions: Encodable, BulkWriteOptionsConvertible {
 }
 
 /// Options to use when executing a `replace` command on a `MongoCollection`.
-public struct ReplaceOptions: Encodable, BulkWriteOptionsConvertible {
+public struct ReplaceOptions: Codable, BulkWriteOptionsConvertible {
     /// If true, allows the write to opt-out of document level validation.
     public let bypassDocumentValidation: Bool?
 
@@ -308,7 +308,7 @@ public struct ReplaceOptions: Encodable, BulkWriteOptionsConvertible {
 }
 
 /// Options to use when executing a `delete` command on a `MongoCollection`.
-public struct DeleteOptions: Encodable, BulkWriteOptionsConvertible {
+public struct DeleteOptions: Codable, BulkWriteOptionsConvertible {
     /// Specifies a collation.
     public let collation: Document?
 
@@ -328,7 +328,11 @@ public struct DeleteOptions: Encodable, BulkWriteOptionsConvertible {
 // Write command results structs
 
 /// The result of an `insertOne` command on a `MongoCollection`.
-public struct InsertOneResult {
+public struct InsertOneResult: Decodable {
+    private enum CodingKeys: String, CodingKey {
+        case insertedId
+    }
+
     /// The identifier that was inserted. If the document doesn't have an identifier, this value
     /// will be generated and added to the document before insertion.
     public let insertedId: BSONValue
@@ -342,6 +346,12 @@ public struct InsertOneResult {
         }
         self.insertedId = id
     }
+
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.container(keyedBy: CodingKeys.self)
+        let abv = try container.decode(AnyBSONValue.self, forKey: .insertedId)
+        self.insertedId = abv.value
+    }
 }
 
 /// The result of a multi-document insert operation on a `MongoCollection`.