Added KineticSession.traverse() (c8b0aad8) · Commits · kinetic-archive / kinetic-swift-lang

Kinetic/Commands/KeyRange.swift

+116 −8

Original line number	Diff line number	Diff line
		@@ -25,6 +25,7 @@ public enum Range<K : KeyType> : CustomStringConvertible{
		case From(K, Bool)
		case To(K, Bool)
		case Prefix(K)
		case Empty

		internal func build(builder: Builder, device: KineticDevice) {
		switch self {
		@@ -54,6 +55,11 @@ public enum Range<K : KeyType> : CustomStringConvertible{
		builder.range.endKey = NSData(bytes: bs, length: p.length)
		builder.range.endKeyInclusive = false
		}
		case Empty:
		builder.range.startKey = "".toData()
		builder.range.startKeyInclusive = false
		builder.range.endKey = "".toData()
		builder.range.endKeyInclusive = false
		}
		}

		@@ -72,11 +78,11 @@ public enum Range<K : KeyType> : CustomStringConvertible{
		case To(let key, true): return "Range [..'\(key)']"
		case To(let key, false): return "Range [..'\(key)')"
		case Prefix(let prefix): return "Prefix '\(prefix)'"
		case Empty: return "Empty"
		}
		}
		}


		public class GetKeyRangeCommand<K : KeyType> : ChannelCommand {

		public typealias ResponseType = KeyRangeResponse
		@@ -91,7 +97,7 @@ public class GetKeyRangeCommand<K : KeyType> : ChannelCommand {
		self.maxReturned = maxReturned
		}

		public func build(builder: Builder, device: KineticDevice) -> Int {
		public func build(builder: Builder, device: KineticDevice) -> KeyRangeContext {
		builder.header.messageType = .Getkeyrange
		self.range.build(builder, device: device)
		builder.range.reverse = self.reverse
		@@ -105,20 +111,47 @@ public class GetKeyRangeCommand<K : KeyType> : ChannelCommand {
		}
		builder.range.maxReturned = max

		return Int(max)
		return KeyRangeContext(maxReturned: Int(max),
		reverse: self.reverse,
		endKey: builder.range.endKey,
		endInclusive: builder.range.endKeyInclusive)
		}

		}

		public struct KeyRangeContext {
		internal let maxReturned: Int
		internal let reverse: Bool
		internal let endKey: NSData
		internal let endInclusive: Bool
		}

		public struct KeyRangeResponse: ChannelResponse {
		public typealias ContextType = Int
		public typealias ContextType = KeyRangeContext

		public let success: Bool
		public let error: KineticRemoteError?
		public let keys: [NSData]
		public let hasMore: Bool
		private let context: KeyRangeContext

		public var next: GetKeyRangeCommand<NSData> {
		guard self.hasMore else {
		return GetKeyRangeCommand(.Empty) }
		guard self.keys.count > 0 else {
		return GetKeyRangeCommand(.Empty) }
		// Even if there might be more, we know there isnt because we already got the last key
		guard self.keys[self.keys.count - 1] != self.context.endKey else {
		return GetKeyRangeCommand(.Empty) }

		public static func parse(raw: RawResponse, context: Int) -> KeyRangeResponse {
		return GetKeyRangeCommand(.FromTo(self.keys[self.keys.count-1],
		self.context.endKey,
		false, self.context.endInclusive),
		reverse: self.context.reverse,
		maxReturned: self.context.maxReturned)
		}

		public static func parse(raw: RawResponse, context: KeyRangeContext) -> KeyRangeResponse {
		switch raw.command.status.code {
		case .Success:
		var keys: [NSData] = []
		@@ -130,11 +163,79 @@ public struct KeyRangeResponse: ChannelResponse {
		}
		return KeyRangeResponse(success: true, error: nil,
		keys: keys,
		hasMore: keys.count == context)
		hasMore: keys.count == context.maxReturned,
		context: context )
		default:
		return KeyRangeResponse(success: false,
		error: KineticRemoteError.fromStatus(raw.command.status),
		keys: [], hasMore: false)
		keys: [], hasMore: false, context: context)
		}
		}
		}

		public class KeySequence<K: KeyType>: SequenceType {
		public typealias Generator = KeyGenerator<K>

		private let session: KineticSession
		private let range: Range<K>
		private let reverse: Bool
		private let batch: Int?

		internal init(session: KineticSession, range: Range<K>, reverse:Bool = false, batch: Int? = nil) {
		self.session = session
		self.range = range
		self.reverse = reverse
		self.batch = batch
		}

		public func generate() -> KeyGenerator<K> {
		return KeyGenerator<K>(session: session, range: self.range, reverse: self.reverse, batch: self.batch)
		}
		}

		public class KeyGenerator<K: KeyType>: GeneratorType {
		public typealias Element = NSData

		// Params
		private let session: KineticSession
		private let range: Range<K>
		private let reverse: Bool
		private let batch: Int?

		// state
		private var lastResponse: KeyRangeResponse?
		private var index: Int

		internal init(session: KineticSession, range: Range<K>, reverse:Bool = false, batch: Int? = nil) {
		self.session = session
		self.range = range
		self.reverse = reverse
		self.batch = batch
		self.index = 0

		let first = GetKeyRangeCommand(range, reverse: reverse, maxReturned: batch)
		do {
		self.lastResponse = try first.sendTo(self.session)
		} catch { /* TODO: log */ }
		}

		public func next() -> NSData? {
		if self.lastResponse == nil {
		return nil
		} else if self.index < self.lastResponse!.keys.count {
		return self.lastResponse!.keys[self.index++]
		} else if self.lastResponse!.hasMore {
		let cmd = self.lastResponse!.next
		do {
		self.lastResponse = try cmd.sendTo(self.session)
		} catch {
		// TODO: log
		self.lastResponse = nil
		}
		self.index = 0
		return self.next()
		} else {
		return nil
		}
		}
		}
		@@ -158,12 +259,19 @@ extension GetKeyRangeCommand: CustomStringConvertible {
		}

		public extension KineticSession {

		func getKeyRange<K>(range: Range<K>, reverse: Bool = false) throws -> GetKeyRangeCommand<K>.ResponseType {
		let cmd = GetKeyRangeCommand(range, reverse: reverse, maxReturned: nil)
		return try cmd.sendTo(self)
		}

		func getKeyRange<K>(range: Range<K>, reverse: Bool, maxReturned: Int) throws -> GetKeyRangeCommand<K>.ResponseType {
		let cmd = GetKeyRangeCommand(range, reverse: reverse, maxReturned: maxReturned)
		return try cmd.sendTo(self)
		}

		func traverse<K>(range: Range<K>, reverse: Bool = false, batch: Int) throws -> KeySequence<K> {
		return KeySequence(session: self, range: range, reverse: reverse, batch: batch)
		}

		}
		No newline at end of file

Kinetic/Core.swift

+7 −0

Original line number	Diff line number	Diff line
		@@ -32,21 +32,28 @@ public protocol ValueType {
		}

		extension NSData: KeyType, ValueType {

		public func toData() -> NSData { return self }

		public func toBytes() -> Bytes {
		// TODO: figure out how to do this without copying!
		var buffer = Bytes(count: self.length, repeatedValue: 0)
		self.getBytes(&buffer, length: self.length)
		return buffer
		}

		}

		extension String: KeyType, ValueType {

		public var length: Int { return self.lengthOfBytesUsingEncoding(NSUTF8StringEncoding) }

		public func toData() -> NSData {
		return NSData(data: self.dataUsingEncoding(NSUTF8StringEncoding)!)
		}

		public func toBytes() -> Bytes { return self.toUtf8() }

		}

		public class Builder {

examples/Example 2 - Basics.playground/Contents.swift

+5 −0

Original line number	Diff line number	Diff line
		@@ -53,4 +53,9 @@ try c.getKeyRange(.Prefix("demo"))
		try c.getKeyRange(.Prefix("demo"), reverse: true)
		try c.getKeyRange(.Prefix("demo"), reverse: true, maxReturned: 42)

		//: If we wish to iterate through a range of keys that might span the entire
		//: contents of the device, we can use `KineticSession.traverse()`
		let ks = try c.traverse(.From("", true), reverse: false, batch: 64)
		for k in ks { print(k.toUtf8()) }

		c.close()

examples/Example 2 - Basics.playground/contents.xcplayground

+1 −1

Original line number	Diff line number	Diff line
		<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
		<playground version='5.0' target-platform='osx' requires-full-environment='true' display-mode='rendered'>
		<playground version='5.0' target-platform='osx' requires-full-environment='true' display-mode='raw'>
		<timeline fileName='timeline.xctimeline'/>
		</playground>
		No newline at end of file