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Extract CodableBloomFilter package

This commit is contained in:
Justin Mazzocchi 2021-02-27 17:47:00 -08:00
parent 7327d167c3
commit a12d2eb17d
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GPG Key ID: E223E6937AAFB01C
12 changed files with 12 additions and 331 deletions
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5
CodableBloomFilter/.gitignore vendored
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@ -1,5 +0,0 @@
.DS_Store
/.build
/Packages
/*.xcodeproj
xcuserdata/

21
CodableBloomFilter/Package.swift
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@ -1,21 +0,0 @@
// swift-tools-version:5.3
import PackageDescription
let package = Package(
name: "CodableBloomFilter",
products: [
.library(
name: "CodableBloomFilter",
targets: ["CodableBloomFilter"])
],
dependencies: [],
targets: [
.target(
name: "CodableBloomFilter",
dependencies: []),
.testTarget(
name: "CodableBloomFilterTests",
dependencies: ["CodableBloomFilter"])
]
)

56
CodableBloomFilter/Sources/CodableBloomFilter/BitArray.swift
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@ -1,56 +0,0 @@
// Copyright © 2020 Metabolist. All rights reserved.
import Foundation
struct BitArray {
private var bytes: [UInt8]
init(data: Data) {
bytes = Array(data)
}
}
extension BitArray {
var bitCount: Int { bytes.count * UInt8.bitWidth }
var data: Data { Data(bytes) }
subscript(index: Int) -> Bool {
get {
let (byteIndex, mask) = Self.byteIndexAndMask(index: index)
return bytes[byteIndex] & mask > 0
}
set {
let (byteIndex, mask) = Self.byteIndexAndMask(index: index)
if newValue {
bytes[byteIndex] |= mask
} else {
bytes[byteIndex] &= ~mask
}
}
}
}
extension BitArray: Codable {
init(from decoder: Decoder) throws {
bytes = Array(try decoder.singleValueContainer().decode(Data.self))
}
func encode(to encoder: Encoder) throws {
var container = encoder.singleValueContainer()
try container.encode(Data(bytes))
}
}
private extension BitArray {
static func byteIndexAndMask(index: Int) -> (Int, UInt8) {
let (byteIndex, bitIndex) = index.quotientAndRemainder(dividingBy: UInt8.bitWidth)
let mask = UInt8(2 << (bitIndex - 1))
return (byteIndex, mask)
}
}

44
CodableBloomFilter/Sources/CodableBloomFilter/BloomFilter.swift
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@ -1,44 +0,0 @@
// Copyright © 2020 Metabolist. All rights reserved.
import Foundation
public struct BloomFilter<T: DeterministicallyHashable>: Codable {
enum CodingKeys: String, CodingKey {
case hashes
case bits = "data"
}
public let hashes: [Hash]
private var bits: BitArray
public init(hashes: Set<Hash>, byteCount: Int) {
self.init(hashes: hashes, data: Data(repeating: 0, count: byteCount))
}
public init(hashes: Set<Hash>, data: Data) {
// Sort the hashes for consistent decoding output
self.hashes = Array(hashes.sorted { $0.rawValue < $1.rawValue })
bits = BitArray(data: data)
}
}
public extension BloomFilter {
var data: Data { bits.data }
mutating func insert(_ newMember: T) {
for index in indices(newMember) {
bits[index] = true
}
}
func contains(_ member: T) -> Bool {
indices(member).allSatisfy { bits[$0] }
}
}
private extension BloomFilter {
func indices(_ member: T) -> [Int] {
hashes.map { abs($0.apply(member)) % bits.bitCount }
}
}

7
CodableBloomFilter/Sources/CodableBloomFilter/DeterministicallyHashable.swift
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@ -1,7 +0,0 @@
// Copyright © 2020 Metabolist. All rights reserved.
import Foundation
public protocol DeterministicallyHashable {
var dataForHashingDeterministically: Data { get }
}

7
CodableBloomFilter/Sources/CodableBloomFilter/Extensions/Data+DeterministicallyHashable.swift
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@ -1,7 +0,0 @@
// Copyright © 2020 Metabolist. All rights reserved.
import Foundation
extension Data: DeterministicallyHashable {
public var dataForHashingDeterministically: Data { self }
}

7
CodableBloomFilter/Sources/CodableBloomFilter/Extensions/String+DeterministicallyHashable.swift
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@ -1,7 +0,0 @@
// Copyright © 2020 Metabolist. All rights reserved.
import Foundation
extension String: DeterministicallyHashable {
public var dataForHashingDeterministically: Data { Data(utf8) }
}

49
CodableBloomFilter/Sources/CodableBloomFilter/Hash.swift
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@ -1,49 +0,0 @@
// Copyright © 2020 Metabolist. All rights reserved.
import Foundation
public enum Hash: String, Codable {
case djb232
case djb2a32
case sdbm32
case fnv132
case fnv1a32
}
extension Hash {
func apply(_ hashable: DeterministicallyHashable) -> Int {
Int(Array(hashable.dataForHashingDeterministically)
.map(UInt32.init)
.reduce(offsetBasis, hash))
}
}
// http://www.cse.yorku.ca/~oz/hash.html
// http://www.isthe.com/chongo/tech/comp/fnv/
private extension Hash {
static let fnvPrime: UInt32 = 16777619
var offsetBasis: UInt32 {
switch self {
case .djb232, .djb2a32: return 5381
case .sdbm32: return 0
case .fnv132, .fnv1a32: return 2166136261
}
}
func hash(result: UInt32, next: UInt32) -> UInt32 {
switch self {
case .djb232:
return (result << 5) &+ result &+ next
case .djb2a32:
return (result << 5) &+ result ^ next
case .sdbm32:
return next &+ (result << 6) &+ (result << 16) &- result
case .fnv132:
return (result &* Self.fnvPrime) ^ next
case .fnv1a32:
return (result ^ next) &* Self.fnvPrime
}
}
}

132
CodableBloomFilter/Tests/CodableBloomFilterTests/CodableBloomFilterTests.swift
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@ -1,132 +0,0 @@
// Copyright © 2020 Metabolist. All rights reserved.
@testable import CodableBloomFilter
import XCTest
final class CodableBloomFilterTests: XCTestCase {
func testHashes() {
XCTAssertEqual(Hash.djb232.apply("hash"), 2090320585)
XCTAssertEqual(Hash.djb2a32.apply("hash"), 2087809207)
XCTAssertEqual(Hash.sdbm32.apply("hash"), 385600046)
XCTAssertEqual(Hash.fnv132.apply("hash"), 3616638997)
XCTAssertEqual(Hash.fnv1a32.apply("hash"), 3469047761)
}
func testContains() throws {
var sut = BloomFilter<String>(hashes: [.sdbm32, .djb232], byteCount: 8)
sut.insert("lol")
sut.insert("ok")
XCTAssert(sut.contains("lol"))
XCTAssert(sut.contains("ok"))
XCTAssertFalse(sut.contains("wtf"))
XCTAssertFalse(sut.contains("no"))
}
func testData() throws {
var sut = BloomFilter<String>(hashes: [.sdbm32, .djb232], byteCount: 8)
sut.insert("lol")
sut.insert("ok")
XCTAssertEqual(sut.data, Data([0, 16, 0, 0, 0, 2, 0, 144]))
}
func testFromData() throws {
let sut = BloomFilter<String>(hashes: [.sdbm32, .djb232], data: Data([0, 16, 0, 0, 0, 2, 0, 144]))
XCTAssert(sut.contains("lol"))
XCTAssert(sut.contains("ok"))
XCTAssertFalse(sut.contains("wtf"))
XCTAssertFalse(sut.contains("no"))
}
func testCoding() throws {
var sut = BloomFilter<String>(hashes: [.sdbm32, .djb232], byteCount: 8)
let expectedData = Data(#"{"data":"ABAAAAACAJA=","hashes":["djb232","sdbm32"]}"#.utf8)
sut.insert("lol")
sut.insert("ok")
let encoder = JSONEncoder()
encoder.outputFormatting = .sortedKeys
let data = try encoder.encode(sut)
XCTAssertEqual(data, expectedData)
let decoded = try JSONDecoder().decode(BloomFilter<String>.self, from: data)
XCTAssert(decoded.contains("lol"))
XCTAssert(decoded.contains("ok"))
XCTAssertFalse(decoded.contains("wtf"))
XCTAssertFalse(decoded.contains("no"))
}
func testInvalidHash() throws {
let invalidData = Data(#"{"data":"ABAAAAACAJA=","hashes":["djb232","invalid"]}"#.utf8)
XCTAssertThrowsError(try JSONDecoder().decode(BloomFilter<String>.self, from: invalidData)) {
guard case DecodingError.dataCorrupted = $0 else {
XCTFail("Expected data corrupted error")
return
}
}
}
func testDataEncodingStrategy() throws {
var sut = BloomFilter<String>(hashes: [.sdbm32, .djb232], byteCount: 8)
let expectedData = Data(#"{"data":"0010000000020090","hashes":["djb232","sdbm32"]}"#.utf8)
sut.insert("lol")
sut.insert("ok")
let encoder = JSONEncoder()
encoder.outputFormatting = .sortedKeys
encoder.dataEncodingStrategy = .custom { data, encoder in
var container = encoder.singleValueContainer()
try container.encode(data.map { String(format: "%02.2hhx", $0) }.joined())
}
let data = try encoder.encode(sut)
XCTAssertEqual(data, expectedData)
}
func testDataDecodingStrategy() throws {
let data = Data(#"{"data":"0010000000020090","hashes":["djb232","sdbm32"]}"#.utf8)
let decoder = JSONDecoder()
decoder.dataDecodingStrategy = .custom { decoder in
let container = try decoder.singleValueContainer()
let string = try container.decode(String.self)
var bytes = [UInt8]()
var i = string.startIndex
while i != string.endIndex {
let j = string.index(i, offsetBy: 2)
guard let byte = UInt8(string[i..<j], radix: 16) else {
throw DecodingError.dataCorruptedError(in: container, debugDescription: "Invalid byte")
}
bytes.append(byte)
i = j
}
return Data(bytes)
}
let sut = try decoder.decode(BloomFilter<String>.self, from: data)
XCTAssert(sut.contains("lol"))
XCTAssert(sut.contains("ok"))
XCTAssertFalse(sut.contains("wtf"))
XCTAssertFalse(sut.contains("no"))
}
}

2
Metatext.xcodeproj/project.pbxproj
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@ -396,7 +396,6 @@
D0D2AC4C25BCD2A9003D5DF2 /* TagTableViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TagTableViewCell.swift; sourceTree = "<group>"; };
D0D2AC5225BCD2BA003D5DF2 /* TagContentConfiguration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TagContentConfiguration.swift; sourceTree = "<group>"; };
D0D2AC6625BD0484003D5DF2 /* LineChartView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LineChartView.swift; sourceTree = "<group>"; };
D0D7C013250440610039AD6F /* CodableBloomFilter */ = {isa = PBXFileReference; lastKnownFileType = folder; path = CodableBloomFilter; sourceTree = "<group>"; };
D0D93EB925D9C70400C622ED /* AutocompleteItemView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AutocompleteItemView.swift; sourceTree = "<group>"; };
D0D93EBF25D9C71D00C622ED /* AutocompleteItemContentConfiguration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AutocompleteItemContentConfiguration.swift; sourceTree = "<group>"; };
D0D93ECF25D9C9ED00C622ED /* AutocompleteItemCollectionViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AutocompleteItemCollectionViewCell.swift; sourceTree = "<group>"; };
@ -635,7 +634,6 @@
D0477F2A25C6EB90005C5368 /* Activities */,
D0C7D45224F76169001EBDBB /* Assets.xcassets */,
D0FE1C9625368A15003EF1EB /* Caches */,
D0D7C013250440610039AD6F /* CodableBloomFilter */,
D0A1F4F5252E7D2A004435BF /* Data Sources */,
D085C3BB25008DEC008A6C5E /* DB */,
D0C7D46824F76169001EBDBB /* Extensions */,

9
Metatext.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved
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@ -10,6 +10,15 @@
"version": "1.0.0"
}
},
{
"package": "CodableBloomFilter",
"repositoryURL": "https://github.com/metabolist/codable-bloom-filter.git",
"state": {
"branch": null,
"revision": "53f80465056a95253df797f1d8a9199f8b1c0543",
"version": "1.0.0"
}
},
{
"package": "CombineExpectations",
"repositoryURL": "https://github.com/groue/CombineExpectations.git",

4
ServiceLayer/Package.swift
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@ -18,7 +18,9 @@ let package = Package(
],
dependencies: [
.package(url: "https://github.com/groue/CombineExpectations.git", .upToNextMajor(from: "0.7.0")),
.package(path: "CodableBloomFilter"),
.package(name: "CodableBloomFilter",
url: "https://github.com/metabolist/codable-bloom-filter.git",
.upToNextMajor(from: "1.0.0")),
.package(path: "DB"),
.package(path: "Keychain"),
.package(path: "MastodonAPI"),