Migrate to GitHub Actions

Migrate CI to use GitHub Actions.

Motivation:

To migrate to GitHub actions and centralised infrastructure.

Modifications:

Changes of note:
* Raise minimum Swift version to 5.9
* Migrate benchmarks from swift-distributed-tracing and adopt
  package-benchmark
* Adopt swift-format using rules from SwiftNIO
* Remove scripts and docker files which are no longer needed

Result:

GitHub Actions CI in parity with old CI plus benchmarks CI.

.editorconfig

@@ -0,0 +1,8 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true

.github/release.yml

@@ -0,0 +1,14 @@
+changelog:
+  categories:
+    - title: SemVer Major
+      labels:
+        - ⚠️ semver/major
+    - title: SemVer Minor
+      labels:
+        - semver/minor
+    - title: SemVer Patch
+      labels:
+        - semver/patch
+    - title: Other Changes
+      labels:
+        - semver/none

.github/workflows/main.yml

@@ -0,0 +1,25 @@
+name: Main
+
+on:
+  push:
+    branches: [main]
+  schedule:
+    - cron: "0 8,20 * * *"
+
+jobs:
+  unit-tests:
+    name: Unit tests
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
+    with:
+      linux_5_9_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error -Xswiftc -require-explicit-sendable"
+      linux_nightly_6_0_arguments_override: "--explicit-target-dependency-import-check error -Xswiftc -require-explicit-sendable"
+      linux_nightly_main_arguments_override: "--explicit-target-dependency-import-check error -Xswiftc -require-explicit-sendable"
+
+  benchmarks:
+    name: Benchmarks
+    # Workaround https://github.com/nektos/act/issues/1875
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
+    with:
+      benchmark_package_path: "Benchmarks"

.github/workflows/pull_request.yml

@@ -0,0 +1,37 @@
+name: PR
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+
+jobs:
+  soundness:
+    name: Soundness
+    uses: swiftlang/github-workflows/.github/workflows/soundness.yml@main
+    with:
+      license_header_check_project_name: "Swift Service Context"
+
+  unit-tests:
+    name: Unit tests
+    uses: apple/swift-nio/.github/workflows/unit_tests.yml@main
+    with:
+      linux_5_9_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_5_10_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+      linux_6_0_arguments_override: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error -Xswiftc -require-explicit-sendable"
+      linux_nightly_6_0_arguments_override: "--explicit-target-dependency-import-check error -Xswiftc -require-explicit-sendable"
+      linux_nightly_main_arguments_override: "--explicit-target-dependency-import-check error -Xswiftc -require-explicit-sendable"
+
+  benchmarks:
+    name: Benchmarks
+    uses: apple/swift-nio/.github/workflows/benchmarks.yml@main
+    with:
+      benchmark_package_path: "Benchmarks"
+
+  cxx-interop:
+    name: Cxx interop
+    uses: apple/swift-nio/.github/workflows/cxx_interop.yml@main
+
+  swift-6-language-mode:
+    name: Swift 6 Language Mode
+    uses: apple/swift-nio/.github/workflows/swift_6_language_mode.yml@main
+    if: false  # Disabled for now.

.github/workflows/pull_request_label.yml

@@ -0,0 +1,18 @@
+name: PR label
+
+on:
+  pull_request:
+    types: [labeled, unlabeled, opened, reopened, synchronize]
+
+jobs:
+  semver-label-check:
+    name: Semantic Version label check
+    runs-on: ubuntu-latest
+    timeout-minutes: 1
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+      - name: Check for Semantic Version label
+        uses: apple/swift-nio/.github/actions/pull_request_semver_label_checker@main

.licenseignore

@@ -0,0 +1,35 @@
+.gitignore
+**/.gitignore
+.licenseignore
+.gitattributes
+.git-blame-ignore-revs
+.mailfilter
+.mailmap
+.spi.yml
+.swift-format
+.editorconfig
+.github/*
+*.md
+*.txt
+*.yml
+*.yaml
+*.json
+Package.swift
+**/Package.swift
+Package@-*.swift
+**/Package@-*.swift
+Package.resolved
+**/Package.resolved
+Makefile
+*.modulemap
+**/*.modulemap
+**/*.docc/*
+*.xcprivacy
+**/*.xcprivacy
+*.symlink
+**/*.symlink
+Dockerfile
+**/Dockerfile
+Snippets/*
+dev/git.commit.template
+.unacceptablelanguageignore

.swift-format

@@ -0,0 +1,68 @@
+{
+  "version" : 1,
+  "indentation" : {
+    "spaces" : 4
+  },
+  "tabWidth" : 4,
+  "fileScopedDeclarationPrivacy" : {
+    "accessLevel" : "private"
+  },
+  "spacesAroundRangeFormationOperators" : false,
+  "indentConditionalCompilationBlocks" : false,
+  "indentSwitchCaseLabels" : false,
+  "lineBreakAroundMultilineExpressionChainComponents" : false,
+  "lineBreakBeforeControlFlowKeywords" : false,
+  "lineBreakBeforeEachArgument" : true,
+  "lineBreakBeforeEachGenericRequirement" : true,
+  "lineLength" : 120,
+  "maximumBlankLines" : 1,
+  "respectsExistingLineBreaks" : true,
+  "prioritizeKeepingFunctionOutputTogether" : true,
+  "noAssignmentInExpressions" : {
+    "allowedFunctions" : [
+      "XCTAssertNoThrow",
+      "XCTAssertThrowsError"
+    ]
+  },
+  "rules" : {
+    "AllPublicDeclarationsHaveDocumentation" : false,
+    "AlwaysUseLiteralForEmptyCollectionInit" : false,
+    "AlwaysUseLowerCamelCase" : false,
+    "AmbiguousTrailingClosureOverload" : true,
+    "BeginDocumentationCommentWithOneLineSummary" : false,
+    "DoNotUseSemicolons" : true,
+    "DontRepeatTypeInStaticProperties" : true,
+    "FileScopedDeclarationPrivacy" : true,
+    "FullyIndirectEnum" : true,
+    "GroupNumericLiterals" : true,
+    "IdentifiersMustBeASCII" : true,
+    "NeverForceUnwrap" : false,
+    "NeverUseForceTry" : false,
+    "NeverUseImplicitlyUnwrappedOptionals" : false,
+    "NoAccessLevelOnExtensionDeclaration" : true,
+    "NoAssignmentInExpressions" : true,
+    "NoBlockComments" : true,
+    "NoCasesWithOnlyFallthrough" : true,
+    "NoEmptyTrailingClosureParentheses" : true,
+    "NoLabelsInCasePatterns" : true,
+    "NoLeadingUnderscores" : false,
+    "NoParensAroundConditions" : true,
+    "NoVoidReturnOnFunctionSignature" : true,
+    "OmitExplicitReturns" : true,
+    "OneCasePerLine" : true,
+    "OneVariableDeclarationPerLine" : true,
+    "OnlyOneTrailingClosureArgument" : true,
+    "OrderedImports" : true,
+    "ReplaceForEachWithForLoop" : true,
+    "ReturnVoidInsteadOfEmptyTuple" : true,
+    "UseEarlyExits" : false,
+    "UseExplicitNilCheckInConditions" : false,
+    "UseLetInEveryBoundCaseVariable" : false,
+    "UseShorthandTypeNames" : true,
+    "UseSingleLinePropertyGetter" : false,
+    "UseSynthesizedInitializer" : false,
+    "UseTripleSlashForDocumentationComments" : true,
+    "UseWhereClausesInForLoops" : false,
+    "ValidateDocumentationComments" : false
+  }
+}

Benchmarks/.gitignore

@@ -0,0 +1 @@
+.build/

Benchmarks/Benchmarks/ServiceContextBenchmarks/Benchmarks.swift

@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift Service Context open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift Service Context project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift Service Context project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Benchmark
+
+let benchmarks = {
+    let defaultMetrics: [BenchmarkMetric] = [
+        .mallocCountTotal
+    ]
+
+    Benchmark(
+        "PassAroundStaticStringsSmall",
+        configuration: .init(
+            metrics: defaultMetrics,
+            scalingFactor: .mega,
+            maxDuration: .seconds(10_000_000),
+            maxIterations: 10
+        )
+    ) { benchmark in
+        runPassAroundStaticStringsSmall(
+            iterations: benchmark.scaledIterations.upperBound
+        )
+    }
+
+    Benchmark(
+        "PassAroundStaticStringsLarge",
+        configuration: .init(
+            metrics: defaultMetrics,
+            scalingFactor: .mega,
+            maxDuration: .seconds(10_000_000),
+            maxIterations: 10
+        )
+    ) { benchmark in
+        runPassAroundStaticStringsLarge(
+            iterations: benchmark.scaledIterations.upperBound
+        )
+    }
+}

Benchmarks/Benchmarks/ServiceContextBenchmarks/PassAroundStaticStrings.swift

@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift Service Context open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift Service Context project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift Service Context project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift Distributed Tracing open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift Distributed Tracing project
+// authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Benchmark
+import ServiceContextModule
+
+func runPassAroundStaticStringsSmall(iterations: Int) {
+    var context = ServiceContext.topLevel
+    // static allocated strings
+    context[StringKey1.self] = "one"
+    context[StringKey2.self] = "two"
+    context[StringKey3.self] = "three"
+
+    for _ in 0..<iterations {
+        let res = take1(context: context)
+        precondition(res == 42)
+    }
+}
+
+func runPassAroundStaticStringsLarge(iterations: Int) {
+    var context = ServiceContext.topLevel
+    // static allocated strings
+    context[StringKey1.self] = String(repeating: "a", count: 30)
+    context[StringKey2.self] = String(repeating: "b", count: 12)
+    context[StringKey3.self] = String(repeating: "c", count: 20)
+
+    for _ in 0..<iterations {
+        let res = take1(context: context)
+        precondition(res == 42)
+    }
+}