Make Swift 5.2 the minimum required version (#378)

We're applying this change across all of the NIO family of projects.

I've removed the docker files for earlier versions, and set the tools version. I've also added a brief note inside the contributing guide.

Author: Davidde94

Diff for: CONTRIBUTING.md

@@ -57,6 +57,8 @@ A good AsyncHTTPClient patch is:
 3. Documented, adding API documentation as needed to cover new functions and properties.
 4. Accompanied by a great commit message, using our commit message template.
 
+*Note* as of version 1.5.0 AsyncHTTPClient requires Swift 5.2. Earlier versions support as far back as Swift 5.0.
+
 ### Commit Message Template
 
 We require that your commit messages match our template. The easiest way to do that is to get git to help you by explicitly using the template. To do that, `cd` to the root of our repository and run:

Diff for: Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.0
+// swift-tools-version:5.2
 //===----------------------------------------------------------------------===//
 //
 // This source file is part of the AsyncHTTPClient open source project
@@ -30,13 +30,30 @@ let package = Package(
     targets: [
         .target(
             name: "AsyncHTTPClient",
-            dependencies: ["NIO", "NIOHTTP1", "NIOSSL", "NIOConcurrencyHelpers", "NIOHTTPCompression",
-                           "NIOFoundationCompat", "NIOTransportServices", "Logging", "NIOSOCKS"]
+            dependencies: [
+                .product(name: "NIO", package: "swift-nio"),
+                .product(name: "NIOHTTP1", package: "swift-nio"),
+                .product(name: "NIOSSL", package: "swift-nio-ssl"),
+                .product(name: "NIOConcurrencyHelpers", package: "swift-nio"),
+                .product(name: "NIOHTTPCompression", package: "swift-nio-extras"),
+                .product(name: "NIOFoundationCompat", package: "swift-nio"),
+                .product(name: "NIOTransportServices", package: "swift-nio-transport-services"),
+                .product(name: "Logging", package: "swift-log"),
+                .product(name: "NIOSOCKS", package: "swift-nio-extras"),
+            ]
         ),
         .testTarget(
             name: "AsyncHTTPClientTests",
-            dependencies: ["NIO", "NIOConcurrencyHelpers", "NIOSSL", "AsyncHTTPClient", "NIOFoundationCompat",
-                           "NIOTestUtils", "Logging", "NIOSOCKS"]
+            dependencies: [
+                .product(name: "NIO", package: "swift-nio"),
+                .product(name: "NIOConcurrencyHelpers", package: "swift-nio"),
+                .product(name: "NIOSSL", package: "swift-nio-ssl"),
+                "AsyncHTTPClient",
+                .product(name: "NIOFoundationCompat", package: "swift-nio"),
+                .product(name: "NIOTestUtils", package: "swift-nio"),
+                .product(name: "Logging", package: "swift-log"),
+                .product(name: "NIOSOCKS", package: "swift-nio-extras"),
+            ]
         ),
     ]
 )

Diff for: README.md

@@ -10,7 +10,7 @@ This library provides the following:
 
 ---
 
-**NOTE**: You will need [Xcode 10.2](https://itunes.apple.com/us/app/xcode/id497799835) or [Swift 5.0](https://swift.org/download/#swift-50) to try out `AsyncHTTPClient`.
+**NOTE**: You will need [Xcode 11.4](https://apps.apple.com/gb/app/xcode/id497799835?mt=12) or [Swift 5.2](https://swift.org/download/#swift-52) to try out `AsyncHTTPClient`.
 
 ---
 

Diff for: docker/Dockerfile

@@ -1,4 +1,4 @@
-ARG swift_version=5.0
+ARG swift_version=5.2
 ARG ubuntu_version=bionic
 ARG base_image=swift:$swift_version-$ubuntu_version
 FROM $base_image

Diff for: docker/docker-compose.1604.51.yaml renamed to docker/docker-compose.1604.52.yaml

@@ -3,16 +3,16 @@ version: "3"
 services:
 
   runtime-setup:
-    image: async-http-client:16.04-5.1
+    image: async-http-client:16.04-5.2
     build:
       args:
         ubuntu_version: "xenial"
-        swift_version: "5.1"
+        swift_version: "5.2"
 
   test:
-    image: async-http-client:16.04-5.1
+    image: async-http-client:16.04-5.2
     environment:
       - SANITIZER_ARG=--sanitize=thread
 
   shell:
-    image: async-http-client:16.04-5.1
+    image: async-http-client:16.04-5.2

Diff for: docker/docker-compose.1804.50.yaml

@@ -115,7 +115,7 @@ for old_tag in "$@"; do
             --input-paths "$tmpdir/api-old/$f" -input-paths "$tmpdir/api-new/$f" 2>&1 \
             > "$report" 2>&1
 
-        if ! shasum "$report" | grep -q cefc4ee5bb7bcdb7cb5a7747efa178dab3c794d5; then
+        if ! shasum "$report" | grep -q afd2a1b542b33273920d65821deddc653063c700; then
             echo ERROR
             echo >&2 "=============================="
             echo >&2 "ERROR: public API change in $f"