Implement the API endpoint to fetch specific release by tag name (nerdishbynature#141)

* add `Get a release by tag name`

* add test case

* rename router

* format with running `SwiftFormat`

Author: 417-72KI

OctoKit/Releases.swift

@@ -76,6 +76,33 @@ public extension Octokit {
         }
     }
 
+    /// Fetches a published release with the specified tag.
+    /// - Parameters:
+    ///   - session: RequestKitURLSession, defaults to URLSession.shared()
+    ///   - owner: The user or organization that owns the repositories.
+    ///   - repository: The name of the repository.
+    ///   - tag: The specified tag
+    ///   - completion: Callback for the outcome of the fetch.
+    @discardableResult
+    func release(_ session: RequestKitURLSession = URLSession.shared,
+                 owner: String,
+                 repository: String,
+                 tag: String,
+                 completion: @escaping (_ response: Result<Release, Error>) -> Void) -> URLSessionDataTaskProtocol?
+    {
+        let router = ReleaseRouter.getReleaseByTag(configuration, owner, repository, tag)
+        return router.load(session,
+                           dateDecodingStrategy: .formatted(Time.rfc3339DateFormatter),
+                           expectedResultType: Release.self)
+        { release, error in
+            if let error = error {
+                completion(.failure(error))
+            } else if let release = release {
+                completion(.success(release))
+            }
+        }
+    }
+
     /// Creates a new release.
     /// - Parameters:
     ///   - session: RequestKitURLSession, defaults to URLSession.shared()
@@ -138,20 +165,22 @@ public extension Octokit {
 
 enum ReleaseRouter: JSONPostRouter {
     case listReleases(Configuration, String, String, Int)
+    case getReleaseByTag(Configuration, String, String, String)
     case postRelease(Configuration, String, String, String, String?, String?, String?, Bool, Bool)
     case deleteRelease(Configuration, String, String, Int)
 
     var configuration: Configuration {
         switch self {
         case let .listReleases(config, _, _, _): return config
+        case let .getReleaseByTag(config, _, _, _): return config
         case let .postRelease(config, _, _, _, _, _, _, _, _): return config
         case let .deleteRelease(config, _, _, _): return config
         }
     }
 
     var method: HTTPMethod {
         switch self {
-        case .listReleases:
+        case .listReleases, .getReleaseByTag:
             return .GET
         case .postRelease:
             return .POST
@@ -162,7 +191,7 @@ enum ReleaseRouter: JSONPostRouter {
 
     var encoding: HTTPEncoding {
         switch self {
-        case .listReleases:
+        case .listReleases, .getReleaseByTag:
             return .url
         case .postRelease:
             return .json
@@ -175,6 +204,8 @@ enum ReleaseRouter: JSONPostRouter {
         switch self {
         case let .listReleases(_, _, _, perPage):
             return ["per_page": "\(perPage)"]
+        case .getReleaseByTag:
+            return [:]
         case let .postRelease(_, _, _, tagName, targetCommitish, name, body, prerelease, draft):
             var params: [String: Any] = [
                 "tag_name": tagName,
@@ -200,6 +231,8 @@ enum ReleaseRouter: JSONPostRouter {
         switch self {
         case let .listReleases(_, owner, repo, _):
             return "repos/\(owner)/\(repo)/releases"
+        case let .getReleaseByTag(_, owner, repo, tag):
+            return "repos/\(owner)/\(repo)/releases/tags/\(tag)"
         case let .postRelease(_, owner, repo, _, _, _, _, _, _):
             return "repos/\(owner)/\(repo)/releases"
         case let .deleteRelease(_, owner, repo, releaseId):

Tests/OctoKitTests/Fixtures/release.json

@@ -0,0 +1,39 @@
+{
+    "url": "https://api.github.com/repos/octocat/Hello-World/releases/1",
+    "html_url": "https://github.com/octocat/Hello-World/releases/v1.0.0",
+    "assets_url": "https://api.github.com/repos/octocat/Hello-World/releases/1/assets",
+    "upload_url": "https://uploads.github.com/repos/octocat/Hello-World/releases/1/assets{?name,label}",
+    "tarball_url": "https://api.github.com/repos/octocat/Hello-World/tarball/v1.0.0",
+    "zipball_url": "https://api.github.com/repos/octocat/Hello-World/zipball/v1.0.0",
+    "id": 1,
+    "node_id": "MDc6UmVsZWFzZTE=",
+    "tag_name": "v1.0.0",
+    "target_commitish": "master",
+    "name": "v1.0.0 Release",
+    "body": "The changelog of this release",
+    "draft": false,
+    "prerelease": false,
+    "created_at": "2013-02-27T19:35:32Z",
+    "published_at": "2013-02-27T19:35:32Z",
+    "author": {
+        "login": "octocat",
+        "id": 1,
+        "node_id": "MDQ6VXNlcjE=",
+        "avatar_url": "https://github.com/images/error/octocat_happy.gif",
+        "gravatar_id": "",
+        "url": "https://api.github.com/users/octocat",
+        "html_url": "https://github.com/octocat",
+        "followers_url": "https://api.github.com/users/octocat/followers",
+        "following_url": "https://api.github.com/users/octocat/following{/other_user}",
+        "gists_url": "https://api.github.com/users/octocat/gists{/gist_id}",
+        "starred_url": "https://api.github.com/users/octocat/starred{/owner}{/repo}",
+        "subscriptions_url": "https://api.github.com/users/octocat/subscriptions",
+        "organizations_url": "https://api.github.com/users/octocat/orgs",
+        "repos_url": "https://api.github.com/users/octocat/repos",
+        "events_url": "https://api.github.com/users/octocat/events{/privacy}",
+        "received_events_url": "https://api.github.com/users/octocat/received_events",
+        "type": "User",
+        "site_admin": false
+    },
+    "assets": []
+}

Tests/OctoKitTests/ReleasesTests.swift

@@ -105,4 +105,29 @@ final class ReleasesTests: XCTestCase {
         XCTAssertNotNil(task)
         XCTAssertTrue(session.wasCalled)
     }
+
+    func testReleaseTagName() {
+        let session = OctoKitURLTestSession(expectedURL: "https://api.github.com/repos/octocat/Hello-World/releases/tags/v1.0.0",
+                                            expectedHTTPMethod: "GET",
+                                            jsonFile: "Fixtures/release",
+                                            statusCode: 201)
+        let task = Octokit().release(session, owner: "octocat", repository: "Hello-World", tag: "v1.0.0") {
+            switch $0 {
+            case let .success(release):
+                XCTAssertEqual(release.tagName, "v1.0.0")
+                XCTAssertEqual(release.commitish, "master")
+                XCTAssertEqual(release.name, "v1.0.0 Release")
+                XCTAssertEqual(release.body, "The changelog of this release")
+                XCTAssertFalse(release.prerelease)
+                XCTAssertFalse(release.draft)
+                XCTAssertEqual(release.tarballURL?.absoluteString, "https://api.github.com/repos/octocat/Hello-World/tarball/v1.0.0")
+                XCTAssertEqual(release.zipballURL?.absoluteString, "https://api.github.com/repos/octocat/Hello-World/zipball/v1.0.0")
+                XCTAssertEqual(release.publishedAt, Date(timeIntervalSince1970: 1361993732.0))
+            case let .failure(error):
+                XCTAssert(false, "Endpoint failed with error \(error)")
+            }
+        }
+        XCTAssertNotNil(task)
+        XCTAssertTrue(session.wasCalled)
+    }
 }