Better response error handling (#32)

joshuawright11 · Nov 21, 2023 · b9bdc84 · b9bdc84
1 parent f591dab
commit b9bdc84
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Showing 7 changed files with 54 additions and 44 deletions.
diff --git a/Papyrus/URLSession+Papyrus.swift b/Papyrus/URLSession+Papyrus.swift
@@ -21,7 +21,7 @@ extension URLSession: HTTPService {
         request.httpMethod = method
         request.httpBody = body
         request.allHTTPHeaderFields = headers
-        return _Request(request: request)
+        return request
     }
 
     public func request(_ req: Request) async -> Response {
@@ -51,21 +51,23 @@ extension URLSession: HTTPService {
 // MARK: `Response` Conformance
 
 extension Response {
-    public var urlRequest: URLRequest { (self as! _Response).request }
-    public var urlResponse: URLResponse? { (self as! _Response).response }
+    public var urlRequest: URLRequest { (self as! _Response).urlRequest }
+    public var urlResponse: URLResponse? { (self as! _Response).urlResponse }
 }
 
 private struct _Response: Response {
-    let request: URLRequest
-    let response: URLResponse?
+    let urlRequest: URLRequest
+    let urlResponse: URLResponse?
+
+    var request: Request? { urlRequest }
     let error: Error?
     let body: Data?
     let headers: [String: String]?
     var statusCode: Int? { (urlResponse as? HTTPURLResponse)?.statusCode }
 
     init(request: URLRequest, response: URLResponse?, error: Error?, body: Data?) {
-        self.request = request
-        self.response = response
+        self.urlRequest = request
+        self.urlResponse = response
         self.error = error
         self.body = body
         let headerPairs = (response as? HTTPURLResponse)?
@@ -89,30 +91,23 @@ private struct _Response: Response {
 
 extension Request {
     public var urlRequest: URLRequest {
-        (self as! _Request).request
+        (self as! URLRequest)
     }
 }
 
-private struct _Request: Request {
-    var request: URLRequest
-
-    public var url: URL {
-        get { request.url! }
-        set { request.url = newValue }
-    }
-
+extension URLRequest: Request {
     public var body: Data? {
-        get { request.httpBody }
-        set { request.httpBody = newValue }
+        get { httpBody }
+        set { httpBody = newValue }
     }
 
     public var method: String {
-        get { request.httpMethod ?? "" }
-        set { request.httpMethod = newValue }
+        get { httpMethod ?? "" }
+        set { httpMethod = newValue }
     }
 
     public var headers: [String: String] {
-        get { request.allHTTPHeaderFields ?? [:] }
-        set { request.allHTTPHeaderFields = newValue }
+        get { allHTTPHeaderFields ?? [:] }
+        set { allHTTPHeaderFields = newValue }
     }
 }
diff --git a/PapyrusAlamofire/Alamofire+Papyrus.swift b/PapyrusAlamofire/Alamofire+Papyrus.swift
@@ -19,7 +19,7 @@ extension Session: HTTPService {
         request.httpMethod = method
         request.httpBody = body
         request.allHTTPHeaderFields = headers
-        return _Request(request: request)
+        return request
     }
 
     public func request(_ req: PapyrusCore.Request) async -> Response {
@@ -42,6 +42,8 @@ extension Response {
 }
 
 extension DataResponse: Response {
+    @_implements(Response, request)
+    public var _request: PapyrusCore.Request? { request }
     public var body: Data? { data }
     public var headers: [String : String]? { response?.headers.dictionary }
     public var statusCode: Int? { response?.statusCode }
@@ -55,30 +57,23 @@ extension DataResponse: Response {
 
 extension PapyrusCore.Request {
     public var urlRequest: URLRequest {
-        (self as! _Request).request
+        (self as! URLRequest)
     }
 }
 
-private struct _Request: PapyrusCore.Request {
-    var request: URLRequest
-
-    public var url: URL {
-        get { request.url! }
-        set { request.url = newValue }
-    }
-
+extension URLRequest: PapyrusCore.Request {
     public var body: Data? {
-        get { request.httpBody }
-        set { request.httpBody = newValue }
+        get { httpBody }
+        set { httpBody = newValue }
     }
 
     public var method: String {
-        get { request.httpMethod ?? "" }
-        set { request.httpMethod = newValue }
+        get { httpMethod ?? "" }
+        set { httpMethod = newValue }
     }
 
     public var headers: [String: String] {
-        get { request.allHTTPHeaderFields ?? [:] }
-        set { request.allHTTPHeaderFields = newValue }
+        get { allHTTPHeaderFields ?? [:] }
+        set { allHTTPHeaderFields = newValue }
     }
 }
diff --git a/PapyrusCore/Sources/PapyrusError.swift b/PapyrusCore/Sources/PapyrusError.swift
@@ -2,11 +2,19 @@
 public struct PapyrusError: Error {
     /// What went wrong.
     public let message: String
+    /// Error related request.
+    public let request: Request?
+    /// Error related response.
+    public let response: Response?
 
     /// Create an error with the specified message.
     ///
     /// - Parameter message: What went wrong.
-    public init(_ message: String) {
+    /// - Parameter request: Error related request.
+    /// - Parameter response: Error related response.
+    public init(_ message: String, _ request: Request? = nil, _ response: Response? = nil) {
         self.message = message
+        self.request = request
+        self.response = response
     }
 }
diff --git a/PapyrusCore/Sources/Request.swift b/PapyrusCore/Sources/Request.swift
@@ -1,7 +1,7 @@
 import Foundation
 
 public protocol Request {
-    var url: URL { get set }
+    var url: URL? { get set }
     var method: String { get set }
     var headers: [String: String] { get set }
     var body: Data? { get set }

diff --git a/PapyrusCore/Sources/Response.swift b/PapyrusCore/Sources/Response.swift
@@ -1,6 +1,7 @@
 import Foundation
 
 public protocol Response {
+    var request: Request? { get }
     var body: Data? { get }
     var headers: [String: String]? { get }
     var statusCode: Int? { get }
@@ -12,7 +13,7 @@ extension Response {
     @discardableResult
     public func validate() throws -> Self {
         if let error { throw error }
-        if let statusCode, !(200..<300).contains(statusCode) { throw PapyrusError("Unsuccessful status code: \(statusCode).") }
+        if let statusCode, !(200..<300).contains(statusCode) { throw makePapyrusError(with: "Unsuccessful status code: \(statusCode).") }
         return self
     }
 
@@ -22,19 +23,23 @@ extension Response {
 
     public func decode(_ type: Data.Type = Data.self, using decoder: ResponseDecoder) throws -> Data {
         guard let body = try decode(Data?.self, using: decoder) else {
-            throw PapyrusError("Unable to return the body of a `Response`; the body was nil.")
+            throw makePapyrusError(with: "Unable to return the body of a `Response`; the body was nil.")
         }
 
         return body
     }
 
     public func decode<D: Decodable>(_ type: D.Type = D.self, using decoder: ResponseDecoder) throws -> D {
-        guard let body = try validate().body else {
-            throw PapyrusError("Unable to decode `\(Self.self)` from a `Response`; body was nil.")
+        guard let body else {
+            throw makePapyrusError(with: "Unable to decode `\(Self.self)` from a `Response`; body was nil.")
         }
 
         return try decoder.decode(type, from: body)
     }
+
+    private func makePapyrusError(with message: String) -> PapyrusError {
+        PapyrusError(message, request, self)
+    }
 }
 
 extension Response where Self == ErrorResponse {
@@ -50,6 +55,7 @@ public struct ErrorResponse: Response {
         self._error = error
     }
 
+    public var request: Request? { nil }
     public var body: Data? { nil }
     public var headers: [String : String]? { nil }
     public var statusCode: Int? { nil }

diff --git a/PapyrusPlugin/Sources/APIMacro.swift b/PapyrusPlugin/Sources/APIMacro.swift
@@ -136,6 +136,7 @@ extension FunctionDeclSyntax {
 
                 return """
                     let res = try await provider.request(req)
+                    try res.validate()
                     return \(resultExpression)
                     """
             }

diff --git a/PapyrusPlugin/Tests/APIMacroTests.swift b/PapyrusPlugin/Tests/APIMacroTests.swift
@@ -98,6 +98,7 @@ final class APIMacroTests: XCTestCase {
                     var req = builder(method: "GET", path: "some/path")
                     req.addQuery("userId", value: userId)
                     let res = try await provider.request(req)
+                    try res.validate()
                     return try res.decode(String.self, using: req.responseDecoder)
                 }
 
@@ -139,6 +140,7 @@ final class APIMacroTests: XCTestCase {
                     var req = builder(method: "GET", path: "some/path")
                     req.addQuery("userId", value: userId)
                     let res = try await provider.request(req)
+                    try res.validate()
                     return try res.decode(String.self, using: req.responseDecoder)
                 }
 
@@ -177,6 +179,7 @@ final class APIMacroTests: XCTestCase {
                     var req = builder(method: "GET", path: "some/path")
                     req.addField("userId", value: userId)
                     let res = try await provider.request(req)
+                    try res.validate()
                     return try res.decode(String.self, using: req.responseDecoder)
                 }
 
@@ -222,6 +225,7 @@ final class APIMacroTests: XCTestCase {
                     req.addParameter("userId", value: userId)
                     req.addQuery("since", value: since)
                     let res = try await provider.request(req)
+                    try res.validate()
                     return try res.decode(String.self, using: req.responseDecoder)
                 }
 
@@ -268,6 +272,7 @@ final class APIMacroTests: XCTestCase {
                     req.addParameter("userId", value: userId)
                     req.addQuery("since", value: since)
                     let res = try await provider.request(req)
+                    try res.validate()
                     return try res.decode(String.self, using: req.responseDecoder)
                 }