Allow API customers to set the UnitTemperature to get either US or SI…

… (metric) results from the API
roblabs · Apr 11, 2022 · 5449a64 · 5449a64
1 parent aa648de
commit 5449a64
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Showing 2 changed files with 45 additions and 1 deletion.
diff --git a/Sources/NationalWeatherService/services/calls/NWS+Forecast.swift b/Sources/NationalWeatherService/services/calls/NWS+Forecast.swift
@@ -10,10 +10,16 @@ import Foundation
 extension NationalWeatherService {
     public typealias ForecastHandler = (Result<Forecast, Error>) -> Void
 
+    /// Allow API customers to set the [UnitTemperature](https://developer.apple.com/documentation/foundation/unittemperature)
+    /// to get ["*US customary or SI (metric) units in textual output*"](https://www.weather.gov/documentation/services-web-api#/default/gridpoint_forecast)
+    public static var units: UnitTemperature = .celsius
+
     fileprivate func loadForecast(at url: URL, then handler: @escaping ForecastHandler) {
         var components = URLComponents(url: url, resolvingAgainstBaseURL: false)!
+
+        let units: String = NationalWeatherService.units == .celsius ? "si" : "us"
         components.queryItems = [
-            URLQueryItem(name: "units", value: "si")
+            URLQueryItem(name: "units", value: units)
         ]
 
         self.load(at: components.url!, as: Forecast.self, then: handler)

diff --git a/Tests/NationalWeatherServiceTests/integration/GetForecastIntegrationTests.swift b/Tests/NationalWeatherServiceTests/integration/GetForecastIntegrationTests.swift
@@ -2,6 +2,7 @@ import XCTest
 @testable import NationalWeatherService
 
 final class GetForecastIntegrationTests: XCTestCase {
+    /// Get forecast without setting `NationalWeatherService.units`
     func testGetForecastForLocation() throws {
         let forecastExpectation = self.expectation(description: "get forecast expectation")
         nws.forecast(latitude: 47.6174, longitude: -122.2017) { result in
@@ -15,7 +16,44 @@ final class GetForecastIntegrationTests: XCTestCase {
 
         wait(for: [forecastExpectation], timeout: 5)
     }
+
+    /// Get forecast by setting `NationalWeatherService.units` to `.fahrenheit`
+    func testGetForecastFahrenheit() throws {
+        let forecastExpectation = self.expectation(description: "get forecast expectation")
+
+        NationalWeatherService.units = .fahrenheit
+        nws.forecast(latitude: 47.6174, longitude: -122.2017) { result in
+            XCTAssertSuccess(result)
+
+            let forecast = try! result.get()
+            print(forecast)
+            XCTAssertFalse(forecast.periods.isEmpty)
 
+            forecastExpectation.fulfill()
+        }
+
+        wait(for: [forecastExpectation], timeout: 5)
+    }
+
+    /// Get forecast by setting `NationalWeatherService.units` to `.celsius`
+    func testGetForecastCelsius() throws {
+        let forecastExpectation = self.expectation(description: "get forecast expectation")
+
+        NationalWeatherService.units = .celsius
+        nws.forecast(latitude: 47.6174, longitude: -122.2017) { result in
+            XCTAssertSuccess(result)
+
+            let forecast = try! result.get()
+
+            print(forecast)
+            XCTAssertFalse(forecast.periods.isEmpty)
+
+            forecastExpectation.fulfill()
+        }
+
+        wait(for: [forecastExpectation], timeout: 5)
+    }
+
     func testGetHourlyForecast() throws {
         let hourlyForecastExpectation = self.expectation(description: "get hourly forecast expectation")
         nws.hourlyForecast(latitude: 47.6174, longitude: -122.2017) { result in