PR review and refactoring

Author: acoumb

src/Umbraco.Cms.Integrations.Authorization/Dependencies.cs

@@ -0,0 +1,12 @@
+{
+  "version": 1,
+  "isRoot": true,
+  "tools": {
+    "dotnet-ef": {
+      "version": "6.0.1",
+      "commands": [
+        "dotnet-ef"
+      ]
+    }
+  }
+}

src/Umbraco.Cms.Integrations.Authorization/Interfaces/IAuthorizationService.cs

@@ -0,0 +1,15 @@
+namespace Umbraco.Forms.Integrations.Crm.Hubspot.OAuthProxy.Configuration
+{
+    public class AppSettings
+    {
+        public string HubspotAuthUri { get; set; }
+
+        public string HubspotClientSecret { get; set; }
+
+        public string SemrushAuthUri { get; set; }
+
+        public string SemrushClientSecret { get; set; }
+
+        public string this[string propertyName] => (string) GetType().GetProperty(propertyName)?.GetValue(this, null);
+    }
+}

src/Umbraco.Cms.Integrations.Authorization/Models/Dtos/ResponseDto.cs

@@ -0,0 +1,71 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http;
+using System.Threading.Tasks;
+
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Options;
+
+using Umbraco.Forms.Integrations.Crm.Hubspot.OAuthProxy.Configuration;
+
+namespace Umbraco.Cms.Integrations.OAuthProxy.Controllers
+{
+    [ApiController]
+    public class OAuthProxyController : Controller
+    {
+        private readonly IHttpClientFactory _httpClientFactory;
+        private readonly AppSettings _appSettings;
+
+        public const string ServiceNameHeaderKey = "service_name";
+
+        private static List<string> ValidServiceNames = new List<string> {"Hubspot", "Semrush"};
+
+        public OAuthProxyController(IHttpClientFactory httpClientFactory, IOptions<AppSettings> appSettings)
+        {
+            _httpClientFactory = httpClientFactory;
+            _appSettings = appSettings.Value;
+        }
+
+        [HttpPost]
+        [Route("/oauth/v1/token")]
+        public async Task ProxyTokenRequest()
+        {
+            if (!Request.Headers.TryGetValue(ServiceNameHeaderKey, out var serviceName))
+            {
+                serviceName = "Hubspot";
+            }
+
+            if (!ValidServiceNames.Contains(serviceName))
+            {
+                throw 
+                    new InvalidOperationException($"Provided {ServiceNameHeaderKey} header value of {serviceName} is not supported");
+            }
+
+            var httpClient = _httpClientFactory.CreateClient($"{serviceName}Token");
+
+            var response =
+                await httpClient.PostAsync(GetAuthUri(serviceName), GetContent(Request.Form, serviceName));
+            var content = await response.Content.ReadAsStringAsync();
+
+            Response.StatusCode = (int)response.StatusCode;
+
+            Response.ContentType = response.Content.Headers.ContentType?.ToString();
+            Response.ContentLength = response.Content.Headers.ContentLength;
+
+            await Response.WriteAsync(content);
+        }
+
+        private HttpContent GetContent(IFormCollection form, string serviceName)
+        {
+            var dictionary = form.ToDictionary(x => x.Key, x => x.Value.ToString());
+            dictionary.Add("client_secret", GetClientSecret(serviceName));
+            return new FormUrlEncodedContent(dictionary);
+        }
+
+        private string GetClientSecret(string serviceName) => _appSettings[$"{serviceName}ClientSecret"];
+
+        private string GetAuthUri(string serviceName) => _appSettings[$"{serviceName}AuthUri"];
+    }
+}