public void Dispose()
{
// Clear the cache after running each test.
AppAuthResultCache.Clear();
// Delete environment variable
Environment.SetEnvironmentVariable(Constants.TestCertUrlEnv, null);
}
public async Task GetAppAuthResultCacheTest()
{
// Create two instances of AzureServiceTokenProvider based on AzureCliAccessTokenProvider.
MockProcessManager mockProcessManager = new MockProcessManager(MockProcessManager.MockProcessManagerRequestType.Success);
AzureCliAccessTokenProvider azureCliAccessTokenProvider = new AzureCliAccessTokenProvider(mockProcessManager);
AzureServiceTokenProvider azureServiceTokenProvider = new AzureServiceTokenProvider(azureCliAccessTokenProvider);
AzureServiceTokenProvider azureServiceTokenProvider1 = new AzureServiceTokenProvider(azureCliAccessTokenProvider);
List <Task> tasks = new List <Task>();
// ManualResetEvent will enable testing of SemaphoreSlim used in AzureServiceTokenProvider.
ManualResetEvent manualResetEvent = new ManualResetEvent(false);
// Use AzureServiceTokenProviders to get tokens in parallel.
for (int i = 0; i < 5; i++)
{
Task task = Task.Run(async delegate
{
// This will prevent the next line from running, until manualResetEvent.Set() is called.
// This will ensure all GetAccessTokenAsync calls are made at once.
manualResetEvent.WaitOne();
await azureServiceTokenProvider.GetAccessTokenAsync(Constants.KeyVaultResourceId);
});
tasks.Add(task);
Task task1 = Task.Run(async delegate
{
manualResetEvent.WaitOne();
// This is using the other instance of AzureServiceTokenProvider.
await azureServiceTokenProvider1.GetAccessTokenAsync(Constants.KeyVaultResourceId);
});
tasks.Add(task1);
}
// This will cause GetAccessTokenAsync calls to be made concurrently.
manualResetEvent.Set();
await Task.WhenAll(tasks);
// Even though multiple calls are made to get token concurrently, using two different instances, the process manager should only be called once.
// This test tells us that the cache is working as intended.
Assert.Equal(1, mockProcessManager.HitCount);
// Get the token again. This will test if the cache call before semaphore use is working as intended.
for (int i = 0; i < 5; i++)
{
tasks.Add(azureServiceTokenProvider.GetAccessTokenAsync(Constants.KeyVaultResourceId));
}
await Task.WhenAll(tasks);
// The hit count should still be 1, since the token should be fetched from cache.
Assert.Equal(1, mockProcessManager.HitCount);
// Update the cache entry, to simulate token expiration. This updated token will expire in just less than 5 minutes.
// In a real scenario, the token will expire after some time.
// AppAuthResultCache should not return this, since it is about to expire.
var tokenResponse = TokenResponse.Parse(TokenHelper.GetUserTokenResponse(5 * 60 - 2));
var authResult = AppAuthenticationResult.Create(tokenResponse, TokenResponse.DateFormat.DateTimeString);
AppAuthResultCache.AddOrUpdate("ConnectionString:;Authority:;Resource:https://vault.azure.net/",
new Tuple <AppAuthenticationResult, Principal>(authResult, null));
// Get the token again.
for (int i = 0; i < 5; i++)
{
tasks.Add(azureServiceTokenProvider.GetAccessTokenAsync(Constants.KeyVaultResourceId));
}
await Task.WhenAll(tasks);
// Hit count should be 2 now, since new token should have been aquired.
Assert.Equal(2, mockProcessManager.HitCount);
}
