SimpleDependencyInjectionUnitTest.cs

// Copyright 2020, Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
using Google.Cloud.Functions.Testing;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
using System.Threading.Tasks;
using Xunit;

namespace Google.Cloud.Functions.Examples.IntegrationTests;

/// <summary>
/// Example of a unit test using a MemoryLogger. Often integration tests are
/// the simplest form of testing for functions, but MemoryLogger allows log entries
/// to be tested in unit tests by implementing ILogger.
/// </summary>
public class SimpleDependencyInjectionUnitTest
{
    [Fact]
    public async Task LogEntryIsRecorded()
    {
        var logger = new MemoryLogger<SimpleDependencyInjection.Function>();
        var function = new SimpleDependencyInjection.Function(logger);

        // Constructing the function does not create any log entries.
        Assert.Empty(logger.ListLogEntries());

        // Make a request to the function.
        var context = new DefaultHttpContext
        {
            Request = { Path = "/sample-path" }
        };
        await function.HandleAsync(context);

        var logs = logger.ListLogEntries();
        var entry = Assert.Single(logs);

        Assert.Equal(LogLevel.Information, entry.Level);
        Assert.Equal("Function called with path /sample-path", entry.Message);
    }
}