01-default-http-trigger.cs

public static class DefaultHttpTrigger
{
    [FunctionName("DefaultHttpTrigger")]

    [OpenApiOperation(operationId: "greeting", tags: new[] { "greeting" }, Summary = "Greetings", Description = "This shows a welcome message.", Visibility = OpenApiVisibilityType.Important)]
    [OpenApiSecurity("function_key", SecuritySchemeType.ApiKey, Name = "code", In = OpenApiSecurityLocationType.Query)]
    [OpenApiParameter("name", Type = typeof(string), In = ParameterLocation.Query, Visibility = OpenApiVisibilityType.Important)]
    [OpenApiResponseWithBody(statusCode: HttpStatusCode.OK, contentType: "application/json", bodyType: typeof(Greeting), Summary = "The response", Description = "This returns the response")]

    public static async Task<IActionResult> Run(
        [HttpTrigger(AuthorizationLevel.Function, "get", Route = "greetings")] HttpRequest req,
        ILogger log)
    {
        log.LogInformation("C# HTTP trigger function processed a request.");

        string name = req.Query["name"];
        var message = $"Hello, {name}!";
        var instance = new Greeting() { Message = message };

        var result = new OkObjectResult(instance);

        return await Task.FromResult(result).ConfigureAwait(false);
    }
}

public class Greeting
{
    public string Message { get; set; }
}

02-openapi-v3.json

{
  "openapi": "3.0.1",
  "info": {
    "title": "OpenAPI Document on Azure Functions",
    "version": "1.0.0"
  },
  "servers": [
    {
      "url": "http://localhost:7071/api"
    }
  ],
  "paths": {
    "/greetings": {
      "get": {
        "tags": [
          "greeting"
        ],
        "summary": "Greetings",
        "description": "This shows a welcome message.",
        "operationId": "greeting",
        "parameters": [
          {
            "name": "name",
            "in": "query",
            "schema": {
              "type": "string"
            },
            "x-ms-visibility": "important"
          }
        ],
        "responses": {
          "200": {
            "description": "This returns the response",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/greeting"
                }
              }
            },
            "x-ms-summary": "The response"
          }
        },
        "security": [
          {
            "function_key": [ ]
          }
        ],
        "x-ms-visibility": "important"
      }
    }
  },
  "components": {
    "schemas": {
      "greeting": {
        "type": "object",
        "properties": {
          "message": {
            "type": "string"
          }
        }
      }
    },
    "securitySchemes": {
      "function_key": {
        "type": "apiKey",
        "name": "code",
        "in": "query"
      }
    }
  }
}

03-func-start.sh

func start

04-func-start-bg.sh

# Bash
func start &
bg

05-func-start.ps1

# PowerShell
Start-Process -NoNewWindow func start

06-default-http-trigger-tests.cs

[TestClass]
public class DefaultHttpTriggerTests
{
    private HttpClient _http;

    [TestInitialize]
    public void Initialize()
    {
        this._http = new HttpClient();
    }

    [TestCleanup]
    public void Cleanup()
    {
        this._http.Dispose();
    }

    [TestMethod]
    public async Task Given_OpenApiUrl_When_Endpoint_Invoked_Then_It_Should_Return_Title()
    {
        // Arrange
        var requestUri = "http://localhost:7071/api/openapi/v3.json";

        // Act
        var response = await this._http.GetStringAsync(requestUri).ConfigureAwait(false);
        var doc = JsonConvert.DeserializeObject<OpenApiDocument>(response);

        // Assert
        doc.Should().NotBeNull();
        doc.Info.Title.Should().Be("OpenAPI Document on Azure Functions");
        doc.Components.Schemas.Should().ContainKey("greeting");

        var schema = doc.Components.Schemas["greeting"];
        schema.Type.Should().Be("object");
        schema.Properties.Should().ContainKey("message");

        var property = schema.Properties["message"];
        property.Type.Should().Be("string");
    }
}

07-dotnet-test.sh

dotnet test

08-build-1.yaml

jobs:
  build_and_test:
    name: Build and test
    strategy:
      matrix:
        os: [ 'windows-latest', 'macos-latest', 'ubuntu-latest' ]

    runs-on: ${{ matrix.os }}

08-build-2.yaml

    steps:
    - name: Checkout the repository
      uses: actions/checkout@v2

    - name: Setup Azure Functions Core Tools
      shell: pwsh
      run: |
        npm install -g azure-functions-core-tools@3 --unsafe-perm true

08-build-3.yaml

    - name: Setup .NET SDK 3.1 LTS
      uses: actions/setup-dotnet@v1
      with:
        dotnet-version: '3.1.x'

08-build-4.yaml

    - name: Test function app (Non-Windows)
      if: matrix.os != 'windows-latest'
      shell: pwsh
      run: |
        dir

        $rootDir = $pwd.Path

        cd ./src/FunctionApp
        Start-Process -NoNewWindow func @("start","--verbose","false")
        Start-Sleep -s 60

        cd $rootDir/test/FunctionApp.Tests
        dotnet test . -c Debug
        cd $rootDir

08-build-5.yaml

    - name: Test function app (Windows)
      if: matrix.os == 'windows-latest'
      shell: pwsh
      run: |
        dir

        $rootDir = $pwd.Path
        $func = $(Get-Command func).Source.Replace(".ps1", ".cmd")

        cd ./src/FunctionApp
        Start-Process -NoNewWindow "$func" @("start","--verbose","false")
        Start-Sleep -s 60

        cd $rootDir/test/FunctionApp.Tests
        dotnet test . -c Debug
        cd $rootDir