How to debug AnalyticsReporting V4?

Question

I'm trying to debug this code, to find out where is it erroring, but can't do it.

I'm not sure if viewId should just be an int or ga:<viewId>, I tried both ways and still getting null data.

List<Report>.Data always returns null.

Code:

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Web;
using Google.Apis.Analytics.v3;
using Google.Apis.Analytics.v3.Data;
using Google.Apis.Services;
using Google.Apis.AnalyticsReporting.v4;
using Google.Apis.AnalyticsReporting.v4.Data;
using Google.Apis.Auth.OAuth2;
using Google.Apis.Util;
using Google.Apis.Logging;

public class GoogleAnalyticsApi
{
    private const string keyPath = @"<JsonFileAbsolutePath>";
    private string accountEmailAddress = "googleaccount@mail";
    private string keyPassword = "<secret>";
    private string viewId;
    public AnalyticsService Service { get; set; }
    private AnalyticsReportingService gaService;

    public GoogleAnalyticsApi(string viewId)
    {
        try
        {
            var logger = new ConsoleLogger(LogLevel.Error);
            GoogleCredential credentials;
            using (var stream = new FileStream(keyPath, FileMode.Open, FileAccess.Read))
            {

                string[] scopes = {AnalyticsReportingService.Scope.AnalyticsReadonly};
                var googleCredential = GoogleCredential.FromStream(stream);
                credentials = googleCredential.CreateScoped(scopes).ThrowIfNull("");

            }

            this.gaService = new AnalyticsReportingService(
                new BaseClientService.Initializer
                {
                    ApplicationName = "Testing",
                    HttpClientInitializer = credentials
                });
        }
        catch (Exception e)
        {
            throw new Exception("Can't start Google service.");
        }

        this.viewId = viewId;
    }

    public IList<Report> GetReports(DateRange dateRange, List<Metric> metrics, List<Dimension> dimensions, string filters = null, List<OrderBy> orderBys = null)
    {
        var reportRequest = new ReportRequest
        {
            DateRanges = new List<DateRange> { dateRange },
            Dimensions = dimensions,
            Metrics = metrics,
            FiltersExpression = filters,
            ViewId = this.viewId,
            OrderBys = orderBys
        };

        var getReportsRequest = new GetReportsRequest
        {

            ReportRequests = new List<ReportRequest> { reportRequest }
        };
        ReportsResource.BatchGetRequest batchRequest = this.gaService.Reports.BatchGet(getReportsRequest);
        GetReportsResponse resp = batchRequest.Execute();
        return resp.Reports;
    }

    public IList<Profile> GetAvailableProfiles()
    {
        var response = Service.Management.Profiles.List("~all", "~all").Execute();
        return response.Items;
    }
}

The category I'm trying to filter exists, and if I try to use these exact metrics, dimensions, and filters at: https://ga-dev-tools.appspot.com/query-explorer/#report-end it all works just fine.

And I'm calling it from this Controller:

    private void Test(HttpContext ctx)
    {
        var dateRange = new DateRange
        {
            StartDate = "2018-01-01",
            EndDate = "2018-02-01"
        };
        List<Metric> metrics = GenerateMetricsListFromStrings(new ArrayList()
        {
            "ga:pageviews",
            "ga:totalEvents",
            "ga:pageviewsPerSession",
            "ga:users",
            "ga:sessions"
        });
        List<Dimension> dimensions = GenerateDimensionsListFromStrings(new ArrayList()
        {
            "ga:browser",
            "ga:operatingSystem",
            "ga:country",
            "ga:hour",
            "ga:date"
        });
        string filters = "ga:eventCategory==Test";
        IList<Report> data = this.ga.GetReports(dateRange, metrics, dimensions, filters);
        foreach (var item in data.First().Data.Rows)
        {
            ctx.Response.Write(
                String.Join(", ", item.Dimensions) + " " + String.Join(", ", item.Metrics.First().Values)
            );
        }
    }

    /**
     * ...
     */
    private List<Metric> GenerateMetricsListFromStrings(ArrayList metrics)
    {
        List<Metric> metrictsList = new List<Metric>();
        foreach (string metric in metrics)
        {
            metrictsList.Add(new Metric()
            {
                Expression = metric
            });
        }

        return metrictsList;
    }

    /**
     * ...
     */
    private List<Dimension> GenerateDimensionsListFromStrings(ArrayList dimensions)
    {
        List<Dimension> dimensionsList = new List<Dimension>();
        foreach (string dim in dimensions)
        {
            dimensionsList.Add(new Dimension()
            {
                Name =  dim
            });
        }

        return dimensionsList;
    }

Thanks.

Answer 1

Good grief, I had wrong the date...

I was trying to get data from 2018 instead of this year...

        var dateRange = new DateRange
        {
            StartDate = "2018-01-01",
            EndDate = "2019-02-01"
        };