Beispiel #1
0
        public static Task Update()
        {
            return(Task.Factory.StartNew(() =>
            {
                lock (_lock)
                {
                    string lastModifiedFile = System.IO.Path.Combine(Root, LastModified);
                    string tmpFile = System.IO.Path.Combine(Root, Guid.NewGuid().ToString());

                    countriesRawFile = System.IO.Path.Combine(Root, countriesRawFile);
                    string allCountriesFile = System.IO.Path.Combine(Root, dataFile + ".zip");
                    string countryInfoFile = System.IO.Path.Combine(Root, "countryInfo.txt");
                    string featureCodes_enFile = System.IO.Path.Combine(Root, "featureCodes_en.txt");
                    string timeZonesFile = System.IO.Path.Combine(Root, "timeZones.txt");


                    //check to see if we have read/write persmission to disk
                    bool canReadWrite = false;
                    try
                    {
                        System.IO.File.WriteAllText(tmpFile, "testing write access");
                        string contents = System.IO.File.ReadAllText(tmpFile);
                        canReadWrite = !string.IsNullOrEmpty(contents);
                        System.IO.File.Delete(tmpFile);
                    }
                    catch (Exception)
                    {
                    }

                    //load file: GeoData-LastModified.txt
                    //if available then
                    //try to http head the data source url: http://download.geonames.org/export/dump/allCountries.zip
                    //pull off last-modified header
                    //if newer than the file last-modified, do a GET to download
                    //else
                    // do a get to download

                    bool shouldDownload = !System.IO.File.Exists(lastModifiedFile);
                    if (canReadWrite && System.IO.File.Exists(lastModifiedFile))
                    {
                        var lastModified = System.IO.File.ReadAllText(lastModifiedFile);
                        DateTime lastModifiedDate;
                        if (!DateTime.TryParse(lastModified, out lastModifiedDate))
                        {
                            shouldDownload = true;
                        }
                        else
                        {
                            var request = new WebClientRequest();
                            request.Headers = new WebHeaderCollection();
                            var client = new ParallelWebClient(request);
                            client.OpenReadTask(allCountriesUrl, "HEAD").ContinueWith(t =>
                            {
                                var headers = client.ResponseHeaders;
                                foreach (string h in headers.Keys)
                                {
                                    if (h.ToLowerInvariant() == "last-modified")
                                    {
                                        var header = headers[h];
                                        DateTime headerDate = DateTime.Now;
                                        DateTime.TryParse(header.ToString(), out headerDate);
                                        if (lastModifiedDate < headerDate)
                                        {
                                            shouldDownload = true;
                                        }
                                        break;
                                    }
                                }
                            }).Wait();
                        }
                    }

                    if (canReadWrite && shouldDownload)
                    {
                        var downloadTasks = new List <Task>();
                        var request = new WebClientRequest();
                        request.Headers = new WebHeaderCollection();
                        var client = new ParallelWebClient(request);

                        downloadTasks.Add(
                            client.DownloadData(allCountriesUrl).ContinueWith(t =>
                        {
                            if (System.IO.File.Exists(allCountriesFile))
                            {
                                System.IO.File.Delete(allCountriesFile);
                            }
                            System.IO.File.WriteAllBytes(allCountriesFile, t.Result);
                            var headers = client.ResponseHeaders;
                            foreach (string h in headers.Keys)
                            {
                                if (h.ToLowerInvariant() == "last-modified")
                                {
                                    var header = headers[h];
                                    DateTime headerDate = DateTime.Now;
                                    DateTime.TryParse(header.ToString(), out headerDate);
                                    System.IO.File.WriteAllText(lastModifiedFile, headerDate.ToString());
                                    break;
                                }
                            }
                        })
                            );

                        downloadTasks.Add(client.DownloadData(countryInfoUrl).ContinueWith(t =>
                        {
                            if (System.IO.File.Exists(countryInfoFile))
                            {
                                System.IO.File.Delete(countryInfoFile);
                            }
                            System.IO.File.WriteAllBytes(countryInfoFile, t.Result);
                        }));
                        downloadTasks.Add(client.DownloadData(featureCodes_enUrl).ContinueWith(t =>
                        {
                            if (System.IO.File.Exists(featureCodes_enFile))
                            {
                                System.IO.File.Delete(featureCodes_enFile);
                            }
                            System.IO.File.WriteAllBytes(featureCodes_enFile, t.Result);
                        }));
                        downloadTasks.Add(client.DownloadData(timeZonesUrl).ContinueWith(t =>
                        {
                            if (System.IO.File.Exists(timeZonesFile))
                            {
                                System.IO.File.Delete(timeZonesFile);
                            }
                            System.IO.File.WriteAllBytes(timeZonesFile, t.Result);
                        }));

                        Task.WaitAll(downloadTasks.ToArray());

                        //downloaded, now convert zip into serialized dat file

                        if (System.IO.File.Exists(allCountriesFile))
                        {
                            if (System.IO.File.Exists(countriesRawFile))
                            {
                                System.IO.File.Delete(countriesRawFile);
                            }
                            ICSharpCode.SharpZipLib.Zip.FastZip fz = new FastZip();
                            fz.ExtractZip(allCountriesFile, Root, FastZip.Overwrite.Always, null, null, null, true);
                            if (System.IO.File.Exists(countriesRawFile))
                            {
                                GeoData gd = GeoNameParser.ParseFile(countriesRawFile, timeZonesFile,
                                                                     featureCodes_enFile, countryInfoFile);

                                Serialize.SerializeBinaryToDisk(gd, DataFile);
                            }
                            if (System.IO.File.Exists(allCountriesFile))
                            {
                                System.IO.File.Delete(allCountriesFile);
                            }
                            if (System.IO.File.Exists(countriesRawFile))
                            {
                                System.IO.File.Delete(countriesRawFile);
                            }
                            if (System.IO.File.Exists(countryInfoFile))
                            {
                                System.IO.File.Delete(countryInfoFile);
                            }
                            if (System.IO.File.Exists(featureCodes_enFile))
                            {
                                System.IO.File.Delete(featureCodes_enFile);
                            }
                            if (System.IO.File.Exists(timeZonesFile))
                            {
                                System.IO.File.Delete(timeZonesFile);
                            }
                        }
                    }
                }
            }));
        }