public ApiProviderResult DownloadFiles()
{
NasaApiProvider provider = new NasaApiProvider(nasaConfiguration);
ApiProviderResult result = provider.DownloadFiles("dates.txt");
return(result);
}
/// <summary>
/// Saves metadata file on downloaded files.
/// </summary>
/// <param name="imageData"></param>
private void SaveMetadata(ApiProviderResult imageData)
{
var metadataFolder = localFolder + "/metadata/";
if (!System.IO.Directory.Exists(metadataFolder))
{
System.IO.Directory.CreateDirectory(metadataFolder);
}
var metadataFileFullPath = metadataFolder + "metadata.json";
if (File.Exists(metadataFileFullPath))
{
File.Delete(metadataFileFullPath);
}
using (TextWriter createStream = new StreamWriter(metadataFileFullPath))
(new JsonSerializer()).Serialize(createStream, imageData);
}
/// <summary>
/// Obtain metadata for previously downloaded files.
/// </summary>
/// <returns>ApiProviderResult</returns>
public ApiProviderResult GetMetadata()
{
ApiProviderResult result;
var metadataFolder = localFolder + "/metadata/";
var metadataFileFullPath = metadataFolder + "metadata.json";
if (File.Exists(metadataFileFullPath))
{
string json = File.ReadAllText(metadataFileFullPath);
ApiProviderResult metadata = JsonConvert.DeserializeObject <ApiProviderResult>(json);
result = metadata;
}
else
{
result = new ApiProviderResult()
{
success = false, message = "Metadata file not found. Please call Download endpoint before attempting to get metadata."
};
}
return(result);
}
// TODO: add action filter for handling exceptions.
public async Task <IActionResult> ViewFilesAsync()
{
var res = await RestHelper.ProcessGetRequestAsync("/api/image/getmetadata");
var data = res.data;
var metadata = JsonConvert.DeserializeObject <ApiProviderResult>(data);
if (metadata == null || metadata.data == null)
{
metadata = new ApiProviderResult()
{
data = new List <ImageData>()
};
ViewData["Message"] = "No images. Please use Download link above to get images before viewing.";
}
else
{
ViewData["Message"] = $"Images available for viewing: {metadata.data.Count}.";
}
ViewData["Images"] = metadata.data;
return(View());
}
/// <summary>
/// Method drives download process by:
/// 1. Reading input file from dates.txt
/// 2. Getting metadata for a rover/date combinations.
/// 3. Write files to disk.
/// 4. Saves metadata file with information on downloaded files.
/// 5. Sends back report on downloaded/existing image files.
/// </summary>
/// <param name="inputFile"></param>
/// <returns></returns>
public ApiProviderResult DownloadFiles(string inputFile)
{
ApiProviderResult result;
// Read in the dates from input file
var dateFileContents = DateHelper.GetDatesFromFileAsString(inputFile);
var dates = DateHelper.GetFormattedDatesFromString(dateFileContents);
if (dates.Count > 0)
{
result = new ApiProviderResult();
result.data = new List <ImageData>();
List <Task> tasks = new List <Task>();
// Process all the dates from input file and keep track of processing for each date
foreach (var date in dates)
{
// TODO: need to figure out what to do with invalid dates.
if (date.Ticks > 0)
{
tasks.Add(Task.Run(() => DownloadFilesForDate(date.ToString("yyyy-MM-dd"))));
}
}
Task.WaitAll(tasks.ToArray());
foreach (Task <Dictionary <string, List <RoverPhotosResponse> > > task in tasks)
{
var taskResult = task.Result;
var imageData = new ImageData();
foreach (var roverImageData in taskResult)
{
var date = roverImageData.Key;
foreach (var roverImage in roverImageData.Value)
{
roverImage.photos.ForEach(delegate(RoverPhotosResponse.Photo photo)
{
var imageData = new ImageData()
{
imageSource = photo.img_src,
filename = Path.GetFileName(photo.img_src),
localPath = $"{localFolder}{date}/{photo.rover.name}/{Path.GetFileName(photo.img_src)}",
roverName = photo.rover.name,
date = date,
isDownloaded = photo.isDownloaded,
isExists = photo.isExists
};
result.data.Add(imageData);
});
}
}
}
// Save metadata for more performant viewing process later.
SaveMetadata(result);
result.success = true;
result.message = $"Images found on NASA site: {result.data.Count}. Number of images downloaded: {result.data.Where(w => w.isDownloaded).Count()}. ";
result.message += $"Number of images previously downloaded: {result.data.Where(w => w.isExists).Count()}.";
}
else
{
result = new ApiProviderResult()
{
message = "Unable to read dates for input."
};
}
return(result);
}
