/// <summary>
/// Gets a index from isolated storage of the device. Returns null, if the index isn't found
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="requestURL"></param>
/// <param name="collectionIdentifier"></param>
/// <returns>The index file or null, if the index file isn't found</returns>
public static async Task <T> getIndexAsync <T>(string requestURL, IonConfig config) where T : CacheIndex
{
try
{
// Generate filePath for index
string filePath = FilePaths.getCacheIndicesFolderPath(config) + FilePaths.getFileName(requestURL) + IonConstants.JsonFileExtension;
T cacheIndex = null;
using (await fileLocks.ObtainLock(filePath).LockAsync().ConfigureAwait(false))
{
// Create file or use existing file
StorageFile file = await _localFolder.CreateFileAsync(filePath, CreationCollisionOption.OpenIfExists);
// Read content of the file
string content = await FileIO.ReadTextAsync(file);
// Deserialize cache index
cacheIndex = JsonConvert.DeserializeObject <T>(content);
}
fileLocks.ReleaseLock(filePath);
return(cacheIndex);
}
catch (Exception e)
{
IonLogging.log("Error loading cacheIndex " + requestURL + " from isolated storage: " + e.Message, IonLogMessageTypes.ERROR);
return(null);
}
}
/// <summary>
/// Loads a collection from the isolated storage folder
/// </summary>
/// <param name="collectionIdentifier"></param>
/// <returns>The collection or null, if the collection isn't found</returns>
public static async Task <IonCollection> loadCollectionFromIsolatedStorageAsync(IonConfig config)
{
try
{
// Generate filePath for collection
string filePath = FilePaths.getCollectionFolderPath(config) + config.collectionIdentifier + IonConstants.JsonFileExtension;
IonCollection collection = null;
using (await fileLocks.ObtainLock(filePath).LockAsync().ConfigureAwait(false))
{
// Open file
StorageFile file = await _localFolder.GetFileAsync(filePath);
// Extract content
string content = await FileIO.ReadTextAsync(file);
// Deserialize collection
collection = JsonConvert.DeserializeObject <IonCollection>(content);
}
fileLocks.ReleaseLock(filePath);
return(collection);
}
catch (Exception e)
{
IonLogging.log("Error loading collection " + config.collectionIdentifier + " from isolated storeage. Message: " + e.Message, IonLogMessageTypes.ERROR);
return(null);
}
}
/// <summary>
/// Saves a index file to the isolated storage on the device
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="requestURL"></param>
/// <param name="cacheIndex"></param>
/// <param name="collectionIdentifier"></param>
/// <returns></returns>
public static async Task saveIndexAsync <T>(string requestURL, T cacheIndex, IonConfig config) where T : CacheIndex
{
try
{
// Generate filePath for index
string filePath = FilePaths.getCacheIndicesFolderPath(config) + FilePaths.getFileName(requestURL) + IonConstants.JsonFileExtension;
using (await fileLocks.ObtainLock(filePath).LockAsync().ConfigureAwait(false))
{
// Open an existing file or create a new one
StorageFile file = await _localFolder.CreateFileAsync(filePath, CreationCollisionOption.ReplaceExisting);
// Serialize cache índex
string cacheIndexSerialized = JsonConvert.SerializeObject(cacheIndex);
// Write serialzed collection to file
await FileIO.WriteTextAsync(file, cacheIndexSerialized);
}
fileLocks.ReleaseLock(filePath);
}
catch (Exception e)
{
IonLogging.log("Error saving cacheIndex to isolated storage. Message: " + e.Message, IonLogMessageTypes.ERROR);
}
}
/// <summary>
/// Saves a page to the isolated storage folder
/// </summary>
/// <param name="page"></param>
/// <returns></returns>
public static async Task savePageToIsolatedStorageAsync(IonPage page, IonConfig config)
{
try
{
// Generate filePath for page
string filePath = FilePaths.getPagesFolderPath(config) + page.identifier + IonConstants.JsonFileExtension;
using (await fileLocks.ObtainLock(filePath).LockAsync().ConfigureAwait(false))
{
// Create file or use existing file
StorageFile file = await _localFolder.CreateFileAsync(filePath, CreationCollisionOption.ReplaceExisting);
// Serialize collection
string pageSerialized = JsonConvert.SerializeObject(page);
// Write serialzed collection to file
await FileIO.WriteTextAsync(file, pageSerialized);
}
fileLocks.ReleaseLock(filePath);
}
catch (Exception e)
{
IonLogging.log("Error saving page to isolated storage: " + e.Message, IonLogMessageTypes.ERROR);
}
}
/// <summary>
/// Used to get a collection that is newer than the given date. Otherwise the content is empty
/// </summary>
/// <param name="identifier"></param>
/// <param name="lastModified"></param>
/// <returns></returns>
public async Task <HttpResponseMessage> getCollectionAsync(string identifier, DateTime lastModified)
{
try
{
// Construct request string
string requestString = _config.baseUrl + _config.locale + IonConstants.Slash + _config.collectionIdentifier + IonConstants.QueryBegin + IonConstants.QueryVariation + _config.variation;
// Add the last-modified-header
_client.DefaultRequestHeaders.Add("If-Modified-Since", lastModified.ToString("r"));
// Recieve the response
HttpResponseMessage response = await _client.GetAsync(requestString).ConfigureAwait(false);
// Remove the last-modified-header
_client.DefaultRequestHeaders.Remove("If-Modified-Since");
return(response);
}
catch (Exception e)
{
IonLogging.log("Error getting collection from server: " + e.Message, IonLogMessageTypes.ERROR);
return(null);
}
}
/// <summary>
/// Constructor with config file for initialization
/// </summary>
/// <param name="config"></param>
public DataClient(IonConfig config)
{
try
{
_config = config;
_client = new HttpClient();
_client.DefaultRequestHeaders.Authorization = _config.authenticationHeader;
}
catch (Exception e)
{
IonLogging.log("Error in configuring the data client: " + e.Message, IonLogMessageTypes.ERROR);
}
}
/// <summary>
/// Used to get a page with a given identifier
/// </summary>
/// <param name="identifier"></param>
/// <returns>Already parsed IonPage</returns>
public async Task <HttpResponseMessage> getPageAsync(string identifier)
{
try
{
string requestString = _config.baseUrl + _config.locale + IonConstants.Slash + _config.collectionIdentifier + IonConstants.Slash + identifier + IonConstants.QueryBegin + IonConstants.QueryVariation + _config.variation;
HttpResponseMessage response = await _client.GetAsync(requestString).ConfigureAwait(false);
return(response);
}
catch (Exception e)
{
IonLogging.log("Error getting page response from server! " + e.Message, IonLogMessageTypes.ERROR);
return(null);
}
}
