/// <summary>
/// Gets a file stream from the CAS either directly or by materlializing a file in the temp path and then opening it for read.
/// </summary>
/// <param name="hash">Hash for CAS entry</param>
/// <param name="method">Method used to access CAS</param>
/// <param name="session">Cache session</param>
/// <returns>A stream pointing to the file contents, or a failure.</returns>
private static async Task <Possible <StreamWithLength, Failure> > GetStreamAsync(CasHash hash, CasAccessMethod method, ICacheReadOnlySession session)
{
switch (method)
{
case CasAccessMethod.Stream:
return(await session.GetStreamAsync(hash));
case CasAccessMethod.FileSystem:
string filePath = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
string placedFilePath = await session.ProduceFileAsync(hash, filePath, FileState.ReadOnly).SuccessAsync();
XAssert.AreEqual(filePath, placedFilePath);
FileStream fs = new FileStream(placedFilePath, FileMode.Open, FileAccess.Read, FileShare.Delete | FileShare.Read);
File.Delete(placedFilePath);
return(fs.WithLength());
default:
throw new NotImplementedException();
}
}
public Task <Possible <string, Failure> > ProduceFileAsync(
CasHash hash,
string filename,
FileState fileState,
UrgencyHint urgencyHint,
Guid activityId)
{
var callback = ProduceFileAsyncCallback;
if (callback != null)
{
return(callback(
hash,
filename,
fileState,
urgencyHint,
activityId,
m_realSession));
}
else
{
return(m_realSession.ProduceFileAsync(
hash,
filename,
fileState,
urgencyHint,
activityId));
}
}
public async Task <Possible <string, Failure> > ProduceFileAsync(CasHash hash, string filename, FileState fileState, UrgencyHint urgencyHint, Guid activityId)
{
using (var eventing = new ProduceFileActivity(CompositingCache.EventSource, activityId, this))
{
eventing.Start(hash, filename, fileState, urgencyHint);
return(eventing.Returns(await m_casSession.ProduceFileAsync(hash, filename, fileState, urgencyHint, activityId)));
}
}
// We don't pin here as we do this after having pinned everything in the PinAndGetStreamSize
private async Task <long> GetAsFile(ICacheReadOnlySession session, CasHash hash)
{
long result;
var tmpFile = FileUtilities.GetTempFileName();
try
{
await session.ProduceFileAsync(hash, tmpFile, FileState.ReadOnly).SuccessAsync();
result = new FileInfo(tmpFile).Length;
}
finally
{
File.Delete(tmpFile);
}
return(result);
}
public Task <Possible <string, Failure> > ProduceFileAsync(CasHash hash, string filename, FileState fileState, UrgencyHint urgencyHint, Guid activityId)
{
return(m_session.ProduceFileAsync(hash, filename, fileState, urgencyHint, activityId));
}