/// <summary>
/// Creates a plugin from the discovered plugin.
/// We firstly check the cache for the operation claims for the given request key.
/// If there is a valid cache entry, and it does contain the requested operation claim, then we start the plugin, and if need be update the cache value itself.
/// If there is a valid cache entry, and it does NOT contain the requested operation claim, then we return a null.
/// If there is no valid cache entry or an invalid one, we start the plugin as normally, return an active plugin even if the requested claim is not available, and write a cache entry.
/// </summary>
/// <param name="result">plugin discovery result</param>
/// <param name="requestedOperationClaim">The requested operation claim</param>
/// <param name="requestKey">plugin request key</param>
/// <param name="packageSourceRepository">package source repository</param>
/// <param name="serviceIndex">service index</param>
/// <param name="cancellationToken">cancellation token</param>
/// <returns>A plugin creation result, null if the requested plugin cannot handle the given operation claim</returns>
private async Task <Tuple <bool, PluginCreationResult> > TryCreatePluginAsync(
PluginDiscoveryResult result,
OperationClaim requestedOperationClaim,
PluginRequestKey requestKey,
string packageSourceRepository,
JObject serviceIndex,
CancellationToken cancellationToken)
{
PluginCreationResult pluginCreationResult = null;
var cacheEntry = new PluginCacheEntry(_pluginsCacheDirectory.Value, result.PluginFile.Path, requestKey.PackageSourceRepository);
return(await ConcurrencyUtilities.ExecuteWithFileLockedAsync(
cacheEntry.CacheFileName,
action : async lockedToken =>
{
if (cacheEntry.OperationClaims == null || cacheEntry.OperationClaims.Contains(requestedOperationClaim))
{
if (result.PluginFile.State.Value == PluginFileState.Valid)
{
var plugin = await _pluginFactory.GetOrCreateAsync(
result.PluginFile.Path,
PluginConstants.PluginArguments,
new RequestHandlers(),
_connectionOptions,
cancellationToken);
var utilities = await PerformOneTimePluginInitializationAsync(plugin, cancellationToken);
// We still make the GetOperationClaims call even if we have the operation claims cached. This is a way to self-update the cache.
var operationClaims = await _pluginOperationClaims.GetOrAdd(
requestKey,
key => new Lazy <Task <IReadOnlyList <OperationClaim> > >(() =>
GetPluginOperationClaimsAsync(
plugin,
packageSourceRepository,
serviceIndex,
cancellationToken))).Value;
if (!EqualityUtility.SequenceEqualWithNullCheck(operationClaims, cacheEntry.OperationClaims))
{
cacheEntry.OperationClaims = operationClaims;
await cacheEntry.UpdateCacheFileAsync();
}
pluginCreationResult = new PluginCreationResult(
plugin,
utilities.Value,
operationClaims);
}
else
{
pluginCreationResult = new PluginCreationResult(result.Message);
}
}
return new Tuple <bool, PluginCreationResult>(pluginCreationResult != null, pluginCreationResult);
},
token : cancellationToken
));
}
private async Task <PluginCreationResult> CreatePluginAsync(PluginDiscoveryResult result, PluginRequestKey requestKey, string packageSourceRepository, JObject serviceIndex, CancellationToken cancellationToken)
{
PluginCreationResult pluginCreationResult = null;
if (result.PluginFile.State.Value == PluginFileState.Valid)
{
var plugin = await _pluginFactory.GetOrCreateAsync(
result.PluginFile.Path,
PluginConstants.PluginArguments,
new RequestHandlers(),
_connectionOptions,
cancellationToken);
var utilities = await PerformOneTimePluginInitializationAsync(plugin, cancellationToken);
var lazyOperationClaims = _pluginOperationClaims.GetOrAdd(
requestKey,
key => new Lazy <Task <IReadOnlyList <OperationClaim> > >(() =>
GetPluginOperationClaimsAsync(
plugin,
packageSourceRepository,
serviceIndex,
cancellationToken)));
await lazyOperationClaims.Value;
pluginCreationResult = new PluginCreationResult(
plugin,
utilities.Value,
lazyOperationClaims.Value.Result);
}
else
{
pluginCreationResult = new PluginCreationResult(result.Message);
}
return(pluginCreationResult);
}
/// <summary>
/// Creates a plugin from the discovered plugin.
/// We firstly check the cache for the operation claims for the given request key.
/// If there is a valid cache entry, and it does contain the requested operation claim, then we start the plugin, and if need be update the cache value itself.
/// If there is a valid cache entry, and it does NOT contain the requested operation claim, then we return a null.
/// If there is no valid cache entry or an invalid one, we start the plugin as normally, return an active plugin even if the requested claim is not available, and write a cache entry.
/// </summary>
/// <param name="result">plugin discovery result</param>
/// <param name="requestedOperationClaim">The requested operation claim</param>
/// <param name="requestKey">plugin request key</param>
/// <param name="packageSourceRepository">package source repository</param>
/// <param name="serviceIndex">service index</param>
/// <param name="cancellationToken">cancellation token</param>
/// <returns>A plugin creation result, null if the requested plugin cannot handle the given operation claim</returns>
private async Task <Tuple <bool, PluginCreationResult> > TryCreatePluginAsync(
PluginDiscoveryResult result,
OperationClaim requestedOperationClaim,
PluginRequestKey requestKey,
string packageSourceRepository,
JObject serviceIndex,
CancellationToken cancellationToken)
{
// This is a non cancellable task.
// We should only honor cancellation requests we can recover from.
// Once we have reached this part of the code, we do the plugin initialization
// handshake, operation claims, and shut down set up.
// If either one of these tasks fails then the plugin itself is not usable for the rest of the process.
// We could consider handling each of this operations more cleverly,
// but simplicity and readability is prioritized
cancellationToken = CancellationToken.None;
PluginCreationResult pluginCreationResult = null;
var cacheEntry = new PluginCacheEntry(_pluginsCacheDirectoryPath.Value, result.PluginFile.Path, requestKey.PackageSourceRepository);
ConcurrencyUtilities.ExecuteWithFileLocked(cacheEntry.CacheFileName, cacheEntry.LoadFromFile);
if (cacheEntry.OperationClaims == null || cacheEntry.OperationClaims.Contains(requestedOperationClaim))
{
try
{
if (result.PluginFile.State.Value == PluginFileState.Valid)
{
var plugin = await _pluginFactory.GetOrCreateAsync(
result.PluginFile.Path,
PluginConstants.PluginArguments,
new RequestHandlers(),
_connectionOptions,
cancellationToken);
var utilities = await PerformOneTimePluginInitializationAsync(plugin, cancellationToken);
// We still make the GetOperationClaims call even if we have the operation claims cached. This is a way to self-update the cache.
var operationClaims = await _pluginOperationClaims.GetOrAdd(
requestKey,
key => new Lazy <Task <IReadOnlyList <OperationClaim> > >(() =>
GetPluginOperationClaimsAsync(
plugin,
packageSourceRepository,
serviceIndex,
cancellationToken))).Value;
if (!EqualityUtility.SequenceEqualWithNullCheck(operationClaims, cacheEntry.OperationClaims))
{
cacheEntry.OperationClaims = operationClaims;
await utilities.Value.DoOncePerPluginLifetimeAsync(
nameof(PluginCacheEntry),
() => ConcurrencyUtilities.ExecuteWithFileLockedAsync(
cacheEntry.CacheFileName,
action: async lockedToken =>
{
await cacheEntry.UpdateCacheFileAsync();
return(Task.FromResult <object>(null));
},
token: cancellationToken),
cancellationToken);
}
pluginCreationResult = new PluginCreationResult(
plugin,
utilities.Value,
operationClaims);
}
else
{
pluginCreationResult = new PluginCreationResult(result.Message);
}
}
catch (Exception e)
{
pluginCreationResult = new PluginCreationResult(
string.Format(CultureInfo.CurrentCulture,
Strings.Plugin_ProblemStartingPlugin,
result.PluginFile.Path,
e.Message),
e);
}
}
return(new Tuple <bool, PluginCreationResult>(pluginCreationResult != null, pluginCreationResult));
}
