private static async Task UpdateSamePersonUsingOptimisticLockingWithCasValue(ICouchbaseCollection collection, string documentId)
{
var getResult = await collection.GetAsync(documentId);
var person = getResult.ContentAs <Person>();
var newPerson1 = person.WithSomeNumber(1);
var replaceOptions = new ReplaceOptions().Cas(getResult.Cas);
// csak akkor replace-el, ha a doksi CAS-ja egyezik a ReplaceOptions-ben megadottal
// az UpsertAsync()-nek beadható UpsertOption()-nek nincs Cas() művelete, ezért használom Replace()-t
var mutationResult1 = await collection.ReplaceAsync(documentId, newPerson1, replaceOptions);
try
{
var newPerson2 = person.WithSomeNumber(2);
// a doksi CAS-ja nem egyezik a korábban lekérttel, ezért dob
var mutationResult2 = await collection.ReplaceAsync(documentId, newPerson2, replaceOptions);
}
catch (Couchbase.Core.Exceptions.KeyValue.DocumentExistsException ex)
{
// a hiba részeleteit tartalmazza; típusa: Couchbase.Core.Exceptions.KeyValue.KeyValueErrorContext: több minden van benne, mint IErrorContext-en
var replaceContext = ex.Context;
}
}
public static Task <IMutationResult> ReplaceAsync <T>(this ICouchbaseCollection collection, string id, T content,
Action <ReplaceOptions> configureOptions)
{
var options = new ReplaceOptions();
configureOptions(options);
return(collection.ReplaceAsync(id, content, options));
}
/// <inheritdoc/>
public async Task Renew(TimeSpan expiration, CancellationToken cancellationToken = default)
{
if (expiration <= TimeSpan.Zero)
{
throw new ArgumentOutOfRangeException(nameof(expiration), "Value must be positive.");
}
var key = LockDocument.GetKey(Name);
var document = new LockDocument
{
Holder = Holder,
RequestedDateTime = DateTime.UtcNow
};
bool lockAcquired = false;
IMutationResult?result = null;
try
{
if (_cas == 0)
{
// We're creating a new lock
_logger.LogDebug("Requesting lock '{name}' for holder '{holder}' for {expiration}", Name, Holder,
expiration);
result = await _collection.InsertAsync(key, document,
new InsertOptions().Expiry(expiration).CancellationToken(cancellationToken))
.ConfigureAwait(false);
}
else
{
_logger.LogDebug("Renewing lock '{name}' for holder '{holder}' for {expiration}", Name, Holder,
expiration);
result = await _collection.ReplaceAsync(key, document,
new ReplaceOptions().Expiry(expiration).CancellationToken(cancellationToken).Cas(_cas))
.ConfigureAwait(false);
}
lockAcquired = true;
}
catch (CasMismatchException)
{
// This is a valid case, trap the exception
_logger.LogDebug("CAS mismatch updating lock '{name}'", Name);
}
catch (DocumentExistsException)
{
// This is a valid case, trap the exception
_logger.LogDebug("Lock document already exists for lock '{name}'", Name);
}
catch (DocumentNotFoundException)
{
// This is a valid, but rare, case where the document being renewed expired before
// the renewal. In this case, we'll let the logic move on, which will recreate the document.
_logger.LogDebug("Lock document missing for lock '{name}'", Name);
}
if (lockAcquired)
{
_logger.LogDebug("Lock '{name}' issued to holder '{holder}'", Name, Holder);
_expirationInterval = expiration;
_cas = result !.Cas;
return;
}
if (!lockAcquired)
{
_logger.LogDebug("Lock '{name}' unavailable, getting lock info", Name);
IGetResult getResult;
try
{
getResult = await _collection.GetAsync(key).ConfigureAwait(false);
}
catch (DocumentNotFoundException)
{
try
{
// Couldn't find the lock, must have expired between Insert and Get, try one more time
result = await _collection.InsertAsync(key, document,
new InsertOptions().Expiry(expiration).CancellationToken(cancellationToken))
.ConfigureAwait(false);
}
catch (DocumentExistsException)
{
throw new CouchbaseLockUnavailableException(Name);
}
_logger.LogDebug("Lock '{name}' issued to holder '{holder}'", Name, Holder);
_expirationInterval = expiration;
_cas = result.Cas;
return;
}
_logger.LogDebug("Unable to acquire lock '{name}' for holder '{holder}'", Name, Holder);
throw new CouchbaseLockUnavailableException(Name)
{
Holder = getResult.ContentAs <LockDocument>().Holder
};
}
}
public static Task <IMutationResult> ReplaceAsync <T>(this ICouchbaseCollection collection, string id, T content)
{
return(collection.ReplaceAsync(id, content, ReplaceOptions.Default));
}
/// <summary>
/// Executes a query and ingests the results as documents into Couchbase server for further analytics.
/// <para>
/// NOTE: This is an experimental API and may change in the future.
/// </para>
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="cluster"></param>
/// <param name="collection"></param>
/// <param name="statement"></param>
/// <param name="ingestOptions"></param>
/// <returns></returns>
public static async Task <IEnumerable <IMutationResult> > IngestAsync <T>(this ICluster cluster, string statement, ICouchbaseCollection collection, IngestOptions ingestOptions = null)
{
//use defaults if not options not explicitly passed
ingestOptions ??= new IngestOptions();
if (ingestOptions.TokenValue.IsCancellationRequested)
{
ingestOptions.TokenValue.ThrowIfCancellationRequested();
}
//execute the analytics query
var result = await cluster.AnalyticsQueryAsync <T>(
statement,
options => options.CancellationToken(ingestOptions.TokenValue)
).ConfigureAwait(false);
// ingest result into collection
var results = new ConcurrentBag <Task <IMutationResult> >();
await foreach (var row in result.WithCancellation(ingestOptions.TokenValue).ConfigureAwait(false))
{
Task <IMutationResult> op;
switch (ingestOptions.IngestMethodValue)
{
case IngestMethod.Insert:
op = collection.InsertAsync(
ingestOptions.IdGeneratorValue(row),
row,
options =>
{
options.Expiry(ingestOptions.ExpiryValue);
options.Timeout(ingestOptions.TimeoutValue);
});
break;
case IngestMethod.Upsert:
op = collection.UpsertAsync(
ingestOptions.IdGeneratorValue(row),
row,
options =>
{
options.Expiry(ingestOptions.ExpiryValue);
options.Timeout(ingestOptions.TimeoutValue);
});
break;
case IngestMethod.Replace:
op = collection.ReplaceAsync(
ingestOptions.IdGeneratorValue(row),
row,
options =>
{
options.Expiry(ingestOptions.ExpiryValue);
options.Timeout(ingestOptions.TimeoutValue);
});
break;
default:
throw new ArgumentOutOfRangeException();
}
results.Add(op);
}
return(await Task.WhenAll(results).ConfigureAwait(false));
}
