/// <summary>
/// Update a document in DynamoDB, with a hash-and-range primary key to identify
/// the document, and using the specified config.
/// </summary>
/// <param name="doc">Attributes to update.</param>
/// <param name="hashKey">Hash key element of the document.</param>
/// <param name="rangeKey">Range key element of the document.</param>
/// <param name="config">Configuration to use.</param>
/// <returns>Null or updated attributes, depending on config.</returns>
/// <seealso cref="Amazon.DynamoDB.DocumentModel.UpdateItemOperationConfig"/>
public Document UpdateItem(Document doc, Primitive hashKey, Primitive rangeKey, UpdateItemOperationConfig config)
{
return UpdateHelper(doc, MakeKey(hashKey, rangeKey), config, false);
}
internal Document UpdateHelper(Document doc, Key key, UpdateItemOperationConfig config, bool isAsync)
{
var currentConfig = config ?? new UpdateItemOperationConfig();
// If the keys have been changed, treat entire document as having changed
bool haveKeysChanged = HaveKeysChanged(doc);
bool updateChangedAttributesOnly = !haveKeysChanged;
var attributeUpdates = doc.ToAttributeUpdateMap(updateChangedAttributesOnly);
foreach (var keyName in this.keyNames)
{
attributeUpdates.Remove(keyName);
}
UpdateItemRequest req = new UpdateItemRequest
{
TableName = TableName,
Key = key,
AttributeUpdates = attributeUpdates.Count == 0 ?
new Dictionary<string,AttributeValueUpdate>() : attributeUpdates,
ReturnValues = EnumToStringMapper.Convert(currentConfig.ReturnValues)
};
req.BeforeRequestEvent += isAsync ?
new RequestEventHandler(UserAgentRequestEventHandlerAsync) :
new RequestEventHandler(UserAgentRequestEventHandlerSync);
if (currentConfig.Expected != null)
req.Expected = currentConfig.Expected.ToExpectedAttributeMap();
var resp = DDBClient.UpdateItem(req);
var returnedAttributes = resp.UpdateItemResult.Attributes;
doc.CommitChanges();
Document ret = null;
if (currentConfig.ReturnValues != ReturnValues.None)
{
ret = Document.FromAttributeMap(returnedAttributes);
}
return ret;
}
/// <summary>
/// Initiates the asynchronous execution of the UpdateItem operation.
/// <seealso cref="Amazon.DynamoDB.DocumentModel.Table.UpdateItem"/>
/// </summary>
/// <param name="doc">Attributes to update.</param>
/// <param name="hashKey">Hash key element of the document.</param>
/// <param name="rangeKey">Range key element of the document.</param>
/// <param name="config">Configuration to use.</param>
/// <param name="callback">An AsyncCallback delegate that is invoked when the operation completes.</param>
/// <param name="state">A user-defined state object that is passed to the callback procedure. Retrieve this object from within the callback
/// procedure using the AsyncState property.</param>
/// <returns>An IAsyncResult that can be used to poll or wait for results, or both; this value is also needed when invoking EndUpdateItem
/// operation.</returns>
public IAsyncResult BeginUpdateItem(Document doc, Primitive hashKey, Primitive rangeKey, UpdateItemOperationConfig config, AsyncCallback callback, object state)
{
return DynamoDBAsyncExecutor.BeginOperation(() => UpdateHelper(doc, MakeKey(hashKey, rangeKey), config, true), callback, state);
}
/// <summary>
/// Update a document in DynamoDB, using specified config.
/// </summary>
/// <param name="doc">Document to update.</param>
/// <param name="config">Configuration to use.</param>
/// <returns>Null or updated attributes, depending on config.</returns>
/// <seealso cref="Amazon.DynamoDB.DocumentModel.UpdateItemOperationConfig"/>
public Document UpdateItem(Document doc, UpdateItemOperationConfig config)
{
return UpdateHelper(doc, MakeKey(doc), config, false);
}
private Document UpdateHelper(Document doc, Key key, UpdateItemOperationConfig config)
{
var currentConfig = config ?? new UpdateItemOperationConfig();
var attributeUpdates = doc.ToAttributeUpdateMap(true);
foreach (var keyName in this.keyNames)
{
if (keyName != null)
{
attributeUpdates.Remove(keyName);
}
}
UpdateItemRequest req = new UpdateItemRequest
{
TableName = TableName,
Key = key,
AttributeUpdates = attributeUpdates,
ReturnValues = EnumToStringMapper.Convert(currentConfig.ReturnValues)
};
req.BeforeRequestEvent += new RequestEventHandler(this.UserAgentRequestEventHandler);
if (currentConfig.Expected != null)
req.Expected = currentConfig.Expected.ToExpectedAttributeMap();
var resp = DDBClient.UpdateItem(req);
doc.CommitChanges();
Document ret = null;
if (currentConfig.ReturnValues != ReturnValues.None)
{
ret = Document.FromAttributeMap(resp.UpdateItemResult.Attributes);
}
return ret;
}
/// <summary>
/// Update a document in DynamoDB, with a hash primary key to identify the
/// document, and using the specified config.
/// </summary>
/// <param name="doc">Attributes to update.</param>
/// <param name="hashKey">Hash key element of the document.</param>
/// <param name="config">Configuration to use.</param>
/// <returns>Null or updated attributes, depending on config.</returns>
/// <seealso cref="Amazon.DynamoDB.DocumentModel.UpdateItemOperationConfig"/>
public Document UpdateItem(Document doc, Primitive hashKey, UpdateItemOperationConfig config)
{
return UpdateHelper(doc, MakeKey(hashKey, null), config);
}
internal Document UpdateHelper(Document doc, Key key, UpdateItemOperationConfig config, bool isAsync)
{
var currentConfig = config ?? new UpdateItemOperationConfig();
var attributeUpdates = doc.ToAttributeUpdateMap(true);
foreach (var keyName in this.keyNames)
{
attributeUpdates.Remove(keyName);
}
ReturnValues currentReturnValue = currentConfig.ReturnValues;
bool keysOnlyUpdate = attributeUpdates.Count == 0;
// If there are no non-key attributes, make an Update call with AllNewAttributes
// return value. If no attributes returned, the item doesn't exist yet, so
// make a Put call.
if (keysOnlyUpdate)
{
currentReturnValue = ReturnValues.AllNewAttributes;
}
UpdateItemRequest req = new UpdateItemRequest
{
TableName = TableName,
Key = key,
AttributeUpdates = attributeUpdates,
ReturnValues = EnumToStringMapper.Convert(currentReturnValue)
};
req.BeforeRequestEvent += isAsync ?
new RequestEventHandler(UserAgentRequestEventHandlerAsync) :
new RequestEventHandler(UserAgentRequestEventHandlerSync);
if (currentConfig.Expected != null)
req.Expected = currentConfig.Expected.ToExpectedAttributeMap();
var resp = DDBClient.UpdateItem(req);
var returnedAttributes = resp.UpdateItemResult.Attributes;
doc.CommitChanges();
if (keysOnlyUpdate)
{
if (returnedAttributes == null || returnedAttributes.Count == 0)
{
// if only keys were specified and no attributes are returned, we must issue a Put
return CallKeysOnlyPut(key, currentConfig, isAsync);
}
else
{
// update was called with AllNewAttributes, item exists
// return correct set of attributes
// [None] is handled at the end
// [AllNewAttributes, AllOldAttributes] are equivalent in this case, no-op
// [UpdatedNewAttributes, UpdatedOldAttributes] must return no attributes
switch (currentConfig.ReturnValues)
{
case ReturnValues.UpdatedNewAttributes:
case ReturnValues.UpdatedOldAttributes:
returnedAttributes = new Dictionary<string,AttributeValue>();
break;
}
}
}
Document ret = null;
if (currentConfig.ReturnValues != ReturnValues.None)
{
ret = Document.FromAttributeMap(returnedAttributes);
}
return ret;
}
// Creates a PutItemOperationConfig for the keys-only Put operation
private PutItemOperationConfig CreateKeysOnlyPutConfig(Key key, UpdateItemOperationConfig config)
{
// configure the expected document
Document expected = new Document();
expected[this.HashKeyName] = null;
if (this.RangeKeyIsDefined)
{
expected[this.RangeKeyName] = null;
}
// create the PutItemOperationConfig
var putConfig = new PutItemOperationConfig
{
Expected = expected,
ReturnValues = ReturnValues.None
};
return putConfig;
}
// calls Put, but returns like Update
private Document CallKeysOnlyPut(Key key, UpdateItemOperationConfig config, bool isAsync)
{
// configure the keys-only Document
Document doc = CreateKeysOnlyDocument(key);
// configure the put operation
PutItemOperationConfig putConfig = CreateKeysOnlyPutConfig(key, config);
// call put
PutItemHelper(doc, putConfig, isAsync);
/*
New item created, return Update-appropriate response.
For update, when no item exists:
[None] - returns null,
[AllOld, UpdatedNew, UpdatedOld] - return no attributes
[AllNew] - returns all attributes
*/
Document response;
switch (config.ReturnValues)
{
case ReturnValues.None:
response = null;
break;
case ReturnValues.AllNewAttributes:
response = doc;
break;
default:
response = new Document();
break;
}
return response;
}