public async Task <List <T> > FromQueryAsync(QueryOperationConfig queryOperationConfig, string overrideTableName = null)
{
using (var dbcontext = new DynamoDBContext(client))
{
if (!string.IsNullOrEmpty(overrideTableName))
{
return(await dbcontext.FromQueryAsync <T>(queryOperationConfig, new DynamoDBOperationConfig { OverrideTableName = overrideTableName }).GetNextSetAsync());
}
else
{
return(await dbcontext.FromQueryAsync <T>(queryOperationConfig).GetNextSetAsync());
}
}
}
public IEnumerable <LeaderBoardEntry> GetLeaderBoard(string match, int duration)
{
DynamoDBContext context = new DynamoDBContext(_client);
QueryFilter filter = new QueryFilter();
filter.AddCondition("Match", QueryOperator.Equal, match);
filter.AddCondition("TimeStamp", QueryOperator.GreaterThanOrEqual, DateTime.Now.AddHours(-duration));
QueryOperationConfig queryOperationConfig = new QueryOperationConfig {
Filter = filter, IndexName = "LeaderBoardIndex"
};
var playerStats = context.FromQueryAsync <PlayerStat>(queryOperationConfig).GetNextSetAsync().GetAwaiter().GetResult();
playerStats.Sort((x, y) => { return(y.Score.CompareTo(x.Score)); });
List <LeaderBoardEntry> leaderBoardEntries = new List <LeaderBoardEntry>();
foreach (var playerStat in playerStats)
{
if (leaderBoardEntries.Find(item => item.UserName == playerStat.UserName) == null)
{
leaderBoardEntries.Add(new LeaderBoardEntry
{
Kills = playerStat.Kills,
Score = playerStat.Score,
UserName = playerStat.UserName,
Rank = leaderBoardEntries.FindAll(item => item.Score > playerStat.Score).Count + 1
});
}
}
return(leaderBoardEntries);
}
public static Task <List <T> > QueryItemAsync <T>(string columnName, QueryOperator queryOperator, string queryValue)
{
string indexName = null;
foreach (var property in typeof(T).GetProperties())
{
if (property.CustomAttributes.Any(attribute =>
attribute.AttributeType == typeof(DynamoDBHashKeyAttribute)))
{
indexName = property.Name;
}
if (!string.IsNullOrEmpty(indexName))
{
break;
}
}
Console.WriteLine();
var search = Context.FromQueryAsync <T>(new QueryOperationConfig
{
IndexName = indexName,
Filter = new QueryFilter(columnName, queryOperator, queryValue)
});
return(search.GetRemainingAsync());
}
public async Task <List <Channel> > GetBotsByChannelId(string id)
{
var query = _context.QueryAsync <Channel>(id);
var botQuery = new Amazon.DynamoDBv2.DocumentModel.QueryOperationConfig
{
IndexName = "BotId-ChannelId-index"
};
botQuery.KeyExpression = new Amazon.DynamoDBv2.DocumentModel.Expression
{
ExpressionStatement = "BotId = :botId",
ExpressionAttributeValues = new Dictionary <string, Amazon.DynamoDBv2.DocumentModel.DynamoDBEntry>
{
{ ":botId", id }
}
};
var botresult = _context.FromQueryAsync <Channel>(botQuery);
var data = await botresult.GetRemainingAsync();
var data2 = await query.GetRemainingAsync();
return(data.Union(data2).ToList());
}
public async Task QueryByConditions()
{
Console.WriteLine("Query where name starts with 'M' for ID country sorted descending: ");
QueryFilter filter = new QueryFilter();
filter.AddCondition(nameof(Profile.CountryId), QueryOperator.Equal, "ID");
filter.AddCondition(nameof(Profile.Name), QueryOperator.BeginsWith, "M");
List <Profile> profiles = await _context.FromQueryAsync <Profile>(new QueryOperationConfig
{
BackwardSearch = true,
Filter = filter
}).GetRemainingAsync();
IterateList(profiles);
Console.WriteLine("\n\nQuery where email in '*****@*****.**', '*****@*****.**' sorted descending");
profiles = await _context.QueryAsync <Profile>("ID", new DynamoDBOperationConfig
{
QueryFilter = new List <ScanCondition>
{
new ScanCondition(nameof(Profile.Email), ScanOperator.In, "*****@*****.**", "*****@*****.**")
},
BackwardQuery = true
}).GetRemainingAsync();
IterateList(profiles);
}
public List <T> GetItem <T>(string filterType, string filterValue)
{
List <AttributeValue> eqListAvailable = new List <AttributeValue>();
eqListAvailable.Add(new AttributeValue()
{
N = "1"
});
QueryFilter queryFilter = new QueryFilter();
List <AttributeValue> eqList = new List <AttributeValue>();
eqList.Add(new AttributeValue()
{
S = filterValue
});
queryFilter.AddCondition(filterType, new Condition()
{
ComparisonOperator = ComparisonOperator.EQ,
AttributeValueList = eqList
});
queryFilter.AddCondition(pseudoDeleteAttributeName, new Condition()
{
AttributeValueList = eqListAvailable,
ComparisonOperator = ComparisonOperator.EQ
});
QueryOperationConfig config = filterType == "Name" ? new QueryOperationConfig()
{
Filter = queryFilter
} : new QueryOperationConfig()
{
IndexName = filterType, Filter = queryFilter
};
var list = _dynamoDBContext.FromQueryAsync <T>(config).GetRemainingAsync().Result;
return(list);
//Easy way to query by primary(hash) key
//IEnumerable<T> list = _dynamoDBContext.QueryAsync<T>(name).GetRemainingAsync().Result;
//return list;
}
private async Task <IEnumerable <MessageItem> > PageAllMessagesAsync(QueryOperationConfig queryConfig)
{
var asyncSearch = _context.FromQueryAsync <MessageItem>(queryConfig);
var messages = new List <MessageItem>();
do
{
messages.AddRange(await asyncSearch.GetNextSetAsync().ConfigureAwait(ContinueOnCapturedContext));
} while (!asyncSearch.IsDone);
return(messages);
}
private async Task <IEnumerable <CommandItem <T> > > PageAllMessagesAsync <T>(QueryOperationConfig queryConfig)
where T : class, IRequest
{
var asyncSearch = _context.FromQueryAsync <CommandItem <T> >(queryConfig);
var messages = new List <CommandItem <T> >();
do
{
messages.AddRange(await asyncSearch.GetNextSetAsync().ConfigureAwait(false));
} while (!asyncSearch.IsDone);
return(messages);
}
public async Task <List <T> > Get <T>(object key)
{
using (var context = new DynamoDBContext(_client))
{
if (typeof(T) == typeof(Network))
{
var queryOperation = context.FromQueryAsync <T>(new QueryOperationConfig()
{
IndexName = "Network_Global_Index_01",
KeyExpression = new Expression()
{
ExpressionStatement = "MasterId = :mid", ExpressionAttributeValues = new Dictionary <string, DynamoDBEntry>()
{
{ ":mid", key.ToString() }
}
},
AttributesToGet = new List <string>()
{
"Name", "Code", "Tags", "Id", "MasterId"
},
Select = SelectValues.SpecificAttributes
});
return(await queryOperation.GetRemainingAsync());
}
else
{
var queryOperation = context.FromQueryAsync <T>(new QueryOperationConfig()
{
ConsistentRead = true,
Filter = new QueryFilter("MasterId", QueryOperator.Equal, key.ToString())
});
return(await queryOperation.GetRemainingAsync());
}
}
}
/// <summary>
/// Multiple Query using Object Persistence Model
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
public async Task <List <Widget> > GetWidgetsByQueryUsingOP(string id)
{
if (string.IsNullOrEmpty(id))
{
id = "WDGT1";
}
var queryfilter = new QueryOperationConfig()
{
IndexName = "Id-Created-index",
Filter = new QueryFilter("Id", QueryOperator.Equal, id)
};
var query = _context.FromQueryAsync <Widget>(queryfilter);
return(await query.GetRemainingAsync());
}
public IList <PlayerStat> GetPlayerStats(string id)
{
DynamoDBContext context = new DynamoDBContext(_client);
QueryFilter filter = new QueryFilter();
filter.AddCondition("UserName", QueryOperator.Equal, id);
QueryOperationConfig queryOperationConfig = new QueryOperationConfig {
Filter = filter
};
var result = context.FromQueryAsync <PlayerStat>(queryOperationConfig).GetNextSetAsync().GetAwaiter().GetResult();
return(result);
}
public IList <PlayerStat> GetPlayerStats(string id, int duration)
{
DynamoDBContext context = new DynamoDBContext(_client);
QueryFilter filter = new QueryFilter();
filter.AddCondition("UserName", QueryOperator.Equal, id);
filter.AddCondition("TimeStamp", QueryOperator.GreaterThanOrEqual, DateTime.Now.AddHours(-duration));
QueryOperationConfig queryOperationConfig = new QueryOperationConfig {
Filter = filter
};
var result = context.FromQueryAsync <PlayerStat>(queryOperationConfig).GetNextSetAsync().GetAwaiter().GetResult();
return(result);
}
public async Task <bool> Exists <T>(AttributeValue key) where T : IAwsDbItem, new()
{
var filter = new QueryFilter();
filter.AddCondition(new T().GetIdFieldName(), ScanOperator.Equal, new List <AttributeValue>()
{
key
});
var iterator = _context.FromQueryAsync <T>(new QueryOperationConfig()
{
Filter = filter
});
var results = await iterator.GetRemainingAsync();
return(results.Count > 0);
}
public Task <List <User> > GetUsersByClientIdAsync(string id)
{
var userQuery = new Amazon.DynamoDBv2.DocumentModel.QueryOperationConfig
{
IndexName = "ClientId-index"
};
userQuery.KeyExpression = new Amazon.DynamoDBv2.DocumentModel.Expression
{
ExpressionStatement = "ClientId = :clientId",
ExpressionAttributeValues = new Dictionary <string, Amazon.DynamoDBv2.DocumentModel.DynamoDBEntry>
{
{ ":clientId", id }
}
};
var botresult = _context.FromQueryAsync <User>(userQuery);
return(botresult.GetRemainingAsync());
}
protected virtual async Task <object> GetLastSortKey(string hashKeyFieldName, string hashKeyValue, string sortKeyFieldName)
{
var queryConfig = new QueryOperationConfig()
{
BackwardSearch = true,
Limit = 1,
Filter = new QueryFilter(hashKeyFieldName, QueryOperator.Equal, hashKeyValue)
};
var results = await Context.FromQueryAsync <TEntity>(queryConfig).GetNextSetAsync();
var lastItem = results.FirstOrDefault();
if (lastItem == null)
{
return(null);
}
var keyProperty = lastItem.GetType().GetProperty(sortKeyFieldName);
if (keyProperty == null)
{
throw new ArgumentException($"Sort key name ({sortKeyFieldName}) is invalid for entity {lastItem.GetType().ToString()}");
}
return(keyProperty.GetValue(lastItem, null));
}
public async Task <IEnumerable <BackerListModel> > Handle(GetBackersListQuery request, CancellationToken cancellationToken)
{
var results = new List <Backer>();
using var context = new DynamoDBContext(_dynamoDb);
var response = context.FromQueryAsync <Backer>(new QueryOperationConfig
{
AttributesToGet = new List <string> {
nameof(Backer.Id), nameof(Backer.Name), nameof(Backer.EmailAddress), nameof(Backer.Amount)
},
Select = SelectValues.SpecificAttributes,
KeyExpression = new Expression
{
ExpressionStatement = "begins_with(Id,:eventId) AND DomainType = :domainType",
ExpressionAttributeValues = new Dictionary <string, DynamoDBEntry> {
{ ":eventId", new Primitive($"{request.EventId}-{request.ParticipantId}") }, { ":domainType", new Primitive(nameof(Backer)) }
}
}
});
results.AddRange(await response.GetRemainingAsync(cancellationToken));
return(results.Select(x => _mapper.Map(x, new BackerListModel())));
}
public async Task <IEnumerable <EventListModel> > Handle(GetEventsListQuery request, CancellationToken cancellationToken)
{
var results = new List <Event>();
using var context = new DynamoDBContext(_dynamoDb);
var response = context.FromQueryAsync <Event>(new QueryOperationConfig
{
AttributesToGet = new List <string> {
nameof(Event.Id), nameof(Event.Name), nameof(Event.StartDate), nameof(Event.City)
},
Select = SelectValues.SpecificAttributes,
KeyExpression = new Expression
{
ExpressionStatement = "Id > :id AND DomainType = :domainType",
ExpressionAttributeValues = new Dictionary <string, DynamoDBEntry> {
{ ":id", new Primitive("0") }, { ":domainType", new Primitive(nameof(Event)) }
}
}
});
results.AddRange(await response.GetRemainingAsync(cancellationToken));
return(results.Select(x => _mapper.Map(x, new EventListModel())));
}
//******
//****** Adapted from the Query and Scan section in https://docs.aws.amazon.com/mobile/sdkforxamarin/developerguide/dynamodb-integration-objectpersistencemodel.html
/// <summary>
/// Reads items where the contents of the field is equal to the query string. This method is async.
/// </summary>
/// <returns>A List of items.</returns>
/// <param name="fieldToQuery">Field to query.</param>
/// <param name="queryString">Query string.</param>
public async Task <List <Item> > ReadItemEqualAsync(string fieldToQuery, string queryString)
{
if (string.IsNullOrEmpty(queryString))
{
List <Item> blankResponse = new List <Item>
{
new Item
{
Id = "Nothing to retrieve",
SavedTimeStamp = "Nothing to retrieve",
Name = "Nothing to retrieve",
Email = "Nothing to retrieve",
Password = "******"
}
};
RetrievedItemDataStore.Instance().retrievedName = "Nothing to retrieve"; //Is it necessary to store the UserNameToRetrieveText?
RetrievedItemDataStore.Instance().id = "Nothing to retrieve";
RetrievedItemDataStore.Instance().savedTimeStamp = "Nothing to retrieve";
RetrievedItemDataStore.Instance().name = "Nothing to retrieve";
RetrievedItemDataStore.Instance().email = "Nothing to retrieve";
RetrievedItemDataStore.Instance().password = "******";
return(blankResponse); //An error of "value cannot be null" will be thrown in the viewmodel if the queryString is null.
//So FromQueryAsync() isn't executed if queryString is null.
}
//var client = new AmazonDynamoDBClient(_credentials, RegionEndpoint.USEast2);
//DynamoDBContext context = new DynamoDBContext(client);
//QueryFilter queryFilter = null;
//switch (queryOperator)
//{
// case "Equal":
// queryFilter = new QueryFilter(fieldToQuery, QueryOperator.Equal, queryString);
// break;
// case "GreaterThan":
// queryFilter = new QueryFilter(fieldToQuery, QueryOperator.GreaterThan, queryString);
// break;
// case "GreaterThanOrEqual":
// queryFilter = new QueryFilter(fieldToQuery, QueryOperator.GreaterThanOrEqual, queryString);
// break;
// case "LessThan":
// queryFilter = new QueryFilter(fieldToQuery, QueryOperator.LessThan, queryString);
// break;
// case "LessThanOrEqual":
// queryFilter = new QueryFilter(fieldToQuery, QueryOperator.LessThanOrEqual, queryString);
// break;
// case "BeginsWith":
// queryFilter = new QueryFilter(fieldToQuery, QueryOperator.BeginsWith, queryString);
// break;
// case "Between":
// queryFilter = new QueryFilter(fieldToQuery, QueryOperator.Between, queryString);
// break;
//}
var search = _context.FromQueryAsync <Item>(new QueryOperationConfig()
{
//IndexName = "Name-index", //Taken from the DynamoDB dashboard when creating the Global Secondary Index.
//Filter = new QueryFilter("Name", QueryOperator.Equal, "AwsDynamoDbTest app started")
IndexName = fieldToQuery + "-index", //Taken from the DynamoDB dashboard when creating the Global Secondary Index.
Filter = new QueryFilter(fieldToQuery, QueryOperator.Equal, queryString)
});
#if DEBUG
//System.Diagnostics.Debug.WriteLine("QueryAsync() items retrieved:");
int count = 0;
var searchResponse = await search.GetRemainingAsync();
string itemData = null;
searchResponse.ForEach((item) =>
{
count++;
//System.Diagnostics.Debug.WriteLine(count + ". " + "Name = " + item.Name + ", Password = "******", Id = " + item.Id + ", SavedTimeStamp = " + item.SavedTimeStamp);
itemData += count + ". " + "Name = " + item.Name + ", Password = "******", Id = " + item.Id + ", SavedTimeStamp = " + item.SavedTimeStamp + "\n";
});
System.Diagnostics.Debug.WriteLine("ReadItemEqualAsync() retrieved " + count + " items:\n" + itemData);
count = 0;
#endif
return(searchResponse);
}
