Search…
Graffle Flow SDK
The Graffle Flow SDK is a C# SDK that abstracts away the gRPC calls to interact with the Flow blockchain. https://github.com/Graffle/flow-c-sharp-graffle-sdk

Create client:

var flowClientFactory = new FlowClientFactory(nodeName);
var flowClient = flowClientFactory.CreateFlowClient();

Get latest block:

var latestBlock = flowClient.GetLatestBlockAsync();

Get latest sealed block:

var latestBlock = await flowClient.GetLatestBlockAsync(true);

Search a block range for a specific event:

var eventId = "A.c1e4f4f4c4257510.Market.MomentPurchased";
ulong startBlock = 22037959;
ulong endBlock = 22037961;
var eventsResponse = await flowClient.GetEventsForHeightRangeAsync(eventId, startBlock, endBlock);

Execute script at block id:

var latestBlockResponse = await this.flowClient.GetLatestBlockAsync(true);
var helloWorldScript = @"
pub fun main(): String {
return ""Hello World""
}
";
var scriptBytes = Encoding.ASCII.GetBytes(helloWorldScript);
var scriptResponse = await flowClient.ExecuteScriptAtBlockIdAsync(latestBlockResponse.Id.HashToByteString(), scriptBytes, new List<FlowValueType>());
var metaDataJson = Encoding.Default.GetString(scriptResponse.Value.ToByteArray());
var result = StringType.FromJson(metaDataJson);

Execute script at block height:

var latestBlockResponse = await this.flowClient.GetLatestBlockAsync(true);
var helloWorldScript = @"
pub fun main(): String {
return ""Hello World""
}
";
var scriptBytes = Encoding.ASCII.GetBytes(helloWorldScript);
var scriptResponse = await flowClient.ExecuteScriptAtBlockIdAsync(latestBlockResponse.Height, scriptBytes, new List<FlowValueType>());
var metaDataJson = Encoding.Default.GetString(scriptResponse.Value.ToByteArray());
var result = StringType.FromJson(metaDataJson);

Get block at height

var blockResponse = await flowClient.GetBlockByHeightAsync(blockHeight);

Get a transaction within a block

var block = await flowClient.GetBlockByHeightAsync(blockHeight);
var collectionId = block.CollectionGuarantees.FirstOrDefault().CollectionId;
var collection = await flowClient.GetCollectionById(collectionId.HashToByteString());
var transactionId = collection.TransactionIds.FirstOrDefault();
var transactionResult = await flowClient.GetTransactionResult(transactionId.HashToByteString());
var transaction = await flowClient.GetTransactionAsync(transactionId.HashToByteString());

Get account at block height

var account = await flowClient.GetAccountAsync(addressHex, blockHeight)

Get collection by Id

var collection = await flowClient.GetCollectionById(collectionId.HashToByteString());

Create a new account

//example given using emulator account, load real account from flow.json for working with MainNet or TestNet
var emulatorAccount = await flowClient.GetAccountFromConfigAsync("emulator-account");
var emulatorAccountKey = emulatorAccount.Keys[0];
var flowAccountKey = Flow.Entities.AccountKey.GenerateRandomEcdsaKey(SignatureAlgorithm.ECDSA_P256, HashAlgorithm.SHA3_256);
var newFlowAccountKeys = new List<Flow.Entities.AccountKey> { flowAccountKey };
var latestBlock = await flowClient.GetLatestBlockAsync();
var emulatorAddress = new FlowAddress(emulatorAccount.Address);
var transaction = AccountTransactions.CreateAccount(newFlowAccountKeys, emulatorAddress);
transaction.Payer = emulatorAddress;
transaction.ProposalKey = new FlowProposalKey
{
Address = emulatorAddress,
KeyId = emulatorAccountKey.Index,
SequenceNumber = emulatorAccountKey.SequenceNumber
};
transaction.ReferenceBlockId = latestBlock.Id;
// sign and submit the transaction
transaction = FlowTransaction.AddEnvelopeSignature(transaction, emulatorAddress, emulatorAccountKey.Index, emulatorAccountKey.Signer);
var response = await flowClient.SendTransactionAsync(transaction);
// wait for seal
var sealedResponse = await flowClient.WaitForSealAsync(response);
var createdEvent = sealedResponse.Events.FirstOrDefault(x => x.Type == "flow.AccountCreated");
string addressHex = createdEvent.EventComposite.Data.FirstOrDefault().Value.Substring(2);
var address = new FlowAddress(addressHex);
var latestBlock2 = await flowClient.GetLatestBlockAsync();
var account = await flowClient.GetAccountAsync(addressHex, latestBlock2.Height);
account.Keys = FlowAccountKey.UpdateFlowAccountKeys(newFlowAccountKeys.Select(x => new FlowAccountKey(x)).ToList(), account.Keys.ToList());

Send transaction

var emulatorAccount = await flowClient.GetAccountFromConfigAsync("emulator-account");
var emulatorAddress = new FlowAddress(emulatorAccount.Address);
var emulatorAccountKey = emulatorAccount.Keys[0];
var latestBlock = await flowClient.GetLatestBlockAsync();
var transaction = new FlowTransaction
{
Script = new FlowScript("transaction {}"),
ReferenceBlockId = latestBlock.Id,
Payer = emulatorAddress,
ProposalKey = new FlowProposalKey
{
Address = emulatorAddress,
KeyId = emulatorAccountKey.Index,
SequenceNumber = emulatorAccountKey.SequenceNumber
}
};
transaction = FlowTransaction.AddEnvelopeSignature(transaction, emulatorAddress, emulatorAccountKey.Index, emulatorAccountKey.Signer);
var response = await flowClient.SendTransactionAsync(transaction);
// wait for seal
var sealedResponse = await flowClient.WaitForSealAsync(response);

Copy link
On this page