dvote 0.12.17

Decentralized, end-to-end verifiable governance platform client library for Dart.

DVote Flutter

A Flutter plugin that provides cryptographic and communication capabilities to interact with decentralized governance processes running on the Vocdoni platform.

It provides Dart libraries as well as native modules written in Go.

More details: https://pub.dev/packages/dvote

DVote example

• Getting Started
• HD Wallet management
• Signing
• Encryption
• Entity API
• File API
• Data models

Getting Started

Import the Dart library on your project and use the static functions available on the Dvote class

import 'package:dvote/dvote.dart';

HD Wallet management

Generating mnemonics and computing private/public keys

final wallet = EthereumWallet.random(hdPath: "m/44'/60'/0'/0/5");
final mnemonic = wallet.mnemonic;
final privKey = wallet.privateKey;
final pubKey = wallet.publicKey;
final addr = wallet.address;

Signing

Computing signatures using ECDSA cryptography

// Signing plain text
final hexSignature = signString(messageToSign, privateKey);
final recoveredPubKey = recoverSignerPubKey(hexSignature, messageToSign);
final valid = isValidSignature(hexSignature, messageToSign, publicKey);

// Signing reproduceable JSON data
final hexSignature2 = signJsonPayload({"hello": 1234}, privateKey);
final recoveredPubKey = recoverJsonSignerPubKey(hexSignature2, {"hello": 1234});
final valid2 = isValidJsonSignature(hexSignature2, {"hello": 1234}, publicKey);

Also available as async non-UI blocking functions:

// Signing plain text
final hexSignature = await signStringAsync(messageToSign, privateKey);
final recoveredPubKey = await recoverSignerPubKeyAsync(hexSignature, messageToSign);
final valid = await isValidSignatureAsync(hexSignature, messageToSign, publicKey);

// Signing reproduceable JSON data
final hexSignature2 = await signJsonPayloadAsync({"hello": 1234}, privateKey);
final recoveredPubKey = await recoverJsonSignerPubKeyAsync(hexSignature2, {"hello": 1234});
final valid2 = await isValidJsonSignatureAsync(hexSignature2, {"hello": 1234}, publicKey);

Entity API

Use a Vocdoni Gateway to fetch the metadata of an Entity

import 'package:dvote/dvote.dart';

EntityReference entityRef = EntityReference();
entityRef.entityId = "0x1234...";

final gwInfo = await getRandomDefaultGatewayInfo("goerli");
final DVoteGateway dvoteGw = DVoteGateway(gwInfo.dvote, publicKey: gwInfo.publicKey);
final Web3Gateway web3Gw = Web3Gateway(gwInfo.web3);

final entityMeta = await fetchEntity(entityRef, dvoteGw, web3Gw);
dvoteGw.disconnect();

Process API

Use a Vocdoni Gateway to fetch the active voting processes of an Entity

import 'package:dvote/dvote.dart';

EntityReference entityRef = EntityReference();
entityRef.entityId = "0x1234...";

final gwInfo = await getRandomDefaultGatewayInfo("goerli");
final DVoteGateway dvoteGw = DVoteGateway(gwInfo.dvote, publicKey: gwInfo.publicKey);
final Web3Gateway web3Gw = Web3Gateway(gwInfo.web3);

// All active from an Entity
final List<ProcessMetadata>> processes = await fetchActiveProcesses(entityRef, dvoteGw, web3Gw);

// A specific Voting Process
final pid = "0x1234...";
final ProcessMetadataprocessMeta = await getProcessMetadata(pid, dvoteGw, web3Gw);

dvoteGw.disconnect();

File API

Use a Vocdoni Gateway to fetch static content from the net

import 'package:dvote/dvote.dart';

final gwInfo = await getRandomDefaultGatewayInfo("goerli");
final DVoteGateway dvoteGw = DVoteGateway(gwInfo.dvote, publicKey: gwInfo.publicKey);
final Web3Gateway web3Gw = Web3Gateway(gwInfo.web3);

final contentUri = ContentURI("ipfs://QmSsfizN4rpSDLRZw3X3WooCPpnBktZ5bEShvmLZuf88iw,https://my-server/file.txt");

final content = await fetchFileString(contentUri, dvoteGw, web3Gw);

Data models and storage

DVote Flutter exports multiple Dart classes that allow to wrap, parse, serialize and deserialize the most relevant data schemes used within the platform.

import 'package:dvote/dvote.dart';

// Parse from JSON
Entity entity = parseEntityMetadata("{ ... }");
print(entity.name["en"]);
print(entity.media.avatar);

// Serialize into a binary file
File file1 = File("./my-entity.dat");
file1.writeAsBytes(entity.writeToBuffer());

// Reading back from a file
File file3 = File("./my-entity.dat");
final entityBytes = await file3.readAsBytes();
Entity entity2 = Entity.fromBuffer(entityBytes);
print(entity2.name["en"]);

// Storing a collection of entities
EntitiesStore store = EntitiesStore();
store.entities.addAll([entity, entity2]);
File file2 = File("./entities.dat");
await file2.writeAsBytes(store.writeToBuffer());

Classes

The following classes are exported:

• Entity
  • EntityStore
  • Entity_VotingProcesses
  • Entity_Media
  • Entity_Action_ImageSource
  • Entity_Action
  • Entity_GatewayBootNode
  • Entity_GatewyUpdate
  • Entity_Relay
  • Entity_EntityReference
  • EntitySummary
• Process
  • Process_Census
  • Process_Details
  • Process_Details_Question
  • Process_Details_Question_VoteOption
• Feed
  • FeedsStore
  • FeedPost_Author
  • FeedPost
• Gateway
  • GatewaysStore
• Identity
  • IdentitiesStore
  • Identity_Claim
• Key

Parsers

Raw JSON data can't be directly serialized into a Protobuf object. For this reason, several parsers are provided:

• Entity parseEntityMetadata(String json)
  • List<Entity_Action> parseEntityActions(List actions)
  • List<Entity_GatewayBootNode> parseBootNodes(List bootNodes)
  • List<Entity_EntityReference> parseEntityReferences(List entities)
• Process parseProcessMetadata(String json)
  • List<Process_Details_Question> parseQuestions(List items)
• Feed parseFeed(String json)

Example

• See example/lib/main.dart for a usage example.

Development

• Clone the git repo
• Run flutter pub get
• Run submodule update --init --recursive to fetch the protobuf subrepo

TO DO

• ❌ Document examples of Poseidon hash, generate Merkle Proofs and ZK proofs