Add dart snippets (#5)

* Add dart snippets

* Remove listPaymentsFiltered

* Target published Dart/Flutter packages on git repository by default

* Fix imports

* Add BreezLiquidSDK wrapper class to manage wallet instance & SDK streams

* Add rxdart

* [Dart] Initialize Liquid SDK library

* [Dart] Update LNURL snippets

* [Dart] Update Fiat Currency snippets

* CI: update references to breez-liquid-sdk

* Flutter setup instructions: update repo links

* Dart snippets: rewrite to match Rust snippets

* CI: Update default SDK ref and package version

* Address linter issues and run dart format

* Add extension on Config
* Fix indentation
* Fix enum name
* Add print statements to remove unused_variable warnings
* Remove unused import

* CI: Re-add default value for sdk-ref

* Dart setup: add hint about initialization approach

* Dart setup: update hint with more details

* Update link syntax

---------

Co-authored-by: Erdem Yerebasmaz <[email protected]>

.github/workflows/main.yml

@@ -11,10 +11,10 @@ on:
   workflow_dispatch:
     inputs:
       sdk-ref:
-        description: 'sdk commit/tag/branch reference. Defaults to main.'
+        description: 'sdk commit/tag/branch reference. Defaults to 0.1.2-dev4.'
         required: false
         type: string
-        default: main
+        default: 0.1.2-dev4
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
@@ -25,17 +25,19 @@ jobs:
     name: setup
     runs-on: ubuntu-latest
     outputs:
-      sdk-ref: ${{ inputs.sdk-ref || '08b2e5a6e2e095a8aaa1cdb7650b3b1b7348dc65' }}
-      package-version: '0.1.1'
+      # Used only for Rust snippets
+      sdk-ref: ${{ inputs.sdk-ref || '0.1.2-dev4' }}
+      # Used for RN and Flutter snippets
+      package-version: '0.1.2-dev4'
     steps:
       - run: echo "set pre-setup output variables"
 
   build-packages:
     needs: setup
     name: build packages
-    uses: breez/breez-sdk/.github/workflows/publish-all-platforms.yml@main
+    uses: breez/breez-liquid-sdk/.github/workflows/publish-all-platforms.yml@main
     with:
-      repository: breez/breez-sdk
+      repository: breez/breez-liquid-sdk
       ref: ${{ needs.setup.outputs.sdk-ref }}
       package-version: ${{ needs.setup.outputs.package-version }}
       packages-to-publish: '["csharp", "flutter", "golang", "react-native", "python"]'
@@ -110,8 +112,8 @@ jobs:
 
       - uses: actions/download-artifact@v4
         with:
-          name: breez-sdk-flutter-${{ needs.setup.outputs.package-version }}
-          path: snippets/dart_snippets/packages/breez-sdk-flutter
+          name: breez-liquid-sdk-flutter-${{ needs.setup.outputs.package-version }}
+          path: snippets/dart_snippets/packages/breez-liquid-sdk-flutter
 
       - name: pub-get
         working-directory: snippets/dart_snippets

snippets/dart_snippets/.gitignore

@@ -0,0 +1,7 @@
+# https://dart.dev/guides/libraries/private-files
+# Created by `dart pub`
+.dart_tool/
+packages/
+.flutter-version
+.flutter-plugins
+.flutter-plugins-dependencies

snippets/dart_snippets/README.md

@@ -0,0 +1,11 @@
+## Steps to compile the snippets locally
+1. Build a flutter package
+  - By running the publish-all-platforms CI in the breez-liquid-sdk repository (use dummy binaries)
+  - or by cloning https://github.com/breez/breez-liquid-sdk-flutter
+2. Place the files in the folder `snippets/dart-snippets/packages/breez-liquid-sdk-flutter`
+3. Happy coding
+
+To use a local path to the flutter bindings, see the `dependency_overrides` section in `pubspec.yaml`.
+
+## Nix
+Use the command `nix develop`

snippets/dart_snippets/analysis_options.yaml

@@ -0,0 +1,30 @@
+# This file configures the static analysis results for your project (errors,
+# warnings, and lints).
+#
+# This enables the 'recommended' set of lints from `package:lints`.
+# This set helps identify many issues that may lead to problems when running
+# or consuming Dart code, and enforces writing Dart using a single, idiomatic
+# style and format.
+#
+# If you want a smaller set of lints you can change this to specify
+# 'package:lints/core.yaml'. These are just the most critical lints
+# (the recommended set includes the core lints).
+# The core lints are also what is used by pub.dev for scoring packages.
+
+include: package:lints/recommended.yaml
+
+# Uncomment the following section to specify additional rules.
+
+# linter:
+#   rules:
+#     - camel_case_types
+
+analyzer:
+  exclude:
+    - packages/**
+
+# For more information about the core and recommended set of lints, see
+# https://dart.dev/go/core-lints
+
+# For additional information about configuring this file, see
+# https://dart.dev/guides/language/analysis-options

snippets/dart_snippets/bin/dart_snippets.dart

@@ -0,0 +1,6 @@
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart' as liquid_sdk;
+
+void main() async {
+  // Initialize library
+  await liquid_sdk.initialize();
+}

snippets/dart_snippets/flake.nix

@@ -0,0 +1,26 @@
+{
+  description = "Flutter flake";
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-24.05";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+  outputs =
+    { self
+    , nixpkgs
+    , flake-utils
+    ,
+    }:
+    flake-utils.lib.eachDefaultSystem (system:
+    let
+      pkgs = nixpkgs.legacyPackages.${system};
+    in
+    {
+      devShells.default = pkgs.mkShell {
+        buildInputs = with pkgs; [
+          flutter
+        ];
+      };
+
+      formatter = pkgs.nixpkgs-fmt;
+    });
+}

snippets/dart_snippets/lib/fiat_currencies.dart

@@ -0,0 +1,22 @@
+import 'package:dart_snippets/sdk_instance.dart';
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart';
+
+Future<List<FiatCurrency>> listFiatCurrencies() async {
+  // ANCHOR: list-fiat-currencies
+  List<FiatCurrency> fiatCurrencyList = await breezLiquidSDK.instance!.listFiatCurrencies();
+  // ANCHOR_END: list-fiat-currencies
+  return fiatCurrencyList;
+}
+
+Future<Map<String, Rate>> fetchFiatRates() async {
+  // ANCHOR: fetch-fiat-rates
+  final List<Rate> rates = await breezLiquidSDK.instance!.fetchFiatRates();
+  final fiatRatesMap = rates.fold<Map<String, Rate>>({}, (map, rate) {
+    map[rate.coin] = rate;
+    return map;
+  });
+  // print your desired rate
+  print(fiatRatesMap["USD"]?.value);
+  // ANCHOR_END: fetch-fiat-rates
+  return fiatRatesMap;
+}

snippets/dart_snippets/lib/getting_started.dart

@@ -0,0 +1,50 @@
+import 'package:dart_snippets/sdk_instance.dart';
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart';
+
+Future<void> initializeSDK() async {
+  // ANCHOR: init-sdk
+  // It is recommended to use a single instance of BreezSDKLiquid across your Dart/Flutter app.
+  //
+  // All of the snippets assume a BreezSDKLiquid object is created on entrypoint of the app as such:
+  //
+  // ConnectRequest req = ConnectRequest(...);
+  // BindingLiquidSdk instance = await connect(req: req);
+  //
+  // and is accessible throughout the app. There are various approaches on how to achieve this:
+  // creating a Singleton class using factory constructor, using state management libraries such as 'provider', 'GetX',
+  // 'Riverpod' and 'Redux' to name a few.
+  //
+  // The Dart snippets included here rely on the example approach seen on sdk_instance.dart to manage wallet connection
+  // and Liquid SDK streams. This approach also has essential helper methods to ensure wallet data is in sync.
+  // Please see sdk_instance.dart for more details:
+  // [sdk_instance.dart](https://github.com/breez/breez-sdk-liquid-docs/blob/main/snippets/dart_snippets/lib/sdk_instance.dart)
+
+  // Create the default config
+  String mnemonic = "<mnemonic words>";
+
+  // Create the default config
+  Config config = defaultConfig(
+    network: LiquidNetwork.mainnet,
+  );
+
+  // Customize the config object according to your needs
+  config = config.copyWith(workingDir: "path to an existing directory");
+
+  ConnectRequest connectRequest = ConnectRequest(mnemonic: mnemonic, config: config);
+
+  await breezLiquidSDK.connect(req: connectRequest);
+
+  // ANCHOR_END: init-sdk
+}
+
+Future<void> fetchBalance(String lspId) async {
+  // ANCHOR: fetch-balance
+  GetInfoResponse? nodeState = await breezLiquidSDK.instance!.getInfo();
+  BigInt balanceSat = nodeState.balanceSat;
+  BigInt pendingSendSat = nodeState.pendingSendSat;
+  BigInt pendingReceiveSat = nodeState.pendingReceiveSat;
+  // ANCHOR_END: fetch-balance
+  print(balanceSat);
+  print(pendingSendSat);
+  print(pendingReceiveSat);
+}

snippets/dart_snippets/lib/list_payments.dart

@@ -0,0 +1,9 @@
+import 'package:dart_snippets/sdk_instance.dart';
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart';
+
+Future<List<Payment>> listPayments() async {
+  // ANCHOR: list-payments
+  List<Payment> paymentsList = await breezLiquidSDK.instance!.listPayments();
+  // ANCHOR_END: list-payments
+  return paymentsList;
+}

snippets/dart_snippets/lib/lnurl_auth.dart

@@ -0,0 +1,21 @@
+import 'package:dart_snippets/sdk_instance.dart';
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart';
+
+Future<void> lnurlAuth() async {
+  // ANCHOR: lnurl-auth
+  /// Endpoint can also be of the form:
+  /// keyauth://domain.com/auth?key=val
+  String lnurlAuthUrl =
+      "lnurl1dp68gurn8ghj7mr0vdskc6r0wd6z7mrww4excttvdankjm3lw3skw0tvdankjm3xdvcn6vtp8q6n2dfsx5mrjwtrxdjnqvtzv56rzcnyv3jrxv3sxqmkyenrvv6kve3exv6nqdtyv43nqcmzvdsnvdrzx33rsenxx5unqc3cxgeqgntfgu";
+
+  InputType inputType = await parse(input: lnurlAuthUrl);
+  if (inputType is InputType_LnUrlAuth) {
+    LnUrlCallbackStatus result = await breezLiquidSDK.instance!.lnurlAuth(reqData: inputType.data);
+    if (result is LnUrlCallbackStatus_Ok) {
+      print("Successfully authenticated");
+    } else {
+      print("Failed to authenticate");
+    }
+  }
+  // ANCHOR_END: lnurl-auth
+}

snippets/dart_snippets/lib/lnurl_pay.dart

@@ -0,0 +1,26 @@
+import 'package:dart_snippets/sdk_instance.dart';
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart';
+
+Future<void> lnurlPay() async {
+  // ANCHOR: lnurl-pay
+  /// Endpoint can also be of the form:
+  /// lnurlp://domain.com/lnurl-pay?key=val
+  /// lnurl1dp68gurn8ghj7mr0vdskc6r0wd6z7mrww4excttsv9un7um9wdekjmmw84jxywf5x43rvv35xgmr2enrxanr2cfcvsmnwe3jxcukvde48qukgdec89snwde3vfjxvepjxpjnjvtpxd3kvdnxx5crxwpjvyunsephsz36jf
+  String lnurlPayUrl = "[email protected]";
+
+  InputType inputType = await parse(input: lnurlPayUrl);
+  if (inputType is InputType_LnUrlPay) {
+    BigInt amountMsat = inputType.data.minSendable;
+    String optionalComment = "<comment>";
+    String optionalPaymentLabel = "<label>";
+    LnUrlPayRequest req = LnUrlPayRequest(
+      data: inputType.data,
+      amountMsat: amountMsat,
+      comment: optionalComment,
+      paymentLabel: optionalPaymentLabel,
+    );
+    LnUrlPayResult result = await breezLiquidSDK.instance!.lnurlPay(req: req);
+    print(result.data);
+  }
+  // ANCHOR_END: lnurl-pay
+}

snippets/dart_snippets/lib/lnurl_withdraw.dart

@@ -0,0 +1,23 @@
+import 'package:dart_snippets/sdk_instance.dart';
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart';
+
+Future<void> lnurlWithdraw() async {
+  // ANCHOR: lnurl-withdraw
+  /// Endpoint can also be of the form:
+  /// lnurlw://domain.com/lnurl-withdraw?key=val
+  String lnurlWithdrawUrl =
+      "lnurl1dp68gurn8ghj7mr0vdskc6r0wd6z7mrww4exctthd96xserjv9mn7um9wdekjmmw843xxwpexdnxzen9vgunsvfexq6rvdecx93rgdmyxcuxverrvcursenpxvukzv3c8qunsdecx33nzwpnvg6ryc3hv93nzvecxgcxgwp3h33lxk";
+
+  InputType inputType = await parse(input: lnurlWithdrawUrl);
+  if (inputType is InputType_LnUrlWithdraw) {
+    BigInt amountMsat = inputType.data.minWithdrawable;
+    LnUrlWithdrawRequest req = LnUrlWithdrawRequest(
+      data: inputType.data,
+      amountMsat: amountMsat,
+      description: "<description>",
+    );
+    LnUrlWithdrawResult result = await breezLiquidSDK.instance!.lnurlWithdraw(req: req);
+    print(result.data);
+  }
+  // ANCHOR_END: lnurl-withdraw
+}

snippets/dart_snippets/lib/pay_onchain.dart

@@ -0,0 +1,42 @@
+import 'package:dart_snippets/sdk_instance.dart';
+import 'package:flutter_breez_liquid/flutter_breez_liquid.dart';
+
+Future<OnchainPaymentLimitsResponse> getCurrentLimits() async {
+  // ANCHOR: get-current-pay-onchain-limits
+  OnchainPaymentLimitsResponse currentLimits = await breezLiquidSDK.instance!.fetchOnchainLimits();
+  print("Minimum amount: ${currentLimits.send.minSat} sats");
+  print("Maximum amount: ${currentLimits.send.maxSat} sats");
+  // ANCHOR_END: get-current-pay-onchain-limits
+  return currentLimits;
+}
+
+Future<PreparePayOnchainResponse> preparePayOnchain() async {
+  // ANCHOR: prepare-pay-onchain
+  PreparePayOnchainRequest preparePayOnchainRequest = PreparePayOnchainRequest(
+    receiverAmountSat: 5000 as BigInt,
+  );
+  PreparePayOnchainResponse prepareRes = await breezLiquidSDK.instance!.preparePayOnchain(
+    req: preparePayOnchainRequest,
+  );
+
+  // Check if the fees are acceptable before proceeding
+  BigInt feesSat = prepareRes.feesSat;
+  // ANCHOR_END: prepare-pay-onchain
+  print(feesSat);
+  return prepareRes;
+}
+
+Future<SendPaymentResponse> startReverseSwap({
+  required PreparePayOnchainResponse prepareRes,
+}) async {
+  // ANCHOR: start-reverse-swap
+  String destinationAddress = "bc1..";
+
+  PayOnchainRequest req = PayOnchainRequest(
+    address: destinationAddress,
+    prepareRes: prepareRes,
+  );
+  SendPaymentResponse res = await breezLiquidSDK.instance!.payOnchain(req: req);
+  // ANCHOR_END: start-reverse-swap
+  return res;
+}