Feature/contract

.eslintrc.js

@@ -0,0 +1,86 @@
+module.exports = {
+    env: {
+        node: true,
+        es2021: true
+    },
+    parser: '@typescript-eslint/parser',
+    extends: [
+        'plugin:@typescript-eslint/recommended'
+    ],
+    parserOptions: {
+        ecmaVersion: 13,
+        requireConfigFile: false
+    },
+    plugins: [
+        '@typescript-eslint',
+        'prefer-arrow'
+    ],
+    ignorePatterns: [
+        'node_modules'
+    ],
+    rules: {
+        'curly': ['error', 'multi-line'],
+        'no-implicit-coercion': ['error'],
+        'indent': ['error', 4, {
+            SwitchCase: 1,
+            MemberExpression: 1,
+            ArrayExpression: 1,
+            ObjectExpression: 1,
+            VariableDeclarator: 1,
+            CallExpression: {arguments: 1},
+            offsetTernaryExpressions: true
+        }],
+        'semi': ['error', 'always'],
+        'linebreak-style': ['error', 'unix'],
+        'no-fallthrough': 'off',
+        'no-console': 'off',
+        'no-debugger': 'error',
+        'max-len': ['warn', {
+            code: 100,
+            ignoreStrings: true,
+            ignoreRegExpLiterals: true,
+            ignoreTemplateLiterals: true,
+            tabWidth: 4,
+            ignoreComments: true
+        }],
+        'comma-dangle': ['error', 'never'],
+        'space-in-parens': ['error', 'never'],
+        'comma-spacing': 'error',
+        'object-curly-spacing': ['error', 'never'],
+        'object-curly-newline': ['error', {multiline: true}],
+        'array-bracket-spacing': ['error', 'never'],
+        'eqeqeq': ['error', 'always', {null: 'ignore'}],
+        'no-useless-call': 'error',
+        'prefer-promise-reject-errors': 'error',
+        'no-underscore-dangle': 'error',
+        'prefer-const': ['error', {destructuring: 'all', ignoreReadBeforeAssign: false}],
+        'no-bitwise': 'off',
+        'no-caller': 'error',
+        'no-useless-return': 'error',
+        'no-duplicate-imports': 'error',
+        'no-unused-expressions': 'error',
+        'arrow-body-style': ['error', 'as-needed'],
+        'prefer-arrow/prefer-arrow-functions': ['error', {
+            disallowPrototype: true,
+            singleReturnOnly: false,
+            classPropertiesAllowed: false
+        }],
+        'brace-style': ['error', '1tbs', {allowSingleLine: true}],
+        'space-infix-ops': ['error'],
+        'quote-props': ['error', 'consistent-as-needed'],
+        'no-multiple-empty-lines': ['warn', {max: 1, maxEOF: 0}],
+        'quotes': ['error', 'single', {allowTemplateLiterals: true}],
+        'no-eval': 'error',
+        'no-implied-eval': 'error',
+        '@typescript-eslint/no-var-requires': 'error',
+        '@typescript-eslint/ban-ts-comment': 'error',
+        '@typescript-eslint/no-non-null-assertion': 'off',
+        '@typescript-eslint/no-shadow': 'error',
+        '@typescript-eslint/no-this-alias': 'error',
+        '@typescript-eslint/no-empty-function': 'error',
+        'no-shadow': 'off',
+        '@typescript-eslint/no-unused-vars': 'error',
+        'no-unused-vars': 'off',
+        '@typescript-eslint/keyword-spacing': ['error']
+    }
+};

.gitignore

@@ -102,3 +102,12 @@ dist
 
 # TernJS port file
 .tern-port
+
+node_modules
+coverage.json
+typechain
+typechain-types
+
+#Hardhat files
+cache
+artifacts

.prettierrc.js

@@ -0,0 +1,10 @@
+module.exports = {
+    semi: true,
+    trailingComma: 'none',
+    singleQuote: true,
+    printWidth: 100,
+    tabWidth: 4,
+    useTabs: false,
+    bracketSpacing: false,
+    arrowParens: 'avoid'
+};

.solhint.json

@@ -0,0 +1,9 @@
+{
+  "extends": "solhint:recommended",
+  "plugins": [],
+  "rules": {
+    "avoid-suicide": "error",
+    "avoid-sha3": "warn",
+    "compiler-version": ["error", "^0.8.0"]
+  }
+}

contracts/Subscriptions.sol

@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import "@openzeppelin/contracts/utils/Counters.sol";
+import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
+import "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
+import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
+
+contract Subscriptions is Initializable, UUPSUpgradeable, OwnableUpgradeable {
+    using Counters for Counters.Counter;
+    Counters.Counter internal _subscriptionIds;
+
+    struct Subscription {
+        address contractAddress;
+        string[] topics;
+    }
+
+    mapping (address => uint256[]) public subscriptionsIdsByUser;
+    mapping (uint256 => Subscription) public subscriptionsById;
+    mapping (address => uint256) public blockNumbersByUser;
+
+    function initialize() public initializer onlyProxy {
+        __Ownable_init();
+        __UUPSUpgradeable_init();
+    }
+
+    function _authorizeUpgrade(address) internal override onlyOwner {}
+
+    function subscribe(
+        address contractAddress,
+        string[] calldata topics
+    ) public {
+        require(topics.length > 0, "Event filter should have at least 1 topic");
+        require(topics.length <= 4, "Event filter cannot have more than 4 topics");
+
+        _subscriptionIds.increment();
+        uint256 newSubscriptionId = _subscriptionIds.current();
+
+        subscriptionsIdsByUser[msg.sender].push(newSubscriptionId);
+        subscriptionsById[newSubscriptionId] = Subscription(contractAddress, topics);
+        blockNumbersByUser[msg.sender] = block.timestamp;
+    }
+
+    function unsubscribe(uint256 index) public {
+        uint256 userSubscriptionsLength = subscriptionsIdsByUser[msg.sender].length;
+
+        require(index < userSubscriptionsLength, "Non-existent subscription index");
+
+        subscriptionsIdsByUser[msg.sender][index] = subscriptionsIdsByUser[msg.sender][userSubscriptionsLength - 1];
+        subscriptionsIdsByUser[msg.sender].pop();
+    }
+
+    function updateBlockTimeStamp() public {
+        blockNumbersByUser[msg.sender] = block.timestamp;
+    }
+
+    function getSubscriptionsByUser(address userAddress)
+        public
+        view
+        returns (Subscription[] memory)
+    {
+        uint256 userSubscriptionsLength = subscriptionsIdsByUser[userAddress].length;
+
+        Subscription[] memory userSubscriptions = new Subscription[](userSubscriptionsLength);
+        for (uint i = 0; i < userSubscriptionsLength; i++) {
+            userSubscriptions[i] = subscriptionsById[subscriptionsIdsByUser[userAddress][i]];
+        }
+
+        return userSubscriptions;
+    }
+}

hardhat.config.ts

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+import dotenv from 'dotenv';
+import os from 'os';
+import path from 'path';
+import {hdkey} from 'ethereumjs-wallet';
+import {mnemonicToSeedSync} from 'bip39';
+import fs from 'fs';
+import {HardhatUserConfig} from 'hardhat/config';
+import '@openzeppelin/hardhat-upgrades';
+import './tasks/deploy';
+
+dotenv.config();
+
+let privateKey = process.env.DEPLOYER_ACCOUNT;
+
+try {
+    if (privateKey === undefined) {
+        const homedir = os.homedir();
+        const wallet = hdkey.fromMasterSeed(
+            mnemonicToSeedSync(
+                JSON.parse(fs.readFileSync(path.resolve(
+                    homedir,
+                    '.point',
+                    'keystore',
+                    'key.json'
+                ), 'utf8')).phrase
+            )
+        ).getWallet();
+        privateKey = wallet.getPrivateKey().toString('hex');
+    }
+} catch (e) {
+    if (!privateKey) {
+        console.log(
+            'Warn: Private key not found. Will not be possible to deploy.'
+        );
+    }
+}
+
+const config: HardhatUserConfig = {
+    solidity: {
+        compilers: [
+            {
+                version: '0.8.0',
+                settings: {
+                    optimizer: {
+                        enabled: true,
+                        runs: 1000
+                    }
+                }
+            },
+            {
+                version: '0.8.4',
+                settings: {
+                    optimizer: {
+                        enabled: true,
+                        runs: 1000
+                    }
+                }
+            },
+            {
+                version: '0.8.7',
+                settings: {
+                    optimizer: {
+                        enabled: true,
+                        runs: 1000
+                    }
+                }
+            }
+        ]
+    },
+    networks: {
+        xnetUranus: {
+            accounts: [privateKey!],
+            url: 'https://xnet-uranus-1.point.space/',
+            gasPrice: 7
+        },
+        mainnet: {
+            accounts: [privateKey!],
+            url: 'https://rpc-mainnet-1.point.space',
+            gasPrice: 7
+        }
+    }
+};
+
+export default config;