fix: use base node14 tsconfig

[SimenB]

Since this module only supports node 14 and up we can update its target config. E.g. stop transpiling async functions and generators.

This is the diff:

diff --git i/lib/index.js w/lib/index.js
index 11bde1c..3b99547 100644
--- i/lib/index.js
+++ w/lib/index.js
@@ -1,10 +1,13 @@
 "use strict";
-exports.__esModule = true;
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
+};
+Object.defineProperty(exports, "__esModule", { value: true });
 exports.FastifySSEPlugin = void 0;
-var fastify_plugin_1 = require("fastify-plugin");
-var plugin_1 = require("./plugin");
-exports.FastifySSEPlugin = (0, fastify_plugin_1["default"])(plugin_1.plugin, {
+const fastify_plugin_1 = __importDefault(require("fastify-plugin"));
+const plugin_1 = require("./plugin");
+exports.FastifySSEPlugin = (0, fastify_plugin_1.default)(plugin_1.plugin, {
     name: "fastify-sse-v2",
-    fastify: ">=3"
+    fastify: ">=3",
 });
-exports["default"] = exports.FastifySSEPlugin;
+exports.default = exports.FastifySSEPlugin;
diff --git i/lib/plugin.js w/lib/plugin.js
index b0bce04..6579342 100644
--- i/lib/plugin.js
+++ w/lib/plugin.js
@@ -1,79 +1,39 @@
 "use strict";
-var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
-    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
-    return new (P || (P = Promise))(function (resolve, reject) {
-        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
-        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
-        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
-        step((generator = generator.apply(thisArg, _arguments || [])).next());
-    });
-};
-var __generator = (this && this.__generator) || function (thisArg, body) {
-    var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
-    return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
-    function verb(n) { return function (v) { return step([n, v]); }; }
-    function step(op) {
-        if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
-            if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
-            if (y = 0, t) op = [op[0] & 2, t.value];
-            switch (op[0]) {
-                case 0: case 1: t = op; break;
-                case 4: _.label++; return { value: op[1], done: false };
-                case 5: _.label++; y = op[1]; op = [0]; continue;
-                case 7: op = _.ops.pop(); _.trys.pop(); continue;
-                default:
-                    if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
-                    if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
-                    if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
-                    if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
-                    if (t[2]) _.ops.pop();
-                    _.trys.pop(); continue;
-            }
-            op = body.call(thisArg, _);
-        } catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
-        if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
-    }
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
 };
-exports.__esModule = true;
+Object.defineProperty(exports, "__esModule", { value: true });
 exports.plugin = void 0;
-var it_to_stream_1 = require("it-to-stream");
-var it_pushable_1 = require("it-pushable");
-var sse_1 = require("./sse");
-var util_1 = require("./util");
+const it_to_stream_1 = __importDefault(require("it-to-stream"));
+const it_pushable_1 = __importDefault(require("it-pushable"));
+const sse_1 = require("./sse");
+const util_1 = require("./util");
 // eslint-disable-next-line @typescript-eslint/require-await
-var plugin = function (instance, options) {
-    return __awaiter(this, void 0, void 0, function () {
-        return __generator(this, function (_a) {
-            instance.decorateReply("sse", function (source) {
-                var _this = this;
-                //if this already set, it's not first event
-                if (!this.raw.headersSent) {
-                    this.sseContext = { source: (0, it_pushable_1["default"])() };
-                    Object.entries(this.getHeaders()).forEach(function (_a) {
-                        var key = _a[0], value = _a[1];
-                        _this.raw.setHeader(key, value !== null && value !== void 0 ? value : "");
-                    });
-                    this.raw.setHeader("Content-Type", "text/event-stream");
-                    this.raw.setHeader("Connection", "keep-alive");
-                    this.raw.setHeader("Cache-Control", "no-cache,no-transform");
-                    this.raw.setHeader("x-no-compression", 1);
-                    this.raw.write((0, sse_1.serializeSSEEvent)({ retry: options.retryDelay || 3000 }));
-                    handleAsyncIterable(this, this.sseContext.source);
-                }
-                if ((0, util_1.isAsyncIterable)(source)) {
-                    return handleAsyncIterable(this, source);
-                }
-                else {
-                    this.sseContext.source.push(source);
-                    return;
-                }
+const plugin = async function (instance, options) {
+    instance.decorateReply("sse", function (source) {
+        //if this already set, it's not first event
+        if (!this.raw.headersSent) {
+            this.sseContext = { source: (0, it_pushable_1.default)() };
+            Object.entries(this.getHeaders()).forEach(([key, value]) => {
+                this.raw.setHeader(key, value ?? "");
             });
-            return [2 /*return*/];
-        });
+            this.raw.setHeader("Content-Type", "text/event-stream");
+            this.raw.setHeader("Connection", "keep-alive");
+            this.raw.setHeader("Cache-Control", "no-cache,no-transform");
+            this.raw.setHeader("x-no-compression", 1);
+            this.raw.write((0, sse_1.serializeSSEEvent)({ retry: options.retryDelay || 3000 }));
+            handleAsyncIterable(this, this.sseContext.source);
+        }
+        if ((0, util_1.isAsyncIterable)(source)) {
+            return handleAsyncIterable(this, source);
+        }
+        else {
+            this.sseContext.source.push(source);
+            return;
+        }
     });
 };
 exports.plugin = plugin;
 function handleAsyncIterable(reply, source) {
-    (0, it_to_stream_1["default"])((0, sse_1.transformAsyncIterable)(source)).pipe(reply.raw);
+    (0, it_to_stream_1.default)((0, sse_1.transformAsyncIterable)(source)).pipe(reply.raw);
 }
diff --git i/lib/sse.js w/lib/sse.js
index e9b18e8..de0cbcc 100644
--- i/lib/sse.js
+++ w/lib/sse.js
@@ -1,112 +1,26 @@
 "use strict";
-var __generator = (this && this.__generator) || function (thisArg, body) {
-    var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
-    return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
-    function verb(n) { return function (v) { return step([n, v]); }; }
-    function step(op) {
-        if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
-            if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
-            if (y = 0, t) op = [op[0] & 2, t.value];
-            switch (op[0]) {
-                case 0: case 1: t = op; break;
-                case 4: _.label++; return { value: op[1], done: false };
-                case 5: _.label++; y = op[1]; op = [0]; continue;
-                case 7: op = _.ops.pop(); _.trys.pop(); continue;
-                default:
-                    if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
-                    if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
-                    if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
-                    if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
-                    if (t[2]) _.ops.pop();
-                    _.trys.pop(); continue;
-            }
-            op = body.call(thisArg, _);
-        } catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
-        if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
-    }
-};
-var __asyncValues = (this && this.__asyncValues) || function (o) {
-    if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
-    var m = o[Symbol.asyncIterator], i;
-    return m ? m.call(o) : (o = typeof __values === "function" ? __values(o) : o[Symbol.iterator](), i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i);
-    function verb(n) { i[n] = o[n] && function (v) { return new Promise(function (resolve, reject) { v = o[n](v), settle(resolve, reject, v.done, v.value); }); }; }
-    function settle(resolve, reject, d, v) { Promise.resolve(v).then(function(v) { resolve({ value: v, done: d }); }, reject); }
-};
-var __await = (this && this.__await) || function (v) { return this instanceof __await ? (this.v = v, this) : new __await(v); }
-var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
-    if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
-    var g = generator.apply(thisArg, _arguments || []), i, q = [];
-    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
-    function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
-    function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
-    function fulfill(value) { resume("next", value); }
-    function reject(value) { resume("throw", value); }
-    function settle(f, v) { if (f(v), q.shift(), q.length) resume(q[0][0], q[0][1]); }
-};
-exports.__esModule = true;
+Object.defineProperty(exports, "__esModule", { value: true });
 exports.serializeSSEEvent = exports.transformAsyncIterable = void 0;
-function transformAsyncIterable(source) {
-    return __asyncGenerator(this, arguments, function transformAsyncIterable_1() {
-        var source_1, source_1_1, message, e_1_1;
-        var e_1, _a;
-        return __generator(this, function (_b) {
-            switch (_b.label) {
-                case 0:
-                    _b.trys.push([0, 7, 8, 13]);
-                    source_1 = __asyncValues(source);
-                    _b.label = 1;
-                case 1: return [4 /*yield*/, __await(source_1.next())];
-                case 2:
-                    if (!(source_1_1 = _b.sent(), !source_1_1.done)) return [3 /*break*/, 6];
-                    message = source_1_1.value;
-                    return [4 /*yield*/, __await(serializeSSEEvent(message))];
-                case 3: return [4 /*yield*/, _b.sent()];
-                case 4:
-                    _b.sent();
-                    _b.label = 5;
-                case 5: return [3 /*break*/, 1];
-                case 6: return [3 /*break*/, 13];
-                case 7:
-                    e_1_1 = _b.sent();
-                    e_1 = { error: e_1_1 };
-                    return [3 /*break*/, 13];
-                case 8:
-                    _b.trys.push([8, , 11, 12]);
-                    if (!(source_1_1 && !source_1_1.done && (_a = source_1["return"]))) return [3 /*break*/, 10];
-                    return [4 /*yield*/, __await(_a.call(source_1))];
-                case 9:
-                    _b.sent();
-                    _b.label = 10;
-                case 10: return [3 /*break*/, 12];
-                case 11:
-                    if (e_1) throw e_1.error;
-                    return [7 /*endfinally*/];
-                case 12: return [7 /*endfinally*/];
-                case 13: return [4 /*yield*/, __await(serializeSSEEvent({ event: "end", data: "Stream closed" }))];
-                case 14: return [4 /*yield*/, _b.sent()];
-                case 15:
-                    _b.sent();
-                    return [2 /*return*/];
-            }
-        });
-    });
+async function* transformAsyncIterable(source) {
+    for await (const message of source) {
+        yield serializeSSEEvent(message);
+    }
+    yield serializeSSEEvent({ event: "end", data: "Stream closed" });
 }
 exports.transformAsyncIterable = transformAsyncIterable;
 function serializeSSEEvent(chunk) {
-    var payload = "";
+    let payload = "";
     if (chunk.id) {
-        payload += "id: ".concat(chunk.id, "\n");
+        payload += `id: ${chunk.id}\n`;
     }
     if (chunk.event) {
-        payload += "event: ".concat(chunk.event, "\n");
+        payload += `event: ${chunk.event}\n`;
     }
     if (chunk.data) {
-        payload += "data: ".concat(chunk.data, "\n");
+        payload += `data: ${chunk.data}\n`;
     }
     if (chunk.retry) {
-        payload += "retry: ".concat(chunk.retry, "\n");
+        payload += `retry: ${chunk.retry}\n`;
     }
     if (!payload) {
         return "";
diff --git i/lib/types.js w/lib/types.js
index 0e34578..c8ad2e5 100644
--- i/lib/types.js
+++ w/lib/types.js
@@ -1,2 +1,2 @@
 "use strict";
-exports.__esModule = true;
+Object.defineProperty(exports, "__esModule", { value: true });
diff --git i/lib/util.js w/lib/util.js
index df6ee4d..34baadd 100644
--- i/lib/util.js
+++ w/lib/util.js
@@ -1,5 +1,5 @@
 "use strict";
-exports.__esModule = true;
+Object.defineProperty(exports, "__esModule", { value: true });
 exports.isAsyncIterable = void 0;
 function isAsyncIterable(source) {
     if (source === null || source === undefined || typeof source !== "object") {

[SimenB]

all the removed lines are defaults in @tsconfig/node14

[mpetrunic]

@SimenB Thanks for PR, since node14 is no longer maintained, could you update this to node16?