worker index basic support export/import

example/nodejs-commonjs/basic-worker-export-import/config.js

@@ -0,0 +1,29 @@
+const { Encoder } = require("flexsearch");
+const fs = require("fs").promises;
+
+(async function(){
+    await fs.mkdir("./export/").catch(e => {});
+}());
+
+module.exports = {
+    tokenize: "forward",
+    encoder: new Encoder({
+        normalize: function(str){
+            return str.toLowerCase();
+        }
+    }),
+    export: async function(key, data){
+
+        await fs.writeFile("./export/" + key, data, "utf8");
+    },
+    import: async function(index){
+
+        let files = await fs.readdir("./export/");
+        files = await Promise.all(files);
+
+        for(let i = 0; i < files.length; i++){
+            const data = await fs.readFile("./export/" + files[i], "utf8");
+            index.import(files[i], data);
+        }
+    }
+};

example/nodejs-commonjs/basic-worker-export-import/index.js

@@ -0,0 +1,68 @@
+const { Worker: WorkerIndex } = require("flexsearch");
+
+(async function(){
+
+    // create a simple index which can store id-content-pairs
+    // and await (!) for the worker response
+    let index = await new WorkerIndex({
+        tokenize: "forward",
+        config: __dirname + "/config.js"
+    });
+
+    // some test data
+    const data = [
+        'cats abcd efgh ijkl mnop qrst uvwx cute',
+        'cats abcd efgh ijkl mnop qrst cute',
+        'cats abcd efgh ijkl mnop cute',
+        'cats abcd efgh ijkl cute',
+        'cats abcd efgh cute',
+        'cats abcd cute',
+        'cats cute'
+    ];
+
+    // add test data
+    data.forEach((item, id) => {
+        index.add(id, item);
+    });
+
+    // perform query
+    let result = await index.search({
+        query: "cute cat",
+    });
+
+    // display results
+    result.forEach(i => {
+        console.log(data[i]);
+    });
+
+    // -----------------------
+    // EXPORT
+    // -----------------------
+
+    await index.export(function(){
+        // do nothing here
+    });
+
+    index = await new WorkerIndex({
+        tokenize: "forward",
+        config: __dirname + "/config.js"
+    });
+
+    // -----------------------
+    // IMPORT
+    // -----------------------
+
+    await index.import();
+
+    // perform query
+    result = await index.search({
+        query: "cute cat",
+    });
+
+    // display results
+    console.log("-------------------------------------");
+    result.forEach(i => {
+        console.log(data[i]);
+    });
+
+}());

example/nodejs-commonjs/basic-worker-export-import/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "nodejs-commonjs-basic-worker-extern-config",
+  "dependencies": {
+    "flexsearch": "^0.8.105"
+  }
+}