jsl data - first line is structure

packages/api/src/controllers/jsldata.js

@@ -4,6 +4,22 @@ const lineReader = require('line-reader');
 const { jsldir } = require('../utility/directories');
 const socket = require('../utility/socket');
 
+function readFirstLine(file) {
+  return new Promise((resolve, reject) => {
+    lineReader.open(file, (err, reader) => {
+      if (err) reject(err);
+      if (reader.hasNextLine()) {
+        reader.nextLine((err, line) => {
+          if (err) reject(err);
+          resolve(line);
+        });
+      } else {
+        resolve(null);
+      }
+    });
+  });
+}
+
 module.exports = {
   openedReaders: {},
 
@@ -37,7 +53,10 @@ module.exports = {
 
   openReader(jslid) {
     // console.log('OPENING READER');
-    console.log('OPENING READER, LINES=', fs.readFileSync(path.join(jsldir(), `${jslid}.jsonl`), 'utf-8').split('\n').length);
+    console.log(
+      'OPENING READER, LINES=',
+      fs.readFileSync(path.join(jsldir(), `${jslid}.jsonl`), 'utf-8').split('\n').length
+    );
     const file = path.join(jsldir(), `${jslid}.jsonl`);
     return new Promise((resolve, reject) =>
       lineReader.open(file, (err, reader) => {
@@ -58,15 +77,18 @@ module.exports = {
     if (!this.openedReaders[jslid]) {
       await this.openReader(jslid);
     }
+    await this.readLine(jslid); // skip structure
     while (this.openedReaders[jslid].readedCount < offset) {
       await this.readLine(jslid);
     }
   },
 
   getInfo_meta: 'get',
-  getInfo({ jslid }) {
-    const file = path.join(jsldir(), `${jslid}.jsonl.info`);
-    return JSON.parse(fs.readFileSync(file, 'utf-8'));
+  async getInfo({ jslid }) {
+    const file = path.join(jsldir(), `${jslid}.jsonl`);
+    const firstLine = await readFirstLine(file);
+    if (firstLine) return JSON.parse(firstLine);
+    return null;
   },
 
   getRows_meta: 'get',

packages/api/src/proc/sessionProcess.js

@@ -17,10 +17,10 @@ class TableWriter {
   constructor(columns) {
     this.jslid = uuidv1();
     this.currentFile = path.join(jsldir(), `${this.jslid}.jsonl`);
-    this.currentStream = fs.createWriteStream(this.currentFile);
     this.currentRowCount = 0;
     this.currentChangeIndex = 0;
-    fs.writeFileSync(`${this.currentFile}.info`, JSON.stringify(columns));
+    fs.writeFileSync(this.currentFile, JSON.stringify(columns) + '\n');
+    this.currentStream = fs.createWriteStream(this.currentFile, { flags: 'a' });
     this.writeCurrentStats(false, false);
     process.send({ msgtype: 'recordset', jslid: this.jslid });
   }