feat: update session handling and add session history endpoint

realtime/src/store/db.js

@@ -2,7 +2,7 @@ const { Pool }  = require('pg');
 
 const baseConfig = {
     user: process.env.DB_USER,
-    password: process.env.DB_PSW,
+    password: process.env.DB_PASSWORD,
     host: process.env.DB_HOST,
     port: process.env.DB_PORT,
     max: 10,
@@ -11,14 +11,19 @@ const baseConfig = {
 };
 
 const dbs = {
-    data: { name: process.env.DATA_DB },
-    sensors: { name: process.env.SENSORS_DB }
+    data: { name: process.env.DATA_DB || 'data' },
+    sensors: { name: process.env.SENSORS_DB || 'sensors' }
 }
 
+const pools = {};
+
 function getPool(db) {
     const dbConfig = dbs[db];
     if (!dbConfig) throw new Error(`Database ${db} not configured`);
-    return new Pool({ ...baseConfig, database: dbConfig.name });
+    if (!pools[db]) {
+        pools[db] = new Pool({ ...baseConfig, database: dbConfig.name });
+    }
+    return pools[db];
 }
 
 async function checkConnection(db) {
@@ -26,8 +31,8 @@ async function checkConnection(db) {
         await getPool(db).query('SELECT NOW()');
         return true;
     } catch (err) {
-        console.error(`Error connecting to ${db} database`, err);
-        return false;   
+        console.error(`Error connecting to ${db} database`, err.message);
+        return false;
     }
 }
 
@@ -38,6 +43,7 @@ async function query(db, text, params) {
 
 async function init() {
     try {
+        // Tabella sensori
         await query('sensors', `
             CREATE TABLE IF NOT EXISTS sensors (
                 id SERIAL PRIMARY KEY,
@@ -46,11 +52,28 @@ async function init() {
                 created_at TIMESTAMPTZ DEFAULT NOW()
             );
         `);
+
+        // Tabella sessioni: mappa session_id (tag InfluxDB) a metadati custom
+        await query('sensors', `
+            CREATE TABLE IF NOT EXISTS sessiondataref (
+                id SERIAL PRIMARY KEY,
+                session_id VARCHAR(32) UNIQUE NOT NULL,
+                sensor_name VARCHAR(255) NOT NULL,
+                name VARCHAR(255),
+                description TEXT,
+                tags TEXT[] DEFAULT '{}',
+                created_at TIMESTAMPTZ DEFAULT NOW(),
+                disconnected_at TIMESTAMPTZ,
+                updated_at TIMESTAMPTZ DEFAULT NOW()
+            );
+        `);
+
+        console.log('[DB] Tabelle verificate (sensors, sessiondataref)');
     } catch (err) {
-        console.error('Error creating sensors table', err);
+        console.error('[DB] Error creating tables:', err.message);
     }
 }
 
 init();
 
-module.exports = { checkConnection, query };
+module.exports = { checkConnection, query };

realtime/src/store/influx.js

@@ -15,11 +15,10 @@ const writeApi = client.getWriteApi(org, bucket, 'ms', {
 
 /**
  * Scrive dati generici su InfluxDB senza mapping.
- * I campi vengono scritti con il nome originale.
  * @param {string} measurement - nome della measurement (es. 'logs', 'weather')
  * @param {Object} fields - campi { key: value }
  * @param {string} sensor - nome del sensore
- * @param {string} session - id sessione
+ * @param {string} session - id sessione (tag immutabile)
  * @param {number} timestamp - timestamp unix ms
  */
 function writeGenericData(measurement, fields, sensor, session, timestamp) {
@@ -52,6 +51,24 @@ function writeForecastBatch(points, sensor, session) {
     }
 }
 
+/**
+ * Forza il flush del buffer di scrittura.
+ */
+async function flush() {
+    try {
+        await writeApi.flush();
+    } catch (err) {
+        console.error('[INFLUX] Flush error:', err.message);
+    }
+}
+
+/**
+ * Query storica per una sessione: ritorna righe pivotate con tutti i campi.
+ * @param {string} sensor - nome sensore
+ * @param {string} session - session_id (tag InfluxDB)
+ * @param {string} since - ISO timestamp o duration (es. "-30d")
+ * @returns {Array<Object>}
+ */
 async function queryHistory(sensor, session, since) {
     const queryApi = client.getQueryApi(org);
     const fluxQuery = `
@@ -61,6 +78,7 @@ async function queryHistory(sensor, session, since) {
             |> filter(fn: (r) => r.sensor == "${sensor}")
             |> filter(fn: (r) => r.session == "${session}")
             |> pivot(rowKey:["_time"], columnKey: ["_field"], valueColumn: "_value")
+            |> sort(columns: ["_time"])
     `;
 
     const rows = [];
@@ -75,4 +93,44 @@ async function queryHistory(sensor, session, since) {
     });
 }
 
-module.exports = { writeGenericData, writeForecastBatch, queryHistory };
+/**
+ * Esporta tutti i dati di una sessione come CSV.
+ * @param {string} sensor - nome sensore
+ * @param {string} session - session_id
+ * @param {string} since - ISO timestamp inizio (opzionale, default -30d)
+ * @returns {string} CSV content
+ */
+async function exportSessionCSV(sensor, session, since) {
+    const start = since || '-30d';
+    const rows = await queryHistory(sensor, session, start);
+
+    if (rows.length === 0) return '';
+
+    // Raccogli tutti i field names (esclusi meta InfluxDB)
+    const metaKeys = new Set(['result', 'table', '_start', '_stop', '_measurement', 'sensor', 'session', '']);
+    const fieldNames = new Set();
+    for (const row of rows) {
+        for (const key of Object.keys(row)) {
+            if (!metaKeys.has(key) && key !== '_time') {
+                fieldNames.add(key);
+            }
+        }
+    }
+
+    const fields = Array.from(fieldNames).sort();
+    const header = ['timestamp', ...fields].join(',');
+
+    const csvRows = rows.map(row => {
+        const ts = row._time || '';
+        const values = fields.map(f => {
+            const v = row[f];
+            if (v === null || v === undefined) return '';
+            return v;
+        });
+        return [ts, ...values].join(',');
+    });
+
+    return header + '\n' + csvRows.join('\n') + '\n';
+}
+
+module.exports = { writeGenericData, writeForecastBatch, flush, queryHistory, exportSessionCSV };