promise learn

tools/app/promise-learn/src/index.ts

@@ -0,0 +1,31 @@
+const mariadb = require('mariadb')
+
+let conn : mariadb.Connection
+
+mariadb.createConnection({
+        host: 'database',
+        user: 'heroes',
+        password: 'test123',
+        database: 'heroes'
+    })
+    .then(conn => {
+        conn.query("SELECT * FROM hero")
+            .then((rows) => {
+                console.log(rows)
+                return rows
+            })
+            .then((res) => {
+                console.log(res)
+                conn.end()
+            })
+            .catch(err => {
+                console.log(err)
+                conn.end()
+            })
+    })
+    .catch(err => {
+        console.log('not connected')
+    })
+
+
+