[CONJS-24] new option "sessionVariables" to permit setting session va…

…riable at connection

documentation/connection-options.md

@@ -319,6 +319,8 @@ mariadb.createConnection({
 | **connectAttributes** | Sends information, (client name, version, operating system, Node.js version, and so on) to the [Performance Schema](https://mariadb.com/kb/en/library/performance-schema-session_connect_attrs-table/). When enabled, the Connector sends JSON attributes in addition to the defaults.  |*boolean/json* |false|
 | **metaAsArray** | Compatibility option, causes Promise to return an array object, `[rows, metadata]` rather than the rows as JSON objects with a `meta` property. |*boolean* |false|
 | **permitSetMultiParamEntries** | Compatibility option to permit setting multiple value by a JSON object to replace one question mark. key values will replace the question mark with format like `key1`=val,`key2`='val2'. Since it doesn't respect the usual prepared statement format that one value is for one question mark, this can lead to incomprehension, even if badly use to possible injection.|*boolean* |false|
+| **sessionVariables** | Permit to set session variables when connecting. Example: sessionVariables:{'idle_transaction_timeout':10000}|*json* |
+
 
 ## F.A.Q.
 

lib/config/connection-options.js

@@ -50,6 +50,7 @@ class ConnectionOptions {
     }
     this.port = opts.port || 3306;
     this.socketPath = opts.socketPath;
+    this.sessionVariables = opts.sessionVariables;
     this.supportBigNumbers = opts.supportBigNumbers || false;
     this.timezone = opts.timezone || "local";
     if (this.timezone !== "local") {

lib/connection.js

@@ -510,6 +510,45 @@ function Connection(options) {
     _initSocket(_authFail);
   };
 
+  const _addSessionVariableQuery = () => {
+    if (opts.sessionVariables) {
+      let sessionQuery = "set ";
+      let keys = Object.keys(opts.sessionVariables);
+      if (keys.length > 0) {
+        for (let k = 0; k < keys.length; ++k) {
+          sessionQuery +=
+            (k != 0 ? "," : "") +
+            "@" +
+            keys[k].replace(/[^a-z0-9_]/gi, "") +
+            "=" +
+            opts.sessionVariables[keys[k]];
+        }
+        const conn = this;
+        const errorHandling = initialErr => {
+          conn.emit(
+            "error",
+            Errors.createError(
+              "Error setting session variable (value " +
+                JSON.stringify(opts.sessionVariables) +
+                "). Error: " +
+                initialErr.message,
+              true,
+              info,
+              "08S01",
+              Errors.ER_SETTING_SESSION_ERROR,
+              null
+            )
+          );
+          conn.end().catch(err => {});
+        };
+
+        const cmd = new Query(() => {}, errorHandling, null, sessionQuery, null);
+        if (opts.trace) Error.captureStackTrace(cmd);
+        _addCommand(cmd);
+      }
+    }
+  };
+
   const _getSocket = () => {
     return _socket;
   };
@@ -574,6 +613,7 @@ function Connection(options) {
     }
 
     if (opts.pipelining) _addCommand = _addCommandEnablePipeline;
+    _addSessionVariableQuery();
     process.nextTick(resolve, this);
     _status = Status.CONNECTED;
   };

lib/misc/errors.js

@@ -86,6 +86,7 @@ module.exports.ER_AUTHENTICATION_PLUGIN_NOT_SUPPORTED = 45025;
 module.exports.ER_SOCKET_TIMEOUT = 45026;
 module.exports.ER_POOL_ALREADY_CLOSED = 45027;
 module.exports.ER_GET_CONNECTION_TIMEOUT = 45028;
+module.exports.ER_SETTING_SESSION_ERROR = 45029;
 
 const keys = Object.keys(module.exports);
 const errByNo = {};

test/integration/test-session-variables.js

@@ -0,0 +1,71 @@
+"use strict";
+
+const base = require("../base.js");
+const { assert } = require("chai");
+
+describe("session variables", () => {
+  it("with empty session variables", function(done) {
+    base
+      .createConnection({ sessionVariables: {} })
+      .then(conn => {
+        conn
+          .query("SELECT 1")
+          .then(rows => {
+            assert.deepEqual(rows, [{ "1": 1 }]);
+            conn.end();
+            done();
+          })
+          .catch(done);
+      })
+      .catch(done);
+  });
+
+  it("with one session variables", function(done) {
+    base
+      .createConnection({ sessionVariables: { wait_timeout: 10000 } })
+      .then(conn => {
+        conn
+          .query("SELECT @wait_timeout")
+          .then(rows => {
+            assert.deepEqual(rows, [{ "@wait_timeout": 10000 }]);
+            conn.end();
+            done();
+          })
+          .catch(done);
+      })
+      .catch(done);
+  });
+
+  it("with multiple session variables", function(done) {
+    base
+      .createConnection({
+        sessionVariables: { wait_timeout: 10000, interactive_timeout: 2540 },
+        debug: true
+      })
+      .then(conn => {
+        conn
+          .query("SELECT @wait_timeout, @interactive_timeout")
+          .then(rows => {
+            assert.deepEqual(rows, [{ "@wait_timeout": 10000, "@interactive_timeout": 2540 }]);
+            conn.end();
+            done();
+          })
+          .catch(done);
+      })
+      .catch(done);
+  });
+
+  it("error handling", function(done) {
+    base
+      .createConnection({ sessionVariables: { wait_timeout: "String value" }, debug: true })
+      .then(conn => {
+        conn.on("error", err => {
+          assert(err.message.includes("Error setting session variable"));
+          assert.equal(err.sqlState, "08S01");
+          assert.equal(err.code, "ER_SETTING_SESSION_ERROR");
+          done();
+        });
+      })
+      .catch(done);
+  });
+});

test/unit/io/test-packet.js

@@ -47,5 +47,4 @@ describe("packet", () => {
 
     assert.equal(packet.pos, 534);
   });
-
 });