src, doc, test: allow passing name of database to createSession

Author: louwers

doc/api/sqlite.md

@@ -158,6 +158,7 @@ around [`sqlite3_prepare_v2()`][].
 * `options` {Object} An optional object used to configure the session.
   * `table` {string} When provided, only changes to this table are tracked by the created session.
     By default, changes to all tables are tracked.
+  * `db` {string} Name of the database. Default: `'main'`.
 * Returns: {Session} A session handle.
 
 Creates and attackes a session to the database. This method is a wrapper around [`sqlite3session_create()`][] and [`sqlite3session_attach()`][].

src/node_sqlite.cc

@@ -224,6 +224,7 @@ void DatabaseSync::Exec(const FunctionCallbackInfo<Value>& args) {
 
 void DatabaseSync::CreateSession(const FunctionCallbackInfo<Value>& args) {
   std::string table;
+  std::string dbName = "main";
 
   Environment* env = Environment::GetCurrent(args);
   if (args.Length() > 0) {
@@ -253,16 +254,33 @@ void DatabaseSync::CreateSession(const FunctionCallbackInfo<Value>& args) {
         return;
       }
     }
+
+    Local<String> db_key = String::NewFromUtf8(
+      env->isolate(),
+      "db",
+      v8::NewStringType::kNormal).ToLocalChecked();
+    if (options->HasOwnProperty(env->context(), db_key).FromJust()) {
+      Local<Value> db_value = options->Get(
+        env->context(),
+        db_key).ToLocalChecked();
+      if (db_value->IsString()) {
+        String::Utf8Value str(env->isolate(), db_value);
+        dbName = std::string(*str);
+      } else {
+        node::THROW_ERR_INVALID_ARG_TYPE(
+            env->isolate(), "The \"options.db\" argument must be a string.");
+        return;
+      }
+    }
   }
 
   DatabaseSync* db;
   ASSIGN_OR_RETURN_UNWRAP(&db, args.This());
   THROW_AND_RETURN_ON_BAD_STATE(
       env, db->connection_ == nullptr, "database is not open");
 
-  const char* zDb = "main";  // TODO(louwers): take parameter
   sqlite3_session* pSession;
-  int r = sqlite3session_create(db->connection_, zDb, &pSession);
+  int r = sqlite3session_create(db->connection_, dbName.c_str(), &pSession);
   CHECK_ERROR_OR_THROW(env->isolate(), db->connection_, r, SQLITE_OK, void());
   db->sessions_.insert(pSession);
 

test/parallel/test-sqlite.js

@@ -901,8 +901,8 @@ suite('session extension', () => {
     return {
       database2,
       changeset: session.changeset()
-    }
-  }
+    };
+  };
 
   test('conflict while applying changeset (default abort)', (t) => {
     const { database2, changeset } = prepareConflict();
@@ -934,7 +934,7 @@ suite('session extension', () => {
     t.assert.strictEqual(result, true);
     t.assert.deepStrictEqual(
       database2.prepare('SELECT value from data ORDER BY key').all(),
-      [{ value: 'hello'}, { value: 'foo' }]);  // replaced
+      [{ value: 'hello' }, { value: 'foo' }]);  // replaced
   });
 
   test('conflict while applying changeset (omit)', (t) => {
@@ -946,7 +946,7 @@ suite('session extension', () => {
     t.assert.strictEqual(result, true);
     t.assert.deepStrictEqual(
       database2.prepare('SELECT value from data ORDER BY key ASC').all(),
-      [{ value: 'world'}, { value: 'foo' }]);  // conflicting change omitted
+      [{ value: 'world' }, { value: 'foo' }]);  // Conflicting change omitted
   });
 
   test('constants are defined', (t) => {
@@ -979,4 +979,21 @@ suite('session extension', () => {
     // Expect 5 rows since these changes where not filtered out
     t.assert.strictEqual(data2Rows.length, 5);
   });
+
+  test('specify other database', (t) => {
+    const database = new DatabaseSync(':memory:');
+    const session = database.createSession();
+    const sessionMain = database.createSession({
+      db: 'main'
+    });
+    const sessionTest = database.createSession({
+      db: 'test'
+    });
+    database.exec('CREATE TABLE data (key INTEGER PRIMARY KEY)');
+    database.exec('INSERT INTO data (key) VALUES (1)');
+    t.assert.notStrictEqual(session.changeset().length, 0);
+    t.assert.notStrictEqual(sessionMain.changeset().length, 0);
+    // Since this session is attached to a different database, its changeset should be empty
+    t.assert.strictEqual(sessionTest.changeset().length, 0);
+  });
 });