Backend/node_modules/mysql/lib/PoolNamespace.js
2021-12-31 15:03:23 +05:30

137 lines
3.1 KiB
JavaScript

var Connection = require('./Connection');
var PoolSelector = require('./PoolSelector');
module.exports = PoolNamespace;
/**
* PoolNamespace
* @constructor
* @param {PoolCluster} cluster The parent cluster for the namespace
* @param {string} pattern The selection pattern to use
* @param {string} selector The selector name to use
* @public
*/
function PoolNamespace(cluster, pattern, selector) {
this._cluster = cluster;
this._pattern = pattern;
this._selector = new PoolSelector[selector]();
}
PoolNamespace.prototype.getConnection = function(cb) {
var clusterNode = this._getClusterNode();
var cluster = this._cluster;
var namespace = this;
if (clusterNode === null) {
var err = null;
if (this._cluster._findNodeIds(this._pattern, true).length !== 0) {
err = new Error('Pool does not have online node.');
err.code = 'POOL_NONEONLINE';
} else {
err = new Error('Pool does not exist.');
err.code = 'POOL_NOEXIST';
}
cb(err);
return;
}
cluster._getConnection(clusterNode, function(err, connection) {
var retry = err && cluster._canRetry
&& cluster._findNodeIds(namespace._pattern).length !== 0;
if (retry) {
namespace.getConnection(cb);
return;
}
if (err) {
cb(err);
return;
}
cb(null, connection);
});
};
PoolNamespace.prototype.query = function (sql, values, cb) {
var cluster = this._cluster;
var clusterNode = this._getClusterNode();
var query = Connection.createQuery(sql, values, cb);
var namespace = this;
if (clusterNode === null) {
var err = null;
if (this._cluster._findNodeIds(this._pattern, true).length !== 0) {
err = new Error('Pool does not have online node.');
err.code = 'POOL_NONEONLINE';
} else {
err = new Error('Pool does not exist.');
err.code = 'POOL_NOEXIST';
}
process.nextTick(function () {
query.on('error', function () {});
query.end(err);
});
return query;
}
if (!(typeof sql === 'object' && 'typeCast' in sql)) {
query.typeCast = clusterNode.pool.config.connectionConfig.typeCast;
}
if (clusterNode.pool.config.connectionConfig.trace) {
// Long stack trace support
query._callSite = new Error();
}
cluster._getConnection(clusterNode, function (err, conn) {
var retry = err && cluster._canRetry
&& cluster._findNodeIds(namespace._pattern).length !== 0;
if (retry) {
namespace.query(query);
return;
}
if (err) {
query.on('error', function () {});
query.end(err);
return;
}
// Release connection based off event
query.once('end', function() {
conn.release();
});
conn.query(query);
});
return query;
};
PoolNamespace.prototype._getClusterNode = function _getClusterNode() {
var foundNodeIds = this._cluster._findNodeIds(this._pattern);
var nodeId;
switch (foundNodeIds.length) {
case 0:
nodeId = null;
break;
case 1:
nodeId = foundNodeIds[0];
break;
default:
nodeId = this._selector(foundNodeIds);
break;
}
return nodeId !== null
? this._cluster._getNode(nodeId)
: null;
};