我刚刚编写了一些小测试代码,如何使用 knex 跟踪事务持续时间。
https://runkit.com/embed/679qu91ylu4w
/**
* Calculate transaction durations in knex
*
*/
require('sqlite3');
var knex = require("knex")({
client: 'sqlite',
connection: ':memory:',
pool: { min: 1, max: 10 }
});
function isTransactionStart(querySpec) {
return querySpec.sql === 'BEGIN;';
}
function isTransactionEnd(querySpec) {
return querySpec.sql === 'COMMIT;' || querySpec.sql === 'ROLLBACK;';
}
const transactionDurations = {};
knex.on('query', querySpec => {
console.log('On query', querySpec);
if (isTransactionStart(querySpec)) {
if (transactionDurations[querySpec.__knexUid]) {
console.error('New transaction started, before earlier was ended');
return;
}
transactionDurations[querySpec.__knexUid] = new Date().getTime();
}
if (isTransactionEnd(querySpec)) {
const startTime = transactionDurations[querySpec.__knexUid];
if (!startTime) {
console.error('Transaction end detected, but start time not found');
}
const endTime = new Date().getTime();
transactionDurations[querySpec.__knexUid] = null;
console.log('TRANSACTION DURATION', endTime - startTime);
}
});
// just as an example of other available events to show when they are called
knex.on('query-response', (res, querySpec) => {
// console.log('On query response', res, querySpec);
});
knex.on('query-error', (err, querySpec) => {
// console.log('On query error', err, querySpec);
});
try {
a = await Promise.all([
knex.transaction(trx => {
return trx.raw('select 1');
}),
knex.transaction(trx => {
return trx.raw('select 2');
}),
knex.transaction(trx => {
return trx.raw('error me');
})
]);
} catch (e) {
console.log('Got ERROR:', e);
}
同样的方法也应该适用于查询计时。为了防止计时器簿记泄漏内存,您应该添加一些清理代码。
查询持续时间计时器应启动于query
事件并停在query-response
or query-error
取决于哪个先触发。
为了能够匹配query
- query-response
pair querySpec.__knexQueryUid
可以使用属性。