From 9b82911aa8635aa0b9150d357f25a6b1e2f7f388 Mon Sep 17 00:00:00 2001
From: GuillaumeRenouvin <guillaumer@theodo.fr>
Date: Wed, 8 Aug 2018 16:17:22 +0200
Subject: [PATCH 1/2] [MO] How to log your queries duration with Knex

---
 SUMMARY.MD                                    |  1 +
 .../log-queries-durations-with-knex.mo.md     | 60 +++++++++++++++++++
 2 files changed, 61 insertions(+)
 create mode 100644 performance/backend/log-queries-durations-with-knex.mo.md

diff --git a/SUMMARY.MD b/SUMMARY.MD
index e9d1d08..090dae2 100644
--- a/SUMMARY.MD
+++ b/SUMMARY.MD
@@ -118,6 +118,7 @@
       - [1. Cache your routes using varnish](/performance/backend/cache-routes-using-varnish.mo.md)
       - [2. Serve images as static files](/performance/backend/serve-images-as-static-files.mo)
       - [3. Minimize your number of SQL queries](/performance/backend/minimize-number-sql-queries.mo.md)
+      - [4. Log queries durations with Knex](/performance/backend/log-queries-durations-with-knex.mo.md)
     - Front
       - 1.  Pure components **-> [To do]**
   - Have you a mean of keeping the performance under control?
diff --git a/performance/backend/log-queries-durations-with-knex.mo.md b/performance/backend/log-queries-durations-with-knex.mo.md
new file mode 100644
index 0000000..bed921a
--- /dev/null
+++ b/performance/backend/log-queries-durations-with-knex.mo.md
@@ -0,0 +1,60 @@
+# [MO] How to log your queries durations with Knex (~10)
+
+## Owner: [Guillaume Renouvin](https://github.com/GuillaumeRenouvin)
+## Creation date: August, 1st 2018
+## Update date: August, 1st 2018
+
+## Context
+- You want to log your database requests durations using Knex query builder
+
+## Prerequisites
+- Have Knex installed
+
+## Steps
+
+### Log your queries informations (~5min)
+- After your Knex instantiation add listeners on each query, query response and query errors
+```javascript
+db.on('query', query => {
+ console.log(query.sql);
+})
+ .on('query-response', (response, query) => {
+   console.log(query.sql);
+ })
+ .on('query-error', err => {
+   console.log(err);
+ });
+```
+> Check: Launch your server, call an API route and you should see your queries on the logs
+
+### Log query duration (~5min)
+- Blabla
+  ```javascript
+import now from 'performance-now';
+
+const durations = {};
+
+knex
+ .on('query', query => {
+   times[uid] = {
+     query,
+     startTime: now(),
+   };
+ })
+ .on('query-response', (response, query) => {
+   times[query.__knexQueryUid].endTime = now();
+
+   console.log(query.sql, ',', `[${query.bindings ? query.bindings.join(',') : ''}]`);
+   console.log(
+     `Time: ${(
+       times[query.__knexQueryUid].endTime - times[query.__knexQueryUid].startTime
+     ).toFixed(3)} ms\n`
+   );
+   delete times[uid];
+ });
+
+  ```
+> Check: Launch your server, call an API route and you should see your queries durations on the logs
+
+### Sources
+- [Timing Your Queries in Knex.js for Node.js](https://spin.atomicobject.com/2017/03/27/timing-queries-knexjs-nodejs/)

From 223801d0da406d05488c741b30f3c2c3d75e6930 Mon Sep 17 00:00:00 2001
From: GuillaumeRenouvin <guillaumer@theodo.fr>
Date: Fri, 17 Aug 2018 10:26:45 +0200
Subject: [PATCH 2/2] fix scripts and remove blabla

---
 .../backend/log-queries-durations-with-knex.mo.md  | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/performance/backend/log-queries-durations-with-knex.mo.md b/performance/backend/log-queries-durations-with-knex.mo.md
index bed921a..733d9a5 100644
--- a/performance/backend/log-queries-durations-with-knex.mo.md
+++ b/performance/backend/log-queries-durations-with-knex.mo.md
@@ -16,7 +16,7 @@
 - After your Knex instantiation add listeners on each query, query response and query errors
 ```javascript
 db.on('query', query => {
- console.log(query.sql);
+  console.log(query.sql);
 })
  .on('query-response', (response, query) => {
    console.log(query.sql);
@@ -28,29 +28,29 @@ db.on('query', query => {
 > Check: Launch your server, call an API route and you should see your queries on the logs
 
 ### Log query duration (~5min)
-- Blabla
-  ```javascript
+
+```javascript
 import now from 'performance-now';
 
 const durations = {};
 
 knex
  .on('query', query => {
-   times[uid] = {
+   durations[query.__knexQueryUid] = {
      query,
      startTime: now(),
    };
  })
  .on('query-response', (response, query) => {
-   times[query.__knexQueryUid].endTime = now();
+   durations[query.__knexQueryUid].endTime = now();
 
    console.log(query.sql, ',', `[${query.bindings ? query.bindings.join(',') : ''}]`);
    console.log(
      `Time: ${(
-       times[query.__knexQueryUid].endTime - times[query.__knexQueryUid].startTime
+       durations[query.__knexQueryUid].endTime - durations[query.__knexQueryUid].startTime
      ).toFixed(3)} ms\n`
    );
-   delete times[uid];
+   delete durations[uid];
  });
 
   ```