M1ke

Branch: Tech debt

Poor quality notes, by Mike

This is some notes I took during our discussion; at the start I did try to attribute names to quotes, but as it went on a) people interjected more and it was harder to give direct attribution and b) I got a few peoples' names confused early on and that messed the rest up!

We began with the question of "define technical debt" and in fact this was the only question Dave really got to ask, as our discussion progressed naturally from trying to define it to trying to identify causes.

A few early point were made:

• Measured decision, understand the interest rate. "Different kinds of debt need different kinds of remedies"

M1ke

# https://stackoverflow.com/a/28641626/518703
def decode_ddb:
    def _sprop($key): select(keys == [$key])[$key];                 # single property objects only
       ((objects | { value: _sprop("S") })                          # string (from string)
    // (objects | { value: _sprop("NULL") | null })                 # null (from boolean)
    // (objects | { value: _sprop("B") })                           # blob (from string)
    // (objects | { value: _sprop("N") | tonumber })                # number (from string)
    // (objects | { value: _sprop("BOOL") })                        # boolean (from boolean)
    // (objects | { value: _sprop("M") | map_values(decode_ddb) })  # map (from object)
    // (objects | { value: _sprop("L") | map(decode_ddb) })         # list (from encoded array)

M1ke

const apiGWEventFromReq = (req: Request): APIGatewayEvent => {
    const [headers, multiValueHeaders] = Object.keys(req.headers).reduce((parts, key) => {
        const val = req.headers[key]
        if (!val) {
            return parts
        }
        const [headers, multiValueHeaders] = parts
        if (Array.isArray(val)) {
            multiValueHeaders[key] = val;
        } else {

M1ke

<?php

const PSALM_STRING = ': string';
const SELECT_ALL = '*';
// These must be upper case to avoid accidental positives
const SQL_SELECT = 'SELECT';
const SQL_FROM = 'FROM';
const ARG_DEBUG = '--debug';
// This is lower case as the field names are forced to lower case
const SQL_AS = ' as ';

M1ke

pipelines:
  # Manually triggered Pipelines
  custom:
    composer-update:
      - step:
          name: Composer Update
          image: prooph/composer:<pick your version, e.g 7.4>
          script:
            - export COMPOSER_BRANCH="composer-update-auto-$(date +"%Y-%m-%d")"
            - git checkout -b "$COMPOSER_BRANCH"

M1ke

#!/bin/bash

# Install grip $ pip install grip
# Install wkhtmltopdf $ sudo apt-get install wkhtmltopdf

md=$1
pdf=$md.pdf
port=$(( ( RANDOM % 6000 )  + 5000 ))

echo $port

M1ke

<?php
/*
 * Declare the following consts:
 * 
 * REPO_DEFAULT - Set this to avoid having to type each time
 * TEAM - Find this in URLs
 * USER, PASS - Bitbucket credentials
 * 
 * Install Guzzle and require './vendor/autoload.php'
 */

M1ke

Using AWS RDS we can export default MySQL logs to CloudWatch. This can include the slow query log.

As standard, CloudWatch logs will just show the log message, which allows reading the log, but not doing useful analysis, such as finding the slowest queries over a time range, or the slow query which repeats the most often.

Using CloudWatch Insights we can write custom log search queries to try and extract more information. It starts with a parse step, where the "glob" parser can be used to take a single block log message and pull out individual data points:

PARSE @message '# Time: * *\n# User@Host: *[*] @ * Id: *\n# Query_time: * Lock_time: * Rows_sent: * Rows_examined: *\n*' as date,time,user,host,ip,id,duration,lock,rows,examined,query

M1ke

interface AsNumber {
	public function asNumber(): int;
}

interface CanBeAdded {
	public function add(AsNumber $b): int;
}

interface CanBeMultiplied {
	public function multiply(AsNumber $b): int;

M1ke

Felt I should collate useful stuff I constantly bounce between files to look up

Expand alias (when in interactive terminal)

Ctrl + Alt + e

(Ubuntu)

Exit if variable (e.g. envvar) isn't set