Writing idiomatic python 3
Recomended http://downloads.niceware.com/TECH-pdf/PythonStyle-Writing_idiomatic_python_3.pdf?fbclid=IwAR1uhD-_8WRmWy1Sb2Ncz9Afwk248-o5JA...
Time complexity and space complexity
時間複雜度跟空間複雜度 ## 時間複雜度 常見的六種時間複雜度與演算法 * O(1)：陣列讀取 * O(n)：簡易搜尋 * O(log n)：二分搜尋 * O(nlogn)：合併排序 * O(n²)：選擇排序 * O(2^n)：費波那契數列 時間複雜度為 O(n) ...
Start using Stripe's PaymentIntent instead of Charge to fit SCA
Since a new rule coming into effect on September 14, 2019, as part of PSD2 regulation in Europe, any integrations using the Charges API w...
Rails ActiveModel with type casting
## Basic usage Use `include ActiveModel::Model` and `include ActiveModel::Attributes` can provide type casting for active model. Exampl...
Precision and Scale in database
位數 (Precision) 是指數字中總共的位數。 小數位數 (Scale) 則是指數字中小數點右方的位數。 例如 123.45 的位數是 5，小數位數是 2。 precision 又稱精度 https://docs.microsoft.com/zh-tw/sql/...
How to test ActionMailer with RSpec
This blog post will demostrate how to test ActionMailer in Rails using RSpec. ## Configuration ```rb # config/environments/test.rb # T...
Rails lock! and with_lock
Basically, `ActiveRecord::Locking::Pessimistic#with_lock` will yield your code inside transaction but `ActiveRecord::Locking::Pessimistic...
How to test Stripe webhook's singature with Rspec
This post shows how to test Stripe webhook's singature ```rb # spec/support/stripe_test_helper.rb module StripeTestHelper def stripe_...
How to split rails routes.rb into smaller files - Extend
I've tried many ways to split `config/routes.rb` file, I find this approach is best to me because it requires no futher config to let dev...
How to split rails routes.rb into smaller files - require
Anothr approach: use `require` In `config/routes.rb` ```rb Rails.application.routes.draw do root to: "home#index" get "/about get...
How to split rails routes.rb into smaller files - instance_eval
The most common (base on my google search) way to split `config/routes.rb` in rails is by defining your own `draw` DSL. This is just one ...
Order By NULL 時的情形
Default 值： | NULL Ordering Behavior/ Database Types | MARIADB/MYSQL | SQLSERVER | HSQLDB | DB2 | ORACLE | POSTGRESQL | | --- | --- | ---...
Scaling the monolith
在拆成潮潮的 Micro Service 或是超級大 Refactor 甚至是討論要不要換語言換框架前，先從小的改變做起吧。文章列了一些滿基本但是都很實用的原則、方法、工具，下次沒票可以做或是上班閒閒時都可以試一下，還可以增進一下未來工作效率。 ~~除非你只是想要潮？（威...
儲存 sensitive 資料的一些基本作法
### 大原則： 1. sensitive 資料加密儲存 2. Web server 只放加密用的金鑰，不放可以解密的金鑰 實際做起來就是：把需要解密的金鑰放到 worker 的 server，worker server 不接受來自外面的流量、且只能透過公司的 VP...
在 Rails 裡擴充 gem 提供的 ActiveRecord model 的方法
需求：想要為 Gem 提供的 Model 增加一些新的 method 或是 association For example, doorkeeper 的 gem 有一個 `Doorkeeper::AccessToken` 的 model，我想要有個 `Doorkeeper:...
Ruby 2.6 的 Range 可以 accept nil 當作 Float::INFINITY
### Before 2.6 (v < 2.5) ```rb end_of_range = nil (1..end_of_range).map { |i| do_something(i) } #=> ArgumentError (bad value for rang...
Golang assignment (=) vs short variable declaration (:=) vs regular variable declaration (var)
## assignment 跟 declaration 差在哪？ https://stackoverflow.com/questions/23227486/difference-between-declaration-statement-and-assignment-st...
What is PKCE (Proof Key for Code Exchange)
## PKCE 什麼時候適用： 只有手機 App 沒有 Server 的時候 ## Why PKCE？ Oauth2 提供很多種 Grant Type https://oauth.net/2/grant-types/ ，就是提供很多種拿到 Token 的方法，最常看...
Basic Auth 裡的 Realm 是什麼意思？
According to the RFC 7235, the realm parameter is reserved for defining protection spaces (set of pages or resources where credentials ar...
Mac: add ssh key to ssh-agent
```sh $ ssh-add -K ~/.ssh/id_rsa ``` https://help.github.com/en/articles/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent
Rails 直接取得欄位的值（before_type_cast）
How to get column value from ActiveRecord without being affect by overrided attributes? 有時候會想要直接取得 database 裡的值，以免被 model 裡覆蓋的 attribute...
Function Composition in Ruby
Ruby 2.6 introduced `<<` and `>>` methods, this article explains function composition and history of Ruby new methods throughoutly, wort...
How to test with Salesforce Heroku Connect
## What is Heroku Connect? This is a tool provided by Salesforce and Heroku, it will automatically sync all your salesforce tables int...