February 2019 – Page 4 – ソフトウェアエンジニアの技術ブログ：Software engineer tech blog

“tree” | useful linux command for making directory configuration diagram

If you are in development project, occasionally there are cases to make directory charts, but if you use linux “tree” command, you can make it in short.
Really?

First of all, prepare for the simple files.

[vagrant@localhost tests]$ tree -d
-bash: tree: コマンドが見つかりません

なにいいいいいいいいいいいいいいいいいいいいいいいい？
linuxでデフォルトで入ってるんちゃうんかい。。。

# sudo yum install tree

インストール:
  tree.x86_64 0:1.5.3-3.el6
完了しました!

[vagrant@localhost tests]$ tree
.
├── asset
│   ├── css
│   │   └── style.css
│   └── js
│       └── app.js
└── index.php

3 directories, 3 files

ooooooooooooooooooooooooooo, shaddy!!!!!!!!!

[vagrant@localhost tests]$ git clone https://github.com/githubix/test.git
Initialized empty Git repository in /home/vagrant/local/app/tests/test/.git/
remote: Enumerating objects: 42, done.
remote: Counting objects: 100% (42/42), done.
remote: Compressing objects: 100% (32/32), done.
remote: Total 45 (delta 4), reused 4 (delta 0), pack-reused 3
Unpacking objects: 100% (45/45), done.
[vagrant@localhost tests]$ ls
index.php  test
[vagrant@localhost tests]$ tree
.
├── index.php
└── test
    └── test.php

1 directory, 2 files

すげーーーーーーーーーーーーーーーーーー
やべーーーーーーーーー

いや、待て。markdownの書き方だ。。うむーExcelか？

Useful symbols when writing directory structure diagrams

Let’s write it for testing

root/
 ├ bin/
 ├ etc/
 ├ usr/
 |  └ local/
 |      └ bin/
 └ lib/

In conclusion, as long as there are at least the following two symbols, it does not bother me to a certain extend when writing DFL.

├
└

Somehow, I want to write in markdown form for DFL.

align right button with css

text-align does not work well

#btright{	
	text-align:right;
}

change to margin auto

#btright{
	display: block;
	margin: 0 0 0 auto;	
/*	text-align:right;*/
}

What will happen if try to put in excess data type on mysql

mysql> create table news(
    -> id int auto_increment PRIMARY KEY,
    -> content varchar(10)
    -> );
Query OK, 0 rows affected (0.25 sec)

mysql> insert into news(news) values('テスト');
ERROR 1054 (42S22): Unknown column 'news' in 'field list'
mysql> insert into news(content) values('テスト');
Query OK, 1 row affected (0.04 sec)

mysql> select * from news;
+----+-----------+
| id | content   |
+----+-----------+
|  1 | テスト    |
+----+-----------+
1 row in set (0.00 sec)

mysql> insert into news(content) values('10byte以上を入れてみたいと思う.さてどうなるでしょうか？');
Query OK, 1 row affected, 1 warning (0.10 sec)

mysql> select * from news;
+----+--------------------+
| id | content            |
+----+--------------------+
|  1 | テスト             |
|  2 | 10byte以上を入     |
+----+--------------------+
2 rows in set (0.00 sec)

If I enter an amount that exceeds data type, only the acceptable number of bytes will be in the record.

TINYTEXT, TEXT, MEDIUMTEXT, LONGTEXT

TINYTEXT
character type large object column, maximum length is 255(2^8 -1) characters.

TEXT
Character type large object column, maximum length is 65,535(2^16 – 1) characters.

MEDIUMTEXT
Character type large object column, maximum length is 16,777,215(2^24 – 1) characters.

LONGTEXT
Character large object column, maximum length is 4,294,967,295(2^32 – 1) characters.

Let’s get started.

mysql> create table news(
    -> id int,
    -> news mediumtext
    -> );
Query OK, 0 rows affected (0.54 sec)

mysql> describe news;
+-------+------------+------+-----+---------+-------+
| Field | Type       | Null | Key | Default | Extra |
+-------+------------+------+-----+---------+-------+
| id    | int(11)    | YES  |     | NULL    |       |
| news  | mediumtext | YES  |     | NULL    |       |
+-------+------------+------+-----+---------+-------+
2 rows in set (0.03 sec)

すげー、なるほど^^

Processing flow of Code Deploy

The CodeDeploy agent for each instance polls CodeDeploy to decide what to retrieve from when specified Amazon S3 bucket or GitHub repository.

The CodeDeploy agent for each instance gets the target revision from the Amazon S3 bucket or GitHub repository and uses the appspec file procedure to deploy the content to the instance.

推薦されたので、読了した。
最初、「越境」という意味が、国境を超える、と思っていたのだが、そうではなくて、一歩踏み出す、という意味だ。
本書はソフトウェア開発における悩みやその解決のアプローチ方法を多数提示している。よって、環境や立場は異なるが、各登場人物の心境に共感できることが多く、読み物として楽しめる。俯瞰して読むことで、チーム開発においては、身勝手な行動は一切慎むべきだということが手に取るようにわかる。また、突き詰めると、エンジニアや当事者のスキルセット次第ということもよくわかる。スキルが足りないと、コミュニケーションミスが齟齬が起きやすいように感じた。

Laravel log

storate/logs/laravel.log

[2018-11-17 11:22:12] local.ERROR: SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes (SQL: alter table `users` add unique `users_email_unique`(`email`)) {"exception":"[object] (Illuminate\\Database\\QueryException(code: 42000): SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes (SQL: alter table `users` add unique `users_email_unique`(`email`)) at /home/vagrant/local/zeus/vendor/laravel/framework/src/Illuminate/Database/Connection.php:664, PDOException(code: 42000): SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes at /home/vagrant/local/zeus/vendor/laravel/framework/src/Illuminate/Database/Connection.php:458)
[stacktrace]