March 2018
Beginner to intermediate
624 pages
16h 10m
Japanese
Content preview from Head First Python 第2版 ―頭とからだで覚えるPythonの基本
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
簡単なおさらい：堅牢にする
この章の目的を思い出してみましょう。
Web
アプリケーションのコードをさらに堅牢にする
ために、起こりそうな
4
つの問題に関する疑問に答える必要がありました。それぞれの疑問をお
さらいし、どのように対応したかを示しましょう。
長い時間がかかったら？
この
11
章の冒頭
416
ページのエクササイズの中でも、「長い時間がかかったら？」という疑問
がありました。そのときは
log_request
関数と
view_the_log
関数で発生した
cursor.
execute
呼び出しの検査が原因でした。上の疑問
1
から
4
でも
log_request
と
cursor.
execute
は登場しています。まだ解決されたわけではないのです。
log_request
と
view_the_log
はどちらも、
UseDatabase
コンテキストマネージャを
使って
SQL
クエリを実行します。
log_request
関数は送信された検索の詳細をデータベース
に書き込むのに対し、
view_the_log
関数はデータベースから読み込みます。
問題は、「この書き込みや読み込みに長い時間がかかった場合にどうするか」です。
答えはプログラミング世界の多くのことと同様、その状況次第です。
1
データベース接続に失敗したら？
バックエンドデータベースが見つからないときに起こる新たな例外
ConnectionError
を作成
しました。そして、
try/except
を使って
ConnectionError
に対応します。
2
Web
アプリケーションは攻撃から守られている？ ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.