【python】使用flask制作小型页面的关键点总结

目录结构

app.py                          web代码
store.db                        存储信息的轻量数据库,用的sqlite3
schema.sql                   数据库的初始化建表语句
settings.cfg                   配置信息
static/style.css              html中每个标签相关的格式信息,比如,字体颜色,字体大小,背景颜色,占用宽度高度等
templates/layout.html   目录名必须是templates。显示的web页面,使用jinja2渲染引擎,支持一些判断循环的语句  

css

一个style.css的例子

body            { font-family: sans-serif; background: #eee; }         /* 设定body模块的字体和背景颜色 */
h1, h2          { color: #377BA8; }                                                 /* 设定h1, h2的文字颜色 */
h2                { font-size: 2.5em; }                                                /* 设定h2的字体大小为默认大小的2.5倍 */
.left              {float: left; width: 50%}                                            /* 设定class为left的部分靠左侧,占用50%的宽度 */
.right            {float: right; width: 50%}                                          /* 设定class为right的部分靠右侧,占用50%的宽度 */
.comment    {width:95%; overflow:auto; word-break:break-all;}  /* 设定class为comment的部分占95%的宽度 */

templates

{% xxx %}这样的语句是jinja2的控制语句

layout.html

<!doctype html>
<title>Test</title>
<link rel=stylesheet type=text/css href="{{ url_for('static', filename='style.css') }}">    //加载css格式文件
<h1>Test</h1>
{% for message in get_flashed_messages() %}
  <div class=flash>{{ message }}</div>
{% endfor %}
{% block body %}{% endblock %}

show.html

{% extends "layout.html" %}
{% block body %}    // 新块开始,此处body对应style.css的body
<div class="left">     // 一个新区域,采用style.css中left的格式
  <form action="{{ url_for('test') }}" method=post class=test>      //提交表单区域
    <p>Text:</p>

          {% for entry in entries %}
            <textarea class=comment name=text rows=50 cols=120>{{ entry.text }}</textarea>    // 实际填写提交信息的地方
          {% else %}
            <textarea class=comment name=text rows=50 cols=120></textarea>
          {% endfor %}
      <input type=submit value=Submit>  // 表单提交按钮
  </form>
</div>
<div class="right">
  <p>Detail:</p>
  {% for entry in entries %}
    <textarea class=comment rows=50 cols=120>{{ entry.detail_str }}</textarea>
  {% else %}
    <textarea class=comment rows=50 cols=120></textarea>
  {% endfor %}
</div>
<div class="bottom">
  {% for entry in entries %}
    <h2>{{ entry.result }}</h2>
  {% endfor %}
</div>
{% endblock %}

app.py

注意数据库的获取,全局信息的处理。

    """Connects to the specific database."""
import os
import sqlite3
import urllib
import logging
import logging.handlers
import json
from datetime import datetime
from core.analysis import analysis_string_v3
from flask import Flask, request, g, redirect, url_for, render_template

app = Flask(__name__)
app.config.from_envvar('SETTINGS', silent=True)
cur_path = os.path.dirname(os.path.realpath(__file__))


def init_logging(filename, logmod):
    log_size = 100000000
    log_backupcount = 1

    handler = logging.handlers.RotatingFileHandler(filename, maxBytes=log_size, backupCount=log_backupcount)
    formatter = logging.Formatter("%(asctime)s %(levelname)s: %(message)s", datefmt='[%b %d %H:%M:%S]')
    handler.setFormatter(formatter)
    my_logger = logging.getLogger(logmod)
    my_logger.setLevel(logging.DEBUG)
    my_logger.addHandler(handler)
    return my_logger


logger = init_logging(os.path.join(cur_path, "api.log"), "test")


def connect_db():
    """Connects to the specific database."""
    logger.debug("[start] connect_db")
    rv = sqlite3.connect(app.config['DATABASE'])
    rv.row_factory = sqlite3.Row
    logger.debug("[end] connect_db")
    return rv


def init_db():
    logger.debug("[start] init_db")
    with app.app_context():
        db = get_db()
        with app.open_resource('schema.sql', mode='r') as f:
            db.cursor().executescript(f.read())
        db.commit()
    logger.debug("[end] init_db")


def get_db():
    """Opens a new database connection if there is none yet for the current application context."""
    logger.debug("[start] get_db")
    if not hasattr(g, 'db'):
        g.db = connect_db()
    logger.debug("[end] get_db")
    return g.db


# init_db()


@app.teardown_appcontext
def close_db(error):
    """Closes the database again at the end of the request."""
    logger.debug("[start] close_db")
    if hasattr(g, 'db'):
        g.db.close()
    logger.debug("[end] close_db")


@app.route('/')
def show():
    logger.debug("[start] show")
    get_db()
    cur = g.db.execute('select text from queries order by id desc limit 0, 1')
    queries = [dict(query_time=row[0], text=row[1], result=row[2], detail_str=row[3]) for row in cur.fetchall()]
    logger.debug("[end] show")
    return render_template('show.html', entries=queries)


@app.route('/test/', methods=['POST'])
def test():
    logger.debug("[start] test")
    s = request.form['text']
    get_db()
    g.db.execute('insert into queries (text) values (?)', [request.form['text']])
    g.db.commit()
    logger.debug("[end] test")
    return redirect(url_for('show'))

启动控制supervisor

注意环境变量写法

environment=SETTINGS=/home/test/settings.cfg
posted @ 2018-08-07 16:03  匡子语  阅读(...)  评论(...编辑  收藏