Python 的 Flask 框架用 paginate 分页返回404？

Question

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问题描述

在 index 页面有一个表单，用于查询 email 并将查询结果返回到该页面，并分页.提交表单后，结果确实分页了，但是点击任何分页都是404错误页。

你期待的结果是什么？

index 页提交查询表单，然后在 index 页显示结果，结果正确分页。

相关代码

源代码:https://github.com/wedojava/e...

main/index.py:

from flask import render_template, flash, redirect, url_for, request, g, current_app, session
from app.main import bp
from app.main.forms import SearchForm

@bp.before_app_request
def before_request():
    if current_user.is_authenticated:
        current_user.last_seen = datetime.utcnow()
        db.session.commit()
    
    try:
        session['email'] = session['email'] if session['email'] else '[e-mail]'
    except KeyError as ke:
        session['email'] = '[e-mail]'


@bp.route('/', methods=['GET', 'POST'])
@bp.route('/index', methods=['GET', 'POST'])
def index():
    form = SearchForm()
    page = request.args.get('page', 1, type=int)
    if form.validate_on_submit():
        words_email = ["%" + form.email.data + "%"]
        rule_email = and_(*[LogImported.sender_address.like(w) for w in words_email])
        # pay attention these two lines below:
        l = LogImported.query.filter(rule_email)
        pagination = l.paginate(page, per_page=50, error_out=True)
        pageitems = pagination.items
        session['email'] = form.email.data
        return render_template('index.html', title=_('Home'), form=form, loglist = l, \
        pageitems = pageitems, pagination = pagination)
    elif session['email'] is not '[e-mail]':
        words_email = ["%" + form.email.data + "%"]
        rule_email = and_(*[LogImported.sender_address.like(w) for w in words_email])
        # pay attention these two lines below:
        l = LogImported.query.filter(rule_email)
        pagination = l.paginate(page, per_page=50, error_out=True)
        pageitems = pagination.items
        session['email'] = form.email.data
        return render_template('index.html', title=_('Home'), form=form, loglist = l, \
        pageitems = pageitems, pagination = pagination)
    else:
        return render_template('index.html', title=_('Home'), form=form)

main/forms.py:

class SearchForm(FlaskForm):
    email = StringField(_l('Email'))
    ip = StringField('IP', validators=[Length(min=0, max=140)])
    submit = SubmitField(_l('Submit'))

main/__init__.py:

from flask import Blueprint

bp = Blueprint('main', __name__)

from app.main import routes

/models.py:

class LogImported(db.Model):
    id = db.Column(db.Integer, index=True, primary_key=True)
    date = db.Column(db.DateTime, default=datetime.utcnow)
    sender_address = db.Column(db.String(255), index=True)
    recipient_address = db.Column(db.String(255))
    recipient_count = db.Column(db.Integer)
    return_path = db.Column(db.String(255))
    client_hostname = db.Column(db.String(255))
    client_ip = db.Column(db.String(100))
    server_hostname = db.Column(db.String(255))
    server_ip = db.Column(db.String(100))
    original_client_ip = db.Column(db.String(100))
    original_server_ip = db.Column(db.String(100))
    event_id = db.Column(db.String(50))
    total_bytes = db.Column(db.Integer)
    connector_id = db.Column(db.String(50))
    message_subject = db.Column(db.String(255))
    source = db.Column(db.String(50))

templates/index.html:

{% extends "base.html" %}
{% from 'bootstrap/form.html' import render_form %}
{% from 'bootstrap/pagination.html' import render_pagination %}


...

{{ render_pagination(pagination) }}

...

结果分页会404

从 index 页面查询，把获得的结果集分页，但是点击分页就报错404。

我把查询关键字放到 session 里，然后点击分页的时候，从session读取关键字，查询，把结果交给分页函数去分页，但是 paginate() 会报错。类似 http://127.0.0.1:5000/index?page=2 ，会返回404错误页面。

elif in routes.py:

l = LogImported.query.filter(rule)
pagination = l.paginate(page, per_page=50, error_out=True)

l = LogImported.query.filter(rule) 的类型是对的，但是 l.paginate(page, per_page=50, error_out=True) 会报错，结果都取到了，分页就出错了。if 里写的可以，elif里一模一样的就不能行。

实际看到的错误信息又是什么？

127.0.0.1 - - [11/Dec/2018 12:44:51] "GET /index?page=2 HTTP/1.1" 404 -

问题出现的环境背景及自己尝试过哪些方法

• Python version: 3.7.1
• Flask version:1.0.2
• Werkzeug version:0.14.1

Answer 1

hello，我也出现了同样的错误，查询第一页没问题，查询第二页也没问题，但是从第二页开始，搜索就报错，请问，你解决了吗？