Python 3.x Python Flask分页错误：分页页面返回404 错误源代码：

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预期行为 在索引处有一个带有电子邮件和ip的表单，用于搜索和显示响应，响应应分页

main/routes.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 'example@example.com'
    except KeyError as ke:
        session['email'] = 'example@example.com'


@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 'example@example.com':
        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'))

from flask import Blueprint

bp = Blueprint('main', __name__)

from app.main import routes

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))

main/\uuuuu init\uuuuu.py

：

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

from flask import Blueprint

bp = Blueprint('main', __name__)

from app.main import routes

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))

/models.py

：

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

from flask import Blueprint

bp = Blueprint('main', __name__)

from app.main import routes

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))

模板/index.html

：

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


...

{{ render_pagination(pagination) }}

...

实际行为 简而言之，从索引的表单获取结果，然后对其进行分页，但任何分页链接都无法正常工作

我将会话的电子邮件和ip设置为

session['email']

和

session['ip']

。 然后，我单击第2页，按会话将这些关键字搜索到一个对象并分页，但

paginate（）

无法正常工作，链接类似

http://127.0.0.1:5000/index?page=2

，响应错误页面：404

elif

在routes.py中：

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

l=logiimported.query.filter（rule）

的返回类型正确，但

l.paginate（page，per\u page=50，error\u out=True）

抛出错误。 被if阻止的代码工作正常，被elif阻止的代码响应错误

参数

规则

在这两个位置相同。为什么会出现这些错误

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

环境

• Python版本：3.7.1
• 烧瓶版本：1.0.2
• Werkzeug版本：0.14.1

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当您请求的页码高于过滤结果中存在的页数时，会发生此错误。在本例中，您请求的是第2页，带有“l.paginate（page，per_page=50，error_out=True）”（page=2），而实际上结果的数量小于或等于50，因此您只能得到一页

这是一个常见错误，ui请求的页码高于现有的页码。每次搜索时，您都必须将页面重置为1

看下图，行为是相同的（但我得到了标志error_out=False，因此分页返回结果，其中项目为空，即使搜索得到6个项目）

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嘿，你，这里的伟人，对我很有用，非常感谢你！