Flask入门文件上传flask-uploads(八)

return render_template(‘模板名称.html‘,arg1=val1,arg2=val2...)

dict = {
    key1:value1,
    key2:value2,
    ....
}
return render_template(‘模板名称.html‘,dict)

@app.route(‘/test‘)
def test():
    g.name = ‘张三‘
    g.sex = ‘男‘
    return render_template(‘test.html‘)

 <h2>{{ g.name }}</h2>
 <h2>{{ g.sex }}</h2>

@app.route(‘/test‘)
def test():
    name = ‘张三‘
    sex = ‘男‘
    return render_template(‘test.html‘,**locals())

<h2>{{ name }}</h2>
<h2>{{ sex }}</h2>

#制定捕获404和500的错误页面
@app.errorhandler(404)
def page_not_found(e):
    return render_template(‘error.html‘,error=e,code=404)

@app.errorhandler(500)
def page_not_found(e):  #接受参数e,并传给错误error
    return render_template(‘error.html‘,error=e,code=500)

{% extends ‘common/boot_base.html‘ %}
{% block title %}
{{ code }}  #标题显示500
{% endblock %}
{% block page_content %}
    <div class="alert alert-danger" role="alert">{{ error }}  #显示错误页面信息
</div>
{% endblock %}

{{ url_for(‘static‘,filename=‘img/mei.jpg‘) }} 
{{ url_for(‘static‘,filename=‘css/style.css‘) }} 
{{ url_for(‘static‘,filename=‘js/mei.js‘) }} 

#注:static是内置的视图函数,我们通过其找到路由

{% if newName %}  #newName非空 图片名传入
    <img src=‘{{ url_for("static",filename=newName) }}‘ alt=‘‘>
{% endif %}
#视图函数upLoad  
<form action="{{ url_for(‘upLoad‘) }}" enctype=‘multipart/form-data‘ method=‘post‘>
    <input type=‘file‘ name=‘file‘>
    <p><input type=‘submit‘ value=‘submit‘></p>
</form>

from flask import Flask,render_template,request
from flask_script import Manager
from flask_bootstrap import Bootstrap
import os
from PIL import Image  #python图片处理库

app = Flask(__name__)
#允许上传的后缀名,放在配置文件
app.config[‘ALLOWED_EXTENSIONS‘] = [‘.jpg‘,‘.jpeg‘,‘.png‘,‘.gif‘]
#上传文件的大小
app.config[‘MAX_CONTENT_LENGTH‘] = 1024*1024*60
#配置文件上传的路径
app.config[‘UPLOAD_FOLDER‘] = os.getcwd() + ‘/static‘

#绑定bootstrap
bootstrap = Bootstrap(app)
manager = Manager(app)

@app.route(‘/‘)
def index():
    return render_template(‘index.html‘)

#生成随机图片名称的函数
def new_name(shuffix,length=32):
    import string,random
    myStr = string.ascii_letters + ‘0123456789‘
    newName = ‘‘.join(random.choice(myStr) for i in range(length))
    return newName+shuffix

#定义判断后缀是否可用函数,返回true/false
def allowed_file(shuffix):
    return shuffix in app.config[‘ALLOWED_EXTENSIONS‘]

@app.route(‘/upload‘,methods=[‘GET‘,‘POST‘])
def upload():
    img_name = None
    if request.method == ‘POST‘:
        file = request.files.get(‘file‘)
        #获取上传文件的名称
        filename = file.filename
        #分割路径，返回路径名和文件扩展名的元组
        shuffix = os.path.splitext(filename)[-1]
        if allowed_file(shuffix):
            #为真则生成随机名称
            newName = new_name(shuffix)
            img_name = newName
            #拼凑完整的路径
            newPath = os.path.join(app.config[‘UPLOAD_FOLDER‘],newName)
            file.save(newPath)
            
            #处理图片的缩放
            img = Image.open(newPath)
            #重新设置大小与尺寸
            img.thumbnail((200,200))
            img.save(newName)
     #跳转上传页面并返回newName
     return render_template(‘upload.html‘,newName=img_name)

pip3 install flask-uploads

{% extends ‘common/base.html‘ %}  #继承
{% block title %}
    首页
{% endblock %}
{% import ‘bootstrap/wtf.html‘ as wtf %}  #导入
{% block page_content %}
    <img src="{{ url_for(‘static‘,filename=newName) }}" alt="">
    {{ wtf.quick_form(form) }}   #快速渲染
{% endblock %}

from flask import Flask,render_template,request
from flask_script import Manager
from flask_bootstrap import Bootstrap
import os
from flask_uploads import UploadSet,IMAGES,configure_uploads,patch_request_class
#导入库中验证的字段类
from flask_wtf import FlaskForm
from wtforms import FileField,SubmitField
from flask_wtf.file import FileAllowed,FileRequired

app = Flask(__name__)
#允许上传的后缀
app.config[‘SECRET_KEY‘] = ‘image‘
app.config[‘MAX_CONTENT_LENGTH‘] = 1024*1024*64 #64兆
#配置文件上传的路径
app.config[‘UPLOADED_PHOTOS_DEST‘] = os.getcwd()+‘/static/upload‘

#实例化一个file对象  photos与PHOTOS要对应
file = UploadSet(‘photos‘,IMAGES)
#将 app 的 config 配置注册到 UploadSet 实例 file
configure_uploads(app,file)
#限制上传文件的大小   size=None不采用默认size=64*1024*1024
patch_request_class(app,size=None)

bootstrap = Bootstrap(app)
manager = Manager(app)

class File(FlaskForm):
    file = FileField(‘文件上传‘,validators=[FileRequired(message=‘您还没有选择文件‘),FileAllowed(file,message=‘只能上擦图片‘)])
    submit = SubmitField(‘上传‘)

#生成随机图片名称的函数
def new_name(shuffix,length=32):
    import string, random
    myStr = string.ascii_letters + ‘0123456789‘
    newName = ‘‘.join(random.choice(myStr) for i in range(length))
    return newName+shuffix

@app.route(‘/upload‘,methods=[‘GET‘,‘POST‘])
def upload():
    form = File()
    img_url = None
    #验证数据
    if form.validate_on_submit():
        shuffix = os.path.splitext(form.file.data.filename)[-1]
        newName = new_name(shuffix=shuffix)
        file.save(form.file.data,name=newName)
        img_url = file.url(newName)
    return  render_template(‘boot_upload.html‘,newName=img_url,form=form)

if __name__ == ‘__main__‘:
    manager.run()