How to pass mongodb returned values to javascript array?
Question
I am using flask to render html template.I want to store all items returned by pymongo query into a java script array.I created an array c[] which is empty first.And i used for loop of flask to iterate through returned items of pymongo query and i am pushing it to array c.
I tried some answers of stackoverflow but it dint match understanding of my question
my html code is here:home.html
<html>
<head>
<title>ii</title>
</head>
<script>
var c=[]
{% for todo in collection %}
c.push{{todo["q"]}};
{% endfor %}
</script>
</body>
</html>
my flask file:-
from flask import Flask, render_template,json
from pymongo import MongoClient
from bson import json_util,ObjectId
app = Flask(__name__)
mongo_object = MongoClient("localhost", 27017)
app.debug= True
db = mongo_object['test']
collection = db['myc']
@app.route('/')
def index():
return render_template('home.html')
@app.route('/find',methods=['GET', 'POST'])
def pymongo_data_display():
my_data = collection.find()
a1="active"
return render_template('home.html',a1=a1,collection=my_data,t="hi",h="hoho")
'''
if not my_data:
return 'no data'
else:
return my_data
'''
if __name__ == '__main__':
app.run()
it gives nothing.But can anyone suggest what to do here?
2 answers
solution1
1 2019-04-10 04:42:37
There are couple of things:
- Is
my_datanon-empty where you provide it torender_template? What is the structure of the data? - What is the value of
todo["q"]in the template? Is it a number or a string? If the latter, you will need to wrap it in quotes before pushing into the JavaScript array. - You are missing parentheses in
c.push{{todo["q"]}};.
Let's say that you need to store list of strings in the JavaScript array (ie you need to quote the values before pushing then into the array). Then you need to define custom filter to achieve it. Here's complete example:
import jinja2
def quote(value):
return '"{}"'.format(value)
env = jinja2.Environment()
env.filters['quote'] = quote
template = env.from_string("""
<script>
var c = [];
{% for item in data %}
c.push({{ item.q|quote|safe }});
{% endfor %}
</script>
""")
data = [{'q': 1}, {'q': 2}, {'q': 3}]
print(template.render(data=data))
solution2
1 ACCPTED 2019-04-10 05:48:43
This works:
home.html file:
<html>
<head>
<title>ii</title>
<script>
function populateMyDiv(){
var ul=document.createElement('ul');
{% for name in collection %}
var li=document.createElement('li');
ul.appendChild(li);
li.innerHTML=li.innerHTML + "{{name}}";
{% endfor %}
document.getElementById("test").appendChild(ul);
}
</script>
</head>
<body onload="populateMyDiv()">
<div id="test"></div>
</body>
</html>
test.py file:
from flask import Flask, render_template
from pymongo import MongoClient
import json
app = Flask(__name__)
mongo_obj=MongoClient("localhost", 27017)
@app.route('/')
def hello_world():
db = mongo_obj['your_database']
collection = db['your_collection']
temp = collection.find()
my_data = []
for x in temp:
my_data.append(x['name'])
return render_template('home.html',collection=my_data)
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