How to pass data from Flask view to HTML?

B

BogBel2015-10-08 22:53:20

Flask

BogBel, 2015-10-08 22:53:20

It is necessary to build a chart according to the data that is transmitted from the view.
Here she is:

@app.route('/hello')
def getting():
    lst = []
    for raw in session.query(DataStoring).descending(DataStoring.population).limit(20):
        lst.append(raw)
    return render_template('chart.html', cities=lst)

For more clarity, I will show another model

class DataStoring(Document):
    _id = StringField()
    city = StringField()
    population = IntField()
    state = StringField()

    mongo_id = _id

    def __str__(self):
        return 'Id=%s City=%s  Population=%s State=%s ' % (self._id, self.city, self.population, self.state)

Actually, like this, I pass the data array to the template

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <link rel="stylesheet" type="text/css" href="/static/style.css">
    <title></title>
    <script src="http://d3js.org/d3.v3.js"></script>

</head>
<body>
{% for city in cities %}
<P>{{ city.city }}:{{ city.population }}</P>
{% endfor %}
<div class="chart"></div>
<script>
   
    var data=[];


    {% for city in cities %}
    
        data.push( {city:{{city.city}}, population:{{ city.population }} });
        console.log({{ city.city }});
        console.log({{ city.population }});
    {% endfor %}


   // var data=[10,20,30,40,50,60,70];
    d3.select(".chart")
  .selectAll("div")
    .data(data)
  .enter().append("div")
    .style("width", function(d) { return d/110 + "px"; })
    .text(function(d) { return d.population+d.city; });

</script>

</body>
</html>

At the moment, the area where the {{city.city}} is accessed is important.
When inside <script></script>I try to access this data, I get an error in the browser console.

While if I refer to int population, then everything is fine, there are no errors.
And yet, when I publish information immediately <p></p>outside the script, then everything is fine.
It is very likely that the problem is that there is a space in the title.
Although it's stupid.