How to iterate over nested dictionaries in django templates

Question

I\'m not sure the most efficient way to iterate over my nested dictionaries to print a matrix of the total and good values for every fruit for each date. Take for instance

Answer 1

as rolling stone says thats the way to iterate over dictionaries in templates, i would only change the key, value keywords for different keywords in every iteration like this:

{% for key, value in harvest_data.items %}
    {{ key }} <br>
    {% for key2,value2 in value.items %}
        {{ key2 }} <br>
        {% for key3, value3 in value2.items %}
            {{ key3 }}:{{ value3 }} <br>
        {% endfor %}
    {% endfor %}
{% endfor %}

just for the sake of clarity :)

And if you want to line up your values i would suggest you use another data structure where you can sort by date, for example a something like this:

{ 'oranges' : [(date1, value1), (date2,value2)] ...}

Try to do the least possible operations in your templates, so dont do a sort or nested if's if you dont have to

Answer 2

Really old question, but I will add my 1.5c.

This is a good use case of the regroup tag (https://docs.djangoproject.com/en/1.9/ref/templates/builtins/#regroup) and a bit of data refactoring:

1. Have your data as a simple list of data points:

   harvest_data = [
       {'fruits': 'apples', 'date': '2011-07-23', 'total': 100, 'good': 80},
       # ...
   ]
   

2. In your template, group by the chosen dimension(s):

   {% regroup harvest_data by fruits as data_by_fruits %}
   {% for data in data_by_fruits %}
       <h1>{{ data.grouper }}</h1>   # 'apples'
       {% regroup data.list by date as data_by_fruits_date %}
       {% for data_1 in data_by_fruits_date %}
           <h2>{{ data_1.grouper }}</h2>    # '2011-07-23'
           {% for datapoint in data_1.list %}
               total: {{ datapoint.total }} <br/>
               good: {{ datapoint.good }} <br/>
           {% endfor %}
       {% endfor %}
   {% endfor %}
   

Answer 3

Since you're familiar with python, the following is logically how you would want to iterate through your dictionary in a Django template:

for key,value in harvest_data.items():
...     print key
...     for key2,value2 in value.items():
...         print key2
...         for key3,value3 in value2.items():
...             print "%s:%s"%(key3,value3)

In your template, this translates as follows:

{% for key, value in harvest_data.items %}
    {{ key }} <br>
    {% for key2,value2 in value.items %}
        {{ key2 }} <br>
        {% for key3, value3 in value2.items %}
            {{ key3 }}:{{ value3 }} <br>
        {% endfor %}
    {% endfor %}
{% endfor %}

The Django docs actually briefly include an example of how to iterate through dictionaries when describing how the for template tag works:

https://docs.djangoproject.com/en/dev/ref/templates/builtins/#for