Jinja2 - How to loop a json list? - json

Question

How can I loop a json list with jinja2?
I have this json list,
[
{
"first_name": "John",
"last_name": "Smith",
"user_id": 4,
"address": null
},
{
"first_name": "Jane",
"last_name": "Heart",
"user_id": 5,
"address": null
},
{
"first_name": "Dom",
"last_name": "Robinsons",
"user_id": 6,
"address": null
},
{
"first_name": "Pete",
"last_name": "Hand",
"user_id": 7,
"address": null
}
]
page.html,
<table>
{% for user in users %}
<tr><td>{{ user.first_name }}</td></tr>
{% endfor %}
</table>
Result,
<table>
<tr><td></td></tr>
<tr><td></td></tr>
<tr><td></td></tr>
<tr><td></td></tr>
...
Any ideas?

Answer 1

your json list contains dictionaries; you need to access the dictionary elements differently than you would class members; try:
<tr><td>{{ user['first_name'] }}</td></tr>
this works for me (python 3.4 and python 2.7)
import json
from jinja2 import Template
json_str = '''[{"first_name": "John", "last_name": "Smith", "user_id": 4,
"address": null}, {"first_name": "Jane", "last_name": "Heart",
"user_id": 5, "address": null}, {"first_name": "Dom",
"last_name": "Robinsons", "user_id": 6, "address": null},
{"first_name": "Pete", "last_name": "Hand", "user_id": 7,
"address": null}]'''
users = json.loads(json_str)
tmpl = Template('''
<table>
{% for user in users %}
<tr><td>{{ user['first_name'] }}</td></tr>
{% endfor %}
</table>
''')
print(tmpl.render(users = users))
output:
<table>
<tr><td>John</td></tr>
<tr><td>Jane</td></tr>
<tr><td>Dom</td></tr>
<tr><td>Pete</td></tr>
</table>

Answer 2

simple json iteration in jinja2
<table>
<tr>
{% for key in users[0] %}
<th>{{ key }}</th>
{% endfor %}
</tr>
{% for user in users %}
<tr>
{% for key in user %}
<td>{{ user[key] }}</td>
{% endfor %}
</tr>
{% endfor %}
</table>