jinja2 - Jinja parsing a nested JSON

Question

This is my first attempt at using Jinja or anything Python related, but our vendor has a new tool implemented that uses it, so here we are.

As a test, I'm using a free API as a data source and want to convert it through the tool's Jinja. API is http://www.floatrates.com/daily/usd.json...

{"eur":{
    "code":"EUR",
    "alphaCode":"EUR",
    "numericCode":"978",
    "name":"Euro",
    "rate":0.90140326265491,
    "date":"Tue, 21 Jan 2020 12:00:01 GMT",
    "inverseRate":1.1093813850359},
"gbp":{
    "code":"GBP",
    "alphaCode":"GBP",
    "numericCode":"826",
    "name":"U.K. Pound Sterling",
    "rate":0.76735727130961,
    "date":"Tue, 21 Jan 2020 12:00:01 GMT",
    "inverseRate":1.3031739417721},
"jpy":{
    "code":"JPY",
    "alphaCode":"JPY",
    "numericCode":"392",
    "name":"Japanese Yen",
    "rate":109.99188913429,
    "date":"Tue, 21 Jan 2020 12:00:01 GMT",
    "inverseRate":0.009091579459819}...

My goal is to iterated through the content (which this tool has the response's body in the content property) and grab the code and eventual rate for each one. I know what to do once I can successfully get those values... Here is what I have so far

{% set Collection = a.content|to_json %}
{% for obj in Collection %}
{% set CurrentObject = obj %}
{{ Collection[CurrentObject].code }}
{% endfor %}

This doesn't appear to work however... if I do a.content|to_json['eur'].code then I get the EUR as a value, but I'm trying to not hardcode for each iteration.

Thanks in advance.

Answer 1

I don't think you want that to_json filter there. That's for producing a JSON representation of a data structure. You don't want that; you actually want the data structure.

If you have the data in your question in the content property, you could write something like this:

{% for code in content %}
{{ code }} {{ content[code].rate }}
{% endfor %}

This would give you:

eur 0.90140326265491

gbp 0.76735727130961

jpy 109.99188913429

This is the code I'm using to test:

import jinja2


content = {
    "eur": {
        "code": "EUR",
        "alphaCode": "EUR",
        "numericCode": "978",
        "name": "Euro",
        "rate": 0.90140326265491,
        "date": "Tue, 21 Jan 2020 12:00:01 GMT",
        "inverseRate": 1.1093813850359,
    },
    "gbp": {
        "code": "GBP",
        "alphaCode": "GBP",
        "numericCode": "826",
        "name": "U.K. Pound Sterling",
        "rate": 0.76735727130961,
        "date": "Tue, 21 Jan 2020 12:00:01 GMT",
        "inverseRate": 1.3031739417721,
    },
    "jpy": {
        "code": "JPY",
        "alphaCode": "JPY",
        "numericCode": "392",
        "name": "Japanese Yen",
        "rate": 109.99188913429,
        "date": "Tue, 21 Jan 2020 12:00:01 GMT",
        "inverseRate": 0.009091579459819,
    },
}


t = jinja2.Template('''{% for code in content %}
{{ code }} {{ content[code].rate }}
{% endfor %}''')

print(t.render(content=content))