Remove objects with duplicate property

Question

I have 'data' which is this array of objects:

{
"data": [
    {
        "name": "Erich",
        "fruit": "apple"
    },
    {
        "name": "Fred",
        "fruit": "orange"
    },
    {
        "name": "Erich",
        "fruit": "grape"
    },   
        "name": "Fred",
        "fruit": "banana"
    }
]}

Using only Jinja templating, I want to remove the objects with duplicate values for the "name" key, resulting in this:

{
"data": [
    {
        "name": "Erich",
        "fruit": "apple"
    },
    {
        "name": "Fred",
        "fruit": "orange"
    }
]}

At this point I don't care which of the duplicate objects is removed (e.g. apple vs grape or orange vs. banana) but if there is a way to use some logic with another KVP to decide, I would be interested in knowing how.

Answer 1

You can use the unique filter:

{% for item in data|unique(attribute='name') %}
{{ item }}
{% endfor %}

You can see that in action in the following code:

import jinja2

t = jinja2.Template(
    """
{% for item in data|unique(attribute='name') %}
{{ item }}
{% endfor %}
"""
)

context = {
    "data": [
        {"name": "Erich", "fruit": "apple"},
        {"name": "Fred", "fruit": "orange"},
        {"name": "Erich", "fruit": "grape"},
        {"name": "Fred", "fruit": "banana"},
    ]
}

print(t.render(**context))

Which prints out:

{'name': 'Erich', 'fruit': 'apple'}

{'name': 'Fred', 'fruit': 'orange'}