Map and Combine JSON objects in Python

Question

Still learning Python and trying to combine 2 JSON objects.

Primary Data Set:

{
    "form-fields": [
        {"type": "text", "x-position": 0, "y-position": 0, "field": "buyer-1"},
        {"type": "text", "x-position": 0, "y-position": 10, "field": "buyer-2"}
    ]
}

Secondary Data Set:

{
    "form-data": [
        {"field": "buyer-1", "value": "John Smith"},
        {"field": "buyer-2", "value": "Susan Smith"}
    ]
}

Intended Result: With "value" appended to the original object.

{
    "form-fields": [
        {"type": "text", "x-position": 0, "y-position": 0, "field": "buyer-1", "value": "John Smith"},
        {"type": "text", "x-position": 0, "y-position": 10, "field": "buyer-2", "value": "Susan Smith"}
    ]
}

like merging element at first index with first index element.. and second with second index element? — Nandha
– Nandha, Commented Jun 11, 2022 at 17:58

Hai Vu · Accepted Answer · 2022-06-11 18:06:38Z

3

I assume that the fields are not in order between primary and secondary. The plan is to create a dictionary call update where key=field and value=secondary's value. Then update the primary.

primary = {
    "form-fields": [
        {"type": "text", "x-position": 0, "y-position": 0, "field": "buyer-1"},
        {"type": "text", "x-position": 0, "y-position": 10, "field": "buyer-2"}
    ]
}

secondary = {
    "form-data": [
        {"field": "buyer-1", "value": "John Smith"},
        {"field": "buyer-2", "value": "Susan Smith"}
    ]
}

update = {
    record["field"]: record["value"]
    for record in secondary["form-data"]
}
# update is {'buyer-1': 'John Smith', 'buyer-2': 'Susan Smith'}

for record in primary["form-fields"]:
    if record["field"] in update:
        record["value"] = update[record["field"]]

The result is primary to become

{
    "form-fields": [
        {
            "type": "text",
            "x-position": 0,
            "y-position": 0,
            "field": "buyer-1",
            "value": "John Smith"
        },
        {
            "type": "text",
            "x-position": 0,
            "y-position": 10,
            "field": "buyer-2",
            "value": "Susan Smith"
        }
    ]
}

answered Jun 11, 2022 at 18:06

Hai Vu

41.4k16 gold badges75 silver badges106 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Parker Over a year ago

Hai Vu - thanks so much for this great answer! This was exactly what I was looking for. I learned a lot from @Nandha's answer, but your solution makes more sense because the field's may not be in order and need to match exactly on their key values. I marked your answer as the accepted answer. Thanks a million sir!

Nandha · Accepted Answer · 2022-06-11 18:02:39Z

2

Assuming length and index will be same in both dictionaries,

primary = {
    "form-fields": [
        {"type": "text", "x-position": 0, "y-position": 0, "field": "buyer-1"},
        {"type": "text", "x-position": 0, "y-position": 10, "field": "buyer-2"}
    ]
}

sec = {
    "form-data": [
        {"field": "buyer-1", "value": "John Smith"},
        {"field": "buyer-2", "value": "Susan Smith"}
    ]
}

pl = primary.get("form-fields")
sl = sec.get("form-data")

for index, prim_val in enumerate(pl):
    sec_val = sl[index]
    prim_val.update(sec_val)
    
print(primary)

Sample code for merging dictionaries

marks = {'Physics':67, 'Maths':87}
internal_marks = {'Practical':48}

marks.update(internal_marks)


print(marks)

# Output: {'Physics': 67, 'Maths': 87, 'Practical': 48}

answered Jun 11, 2022 at 18:02

Nandha

8821 gold badge18 silver badges45 bronze badges

1 Comment

Parker Over a year ago

Nandha this was a very elegant solution. Thank you so much for the thoughtful response! I didn't know about enumerate, so I added print statements in the for loop for print(index, prim_val) and print(sl[index]). I ended up accepting Hai Vu's answer only because the order might not be the same. For example the buyer-2 might come before buyer-1 in the form-data. I wasn't super specific in my original post, so apologies for that. I definitely learned a lot from your answer with enumerate and the sample code for merging dictionaries. Thank you!!!

Collectives™ on Stack Overflow

Map and Combine JSON objects in Python

2 Answers 2

1 Comment

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related