topic Re: How do I parse children from a hierarchical json file? in Talend Studio

How do I parse children from a hierarchical json file?

pthomas — Mon, 09 Jun 2025 14:12:26 GMT

I have a table for people. Those people have friends who have friends. All people, friend or not, have the same data. The parent has no other friends but does have a column for that. This mirrors the data that I am getting.

If I create a json Metedata schema of "friend" to house the columns (id, name, friendOf, someValue), how can I pull this data into a parquet file or other flat file or db?

To the point, how can I parse this with Talend? How can I use tMap, tExtractJson or other component on an "n" number of levels of the same data?

Hopefully, the json isn't too butchered.

{

"friends": {

"id": 100,

"name": "Bob",

"friendOf": null,

"someValue": "58",

"children": [

{

"id": 101,

"name": "Sue",

"friendOf": "Bob",

"someValue": "123"

{

"id": 102,

"name": "Jan",

"friendOf": "Bob",

"someValue": "99",

"children": [

{

"id": 101,

"name": "Ivy",

"friendOf": "Jan",

"someValue": "10"

}

]

{

"id": 103,

"name": "Jon",

"friendOf": "Bob",

"someValue": "90"

{

"id": 104,

"name": "Ron",

"friendOf": "Bob",

"someValue": "23",

"children": [

{

"id": 105,

"name": "Cal",

"friendOf": "Ron",

"someValue": "777",

"children": [

{

"id": 106,

"name": "Ann",

"friendOf": "Cal",

"someValue": "777"

{

"id": 107,

"name": "Leo",

"friendOf": "Cal",

"someValue": "42"

}

]

}

]

}

]

}

Re: How do I parse children from a hierarchical json file?

Dave_Simo — Fri, 06 Jun 2025 20:05:12 GMT

Hello @pthomas

Use this url to get the correct jsonPath query to parse your json

https://jsonpathfinder.com/

Best Regards

Re: How do I parse children from a hierarchical json file?

pthomas — Mon, 09 Jun 2025 14:14:27 GMT

Thanks for the link. That's great for working with json files. But I need Talend to parse a json into a parquet.

BTW, I've used https://jsonformatter.org/ for working with json files but I'll compare that with pathfinder.

Re: How do I parse children from a hierarchical json file?

Dave_Simo — Mon, 09 Jun 2025 14:46:07 GMT

Hello @pthomas

And which part of the json do you want to parse with the Talend component? The link actually helps you to have the right jsonPath query to use in your tFileInpuJson or tExtractJsonFields.

Best Regards

Re: How do I parse children from a hierarchical json file?

Dave_Simo — Mon, 09 Jun 2025 15:27:58 GMT

Hello @pthomas

For example

Re: How do I parse children from a hierarchical json file?

pthomas — Thu, 12 Jun 2025 16:47:49 GMT

The issue was user! In my example above if "friends" was in square brackets not curly, that would better simulate my issue. Getting the "[*]"s right and the "."s is important. My results were coming back in a comma separated list. Removing a "." from the json query separated them into individual rows.