Parsing json and searching through it

ObjectPath is a library that provides ability to query JSON and nested structures of dicts and lists. For example, you can search for all attributes called “foo” regardless how deep they are by using $..foo.

While the documentation focuses on the command line interface, you can perform the queries programmatically by using the package’s Python internals. The example below assumes you’ve already loaded the data into Python data structures (dicts & lists). If you’re starting with a JSON file or string you just need to use load or loads from the json module first.

import objectpath

data = [
    {'foo': 1, 'bar': 'a'},
    {'foo': 2, 'bar': 'b'},
    {'NoFooHere': 2, 'bar': 'c'},
    {'foo': 3, 'bar': 'd'},
]

tree_obj = objectpath.Tree(data)

tuple(tree_obj.execute('$..foo'))
# returns: (1, 2, 3)

Notice that it just skipped elements that lacked a “foo” attribute, such as the third item in the list. You can also do much more complex queries, which makes ObjectPath handy for deeply nested structures (e.g. finding where x has y that has z: $.x.y.z). I refer you to the documentation and tutorial for more information.

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