dictflat 0.2.3

A Python library to flatten a dictionary with nested dictionnaries and lists

dictflat

A Python library to flatten a dictionary with nested dictionnaries and lists

Use cases

Transform a dictionary structure into a new organization ready to be inserted into a relational database.

Installation

poetry add dictflat

Quick start

>>> from dictflat import DictFlat
>>> import json
>>> r = DictFlat(
    root_key="root"
).flat(
    d={
        "name": "John",
        "pers_id": 12,
        "birth": {
            "address": {
                "street": "123 Main St",
                "city": "Anytown",
                "state": "CA"
            },
            "date": "10/06/1976 01:10:35"
        },
        "Phone_Numbers": [
            {"type": "home", "number": "555-1234"},
            {"type": "work", "number": "555-5678"},
        ],
    }
)
>>> print("%s" % json.dumps(r, indent=2))
{
  "root": [
    {
      "__id": "662783f7-b1a0-4e8c-9de9-f3a72a896d4c",
      "name": "John",
      "pers_id": 12
    }
  ],
  "root.birth": [
    {
      "__id": "e72d549a-89f5-4208-99c0-4ce3493cbf9e",
      "__ref__root": "662783f7-b1a0-4e8c-9de9-f3a72a896d4c",
      "date": "10/06/1976 01:10:35"
    }
  ],
  "root.birth.address": [
    {
      "__id": "cc489c03-82ca-4b6e-a620-32c9c4be236c",
      "__ref__root.birth": "e72d549a-89f5-4208-99c0-4ce3493cbf9e",
      "street": "123 Main St",
      "city": "Anytown",
      "state": "CA"
    }
  ],
  "root.Phone_Numbers": [
    {
      "__id": "ba1560de-9c4c-4886-b4ca-684e0a7e5df0",
      "__ref__root": "662783f7-b1a0-4e8c-9de9-f3a72a896d4c",
      "type": "home",
      "number": "555-1234"
    },
    {
      "__id": "f1032025-6c7d-4341-8e6a-f0dce2374388",
      "__ref__root": "662783f7-b1a0-4e8c-9de9-f3a72a896d4c",
      "type": "work",
      "number": "555-5678"
    }
  ]
}

The result is always a dictionary where each key is a reference to the original dictionary.

• In this example, the original root document is identified by the token “root” (the root key) and the "address" sub-dictionary is identified by “root.address”.

Each dictionary value is always a list. See below for more examples with more than one element in lists.

Each sub-dictionnary have:

• an unique field named "__id" (like a primary key)
• except for root, a "__ref__root" who contains the "__id" value of parent dictionnary;
  • the "root" token in "__ref__root" field name is directly a reference to the global result dictionnary.

Documentation

All examples explained in documentation come from module tests.

1. Basic usages
2. Nested dictionnaries
3. Generate IDs
4. Change values
5. Drop fields
6. Rename fields
7. Lists
8. Squash dictionnaries
9. Simple keys