CSV Repository

CSV (Comma-separated values file) repository is a data store in which each item represents a row in the given CSV file.

With dict:

from redbird.repos import CSVFileRepo
repo = CSVFileRepo(filename="my_repo.csv", fieldnames=['id', 'name', 'age'])

Warning

CSV files don’t maintain the data types. All field values are considered str and empty values are considered None. It is adviced to use Pydantic model (see below) instead if the type matters.

With Pydantic model:

from pydantic import BaseModel
from redbird.repos import CSVFileRepo

class MyItem(BaseModel):
    id: str
    name: str
    age: int

repo = CSVFileRepo(filename="my_repo.csv", model=MyItem)

Usage

Now you may use the repository the same way as any other repository. Please see:

• Reading the repository

• Creating an item to the repository

• Deleting an item from the repository

• Updating an item in the repository

Class

class redbird.repos.CSVFileRepo(*, model=<class 'dict'>, id_field=None, query_model=<class 'redbird.base.BasicQuery'>, errors_query='raise', field_access='infer', ordered=True, filename, fieldnames=None, kwds_csv={})

CSV file repository

This repository has a CSV (comma-separated values) file as a data store. Each item represents a row in the file.

Parameters

• filename (path-like) – The repository file

• fieldnames (list of str) – Names of the columns in the CSV file. If unspecified, model’s fields are used instead

• model (Type) – Class of an item in the repository. Commonly dict or subclass of Pydantic BaseModel. By default dict

• id_field (str, optional) – Attribute or key that identifies each item in the repository.

• field_access ({'attr', 'key'}, optional) – How to access a field in an item. Either by attribute (‘attr’) or key (‘item’). By default guessed from the model.

• query (Type, optional) – Query model of the repository.

• errors_query ({'raise', 'warn', 'discard'}) – Whether to raise an exception, warn or discard the item in case of validation error in converting data to the item model from the repository. By default raise

• kwds_csv (dict) – Keyword arguments used to create csv.DictWriter and csv.DictReader

Examples

repo = CSVFileRepo(filepath="path/to/repo", fieldnames=['id', 'name', 'age'])

insert(item)

Insert item to the repository

Parameters

item (instance of model) – Item to insert to the repository

Examples

repo.insert(Item(id="a", color="red"))

filter_by(**kwargs)

Filter the repository

Parameters

**kwargs (dict) – Query which is used to conduct furher operation.

Examples

repo.filter_by(color="red")

update(item)

Update item in the repository

Parameters

item (instance of model) – Item to update in the repository

Examples

repo.update(Item(id="a", color="red"))

delete(item)

Delete item from the repository

Parameters

item (instance of model) – Item to delete from the repository

Examples

repo.delete(Item(id="a", color="red"))