DynamoQuery

Helper for building Boto3 DynamoDB queries.

• DynamoQuery
  • Installation
  • Usage
    • DynamoQuery
    • DynamoTable
  • Development
    • VSCode
    • PyCharm
  • Versioning

Installation

python -m pip install dynamoquery

Usage

You can find commented usage examples in examples directory.

DynamoQuery

import boto3

from dynamo_query import DynamoQuery, DataTable

table_resource = boto3.resource("dynamodb").Table('people')
query = DynamoQuery.build_scan(
    filter_expression=ConditionExpression('first_name') & ('last_name', 'in'),
).limit(
    5,
).projection(
    'first_name', 'last_name', 'age',
).table(
    table_resource=table_resource,
    table_keys=('pk', ),
)
...

# simple query
data = {
    'first_name': 'John',
    'last_name': ['Cena', 'Doe', 'Carmack'],
}

result_data_table = query.execute_dict(data)
for record in result_data_table.get_records():
    print(record)

# batch get
data_table = DataTable.create().add_record(
    {"pk": "my_pk"},
    {"pk": "my_pk2"},
    {"pk": "my_pk3"},
)

result_data_table = query.execute(data_table)
for record in result_data_table.get_records():
    print(record)

DynamoTable

from typing import Optional
from dynamo_query import DynamoTable, DynamoDictClass

# first, define your record
@dataclass
class UserRecord(DynamoDictClass):
    pk: str
    email: str
    name: str
    points: Optional[int] = None

    @DynamoDictClass.compute_key("pk")
    def get_pk(self) -> str:
        return self.email


# Create your dynamo table manager with your record class
class UserTable(DynamoTable[UserRecord]):
    # provide a set of your table keys
    table_keys = {'pk'}
    record_class = UserRecord

    # use this property to define your table resource
    @property
    def table(self) -> Any:
        return boto3.resource("dynamodb").Table("user_table")


# okay, let's start using our manager
user_table = UserTable()

# add a new record to your table
user_table.upsert_record(
    UserRecord(
        email="user@gmail.com",
        name="John User",
        age=12,
    )
)

# and output all the records
for user_record in user_table.scan():
    print(user_record)

Development

Install dependencies with pipenv

python -m pip install pipenv
pipenv install -d

Enable pylint and mypy checks in your IDE.

Run unit tests and linting.

./scripts/before_commit.sh

Add false-positive unused entities to vulture whitelist

vulture dynamo_query --make-whitelist > vulture_whitelist.py

VSCode

Recommended .vscode/settings.json

{
  "python.pythonPath": "<pipenv_path>/bin/python",
  "python.linting.pylintEnabled": true,
  "python.linting.enabled": true,
  "python.linting.mypyEnabled": true,
  "python.formatting.provider": "black"
}

PyCharm

• Install mypy unofficial extension
• Install blackextension, enable format on save
• Run pylint on save

Versioning

dynamo_query version follows Semantic Versioning.