query-handler 1.0.3

This package contains Query DTO and Model Enums

QueryDTO and Related Classes

This repository contains a Python implementation of classes used for querying and filtering data models with the help of the Pydantic library. These classes aim to provide a standardized way to build flexible and reusable query objects, with support for sorting, filtering, pagination, and field population.

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Table of Contents

• Features
• Classes
  • Model Enum
  • Sort Class
  • Filter Class
  • Populate Class
  • Pagination Class
  • QueryDTO Class
• Usage
• Installation
• License

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Features

• Model Identification: Enumerate specific models using the Model enum class.
• Sorting: Specify fields and order (ascending/descending).
• Filtering: Create flexible queries using operators, fields, and values.
• Population: Specify which fields to include in the query.
• Pagination: Limit results by defining page numbers and sizes.
• Logical Operations: Define whether filters use AND or OR operations.

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Classes

Model Enum

The Model Enum class defines constants for different models or entities.

class Model(Enum):
    blog = 1
    appliance = 2
    brand = 3
    product = 4
    faq = 5
    contact = 6
    advice_article = 7

Sort Class

Defines sorting parameters for a query.

class Sort(BaseModel):
    field: str  # Field to sort by
    order: str  # Order ('asc' for ascending, 'desc' for descending)

Filter Class

Defines filters to be applied to a query.

class Filter(BaseModel):
    operator: str  # Logical operator (e.g., 'eq', 'eqi', 'contains', 'notNull', 'and','or')
    field: str     # Field to filter by
    value: str     # Value to compare the field with

Populate Class

Specifies fields to include in the query response.

class Populate(BaseModel):
    field: str  # Field name to populate

Pagination Class

Defines pagination parameters for a query.

class Pagination(BaseModel):
    page: int      # Current page number
    pagesize: int  # Number of records per page

QueryDTO Class

The main Data Transfer Object (DTO) class for constructing queries. It includes options for model identification, filters, sorting, pagination, and field population.

class QueryDTO(BaseModel):
    model: Optional[int] = None  # Entity or module name (from the Model enum)
    id: Optional[int] = None  # -1 for list, >0 for specific record ID
    slug: Optional[str] = None  # Slug URLs
    sorts: Optional[List[Sort]] = None  # List of sorting parameters
    filters: Optional[List[Filter]] = None  # List of filters
    union_filter_operator: Optional[str] = "and"  # Logical operator ('and', 'or')
    populate: Optional[List[Populate]] = None  # Fields to include
    pagination: Optional[Pagination] = None  # Pagination details

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Usage

To use these classes, import them into your project and instantiate them as needed. For example:

from your_module import QueryDTO, Sort, Filter, Populate, Pagination

# Example query
query = QueryDTO(
    model=1,  # Refers to 'blog'
    id=-1,  # Fetch a list
    sorts=[Sort(field="created_at", order="desc")],
    filters=[
        Filter(operator="=", field="status", value="published"),
        Filter(operator=">=", field="created_at", value="2023-01-01")
    ],
    union_filter_operator="and",
    populate=[Populate(field="author")],
    pagination=Pagination(page=1, pagesize=10)
)

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Installation

1. Clone the repository.
2. Ensure you have Python 3.7 or later installed.
3. Install Pydantic:

   pip install pydantic
   

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License

This project is licensed under the MIT License. Feel free to use and modify it as needed.