CosmosQuery 0.1.0

CosmosQuery

Creates LINQ expressions from ODataQueryOptions and executes the query. This library uses AutoMapper's Queryable Extentions to project from your DTO (Data Transfer Object) to your entities.

Usage

<b>Step1</b>

<hr>

Set up your DTO to Entity mappings for AutoMapper so that it can correctly project the incoming OData query from your DTO type(s) to your Entity type(s).

<br>

If you only want to include properties explicitly (E.g., the consumer of the API has to explicitly $select which properties they want included in the results) then make sure to enable Explicit expansion on your properties.

    public class Mappings : AutoMapper.Profile
    {
        public Mappings()
        {
            CreateMap<Entity, DTO>()
                .ForMember(d => d.Name, o => o.MapFrom(s => s.FullName))                
                .ForAllMembers(o => o.ExplicitExpansion());
        }
    }

<b>Step2</b>

<hr>

Set up the actions on your controller(s) to accept a ODataQueryOptions. <br> Do not decorate your actions with the [EnableQuery] attribute as this will result in some operations being applied more than once.

public class MyController : ODataController
{
    private readonly CosmosClient _client;
    private readonly IMapper _mapper;

    public MyController(CosmosClient client, IMapper mapper)
    {
        _client = client;
        _mapper = mapper;
    }

    [HttpGet]
    public async Task<IActionResult> Get(ODataQueryOptions<DTO> options)
    {
        var container = _client.GetContainer("DatabaseID", "ContainerID");
        var query = container.GetItemLinqQueryable<Entity>();
        return Ok(await query.GetQueryAsync(_mapper, options));
    }
}

And thats it, you're done. The query is mapped to your entitiy type before query execution. <br> The query and results are correctly mapped to and from your DTO type(s) and your Entity type(s). This keeps your entities from beging publically exposed via the API.

Functions

There are four main functions you can use depending on your usecase.

• Get - Executes the query aginst the database synchronously
• GetAsync - Executes the query against the database asynchronously
• GetQuery - Synchronously builds the IQueryable but does not execute it against the database
• GetQueryAsync - Asynchronously builds the IQueryable but does not execute it against the database

<b>If you plan on using the synchronous versions of the functions above make sure you've enabled synchronous execution:</b>

var container = _client.GetContainer("DatabaseID", "ContainerID");
var query = container.GetItemLinqQueryable<Entity>(allowSynchronousQueryExecution: true);

Function Signatures

public static ICollection<TModel> Get<TModel, TData>(
    this IQueryable<TData> query, 
    IMapper mapper, 
    ODataQueryOptions<TModel> options, 
    QuerySettings? querySettings = null);

public static IQueryable<TModel> GetQuery<TModel, TData>(
    this IQueryable<TData> query,
    IMapper mapper,
    ODataQueryOptions<TModel> options,
    QuerySettings? querySettings = null)

public static async Task<ICollection<TModel>> GetAsync<TModel, TData>(
    this IQueryable<TData> query, 
    IMapper mapper, 
    ODataQueryOptions<TModel> options, 
    QuerySettings? querySettings = null);

public static async Task<IQueryable<TModel>> GetQueryAsync<TModel, TData>(
    this IQueryable<TData> query, 
    IMapper mapper, 
    ODataQueryOptions<TModel> options, 
    QuerySettings? querySettings = null);