Azure 函数从 Cosmos Db Mongo 集合返回空数据集

我有一个 Azure 函数，它正在查询一个肯定保存数据的 cosmos db mongo 集合。

但是，当通过我的 azure 函数查询时，该函数返回一个空数组。

我的功能看起来像：

    [FunctionName("GetAll")]
    public static IActionResult Run([HttpTrigger(AuthorizationLevel.Function, "get", Route = null)]HttpRequest req, 
        TraceWriter log, [Inject(typeof(IWarehouseStateRepository))]IWarehouseStateRepository repoW)
    {
        log.Info("GetAll Function is processing a request");
        var warehouses = repoW.GetAllWarehouses();
        return warehouses != null ? 
            (ActionResult)new OkObjectResult(warehouses) :
            new BadRequestObjectResult("Something went wrong with this request");
    }

我正在为我的仓库存储库注入一个自定义类型，该类型依赖于如下所示的 db 配置上下文：

public class StateContext : IStateContext
{
    private readonly IMongoDatabase _database = null;
    private readonly string _connectionString;
    private readonly string _dbName;
    private readonly string _collectionName;

    public StateContext()
    {

        _connectionString = Environment.GetEnvironmentVariable("AggregateDbConnectionDev");
        _dbName = Environment.GetEnvironmentVariable("AggregateDbNameDev");
        _collectionName = Environment.GetEnvironmentVariable("AggregateDbCollectionDev");

        MongoClientSettings settings = MongoClientSettings.FromUrl(new MongoUrl(_connectionString));
        settings.SslSettings = new SslSettings() { EnabledSslProtocols = SslProtocols.Tls12 };

        var client = new MongoClient(settings);
        if (client != null)
            _database = client.GetDatabase(_dbName);
    }

    public IMongoCollection<WarehouseState> WarehouseState
    {
        get
        {
            return _database.GetCollection<WarehouseState>(_collectionName);
        }
    }
}

该函数不会引发任何错误或异常。

和回购查询：

    public IEnumerable<WarehouseState> GetAllWarehouses()
    {
        var warehouses = _context.WarehouseState.Find(_ => true).ToList();
        return warehouses;
    }

有没有人知道这里可能出现什么问题？我是否需要使用 azure 功能以不同的方式设置 cosmos Db 连接？

在将逻辑移至 azure 函数之前，此设置已在之前有效。