IdentifiableMongoDbPersistence<T, K>

Abstract persistence component that stores data in MongoDB and implements a number of CRUD operations over data items with unique ids.

Inherits: MongoDbPersistence, IWriter<T, K>, IGetter<T, K>, ISetter

Description

The IdentifiableMongoDbPersistence class allows you to create persistance components that store data in MongoDB databases and implement a number of CRUD operations over data items with unique ids.

Important points

  • The data items must implement the IIdentifiable interface.
  • In basic scenarios child classes shall only override GetPageByFilterAsync, GetListByFilter or DeleteByFilter operations with specific filter functions.
  • All other operations can be used out of the box.
  • In complex scenarios child classes can implement additional operations by accessing the this._collection property.

Configuration parameters

connection(s):

  • discovery_key: (optional) key to retrieve the connection from IDiscovery
  • host: host name or IP address
  • port: port number (default: 27017)
  • uri: resource URI or connection string with all parameters in it

credential(s):

  • store_key: (optional) key to retrieve the credentials from ICredentialStore
  • username: (optional) username
  • password: (optional) user’s password

options:

  • max_pool_size: (optional) maximum connection pool size (default: 2)
  • keep_alive: (optional) enable connection keep alive (default: true)
  • connect_timeout: (optional) connection timeout in milliseconds (default: 5 sec)
  • auto_reconnect: (optional) enable auto reconnection (default: true)
  • max_page_size: (optional) maximum page size (default: 100)
  • debug: (optional) enable debug output (default: false).

References

  • *:logger:*:*:1.0 - (optional) ILogger components to pass log messages
  • *:discovery:*:*:1.0 - (optional) IDiscovery services
  • *:credential-store:*:*:1.0 - (optional) credential stores used to resolve credentials

Constructors

Creates a new instance of the persistence component.

public IdentifiableMongoDbPersistence(string collectionName)

  • collectionName: string - (optional) collection name.

Fields

InternalIdFieldName

Internal field name

protected InternalIdFieldName: string = = “_id”

Instance methods

CreateAsync

Creates a data item.

public override Task<T> CreateAsync(IContext context, T item)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • item: T - item to be created.
  • returns: Task<T> - created item

DeleteByIdAsync

Deletes a data item by it’s unique id.

public virtual Task<T> DeleteByIdAsync(IContext context, K id)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • id: K - id of the item to be deleted
  • return: Task<T> - deleted item.

DeleteByIdsAsync

Deletes multiple data items by their unique ids.

public virtual Task DeleteByIdsAsync(IContext context, K[] ids)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • ids: K[] - ids of data items to be deleted.

GetListByIdsAsync

Gets a list of data items retrieved by given unique ids.

public virtual Task<List<T>> GetListByIdsAsync(IContext context, K[] ids)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • ids: K[] - ids of data items to be retrieved
  • return: Task<List<T>> - data list of results by ids.

GetOneByIdAsync

Gets a data item by its unique id.

public virtual Task<T> GetOneByIdAsync(IContext context, K id)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • id: K - id of data item to be retrieved.
  • returns: Task<T> - data item.

SetAsync

Sets a data item. If the data item exists, it updates it. Otherwise, it creates a new data item.

public virtual Task<T> SetAsync(IContext context, T item)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • item: T - item to be set.
  • returns: Task<T> - updated item

UpdateAsync

Updates a data item.

public virtual Task<T> UpdateAsync(IContext context, T item)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • item: T - item to be updated.
  • returns: Task<T> - updated item.

Examples

class MyMongoDbPersistence: MongoDbPersistence<MyData, string> 
{
    public MyMongoDbPersistence(): base("mydata") { }

    private FilterDefinition<MyData> ComposeFilter(FilterParams filter)
    {
        filterParams = filterParams ?? new FilterParams();
        var builder = Builders<BeaconV1>.Filter;
        var filter = builder.Empty;
        String name = filter.getAsNullableString("name");
        if (name != null)
            filter &= builder.Eq(b => b.Name, name);
        return filter;
    }
    
    public GetPageByFilter(IContext context, FilterParams filter, PagingParams paging)
    {
        base.GetPageByFilter(context, this.ComposeFilter(filter), paging, null, null);
    }
}

var persistence = new MyMongoDbPersistence();
persistence.Configure(ConfigParams.FromTuples(
    "host", "localhost",
    "port", 27017 )
);

persitence.Open("123");

persistence.Create("123", new MyData("1", "ABC"));
var mydata = persistence.GetPageByFilter(
    "123",
    FilterParams.FromTuples("name", "ABC")
);
Console.Out.WriteLine(mydata.Data);          // Result: { id: "1", name: "ABC" }

persistence.DeleteById("123", "1");
...