Config-validation-&-compilation.md

To validate your mapping in unit tests and in order to help with "Fail Fast" situations, the following strict mapping modes have been added.

Explicit Mapping

Forcing all classes to be explicitly mapped:

//Default is "false"
TypeAdapterConfig.GlobalSettings.RequireExplicitMapping = true;
//This means you have to have an explicit configuration for each class, even if it's just:
TypeAdapterConfig<Source, Destination>.NewConfig();

Checking Destination Member

Forcing all destination properties to have a corresponding source member or explicit mapping/ignore:

//Default is "false"
TypeAdapterConfig.GlobalSettings.RequireDestinationMemberSource = true;

Validating Mappings

Both a specific TypeAdapterConfig<Source, Destination> or all current configurations can be validated. In addition, if Explicit Mappings (above) are enabled, it will also include errors for classes that are not registered at all with the mapper.

//Validate a specific config
var config = TypeAdapterConfig<Source, Destination>.NewConfig();
config.Compile();

//Validate globally
TypeAdapterConfig<Source, Destination>.NewConfig();
TypeAdapterConfig<Source2, Destination2>.NewConfig();
TypeAdapterConfig.GlobalSettings.Compile();

Config Compilation

Mapster will automatically compile mapping for first time usage.

var result = poco.Adapt<Dto>();

However, you can explicitly compile mapping by Compile method.

//Global config
TypeAdapterConfig.GlobalSettings.Compile();

//Config instance
var config = new TypeAdapterConfig();
config.Compile();

Calling Compile method on start up helps you validate mapping and detect problem on start-up time, not on run-time.

NOTE: After compile, when you change setting in config, it will generate errors. Therefore, make sure you finish configuration before calling Compile.