/// <summary>
/// Generates data context constructors.
/// </summary>
/// <param name="contextBuilder">Data context class builder.</param>
/// <param name="initSchemasMethodName">(Optional) additional schemas init method name.</param>
private void BuildDataContextConstructors(
ClassBuilder contextBuilder,
CodeIdentifier?initSchemasMethodName)
{
var constructors = contextBuilder.Constructors();
var ctors = new List <BlockBuilder>();
// based on selected constructors set we generate (or not) following constructors:
// .ctor() // default constructor
// .ctor(string configuration) // constructor with connection configuration name parameter
// .ctor(LinqToDBConnectionOptions options) // options constructor
// .ctor(LinqToDBConnectionOptions<T> options) // typed options constructor
// first we generate empty constructors and then add body to all of them as they will have same code for body
if (_dataModel.DataContext.HasDefaultConstructor)
{
ctors.Add(constructors.New().SetModifiers(Modifiers.Public).Body());
}
if (_dataModel.DataContext.HasConfigurationConstructor)
{
var configurationParam = AST.Parameter(
WellKnownTypes.System.String,
AST.Name(CONTEXT_CONSTRUCTOR_CONFIGURATION_PARAMETER),
CodeParameterDirection.In);
ctors.Add(constructors
.New()
.Parameter(configurationParam)
.SetModifiers(Modifiers.Public)
.Base(configurationParam.Reference)
.Body());
}
if (_dataModel.DataContext.HasUntypedOptionsConstructor)
{
var optionsParam = AST.Parameter(
WellKnownTypes.LinqToDB.Configuration.LinqToDBConnectionOptions,
AST.Name(CONTEXT_CONSTRUCTOR_OPTIONS_PARAMETER),
CodeParameterDirection.In);
ctors.Add(constructors
.New()
.Parameter(optionsParam)
.SetModifiers(Modifiers.Public)
.Base(optionsParam.Reference)
.Body());
}
if (_dataModel.DataContext.HasTypedOptionsConstructor)
{
var typedOptionsParam = AST.Parameter(
WellKnownTypes.LinqToDB.Configuration.LinqToDBConnectionOptionsWithType(contextBuilder.Type.Type),
AST.Name(CONTEXT_CONSTRUCTOR_OPTIONS_PARAMETER),
CodeParameterDirection.In);
ctors.Add(constructors
.New()
.Parameter(typedOptionsParam)
.SetModifiers(Modifiers.Public)
.Base(typedOptionsParam.Reference)
.Body());
}
// partial init method, called by all constructors, which could be used by user to add
// additional initialization logic
var initDataContext = contextBuilder
.Methods(true)
.New(AST.Name(CONTEXT_INIT_METHOD))
.SetModifiers(Modifiers.Partial);
foreach (var body in ctors)
{
// each constructor calls:
// InitSchemas(); // for context with additional schemas
// InitDataContext(); // partial method for custom initialization
if (initSchemasMethodName != null)
{
body.Append(AST.Call(contextBuilder.Type.This, initSchemasMethodName));
}
body.Append(AST.Call(contextBuilder.Type.This, initDataContext.Method.Name));
}
}
/// <summary>
/// Generates table function mapping.
/// </summary>
/// <param name="tableFunction">Function model.</param>
/// <param name="functionsGroup">Functions region.</param>
/// <param name="context">Data context class.</param>
private void BuildTableFunction(
TableFunctionModel tableFunction,
RegionGroup functionsGroup,
CodeClass context)
{
// generated code sample:
/*
* #region Function1
* private static readonly MethodInfo _function1 = MemberHelper.MethodOf<DataContext>(ctx => ctx.Function1(default));
*
* [Sql.TableFunction("Function1")]
* public IQueryable<Parent> Function1(int? id)
* {
* return this.GetTable<Parent>(this, _function1, id);
* }
* #endregion
*/
// create function region
var region = functionsGroup.New(tableFunction.Method.Name);
// if function schema load failed, generate error pragma with exception details
if (tableFunction.Error != null)
{
if (_options.DataModel.GenerateProceduresSchemaError)
{
region.Pragmas().Add(AST.Error($"Failed to load return table schema: {tableFunction.Error}"));
}
// as we cannot generate table function without knowing it's schema, we skip failed function
return;
}
// if function result schema matches known entity, we use entity class for result
// otherwise we generate custom record mapping
if (tableFunction.Result == null || tableFunction.Result.CustomTable == null && tableFunction.Result.Entity == null)
{
throw new InvalidOperationException($"Table function {tableFunction.Name} result record type not set");
}
// GetTable API for table functions need MethodInfo instance of generated method as parameter
// to not load it on each call, we cache MethodInfo instance in static field
var methodInfo = region
.Fields(false)
.New(AST.Name(tableFunction.MethodInfoFieldName), WellKnownTypes.System.Reflection.MethodInfo)
.Private()
.Static()
.ReadOnly();
// generate mapping method with metadata
var method = DefineMethod(region.Methods(false), tableFunction.Method);
_metadataBuilder.BuildTableFunctionMetadata(tableFunction.Metadata, method);
// generate method parameters, return type and body
// table record type
IType returnEntity;
if (tableFunction.Result.Entity != null)
{
returnEntity = _entityBuilders[tableFunction.Result.Entity].Type.Type;
}
else
{
returnEntity = BuildCustomResultClass(tableFunction.Result.CustomTable !, region.Classes(), true).resultClassType;
}
// set return type
// T4 used ITable<T> for return type, but there is no reason to use ITable<T> over IQueryable<T>
// Even more: ITable<T> is not correct return type here
var returnType = _options.DataModel.TableFunctionReturnsTable
? WellKnownTypes.LinqToDB.ITable(returnEntity)
: WellKnownTypes.System.Linq.IQueryable(returnEntity);
method.Returns(returnType);
// parameters for GetTable call in mapping body
var parameters = new ICodeExpression[3 + tableFunction.Parameters.Count];
parameters[0] = context.This; // `this` extension method parameter
parameters[1] = context.This; // context parameter
parameters[2] = methodInfo.Field.Reference; // method info field
// add table function parameters (if any)
var fieldInitParameters = new ICodeExpression[tableFunction.Parameters.Count];
for (var i = 0; i < tableFunction.Parameters.Count; i++)
{
var param = tableFunction.Parameters[i];
// parameters added to 3 places:
// - to mapping method
// - to GetTable call in mapping
// - to mapping call in MethodInfo initializer we add parameter's default value
var parameter = DefineParameter(method, param.Parameter);
parameters[i + 3] = parameter.Reference;
// TODO: potential issue: target-typed `default` could cause errors with overloads
fieldInitParameters[i] = AST.Default(param.Parameter.Type, true);
}
// generate mapping body
method.Body()
.Append(
AST.Return(
AST.ExtCall(
WellKnownTypes.LinqToDB.DataExtensions,
WellKnownTypes.LinqToDB.DataExtensions_GetTable,
WellKnownTypes.LinqToDB.ITable(returnEntity),
new[] { returnEntity },
false,
parameters)));
// generate MethodInfo field initializer
var lambdaParam = AST.LambdaParameter(AST.Name(TABLE_FUNCTION_METHOD_INFO_CONTEXT_PARAMETER), context.Type);
// Expression<Func<context, returnType>>
var lambda = AST
.Lambda(WellKnownTypes.System.Linq.Expressions.Expression(WellKnownTypes.System.Func(returnType, context.Type)), true)
.Parameter(lambdaParam);
lambda.Body()
.Append(
AST.Return(
AST.Call(
lambdaParam.Reference,
method.Method.Name,
returnType,
fieldInitParameters)));
methodInfo.AddInitializer(
AST.Call(
new CodeTypeReference(WellKnownTypes.LinqToDB.Expressions.MemberHelper),
WellKnownTypes.LinqToDB.Expressions.MemberHelper_MethodOf,
WellKnownTypes.System.Reflection.MethodInfo,
new[] { functionsGroup.OwnerType.Type },
false,
lambda.Method));
// TODO: similar tables
}
