Add CHECK constraint support

Improved encapsulation for CheckConstraint annotations

src/EFCore.Design/Migrations/Design/CSharpMigrationOperationGenerator.cs

@@ -384,6 +384,45 @@ protected virtual void Generate([NotNull] AddUniqueConstraintOperation operation
             }
         }
 
+        /// <summary>
+        ///     Generates code for an <see cref="CreateCheckConstraintOperation" />.
+        /// </summary>
+        /// <param name="operation"> The operation. </param>
+        /// <param name="builder"> The builder code is added to. </param>
+        protected virtual void Generate([NotNull] CreateCheckConstraintOperation operation, [NotNull] IndentedStringBuilder builder)
+        {
+            Check.NotNull(operation, nameof(operation));
+            Check.NotNull(builder, nameof(builder));
+
+            builder.AppendLine(".CreateCheckConstraint(");
+
+            using (builder.Indent())
+            {
+                builder
+                    .Append("name: ")
+                    .Append(Code.Literal(operation.Name));
+
+                if (operation.Schema != null)
+                {
+                    builder
+                        .AppendLine(",")
+                        .Append("schema: ")
+                        .Append(Code.Literal(operation.Schema));
+                }
+
+                builder
+                    .AppendLine(",")
+                    .Append("table: ")
+                    .Append(Code.Literal(operation.Table))
+                    .AppendLine(",")
+                    .Append("constraintSql: ")
+                    .Append(Code.Literal(operation.ConstraintSql))
+                    .Append(")");
+
+                Annotations(operation.GetAnnotations(), builder);
+            }
+        }
+
         /// <summary>
         ///     Generates code for an <see cref="AlterColumnOperation" />.
         /// </summary>
@@ -1039,6 +1078,23 @@ protected virtual void Generate([NotNull] CreateTableOperation operation, [NotNu
                         builder.AppendLine(";");
                     }
 
+                    foreach (var checkConstraints in operation.CheckConstraints)
+                    {
+                        builder
+                            .Append("table.CheckConstraint(")
+                            .Append(Code.Literal(checkConstraints.Name))
+                            .Append(", ")
+                            .Append(Code.Literal(checkConstraints.ConstraintSql))
+                            .Append(")");
+
+                        using (builder.Indent())
+                        {
+                            Annotations(checkConstraints.GetAnnotations(), builder);
+                        }
+
+                        builder.AppendLine(";");
+                    }
+
                     foreach (var foreignKey in operation.ForeignKeys)
                     {
                         builder.AppendLine("table.ForeignKey(");
@@ -1380,6 +1436,42 @@ protected virtual void Generate([NotNull] DropUniqueConstraintOperation operatio
             }
         }
 
+        /// <summary>
+        ///     Generates code for a <see cref="DropCheckConstraintOperation" />.
+        /// </summary>
+        /// <param name="operation"> The operation. </param>
+        /// <param name="builder"> The builder code is added to. </param>
+        protected virtual void Generate([NotNull] DropCheckConstraintOperation operation, [NotNull] IndentedStringBuilder builder)
+        {
+            Check.NotNull(operation, nameof(operation));
+            Check.NotNull(builder, nameof(builder));
+
+            builder.AppendLine(".DropCheckConstraint(");
+
+            using (builder.Indent())
+            {
+                builder
+                    .Append("name: ")
+                    .Append(Code.Literal(operation.Name));
+
+                if (operation.Schema != null)
+                {
+                    builder
+                        .AppendLine(",")
+                        .Append("schema: ")
+                        .Append(Code.Literal(operation.Schema));
+                }
+
+                builder
+                    .AppendLine(",")
+                    .Append("table: ")
+                    .Append(Code.Literal(operation.Table))
+                    .Append(")");
+
+                Annotations(operation.GetAnnotations(), builder);
+            }
+        }
+
         /// <summary>
         ///     Generates code for a <see cref="RenameColumnOperation" />.
         /// </summary>

src/EFCore.Relational/Metadata/ICheckConstraint.cs

@@ -0,0 +1,36 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+namespace Microsoft.EntityFrameworkCore.Metadata
+{
+    /// <summary>
+    ///     Represents a check constraint in the <see cref="IModel" />.
+    /// </summary>
+    public interface ICheckConstraint
+    {
+        /// <summary>
+        ///     Gets the name of the check constraint in the database.
+        /// </summary>
+        string Name { get; }
+
+        /// <summary>
+        ///     The database table that contains the check constraint.
+        /// </summary>
+        string Table { get; }
+
+        /// <summary>
+        ///     The database table schema that contains the check constraint.
+        /// </summary>
+        string Schema { get; }
+
+        /// <summary>
+        ///     The <see cref="IModel" /> in which this check constraint is defined.
+        /// </summary>
+        IModel Model { get; }
+
+        /// <summary>
+        ///     Gets the constraint sql used in a check constraint in the database.
+        /// </summary>
+        string ConstraintSql { get; }
+    }
+}

src/EFCore.Relational/Metadata/IRelationalModelAnnotations.cs

@@ -24,6 +24,18 @@ public interface IRelationalModelAnnotations
         /// </returns>
         ISequence FindSequence([NotNull] string name, [CanBeNull] string schema = null);
 
+        /// <summary>
+        ///     Finds an <see cref="ICheckConstraint" /> with the given name.
+        /// </summary>
+        /// <param name="name"> The check constraint name. </param>
+        /// <param name="table"> The table that contains the check constraint. </param>
+        /// <param name="schema"> The table schema that contains the check constraint. </param>
+        /// <returns>
+        ///     The <see cref="ICheckConstraint" /> or <c>null</c> if no check constraint with the given name in
+        ///     the given schema was found.
+        /// </returns>
+        ICheckConstraint FindCheckConstraint([NotNull] string name, [NotNull] string table, [CanBeNull] string schema = null);
+
         /// <summary>
         ///     Finds a <see cref="IDbFunction" /> that is mapped to the method represented by the given <see cref="MethodInfo" />.
         /// </summary>
@@ -36,6 +48,11 @@ public interface IRelationalModelAnnotations
         /// </summary>
         IReadOnlyList<ISequence> Sequences { get; }
 
+        /// <summary>
+        ///     All <see cref="ICheckConstraint" />s contained in the model.
+        /// </summary>
+        IReadOnlyList<ICheckConstraint> CheckConstraints { get; }
+
         /// <summary>
         ///     All <see cref="IDbFunction" />s contained in the model.
         /// </summary>