feature: Adds NoDeprecatedCustomRule

Author: NeedleInAJayStack

Sources/GraphQL/Validation/Rules/Custom/NoDeprecatedCustomRule.swift

@@ -0,0 +1,87 @@
+
+/**
+ * No deprecated
+ *
+ * A GraphQL document is only valid if all selected fields and all used enum values have not been
+ * deprecated.
+ *
+ * Note: This rule is optional and is not part of the Validation section of the GraphQL
+ * Specification. The main purpose of this rule is detection of deprecated usages and not
+ * necessarily to forbid their use when querying a service.
+ */
+public func NoDeprecatedCustomRule(context: ValidationContext) -> Visitor {
+    return Visitor(
+        enter: { node, _, _, _, _ in
+            if let node = node as? Field {
+                if
+                    let fieldDef = context.fieldDef,
+                    let deprecationReason = fieldDef.deprecationReason,
+                    let parentType = context.parentType
+                {
+                    context.report(
+                        error: GraphQLError(
+                            message: "The field \(parentType.name).\(fieldDef.name) is deprecated. \(deprecationReason)",
+                            nodes: [node]
+                        )
+                    )
+                }
+            }
+            if let node = node as? Argument {
+                if
+                    let argDef = context.argument,
+                    let deprecationReason = argDef.deprecationReason
+                {
+                    if let directiveDef = context.typeInfo.directive {
+                        context.report(
+                            error: GraphQLError(
+                                message: "Directive \"@\(directiveDef.name)\" argument \"\(argDef.name)\" is deprecated. \(deprecationReason)",
+                                nodes: [node]
+                            )
+                        )
+                    } else if
+                        let fieldDef = context.fieldDef,
+                        let parentType = context.parentType
+                    {
+                        context.report(
+                            error: GraphQLError(
+                                message: "Field \"\(parentType.name).\(fieldDef.name)\" argument \"\(argDef.name)\" is deprecated. \(deprecationReason)",
+                                nodes: [node]
+                            )
+                        )
+                    }
+                }
+            }
+            if let node = node as? ObjectField {
+                let inputObjectDef = context.parentInputType as? GraphQLInputObjectType
+                
+                if
+                    let inputObjectDef = context.parentInputType as? GraphQLInputObjectType,
+                    let inputFieldDef = inputObjectDef.fields[node.name.value],
+                    let deprecationReason = inputFieldDef.deprecationReason
+                {
+                    context.report(
+                        error: GraphQLError(
+                            message: "The input field \(inputObjectDef.name).\(inputFieldDef.name) is deprecated. \(deprecationReason)",
+                            nodes: [node]
+                        )
+                    )
+                }
+            }
+            if let node = node as? EnumValue {
+                if
+                    let enumValueDef = context.typeInfo.enumValue,
+                    let deprecationReason = enumValueDef.deprecationReason,
+                    let enumTypeDef = getNamedType(type: context.inputType)
+                {
+                    context.report(
+                        error: GraphQLError(
+                            message: "The enum value \"\(enumTypeDef.name).\(enumValueDef.name)\" is deprecated. \(deprecationReason)",
+                            nodes: [node]
+                        )
+                    )
+                }
+            }
+            return .continue
+        }
+    )
+}