feat(graphql): adds @created and @Updated directives for server gener…

…ated mutation timestamps

Adds support for @created and @Updated directives on GraphQL input schema.
Schema gen validates that field is of type `DateTime!`
Schema gen does not add @created and @Updated fields to add/update input types, preventing
modification over GraphQL
Rewrite mutation sets @created fields with current DateTime when node is new, and @Updated fields
any time node is changed.
Non null input checks ignore fields with @created/@Updated metadata

graphql/resolve/add_mutation_test.yaml

@@ -5504,3 +5504,101 @@
          implementing types of same interfaces: T1 and T2"
     }
 
+-
+  name: "Add mutation with @created and @updated directive"
+  gqlmutation: |
+    mutation($input: [AddBookingInput!]!) {
+      addBooking(input: $input) {
+        booking {
+          name
+          created
+          updated
+        }
+      }
+    }
+  gqlvariables: |
+    {
+      "input": [
+        {
+          "name": "Holiday to Bermuda"
+        }
+      ]
+    }
+  explanation: "As booking has @created and @updated directives, these DateTime fields should be populated"
+  dgmutations:
+    - setjson: |
+        {
+            "Booking.created": "2019-10-12T07:20:50.52Z",
+            "Booking.name": "Holiday to Bermuda",
+            "Booking.updated": "2019-10-12T07:20:50.52Z",
+            "dgraph.type": [
+                    "Booking"
+                ],
+            "uid":"_:Booking_1"
+        }
+
+-
+  name: "Upsert mutation with @created and @updated directives where only one of the nodes exists"
+  explanation: "Booking1 should only have updated timestamp as it exists, Booking2 should have created and updated timestamps"
+  gqlmutation: |
+    mutation addBookingXID($input: [AddBookingXIDInput!]!) {
+      addBookingXID(input: $input, upsert: true) {
+        bookingXID {
+          name
+        }
+      }
+    }
+  gqlvariables: |
+    { "input":
+      [
+        {
+          "id": "Booking1",
+          "name": "Trip to Bermuda"
+        },
+        {
+          "id": "Booking2",
+          "name": "Trip to Antigua"
+        }
+      ]
+    }
+  dgquery: |-
+    query {
+      BookingXID_1(func: eq(BookingXID.id, "Booking1")) {
+        uid
+        dgraph.type
+      }
+      BookingXID_2(func: eq(BookingXID.id, "Booking2")) {
+        uid
+        dgraph.type
+      }
+    }
+  qnametouid: |-
+    {
+      "BookingXID_1": "0x11"
+    }
+  dgquerysec: |-
+    query {
+      BookingXID_1 as BookingXID_1(func: uid(0x11)) @filter(type(BookingXID)) {
+        uid
+      }
+    }
+  dgmutations:
+    - setjson: |
+        {
+          "uid" : "uid(BookingXID_1)",
+          "BookingXID.id": "Booking1",
+          "BookingXID.name": "Trip to Bermuda",
+          "BookingXID.updated": "2019-10-12T07:20:50.52Z"
+        }
+      cond: "@if(gt(len(BookingXID_1), 0))"
+    - setjson: |
+        {
+          "uid": "_:BookingXID_2",
+          "BookingXID.id": "Booking2",
+          "BookingXID.name": "Trip to Antigua",
+          "BookingXID.created": "2019-10-12T07:20:50.52Z",
+          "BookingXID.updated": "2019-10-12T07:20:50.52Z",
+          "dgraph.type": [
+            "BookingXID"
+          ]
+        }

graphql/resolve/mutation_rewriter.go

@@ -1598,6 +1598,8 @@ func rewriteObject(
 		}
 	}
 
+	var isNewNode = false;
+
 	// This is not an XID reference. This is also not a UID reference.
 	// This is definitely a new node.
 	// Create new node
@@ -1646,7 +1648,20 @@ func rewriteObject(
 		// "_:Project2" . myUID will store the variable generated to reference this node.
 		newObj["dgraph.type"] = dgraphTypes
 		newObj["uid"] = myUID
+		isNewNode = true
+	}
+
+	var timestamp = "2019-10-12T07:20:50.52Z"
+	// var timestamp = time.Now().Format(time.RFC3339)
+	for _, field := range typ.Fields() {
+		if field.HasCreatedDirective() && isNewNode {
+			newObj[field.DgraphPredicate()] = timestamp
+		}
+		if field.HasUpdatedDirective() {
+			newObj[field.DgraphPredicate()] = timestamp
+		}
 	}
+
 
 	// Add Inverse Link if necessary
 	deleteInverseObject(obj, srcField)

graphql/resolve/schema.graphql

@@ -175,6 +175,21 @@ type Student implements People {
     taughtBy: [Teacher] @hasInverse(field: "teaches")
 }
 
+# For testing created/updated timestamps
+type Booking {
+    id: ID!
+    name: String!
+    created: DateTime! @created
+    updated: DateTime! @updated
+}
+
+type BookingXID {
+    id: String! @id
+    name: String!
+    created: DateTime! @created
+    updated: DateTime! @updated
+}
+
 type Comment {
     id: ID!
     author: String!

graphql/resolve/update_mutation_test.yaml

@@ -2405,3 +2405,38 @@
          "uid": "uid(x)"
        }
     cond: "@if(gt(len(x), 0))"
+
+-
+  name: "Update with @created and @updated directives"
+  gqlmutation: |
+    mutation updateBooking($patch: UpdateBookingInput!) {
+      updateBooking(input: $patch) {
+        booking {
+          id
+        }
+      }
+    }
+  gqlvariables: |
+    { "patch":
+      { "filter": {
+          "id": ["0x123", "0x124"]
+        },
+        "set": {
+          "name": "Flight to Antigua"
+        }
+      }
+    }
+  explanation: "The update patch should include a timestamp on the field with the @updated directive"
+  dgquerysec: |-
+    query {
+      x as updateBooking(func: uid(0x123, 0x124)) @filter(type(Booking)) {
+        uid
+      }
+    }
+  dgmutations:
+    - setjson: |
+        { "uid" : "uid(x)",
+          "Booking.name": "Flight to Antigua",
+          "Booking.updated": "2019-10-12T07:20:50.52Z"
+        }
+      cond: "@if(gt(len(x), 0))"

graphql/schema/gqlschema.go

@@ -48,6 +48,8 @@ const (
 	remoteResponseDirective = "remoteResponse"
 	lambdaDirective         = "lambda"
 	lambdaOnMutateDirective = "lambdaOnMutate"
+	createdDirective        = "created"
+	updatedDirective        = "updated"
 
 	generateDirective       = "generate"
 	generateQueryArg        = "query"
@@ -278,6 +280,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @auth(
@@ -309,6 +313,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @remote on OBJECT | INTERFACE | UNION | INPUT_OBJECT | ENUM
@@ -570,6 +576,8 @@ var directiveValidators = map[string]directiveValidator{
 	remoteDirective:         ValidatorNoOp,
 	deprecatedDirective:     ValidatorNoOp,
 	lambdaDirective:         lambdaDirectiveValidation,
+	createdDirective:        timestampDirectiveValidation,
+	updatedDirective:        timestampDirectiveValidation,
 	lambdaOnMutateDirective: ValidatorNoOp,
 	generateDirective:       ValidatorNoOp,
 	apolloKeyDirective:      ValidatorNoOp,
@@ -1284,7 +1292,7 @@ func addPatchType(schema *ast.Schema, defn *ast.Definition, providesTypeMap map[
 		return
 	}
 
-	nonIDFields := getNonIDFields(schema, defn, providesTypeMap)
+	nonIDFields := getPatchFields(schema, defn, providesTypeMap)
 	if len(nonIDFields) == 0 {
 		// The user might just have an predicate with reverse edge id field and nothing else.
 		// We don't generate patch type in that case.
@@ -2208,7 +2216,7 @@ func createField(schema *ast.Schema, fld *ast.FieldDefinition) *ast.FieldDefinit
 	return &newFld
 }
 
-func getNonIDFields(schema *ast.Schema, defn *ast.Definition, providesTypeMap map[string]bool) ast.FieldList {
+func getPatchFields(schema *ast.Schema, defn *ast.Definition, providesTypeMap map[string]bool) ast.FieldList {
 	fldList := make([]*ast.FieldDefinition, 0)
 	for _, fld := range defn.Fields {
 		if isIDField(defn, fld) {
@@ -2226,6 +2234,11 @@ func getNonIDFields(schema *ast.Schema, defn *ast.Definition, providesTypeMap ma
 		if hasCustomOrLambda(fld) {
 			continue
 		}
+		// Fields with @created/@updated directive should not be part of mutation input,
+		// hence we skip them.
+		if hasCreatedOrUpdated(fld) {
+			continue
+		}
 		// We don't include fields in update patch, which corresponds to multiple language tags in dgraph
 		// Example, nameHi_En:  String @dgraph(pred:"Person.name@hi:en")
 		// We don't add above field in update patch because it corresponds to multiple languages
@@ -2279,7 +2292,12 @@ func getFieldsWithoutIDType(schema *ast.Schema, defn *ast.Definition,
 		if hasCustomOrLambda(fld) {
 			continue
 		}
-		// see the comment in getNonIDFields as well.
+		// Fields with @created/@updated directive should not be part of mutation input,
+		// hence we skip them.
+		if hasCreatedOrUpdated(fld) {
+			continue
+		}
+		// see the comment in getPatchFields as well.
 		if isMultiLangField(fld, true) && isAddingInput {
 			continue
 		}
@@ -2290,7 +2308,7 @@ func getFieldsWithoutIDType(schema *ast.Schema, defn *ast.Definition,
 			continue
 		}
 
-		// see also comment in getNonIDFields
+		// see also comment in getPatchFields
 		if schema.Types[fld.Type.Name()].Kind == ast.Interface &&
 			(!hasID(schema.Types[fld.Type.Name()]) && !hasXID(schema.Types[fld.Type.Name()])) {
 			continue

graphql/schema/gqlschema_test.yml

@@ -2935,6 +2935,26 @@ invalid_schemas:
         "locations": [ { "line": 2, "column": 18 } ] },
     ]
 
+  - name: "@created field must be of type DateTime!"
+    input: |
+      type Person  {
+        created: String @created
+      }
+    errlist: [
+      { "message": "Type Person; Field created: with @created directive must be of type DateTime!, not String",
+        "locations": [ { "line": 2, "column": 20 } ] },
+    ]
+
+  - name: "@updated field must be of type DateTime!"
+    input: |
+      type Person  {
+        updated: String @updated
+      }
+    errlist: [
+      { "message": "Type Person; Field updated: with @updated directive must be of type DateTime!, not String",
+        "locations": [ { "line": 2, "column": 20 } ] },
+    ]
+
 valid_schemas:
   - name: "Multiple fields with @id directive should be allowed"
     input: |

graphql/schema/rules.go

@@ -1291,6 +1291,21 @@ func lambdaDirectiveValidation(sch *ast.Schema,
 	return errs
 }
 
+func timestampDirectiveValidation(sch *ast.Schema,
+	typ *ast.Definition,
+	field *ast.FieldDefinition,
+	dir *ast.Directive,
+	secrets map[string]x.Sensitive) gqlerror.List {
+	if field.Type.NamedType == "DateTime" && field.Type.NonNull {
+		return nil
+	}
+	return []*gqlerror.Error{gqlerror.ErrorPosf(
+		dir.Position,
+		"Type %s; Field %s: with @%s directive must be of type DateTime!, not %s",
+		typ.Name, field.Name, dir.Name, field.Type.String())}
+
+}
+
 func lambdaOnMutateValidation(sch *ast.Schema, typ *ast.Definition) gqlerror.List {
 	dir := typ.Directives.ForName(lambdaOnMutateDirective)
 	if dir == nil {

graphql/schema/testdata/apolloservice/output/auth-directive.graphql

@@ -193,6 +193,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @remote on OBJECT | INTERFACE | UNION | INPUT_OBJECT | ENUM

graphql/schema/testdata/apolloservice/output/custom-directive.graphql

@@ -185,6 +185,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @remote on OBJECT | INTERFACE | UNION | INPUT_OBJECT | ENUM

graphql/schema/testdata/apolloservice/output/extended-types.graphql

@@ -199,6 +199,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @remote on OBJECT | INTERFACE | UNION | INPUT_OBJECT | ENUM

graphql/schema/testdata/apolloservice/output/generate-directive.graphql

@@ -195,6 +195,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @remote on OBJECT | INTERFACE | UNION | INPUT_OBJECT | ENUM

graphql/schema/testdata/apolloservice/output/single-extended-type.graphql

@@ -180,6 +180,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @remote on OBJECT | INTERFACE | UNION | INPUT_OBJECT | ENUM

graphql/schema/testdata/schemagen/input/created-updated-directives.graphql

@@ -0,0 +1,13 @@
+type Booking {
+    id: ID!
+    name: String!
+    created: DateTime! @created
+    updated: DateTime! @updated
+}
+
+type BookingXID {
+    id: String! @id
+    name: String!
+    created: DateTime! @created
+    updated: DateTime! @updated
+}

graphql/schema/testdata/schemagen/output/apollo-federation.graphql

@@ -215,6 +215,8 @@ directive @hasInverse(field: String!) on FIELD_DEFINITION
 directive @search(by: [DgraphIndex!]) on FIELD_DEFINITION
 directive @dgraph(type: String, pred: String) on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @id(interface: Boolean) on FIELD_DEFINITION
+directive @created on FIELD_DEFINITION
+directive @updated on FIELD_DEFINITION
 directive @withSubscription on OBJECT | INTERFACE | FIELD_DEFINITION
 directive @secret(field: String!, pred: String) on OBJECT | INTERFACE
 directive @auth(