feat: add @removeNullVariables directives (#477)

* fix: upgrade graphql-go-tools with input coercion fix

* chore: add errors with explanation text to operation parse, normalize and validate stages

* chore: fmt

* chore: add removeNullVariables directive to base schema

* chore: add remove null variables directive description to docs

* chore: update graphql-go-tools to v1.60.3

* chore: update base grapphql schema docs for @removeNullVariable directive

* chore: update test snapshots

* chore: fix node tests, update goldie

* chore: fmt

docs-website/src/pages/docs/directives-reference/index.md

@@ -19,4 +19,5 @@ isIndexFile: true
 {% quick-link title="@export directive" icon="core" href="/docs/directives-reference/export-directive" description="Export a field value into Variables" /%}
 {% quick-link title="@internal directive" icon="core" href="/docs/directives-reference/internal-directive" description="Hide a variable from the external API" /%}
 {% quick-link title="@transform directive" icon="core" href="/docs/directives-reference/transform-directive" description="Lodash style response transformations" /%}
+{% quick-link title="@removeNullVariables directive" icon="core" href="/docs/directives-reference/remove-null-variables-directive" description="Removes null variables query" /%}
 {% /quick-links %}

docs-website/src/pages/docs/directives-reference/remove-null-variables-directive.md

@@ -0,0 +1,28 @@
+---
+title: '@removeNullVariables Directive'
+pageTitle: WunderGraph - Directives - @removeNullVariables
+description:
+---
+
+The `@removeNullVariables` directive allows you to remove variables with null value from your GraphQL Query or Mutation Operations.
+
+A potential use-case could be that you have a graphql upstream which is not accepting null values for variables.
+By enabling this directive all variables with null values will be removed from upstream query.
+
+```graphql
+query ($say: String, $name: String) @removeNullVariables {
+  hello(say: $say, name: $name)
+}
+```
+
+The directive `@removeNullVariables` will transform variables json and remove top level null values.
+
+```json
+{ "say": null, "name": "world" }
+```
+
+So upstream will receive the following variables:
+
+```json
+{ "name": "world" }
+```

go.mod

@@ -36,15 +36,15 @@ require (
 	github.com/prisma/prisma-client-go v0.16.2
 	github.com/qri-io/jsonschema v0.2.1
 	github.com/rs/cors v1.7.0
-	github.com/sebdah/goldie v0.0.0-20180424091453-8784dd1ab561
+	github.com/sebdah/goldie/v2 v2.5.3
 	github.com/segmentio/ksuid v1.0.4
 	github.com/spf13/cobra v1.1.3
 	github.com/spf13/viper v1.10.1
 	github.com/stretchr/testify v1.8.0
 	github.com/tidwall/gjson v1.11.0
 	github.com/tidwall/sjson v1.1.5
 	github.com/valyala/fasthttp v1.26.0
-	github.com/wundergraph/graphql-go-tools v1.60.1
+	github.com/wundergraph/graphql-go-tools v1.60.3
 	go.uber.org/zap v1.18.1
 	golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2
 	golang.org/x/oauth2 v0.0.0-20211104180415-d3ed0bb246c8

go.sum

@@ -445,9 +445,8 @@ github.com/ryanuber/columnize v0.0.0-20160712163229-9b3edd62028f/go.mod h1:sm1tb
 github.com/savsgio/gotils v0.0.0-20200608150037-a5f6f5aef16c h1:2nF5+FZ4/qp7pZVL7fR6DEaSTzuDmNaFTyqp92/hwF8=
 github.com/savsgio/gotils v0.0.0-20200608150037-a5f6f5aef16c/go.mod h1:TWNAOTaVzGOXq8RbEvHnhzA/A2sLZzgn0m6URjnukY8=
 github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529/go.mod h1:DxrIzT+xaE7yg65j358z/aeFdxmN0P9QXhEzd20vsDc=
-github.com/sebdah/goldie v0.0.0-20180424091453-8784dd1ab561 h1:IY+sDBJR/wRtsxq+626xJnt4Tw7/ROA9cDIR8MMhWyg=
-github.com/sebdah/goldie v0.0.0-20180424091453-8784dd1ab561/go.mod h1:lvjGftC8oe7XPtyrOidaMi0rp5B9+XY/ZRUynGnuaxQ=
 github.com/sebdah/goldie/v2 v2.5.3 h1:9ES/mNN+HNUbNWpVAlrzuZ7jE+Nrczbj8uFRjM7624Y=
+github.com/sebdah/goldie/v2 v2.5.3/go.mod h1:oZ9fp0+se1eapSRjfYbsV/0Hqhbuu3bJVvKI/NNtssI=
 github.com/segmentio/ksuid v1.0.4 h1:sBo2BdShXjmcugAMwjugoGUdUV0pcxY5mW4xKRn3v4c=
 github.com/segmentio/ksuid v1.0.4/go.mod h1:/XUiZBD3kVx5SmUOl55voK5yeAbBNNIed+2O73XgrPE=
 github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
@@ -528,8 +527,8 @@ github.com/vmihailenco/msgpack/v5 v5.1.0 h1:+od5YbEXxW95SPlW6beocmt8nOtlh83zqat5
 github.com/vmihailenco/msgpack/v5 v5.1.0/go.mod h1:C5gboKD0TJPqWDTVTtrQNfRbiBwHZGo8UTqP/9/XvLI=
 github.com/vmihailenco/tagparser v0.1.2 h1:gnjoVuB/kljJ5wICEEOpx98oXMWPLj22G67Vbd1qPqc=
 github.com/vmihailenco/tagparser v0.1.2/go.mod h1:OeAg3pn3UbLjkWt+rN9oFYB6u/cQgqMEUPoW2WPyhdI=
-github.com/wundergraph/graphql-go-tools v1.60.1 h1:n/ZyidgnU1wfjeruQ3SUjOaoYzo+kmYKmbcwpHKNjEg=
-github.com/wundergraph/graphql-go-tools v1.60.1/go.mod h1:kHPC4B6vQFMohnEofRgcy37eYhoDsjzxJ4P8ZhQrV4M=
+github.com/wundergraph/graphql-go-tools v1.60.3 h1:HNKjKJ80MhEHx6ODeTogU/sS2ukMzkZPA2b4gF9PlVg=
+github.com/wundergraph/graphql-go-tools v1.60.3/go.mod h1:kHPC4B6vQFMohnEofRgcy37eYhoDsjzxJ4P8ZhQrV4M=
 github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f h1:J9EGpcZtP0E/raorCMxlFGSTBrsSlaDGf3jU/qvAE2c=
 github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f/go.mod h1:N2zxlSyiKSe5eX1tZViRH5QA0qijqEDrYZiPEAiq3wU=
 github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 h1:EzJWgHovont7NscjpAxXsDA8S8BMYve8Y5+7cuRE7R0=

packages/sdk/src/definition/__snapshots__/graphql-introspection.test.ts.snap

@@ -919,6 +919,25 @@ type Query",
   ],
   "Schema": "directive @fromClaim(name: Claim) on VARIABLE_DEFINITION
 
+"""
+The @removeNullVariables directive allows you to remove variables with null value from your GraphQL Query or Mutation Operations.
+
+A potential use-case could be that you have a graphql upstream which is not accepting null values for variables.
+By enabling this directive all variables with null values will be removed from upstream query.
+
+query ($say: String, $name: String) @removeNullVariables {
+	hello(say: $say, name: $name)
+}
+
+Directive will transform variables json and remove top level null values.
+{ "say": null, "name": "world" }
+
+So upstream will receive the following variables:
+
+{ "name": "world" }
+"""
+directive @removeNullVariables on QUERY | MUTATION
+
 directive @hooksVariable on VARIABLE_DEFINITION
 
 directive @jsonSchema(
@@ -2155,6 +2174,25 @@ type Query",
   ],
   "Schema": "directive @fromClaim(name: Claim) on VARIABLE_DEFINITION
 
+"""
+The @removeNullVariables directive allows you to remove variables with null value from your GraphQL Query or Mutation Operations.
+
+A potential use-case could be that you have a graphql upstream which is not accepting null values for variables.
+By enabling this directive all variables with null values will be removed from upstream query.
+
+query ($say: String, $name: String) @removeNullVariables {
+	hello(say: $say, name: $name)
+}
+
+Directive will transform variables json and remove top level null values.
+{ "say": null, "name": "world" }
+
+So upstream will receive the following variables:
+
+{ "name": "world" }
+"""
+directive @removeNullVariables on QUERY | MUTATION
+
 directive @hooksVariable on VARIABLE_DEFINITION
 
 directive @jsonSchema(

packages/sdk/src/definition/merge.ts

@@ -80,6 +80,25 @@ directive @fromClaim(
   name: Claim
 ) on VARIABLE_DEFINITION
 
+"""
+The @removeNullVariables directive allows you to remove variables with null value from your GraphQL Query or Mutation Operations.
+
+A potential use-case could be that you have a graphql upstream which is not accepting null values for variables.
+By enabling this directive all variables with null values will be removed from upstream query.
+
+query ($say: String, $name: String) @removeNullVariables {
+	hello(say: $say, name: $name)
+}
+
+Directive will transform variables json and remove top level null values.
+{ "say": null, "name": "world" }
+
+So upstream will receive the following variables:
+
+{ "name": "world" }
+"""
+directive @removeNullVariables on QUERY | MUTATION
+
 enum Claim {
 	USERID
   EMAIL

pkg/apihandler/apihandler.go

@@ -402,7 +402,7 @@ func (r *Builder) operationApiPath(name string) string {
 }
 
 func (r *Builder) registerInvalidOperation(name string) {
-	apiPath := r.operationApiPath((name))
+	apiPath := r.operationApiPath(name)
 	route := r.router.Methods(http.MethodGet, http.MethodPost, http.MethodOptions).Path(apiPath)
 	route.Handler(&EndpointUnavailableHandler{
 		OperationName: name,
@@ -439,14 +439,17 @@ func (r *Builder) registerOperation(operation *wgpb.Operation) error {
 	shared.Parser.Parse(shared.Doc, shared.Report)
 
 	if shared.Report.HasErrors() {
-		return shared.Report
+		return fmt.Errorf(ErrMsgOperationParseFailed, shared.Report)
 	}
 
 	shared.Normalizer.NormalizeNamedOperation(shared.Doc, r.definition, []byte(operation.Name), shared.Report)
+	if shared.Report.HasErrors() {
+		return fmt.Errorf(ErrMsgOperationNormalizationFailed, shared.Report)
+	}
 
 	state := shared.Validation.Validate(shared.Doc, r.definition, shared.Report)
 	if state != astvalidation.Valid {
-		return shared.Report
+		return fmt.Errorf(ErrMsgOperationValidationFailed, shared.Report)
 	}
 
 	preparedPlan := shared.Planner.Plan(shared.Doc, r.definition, operation.Name, shared.Report)
@@ -845,6 +848,9 @@ func (h *GraphQLHandler) preparePlan(operationHash uint64, requestOperationName
 		} else {
 			shared.Normalizer.NormalizeNamedOperation(shared.Doc, h.definition, requestOperationName, shared.Report)
 		}
+		if shared.Report.HasErrors() {
+			return nil, fmt.Errorf(ErrMsgOperationNormalizationFailed, shared.Report)
+		}
 
 		state := shared.Validation.Validate(shared.Doc, h.definition, shared.Report)
 		if state != astvalidation.Valid {

pkg/apihandler/errors.go

@@ -0,0 +1,7 @@
+package apihandler
+
+const (
+	ErrMsgOperationParseFailed         = "failed to parse operation: %w"
+	ErrMsgOperationNormalizationFailed = "failed to normalize operation: %w"
+	ErrMsgOperationValidationFailed    = "operation validation failed: %w"
+)

pkg/apihandler/internalapihandler.go

@@ -115,14 +115,17 @@ func (i *InternalBuilder) registerOperation(operation *wgpb.Operation) error {
 	shared.Parser.Parse(shared.Doc, shared.Report)
 
 	if shared.Report.HasErrors() {
-		return shared.Report
+		return fmt.Errorf(ErrMsgOperationParseFailed, shared.Report)
 	}
 
 	shared.Normalizer.NormalizeNamedOperation(shared.Doc, i.definition, []byte(operation.Name), shared.Report)
+	if shared.Report.HasErrors() {
+		return fmt.Errorf(ErrMsgOperationNormalizationFailed, shared.Report)
+	}
 
 	state := shared.Validation.Validate(shared.Doc, i.definition, shared.Report)
 	if state != astvalidation.Valid {
-		return shared.Report
+		return fmt.Errorf(ErrMsgOperationValidationFailed, shared.Report)
 	}
 
 	preparedPlan := shared.Planner.Plan(shared.Doc, i.definition, operation.Name, shared.Report)

pkg/node/node_test.go

@@ -18,7 +18,7 @@ import (
 
 	"github.com/gavv/httpexpect/v2"
 	"github.com/phayes/freeport"
-	"github.com/sebdah/goldie"
+	"github.com/sebdah/goldie/v2"
 	"github.com/stretchr/testify/assert"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
@@ -29,6 +29,8 @@ import (
 )
 
 func TestNode(t *testing.T) {
+	g := goldie.New(t, goldie.WithFixtureDir("fixtures"))
+
 	logger := logging.New(true, false, zapcore.DebugLevel)
 
 	userService := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -51,7 +53,7 @@ func TestNode(t *testing.T) {
 		assert.Equal(t, "67b77eab-d1a5-4cd8-b908-8443f24502b6", r.Header.Get("X-Request-Id"))
 		req, _ := httputil.DumpRequest(r, true)
 		_ = req
-		if bytes.Contains(req, []byte(`{"variables":{},"query":"query($first: Int){topProducts(first: $first){upc name price}}"}`)) {
+		if bytes.Contains(req, []byte(`{"variables":{"first":null},"query":"query($first: Int){topProducts(first: $first){upc name price}}"}`)) {
 			_, _ = w.Write([]byte(`{"data":{"topProducts":[{"upc":"1","name":"A","price":1},{"upc":"2","name":"B","price":2}]}}`))
 			return
 		}
@@ -161,54 +163,56 @@ func TestNode(t *testing.T) {
 	myReviews := withHeaders.GET("/operations/MyReviews").
 		WithQuery("unknown", 123).
 		Expect().Status(http.StatusOK).Body().Raw()
-	goldie.Assert(t, "get my reviews json rpc", prettyJSON(myReviews))
+	g.Assert(t, "get my reviews json rpc", prettyJSON(myReviews))
 
 	topProductsWithoutQuery := withHeaders.GET("/operations/TopProducts").
 		Expect().Status(http.StatusOK).Body().Raw()
-	goldie.Assert(t, "top products without query", prettyJSON(topProductsWithoutQuery))
+	g.Assert(t, "top products without query", prettyJSON(topProductsWithoutQuery))
 
 	topProductsWithQuery := withHeaders.GET("/operations/TopProducts").
 		WithQuery("first", 1).
 		WithQuery("unknown", 123).
 		Expect().Status(http.StatusOK).Body().Raw()
-	goldie.Assert(t, "top products with query", prettyJSON(topProductsWithQuery))
+	g.Assert(t, "top products with query", prettyJSON(topProductsWithQuery))
 
 	topProductsWithInvalidQuery := withHeaders.GET("/operations/TopProducts").
 		WithQuery("first", true).
 		Expect().Status(http.StatusBadRequest).Body().Raw()
-	goldie.Assert(t, "top products with invalid query", prettyJSON(topProductsWithInvalidQuery))
+	g.Assert(t, "top products with invalid query", prettyJSON(topProductsWithInvalidQuery))
 
 	topProductsWithQueryAsWgVariables := withHeaders.GET("/operations/TopProducts").
 		WithQuery("wg_variables", `{"first":1}`).
 		Expect().Status(http.StatusOK).Body().Raw()
-	goldie.Assert(t, "top products with query as wg variables", prettyJSON(topProductsWithQueryAsWgVariables))
+	g.Assert(t, "top products with query as wg variables", prettyJSON(topProductsWithQueryAsWgVariables))
 
 	topProductsWithInvalidQueryAsWgVariables := withHeaders.GET("/operations/TopProducts").
 		WithQuery("wg_variables", `{"first":true}`).
 		Expect().Status(http.StatusBadRequest).Body().Raw()
-	goldie.Assert(t, "top products with invalid query as wg variables", prettyJSON(topProductsWithInvalidQueryAsWgVariables))
+	g.Assert(t, "top products with invalid query as wg variables", prettyJSON(topProductsWithInvalidQueryAsWgVariables))
 
 	request := GraphQLRequest{
 		OperationName: "MyReviews",
 		Query:         federationTestQuery,
 	}
 
 	actual := withHeaders.POST("/graphql").WithJSON(request).Expect().Status(http.StatusOK).Body().Raw()
-	goldie.Assert(t, "post my reviews graphql", prettyJSON(actual))
+	g.Assert(t, "post my reviews graphql", prettyJSON(actual))
 
 	withHeaders.GET("/graphql").Expect().Status(http.StatusOK).Text(
 		httpexpect.ContentOpts{MediaType: "text/html"})
 }
 
 func TestInMemoryCache(t *testing.T) {
+	g := goldie.New(t, goldie.WithFixtureDir("fixtures"))
+
 	logger := logging.New(true, false, zapcore.DebugLevel)
 
 	productService := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		data, err := io.ReadAll(r.Body)
 		if err != nil {
 			t.Fatal(err)
 		}
-		if bytes.Contains(data, []byte(`{"variables":{},"query":"query($first: Int){topProducts(first: $first){upc name price}}"}`)) {
+		if bytes.Contains(data, []byte(`{"variables":{"first":null},"query":"query($first: Int){topProducts(first: $first){upc name price}}"}`)) {
 			if _, err := io.WriteString(w, `{"data":{"topProducts":[{"upc":"1","name":"A","price":1},{"upc":"2","name":"B","price":2}]}}`); err != nil {
 				t.Fatal(err)
 			}
@@ -312,13 +316,13 @@ func TestInMemoryCache(t *testing.T) {
 	// Send a request to populate the cache
 	cold := withHeaders.GET("/operations/TopProducts").Expect()
 	cold.Status(http.StatusOK).Header(cacheHeaderName).Equal("MISS")
-	goldie.Assert(t, expectedDataName, prettyJSON(cold.Body().Raw()))
+	g.Assert(t, expectedDataName, prettyJSON(cold.Body().Raw()))
 
 	// Close the origin, so request can only be answered from the in-memory cache
 	productService.Close()
 	hot := withHeaders.GET("/operations/TopProducts").Expect()
 	hot.Status(http.StatusOK).Header(cacheHeaderName).Equal("HIT")
-	goldie.Assert(t, expectedDataName, prettyJSON(hot.Body().Raw()))
+	g.Assert(t, expectedDataName, prettyJSON(hot.Body().Raw()))
 }
 
 func TestWebHooks(t *testing.T) {