1 files changed, 339 insertions, 0 deletions
diff --git a/vendor/github.com/graph-gophers/graphql-go/graphql.go b/vendor/github.com/graph-gophers/graphql-go/graphql.go
new file mode 100644
index 00000000..76a6434d
--- /dev/null
+++ b/vendor/github.com/graph-gophers/graphql-go/graphql.go
@@ -0,0 +1,339 @@
+package graphql
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"github.com/graph-gophers/graphql-go/errors"
+	"github.com/graph-gophers/graphql-go/internal/common"
+	"github.com/graph-gophers/graphql-go/internal/exec"
+	"github.com/graph-gophers/graphql-go/internal/exec/resolvable"
+	"github.com/graph-gophers/graphql-go/internal/exec/selected"
+	"github.com/graph-gophers/graphql-go/internal/query"
+	"github.com/graph-gophers/graphql-go/internal/schema"
+	"github.com/graph-gophers/graphql-go/internal/validation"
+	"github.com/graph-gophers/graphql-go/introspection"
+	"github.com/graph-gophers/graphql-go/log"
+	"github.com/graph-gophers/graphql-go/trace"
+	"github.com/graph-gophers/graphql-go/types"
+)
+
+// ParseSchema parses a GraphQL schema and attaches the given root resolver. It returns an error if
+// the Go type signature of the resolvers does not match the schema. If nil is passed as the
+// resolver, then the schema can not be executed, but it may be inspected (e.g. with ToJSON).
+func ParseSchema(schemaString string, resolver interface{}, opts ...SchemaOpt) (*Schema, error) {
+	s := &Schema{
+		schema:         schema.New(),
+		maxParallelism: 10,
+		tracer:         trace.OpenTracingTracer{},
+		logger:         &log.DefaultLogger{},
+		panicHandler:   &errors.DefaultPanicHandler{},
+	}
+	for _, opt := range opts {
+		opt(s)
+	}
+
+	if s.validationTracer == nil {
+		if tracer, ok := s.tracer.(trace.ValidationTracerContext); ok {
+			s.validationTracer = tracer
+		} else {
+			s.validationTracer = &validationBridgingTracer{tracer: trace.NoopValidationTracer{}}
+		}
+	}
+
+	if err := schema.Parse(s.schema, schemaString, s.useStringDescriptions); err != nil {
+		return nil, err
+	}
+	if err := s.validateSchema(); err != nil {
+		return nil, err
+	}
+
+	r, err := resolvable.ApplyResolver(s.schema, resolver)
+	if err != nil {
+		return nil, err
+	}
+	s.res = r
+
+	return s, nil
+}
+
+// MustParseSchema calls ParseSchema and panics on error.
+func MustParseSchema(schemaString string, resolver interface{}, opts ...SchemaOpt) *Schema {
+	s, err := ParseSchema(schemaString, resolver, opts...)
+	if err != nil {
+		panic(err)
+	}
+	return s
+}
+
+// Schema represents a GraphQL schema with an optional resolver.
+type Schema struct {
+	schema *types.Schema
+	res    *resolvable.Schema
+
+	maxDepth                 int
+	maxParallelism           int
+	tracer                   trace.Tracer
+	validationTracer         trace.ValidationTracerContext
+	logger                   log.Logger
+	panicHandler             errors.PanicHandler
+	useStringDescriptions    bool
+	disableIntrospection     bool
+	subscribeResolverTimeout time.Duration
+}
+
+func (s *Schema) ASTSchema() *types.Schema {
+	return s.schema
+}
+
+// SchemaOpt is an option to pass to ParseSchema or MustParseSchema.
+type SchemaOpt func(*Schema)
+
+// UseStringDescriptions enables the usage of double quoted and triple quoted
+// strings as descriptions as per the June 2018 spec
+// https://facebook.github.io/graphql/June2018/. When this is not enabled,
+// comments are parsed as descriptions instead.
+func UseStringDescriptions() SchemaOpt {
+	return func(s *Schema) {
+		s.useStringDescriptions = true
+	}
+}
+
+// UseFieldResolvers specifies whether to use struct field resolvers
+func UseFieldResolvers() SchemaOpt {
+	return func(s *Schema) {
+		s.schema.UseFieldResolvers = true
+	}
+}
+
+// MaxDepth specifies the maximum field nesting depth in a query. The default is 0 which disables max depth checking.
+func MaxDepth(n int) SchemaOpt {
+	return func(s *Schema) {
+		s.maxDepth = n
+	}
+}
+
+// MaxParallelism specifies the maximum number of resolvers per request allowed to run in parallel. The default is 10.
+func MaxParallelism(n int) SchemaOpt {
+	return func(s *Schema) {
+		s.maxParallelism = n
+	}
+}
+
+// Tracer is used to trace queries and fields. It defaults to trace.OpenTracingTracer.
+func Tracer(tracer trace.Tracer) SchemaOpt {
+	return func(s *Schema) {
+		s.tracer = tracer
+	}
+}
+
+// ValidationTracer is used to trace validation errors. It defaults to trace.NoopValidationTracer.
+// Deprecated: context is needed to support tracing correctly. Use a Tracer which implements trace.ValidationTracerContext.
+func ValidationTracer(tracer trace.ValidationTracer) SchemaOpt { //nolint:staticcheck
+	return func(s *Schema) {
+		s.validationTracer = &validationBridgingTracer{tracer: tracer}
+	}
+}
+
+// Logger is used to log panics during query execution. It defaults to exec.DefaultLogger.
+func Logger(logger log.Logger) SchemaOpt {
+	return func(s *Schema) {
+		s.logger = logger
+	}
+}
+
+// PanicHandler is used to customize the panic errors during query execution.
+// It defaults to errors.DefaultPanicHandler.
+func PanicHandler(panicHandler errors.PanicHandler) SchemaOpt {
+	return func(s *Schema) {
+		s.panicHandler = panicHandler
+	}
+}
+
+// DisableIntrospection disables introspection queries.
+func DisableIntrospection() SchemaOpt {
+	return func(s *Schema) {
+		s.disableIntrospection = true
+	}
+}
+
+// SubscribeResolverTimeout is an option to control the amount of time
+// we allow for a single subscribe message resolver to complete it's job
+// before it times out and returns an error to the subscriber.
+func SubscribeResolverTimeout(timeout time.Duration) SchemaOpt {
+	return func(s *Schema) {
+		s.subscribeResolverTimeout = timeout
+	}
+}
+
+// Response represents a typical response of a GraphQL server. It may be encoded to JSON directly or
+// it may be further processed to a custom response type, for example to include custom error data.
+// Errors are intentionally serialized first based on the advice in https://github.com/facebook/graphql/commit/7b40390d48680b15cb93e02d46ac5eb249689876#diff-757cea6edf0288677a9eea4cfc801d87R107
+type Response struct {
+	Errors     []*errors.QueryError   `json:"errors,omitempty"`
+	Data       json.RawMessage        `json:"data,omitempty"`
+	Extensions map[string]interface{} `json:"extensions,omitempty"`
+}
+
+// Validate validates the given query with the schema.
+func (s *Schema) Validate(queryString string) []*errors.QueryError {
+	return s.ValidateWithVariables(queryString, nil)
+}
+
+// ValidateWithVariables validates the given query with the schema and the input variables.
+func (s *Schema) ValidateWithVariables(queryString string, variables map[string]interface{}) []*errors.QueryError {
+	doc, qErr := query.Parse(queryString)
+	if qErr != nil {
+		return []*errors.QueryError{qErr}
+	}
+
+	return validation.Validate(s.schema, doc, variables, s.maxDepth)
+}
+
+// Exec executes the given query with the schema's resolver. It panics if the schema was created
+// without a resolver. If the context get cancelled, no further resolvers will be called and a
+// the context error will be returned as soon as possible (not immediately).
+func (s *Schema) Exec(ctx context.Context, queryString string, operationName string, variables map[string]interface{}) *Response {
+	if !s.res.Resolver.IsValid() {
+		panic("schema created without resolver, can not exec")
+	}
+	return s.exec(ctx, queryString, operationName, variables, s.res)
+}
+
+func (s *Schema) exec(ctx context.Context, queryString string, operationName string, variables map[string]interface{}, res *resolvable.Schema) *Response {
+	doc, qErr := query.Parse(queryString)
+	if qErr != nil {
+		return &Response{Errors: []*errors.QueryError{qErr}}
+	}
+
+	validationFinish := s.validationTracer.TraceValidation(ctx)
+	errs := validation.Validate(s.schema, doc, variables, s.maxDepth)
+	validationFinish(errs)
+	if len(errs) != 0 {
+		return &Response{Errors: errs}
+	}
+
+	op, err := getOperation(doc, operationName)
+	if err != nil {
+		return &Response{Errors: []*errors.QueryError{errors.Errorf("%s", err)}}
+	}
+
+	// If the optional "operationName" POST parameter is not provided then
+	// use the query's operation name for improved tracing.
+	if operationName == "" {
+		operationName = op.Name.Name
+	}
+
+	// Subscriptions are not valid in Exec. Use schema.Subscribe() instead.
+	if op.Type == query.Subscription {
+		return &Response{Errors: []*errors.QueryError{{Message: "graphql-ws protocol header is missing"}}}
+	}
+	if op.Type == query.Mutation {
+		if _, ok := s.schema.EntryPoints["mutation"]; !ok {
+			return &Response{Errors: []*errors.QueryError{{Message: "no mutations are offered by the schema"}}}
+		}
+	}
+
+	// Fill in variables with the defaults from the operation
+	if variables == nil {
+		variables = make(map[string]interface{}, len(op.Vars))
+	}
+	for _, v := range op.Vars {
+		if _, ok := variables[v.Name.Name]; !ok && v.Default != nil {
+			variables[v.Name.Name] = v.Default.Deserialize(nil)
+		}
+	}
+
+	r := &exec.Request{
+		Request: selected.Request{
+			Doc:                  doc,
+			Vars:                 variables,
+			Schema:               s.schema,
+			DisableIntrospection: s.disableIntrospection,
+		},
+		Limiter:      make(chan struct{}, s.maxParallelism),
+		Tracer:       s.tracer,
+		Logger:       s.logger,
+		PanicHandler: s.panicHandler,
+	}
+	varTypes := make(map[string]*introspection.Type)
+	for _, v := range op.Vars {
+		t, err := common.ResolveType(v.Type, s.schema.Resolve)
+		if err != nil {
+			return &Response{Errors: []*errors.QueryError{err}}
+		}
+		varTypes[v.Name.Name] = introspection.WrapType(t)
+	}
+	traceCtx, finish := s.tracer.TraceQuery(ctx, queryString, operationName, variables, varTypes)
+	data, errs := r.Execute(traceCtx, res, op)
+	finish(errs)
+
+	return &Response{
+		Data:   data,
+		Errors: errs,
+	}
+}
+
+func (s *Schema) validateSchema() error {
+	// https://graphql.github.io/graphql-spec/June2018/#sec-Root-Operation-Types
+	// > The query root operation type must be provided and must be an Object type.
+	if err := validateRootOp(s.schema, "query", true); err != nil {
+		return err
+	}
+	// > The mutation root operation type is optional; if it is not provided, the service does not support mutations.
+	// > If it is provided, it must be an Object type.
+	if err := validateRootOp(s.schema, "mutation", false); err != nil {
+		return err
+	}
+	// > Similarly, the subscription root operation type is also optional; if it is not provided, the service does not
+	// > support subscriptions. If it is provided, it must be an Object type.
+	if err := validateRootOp(s.schema, "subscription", false); err != nil {
+		return err
+	}
+	return nil
+}
+
+type validationBridgingTracer struct {
+	tracer trace.ValidationTracer //nolint:staticcheck
+}
+
+func (t *validationBridgingTracer) TraceValidation(context.Context) trace.TraceValidationFinishFunc {
+	return t.tracer.TraceValidation()
+}
+
+func validateRootOp(s *types.Schema, name string, mandatory bool) error {
+	t, ok := s.EntryPoints[name]
+	if !ok {
+		if mandatory {
+			return fmt.Errorf("root operation %q must be defined", name)
+		}
+		return nil
+	}
+	if t.Kind() != "OBJECT" {
+		return fmt.Errorf("root operation %q must be an OBJECT", name)
+	}
+	return nil
+}
+
+func getOperation(document *types.ExecutableDefinition, operationName string) (*types.OperationDefinition, error) {
+	if len(document.Operations) == 0 {
+		return nil, fmt.Errorf("no operations in query document")
+	}
+
+	if operationName == "" {
+		if len(document.Operations) > 1 {
+			return nil, fmt.Errorf("more than one operation in query document and no operation name given")
+		}
+		for _, op := range document.Operations {
+			return op, nil // return the one and only operation
+		}
+	}
+
+	op := document.Operations.Get(operationName)
+	if op == nil {
+		return nil, fmt.Errorf("no operation with name %q", operationName)
+	}
+	return op, nil
+}