Method rewriteAndExecute

graphql/resolve/query.go:90–145

(ctx context.Context, query schema.Query)

}

func (qr *queryResolver) rewriteAndExecute(ctx context.Context, query schema.Query) *Resolved {
	dgraphQueryDuration := &schema.LabeledOffsetDuration{Label: "query"}
	ext := &schema.Extensions{
		Tracing: &schema.Trace{
			Execution: &schema.ExecutionTrace{
				Resolvers: []*schema.ResolverTrace{
					{Dgraph: []*schema.LabeledOffsetDuration{dgraphQueryDuration}},
				},
			},
		},
	}

	emptyResult := func(err error) *Resolved {
		return &Resolved{
			// all the auto-generated queries are nullable, but users may define queries with
			// @custom(dql: ...) which may be non-nullable. So, we need to set the Data field
			// only if the query was nullable and keep it nil if it was non-nullable.
			// query.NullResponse() method handles that.
			Data:       query.NullResponse(),
			Field:      query,
			Err:        schema.SetPathIfEmpty(err, query.ResponseName()),
			Extensions: ext,
		}
	}

	dgQuery, vars, err := qr.queryRewriter.Rewrite(ctx, query)
	if err != nil {
		return emptyResult(schema.GQLWrapf(err, "couldn't rewrite query %s",
			query.ResponseName()))
	}
	qry := dgraph.AsString(dgQuery)

	queryTimer := newtimer(ctx, &dgraphQueryDuration.OffsetDuration)
	queryTimer.Start()
	resp, err := qr.executor.Execute(ctx,
		&dgoapi.Request{Query: qry, Vars: vars, ReadOnly: true}, query)
	queryTimer.Stop()

	if err != nil && !x.IsGqlErrorList(err) {
		err = schema.GQLWrapf(err, "Dgraph query failed")
		glog.Infof("Dgraph query execution failed : %s", err)
	}

	ext.TouchedUids = resp.GetMetrics().GetNumUids()[touchedUidsKey]
	if x.Config.GraphQL.GetBool("debug") {
		ext.DQLQuery = qry
	}
	resolved := &Resolved{
		Data:       resp.GetJson(),
		Field:      query,
		Err:        schema.SetPathIfEmpty(err, query.ResponseName()),
		Extensions: ext,
	}

	return resolved
}

func NewCustomDQLQueryResolver(ex DgraphExecutor) QueryResolver {