Method resolveNestedFields

query/outputnode_graphql.go:1016–1048

resolveNestedFields resolves fields which themselves don't have the @custom directive but their children might. queryUser { id classes { name @custom... } } In the example above, resolveNestedFields would be called on classes field and parentNodeHeads would be the list of head pointers

(childField gqlSchema.Field,
	parentNodeHeads []fastJsonNode, wg *sync.WaitGroup)

// In the example above, resolveNestedFields would be called on classes field and parentNodeHeads
// would be the list of head pointers for all the user fastJson nodes.
func (genc *graphQLEncoder) resolveNestedFields(childField gqlSchema.Field,
	parentNodeHeads []fastJsonNode, wg *sync.WaitGroup) {
	defer wg.Done() // signal when this goroutine finishes execution

	var childNodeHeads []fastJsonNode
	var parentNodeHeadAttr uint16
	if len(parentNodeHeads) > 0 {
		parentNodeHeadAttr = genc.getAttr(parentNodeHeads[0])
	}
	childFieldAttr := genc.idForAttr(childField.DgraphAlias())
	// iterate over all the parentNodeHeads and build the list of childNodeHeads for this childField
	for _, parentNodeHead := range parentNodeHeads {
		// iterate over all the siblings of this parentNodeHead which have the same attr as this
		for parentNode := parentNodeHead; parentNode != nil && genc.getAttr(
			parentNode) == parentNodeHeadAttr; parentNode = parentNode.next {
			// find the first child node which has data for childField
			fj := genc.children(parentNode)
			for ; fj != nil && genc.getAttr(fj) != childFieldAttr; fj = fj.next {
				// do nothing, just keep skipping unnecessary data
			}
			if fj != nil {
				// we found the first node that has data for childField,
				// add that node to the list of childNodeHeads
				childNodeHeads = append(childNodeHeads, fj)
			}
		}
	}
	// if we found some data for the child field, then only we need to
	// resolve the custom fields in the selection set of childField
	if len(childNodeHeads) > 0 {
		genc.resolveCustomFields(childField.SelectionSet(), childNodeHeads)
	}
}

// completeRootAggregateQuery builds GraphQL JSON for aggregate queries at root.
// Root aggregate queries return a single object of type `TypeAggregateResult` which contains the