Function visitSelectionSet

src/GraphQL/helpers/queryComplexity.js:10–67

(selectionSet, depth, visitedFragments)

  const { maxDepth: allowedMaxDepth, maxFields: allowedMaxFields } = limits;

  function visitSelectionSet(selectionSet, depth, visitedFragments) {
    if (!selectionSet) {
      return;
    }
    if (
      (allowedMaxFields !== undefined && allowedMaxFields !== -1 && totalFields > allowedMaxFields) ||
      (allowedMaxDepth !== undefined && allowedMaxDepth !== -1 && maxDepth > allowedMaxDepth)
    ) {
      return;
    }
    for (const selection of selectionSet.selections) {
      if (selection.kind === 'Field') {
        totalFields++;
        const newDepth = depth + 1;
        if (newDepth > maxDepth) {
          maxDepth = newDepth;
        }
        if (selection.selectionSet) {
          visitSelectionSet(selection.selectionSet, newDepth, visitedFragments);
        }
      } else if (selection.kind === 'InlineFragment') {
        visitSelectionSet(selection.selectionSet, depth, visitedFragments);
      } else if (selection.kind === 'FragmentSpread') {
        const name = selection.name.value;
        if (fragmentCache.has(name)) {
          const cached = fragmentCache.get(name);
          totalFields += cached.fields;
          const adjustedDepth = depth + cached.maxDepthDelta;
          if (adjustedDepth > maxDepth) {
            maxDepth = adjustedDepth;
          }
          continue;
        }
        if (visitedFragments.has(name)) {
          continue;
        }
        const fragment = fragments[name];
        if (fragment) {
          if (
            (allowedMaxFields !== undefined && allowedMaxFields !== -1 && totalFields > allowedMaxFields) ||
            (allowedMaxDepth !== undefined && allowedMaxDepth !== -1 && maxDepth > allowedMaxDepth)
          ) {
            continue;
          }
          visitedFragments.add(name);
          const savedFields = totalFields;
          const savedMaxDepth = maxDepth;
          maxDepth = depth;
          visitSelectionSet(fragment.selectionSet, depth, visitedFragments);
          const fieldsContribution = totalFields - savedFields;
          const maxDepthDelta = maxDepth - depth;
          fragmentCache.set(name, { fields: fieldsContribution, maxDepthDelta });
          maxDepth = Math.max(savedMaxDepth, maxDepth);
          visitedFragments.delete(name);
        }
      }
    }
  }