lib/instrumentation/modules/graphql.js

/*
 * Copyright Elasticsearch B.V. and other contributors where applicable.
 * Licensed under the BSD 2-Clause License; you may not use this file except in
 * compliance with the BSD 2-Clause License.
 */

'use strict';

var semver = require('semver');
var clone = require('shallow-clone-shim');

var getPathFromRequest = require('../express-utils').getPathFromRequest;

module.exports = function (graphql, agent, { version, enabled }) {
  if (!enabled) return graphql;
  if (
    !semver.satisfies(version, '>=0.7.0 <17') ||
    !graphql.Kind ||
    typeof graphql.Source !== 'function' ||
    typeof graphql.parse !== 'function' ||
    typeof graphql.validate !== 'function' ||
    typeof graphql.execute !== 'function'
  ) {
    agent.logger.debug(
      'graphql version %s not supported - aborting...',
      version,
    );
    return graphql;
  }

  // Over the many versions the `graphql()` and `execute()` functions have
  // changed in what arguments they accept:
  // - Initially they only supported positional arguments:
  //      function graphql(schema, requestString, rootValue, contextValue, variableValues, operationName)
  // - Starting in v0.10.0 (in #356), they started accepting a second form where
  //   all fields were passed in an object as the first argument:
  //      function graphql(argsOrSchema, source, rootValue, contextValue, variableValues, operationName, fieldResolver)
  //   and `arguments.length === 1` was used as the test to determine which.
  // - Starting in v16 (in #2904), they dropped positional arguments:
  //      function graphql(args)
  const onlySupportsPositionalArgs = semver.lt(version, '0.10.0');
  const onlySupportsSingleArg = semver.gte(version, '16.0.0');

  const ins = agent._instrumentation;

  return clone({}, graphql, {
    graphql(descriptor) {
      const getter = descriptor.get;
      if (getter) {
        descriptor.get = function get() {
          return wrapGraphql(getter());
        };
      }
      return descriptor;
    },
    execute(descriptor) {
      const getter = descriptor.get;
      if (getter) {
        descriptor.get = function get() {
          return wrapExecute(getter());
        };
      }
      return descriptor;
    },
  });

  function wrapGraphql(orig) {
    return function wrappedGraphql(args) {
      agent.logger.debug('intercepted call to graphql.graphql');
      const span = ins.createSpan(
        'GraphQL: Unknown Query',
        'db',
        'graphql',
        'execute',
      );
      if (!span) {
        return orig.apply(this, arguments);
      }

      let schema;
      let source;
      let operationName;
      const singleArgForm =
        onlySupportsSingleArg ||
        (!onlySupportsPositionalArgs && arguments.length === 1);
      if (singleArgForm) {
        schema = args.schema;
        source = args.source;
        operationName = args.operationName;
      } else {
        schema = arguments[0];
        source = arguments[1];
        operationName = arguments[5];
      }

      const sourceObj =
        typeof source === 'string'
          ? new graphql.Source(source || '', 'GraphQL request')
          : source;
      if (sourceObj) {
        var documentAST;

        try {
          documentAST = graphql.parse(sourceObj);
        } catch (syntaxError) {
          agent.logger.debug(
            'graphql.parse(source) failed - skipping graphql query extraction',
          );
        }

        if (documentAST) {
          var validationErrors = graphql.validate(schema, documentAST);
          if (validationErrors && validationErrors.length === 0) {
            var queries = extractDetails(documentAST, operationName).queries;
            if (queries.length > 0)
              span.name = 'GraphQL: ' + queries.join(', ');
          }
        }
      } else {
        agent.logger.debug(
          'graphql.Source(query) failed - skipping graphql query extraction',
        );
      }

      const spanRunContext = ins.currRunContext().enterSpan(span);
      const p = ins.withRunContext(spanRunContext, orig, this, ...arguments);
      p.then(function () {
        span.end();
      });
      return p;
    };
  }

  function wrapExecute(orig) {
    return function wrappedExecute(args) {
      agent.logger.debug('intercepted call to graphql.execute');
      const span = ins.createSpan(
        'GraphQL: Unknown Query',
        'db',
        'graphql',
        'execute',
      );
      if (!span) {
        agent.logger.debug(
          'no active transaction found - skipping graphql tracing',
        );
        return orig.apply(this, arguments);
      }

      let document;
      let operationName;
      const singleArgForm =
        onlySupportsSingleArg ||
        (!onlySupportsPositionalArgs && arguments.length === 1);
      if (singleArgForm) {
        document = args.document;
        operationName = args.operationName;
      } else {
        document = arguments[1];
        operationName = arguments[5];
      }

      var details = extractDetails(document, operationName);
      var queries = details.queries;
      operationName =
        operationName ||
        (details.operation &&
          details.operation.name &&
          details.operation.name.value);
      if (queries.length > 0) {
        span.name =
          'GraphQL: ' +
          (operationName ? operationName + ' ' : '') +
          queries.join(', ');
      }

      // `_graphqlRoute` is a boolean, set in instrumentations of other modules
      // that specify 'graphql' in peerDependencies (e.g. '@apollo/server') to
      // indicate that this transaction is for a GraphQL request.
      const trans = span.transaction;
      if (trans._graphqlRoute) {
        var name =
          queries.length > 0 ? queries.join(', ') : 'Unknown GraphQL query';
        if (trans.req) var path = getPathFromRequest(trans.req, true);
        var defaultName = name;
        defaultName = path ? defaultName + ' (' + path + ')' : defaultName;
        defaultName = operationName
          ? operationName + ' ' + defaultName
          : defaultName;
        trans.setDefaultName(defaultName);
        trans.type = 'graphql';
      }

      const spanRunContext = ins.currRunContext().enterSpan(span);
      const p = ins.withRunContext(spanRunContext, orig, this, ...arguments);
      if (typeof p.then === 'function') {
        p.then(function () {
          span.end();
        });
      } else {
        span.end();
      }
      return p;
    };
  }

  function extractDetails(document, operationName) {
    var queries = [];
    var operation;

    if (document && Array.isArray(document.definitions)) {
      document.definitions.some(function (definition) {
        if (
          !definition ||
          definition.kind !== graphql.Kind.OPERATION_DEFINITION
        )
          return false;
        if (!operationName && operation) return false;
        if (
          !operationName ||
          (definition.name && definition.name.value === operationName)
        ) {
          operation = definition;
          return true;
        }
        return false;
      });

      var selections =
        operation &&
        operation.selectionSet &&
        operation.selectionSet.selections;
      if (selections && Array.isArray(selections)) {
        for (const selection of selections) {
          const kind = selection.name && selection.name.kind;
          if (kind === graphql.Kind.NAME) {
            const queryName = selection.name.value;
            if (queryName) queries.push(queryName);
          }
        }

        queries = queries.sort(function (a, b) {
          if (a > b) return 1;
          else if (a < b) return -1;
          return 0;
        });
      }
    } else {
      agent.logger.debug(
        'unexpected document format - skipping graphql query extraction',
      );
    }

    return { queries, operation };
  }
};