Wrap graphql schema with enforced admin-only for mutations, timing etc

makeSchema.js

/* eslint-disable max-depth, no-console */
// TODO create adminSchema, leave adminQueries and mutations out of schema
// In the graphqlhandler, pass the right schema depending on isAdmin
import debug from 'debug'
import {get} from 'lodash'
import {GraphQLSchema, GraphQLObjectType} from 'graphql'
import ssrCache from 'stratokit/prerender/cache'
import {adminOnly} from './utils'
import {maskErrors} from 'graphql-errors'

import * as allQs from 'app/_server/graphql'

const dbg = debug('graphql')

const timings = {}
let lastDump = Date.now()
const checkDump = now => {
	if (now - lastDump > 10000) {
		lastDump = now
		console.log(
			'graphql timings',
			Object.entries(timings)
				.filter(o => o[1].count)
				.map(
					([name, m]) =>
						`${name}: ${m.count}x ${m.min}<=${Math.round(m.total / m.count)}<=${
							m.max
						} ms`
				)
		)
	}
}
const instrument = (q, name) => {
	const {resolve} = q
	const measurements = {
		min: 9999999,
		max: 0,
		count: 0,
		total: 0,
	}
	timings[name] = measurements
	return {
		...q,
		resolve: async (...args) => {
			const now = Date.now()
			let out, t
			try {
				out = await resolve(...args)
				t = Date.now() - now
				measurements.total += t
				measurements.count++
				if (t < measurements.min) measurements.min = t
				if (t > measurements.max) measurements.max = t
			} finally {
				dbg(`${name}: ${t >= 0 ? `${t}ms` : 'error'}`)
				if (t > 5000)
					console.error(
						`!!! query ${name} took ${t}ms`,
						JSON.stringify({
							v: get(args, '3.variableValues'),
							q: get(args, '3.operation.loc.source.body'),
						}).slice(0, 1000)
					)
				checkDump(now)
			}
			return out
		},
	}
}

const parts = Object.values(allQs)
const safeForSSR = {}
parts.forEach(p => {
	if (p.safeForSSR)
		p.safeForSSR.forEach(k => {
			safeForSSR[k] = true
		})
})

const alias = {
	query: 'queries',
	mutation: 'mutations',
	adminQuery: 'adminQueries',
	openMutation: 'openMutations',
}
const schemaTypes = {
	query: 'query',
	mutation: 'mutation',
	adminQuery: 'query',
	openMutation: 'mutation',
}
const isMutation = {
	mutation: true,
	openMutation: true,
}
const isAdminOnly = {
	mutation: true,
	adminQuery: true,
}
const types = Object.keys(schemaTypes)

const fieldsByType = {
	query: {},
	mutation: {},
}
for (const type of types) {
	const partsOfType = parts.map(p => p[type] || p[alias[type]]).filter(Boolean)
	if (!partsOfType.length) continue

	const fields = fieldsByType[schemaTypes[type]]

	for (const toAdd of partsOfType) {
		for (const k of Object.keys(toAdd)) {
			if (fields[k]) throw new Error(`Duplicate graphql endpoint ${k}`)
			fields[k] = instrument(toAdd[k], k)
			if (isMutation[type] && !safeForSSR[k]) {
				// Clear SSR cache on mutation
				const {resolve} = fields[k]
				fields[k].resolve = (...args) => {
					dbg('resetting SSR cache')
					ssrCache.reset()
					return resolve(...args)
				}
			}
			if (isAdminOnly[type]) {
				fields[k] = adminOnly(fields[k])
			}
		}
	}
}

const schema = {}
for (const type of Object.keys(fieldsByType)) {
	schema[type] = new GraphQLObjectType({
		name: type,
		fields: fieldsByType[type],
	})
}

const gqlSchema = new GraphQLSchema(schema)

// Hide error details from users
maskErrors(gqlSchema)

export default gqlSchema

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