mgs-graphql
Version:
The simple way to generates GraphQL schemas and Sequelize models from your models definition,microservice supported
199 lines (180 loc) • 7 kB
JavaScript
/**
* Created by yuyanq on 2018/9/13.
*/
const _ = require('lodash')
const graphql = require('graphql')
const RemoteSchema = require('../definition/RemoteSchema')
const helper = require('../utils/helper')
const invariant = require('../utils/invariant')
const relay = require('graphql-relay')
const _deadTimeLine = 3 * 60 * 1000 // 3 minute
const _numberOneSession = 20 // 每次清理的个数
const _mergeNQueryBulk = {}
function cleanNQuery () {
let counter = 0
const now = Date.now()
for (const qid in _mergeNQueryBulk) {
// const oneSession = _mergeNQueryBulk[qid]
if (_mergeNQueryBulk[qid].createTime && (now - _mergeNQueryBulk[qid].createTime > _deadTimeLine)) {
// console.log('cleanNQuery', now, _mergeNQueryBulk[qid].createTime)
delete _mergeNQueryBulk[qid]
counter++
if (counter >= _numberOneSession) { break }
}
}
}
async function mergeNQuery (context, edges, schema, getTargetBinding, info, toDbId) {
if (!edges || edges.length <= 1) {
return
}
const qid = context.qid
const findSelectionNode = (field, findName, isDeep) => {
// console.log('findSelectionNode field:', findName, graphql.print(field))
if (!field) { return null }
if (field.name && field.name.value === findName) { return field }
const selections = field.selectionSet && field.selectionSet.selections
if (isDeep && selections) {
for (let i = 0; i < selections.length; ++i) {
const node = findSelectionNode(selections[i], findName, isDeep)
if (node) { return node }
}
}
return null
}
// console.log('mergeNQuery', qid, schema.name, graphql.responsePathAsArray(info.path), edges, _mergeNQueryBulk)
const path = helper.contactPath(graphql.responsePathAsArray(info.path), 'edges', 'node') // 有点写死了
let node = null
// 处理Remote字段，生成N次查询的合并查询函数
const fieldsCfg = schema.config.fields
for (const key in fieldsCfg) {
if (!fieldsCfg.hasOwnProperty(key)) { continue }
const value = fieldsCfg[key]
if (!value || !(value.$type instanceof RemoteSchema)) continue
if (!node) { // lazy fetch node
const findNode = (info) => {
const {fieldNodes = []} = info
const nodeName = 'node'
let node = null
for (let i = 0; i < fieldNodes.length; ++i) {
node = findSelectionNode(fieldNodes[i], nodeName, true)
if (node) { break }
}
if (!node) {
// console.log(`${schema.name} plural query cant find node selection`)
}
return node
}
node = findNode(info)
if (!node) {
return
}
}
// console.log('mergeNQuery:createNQuery',key,value)
const createMergeNQuery = async(key, value) => {
const linkId = helper.formatLinkId(key)
invariant(linkId, `schema ${schema.name}: ${linkId} is null`)
const targetModelName = value['$type'].name
const apiName = helper.pluralQueryName(targetModelName)
const currPath = helper.contactPath(path, key)
const binding = getTargetBinding(targetModelName)
invariant(binding, `${targetModelName} remote binding not exist`)
if (!binding) {
// throw new Error(`${targetModelName} remote binding not exist`)
return
}
const findCurrNodeOnlyInSub = (parent, key) => {
let curr = null
const selections = parent.selectionSet && parent.selectionSet.selections
if (selections) {
for (let i = 0; i < selections.length; ++i) {
curr = findSelectionNode(selections[i], key, false)
if (curr) { return curr }
}
}
return curr
}
let currNode = findCurrNodeOnlyInSub(node, key)
if (!currNode) {
// console.warn('mergeNQuery:cant find curr node', key)
return
}
const id = 'id'
const isIncludeId = findCurrNodeOnlyInSub(currNode, id)
const currSelection = graphql.print(currNode)
currNode = _.trimStart(currSelection, key)
const firstBrace = currNode.indexOf('{')
if (firstBrace < 0) {
throw new Error('Invalid selection:', currNode)
}
if (!isIncludeId) { currNode = currNode.replace('{', `{ ${id}`) }
invariant(!_.isEmpty(currNode), `${schema.name} plural query cant find selection set in ${currSelection}`)
cleanNQuery()
if (!_mergeNQueryBulk[qid]) {
_mergeNQueryBulk[qid] = {createTime: Date.now()}
}
_mergeNQueryBulk[qid][currPath] = {}
const queryContext = _mergeNQueryBulk[qid][currPath]
// 找到所有sub id
// const subIds = _.map(edges, (v) => v.node[linkId])
const uniqueIds = (edges) => {
let ids = new Set()
edges.forEach(x => {
const v = x.node[linkId]
// console.log('linkId:',linkId,v,typeof v)
const type = typeof v
if (type === 'object') {
if (!_.isEmpty(v)) {
ids.add(v)
}
} else {
ids.add(v)
}
})
return [...ids]
}
const subIds = uniqueIds(edges)
if (binding.query[`get${targetModelName}sByIds`]) {
const res = await binding.query[`get${targetModelName}sByIds`]({ids: subIds.map(subId => relay.toGlobalId(targetModelName, subId))}, currNode, { context })
for (let node of res) {
queryContext[+toDbId(targetModelName, node.id)] = node
}
} else {
const selection = `{
edges{
node ${currNode}
}
}`
const res = await binding.query[apiName]({options: {where: {id: {in: subIds}}}}, selection, { context })
const nodeArr = res && res.edges
const length = nodeArr && nodeArr.length
for (let i = 0; i < length; ++i) {
const node = nodeArr[i].node
queryContext[+toDbId(targetModelName, node.id)] = node
}
}
queryContext.fn = (targetName, id, qContext) => {
id = toDbId(targetName, id)
try {
id = parseInt(id)
} catch (err) {
console.error(err.message)
return
}
// console.log('mergeNQuery:queryContext.fn:', id, qContext)
invariant(_.includes(subIds, id), `schema ${schema.name}'s remote ${targetName} query ${apiName}: id(${id}) must be included in ${subIds} `)
const res = qContext[id]
// delete qContext[id]
// if (Object.keys(qContext).length === 1) {
// invariant(qContext.hasOwnProperty('fn'), 'invalid queryContext', qContext)
// delete qContext['fn']
// }
return res
}
}
await createMergeNQuery(key, value)
}
}
module.exports = {
mergeNQueryBulk: _mergeNQueryBulk,
mergeNQuery
}