mia-platform / crud-service / 9127173903

/*

 * Copyright 2023 Mia s.r.l.

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

'use strict'

const fp = require('fastify-plugin')

const fastifyEnv = require('@fastify/env')

const fastifyMultipart = require('@fastify/multipart')

const ajvFormats = require('ajv-formats')

const { unset: lunset } = require('lodash')

const { readdirSync } = require('fs')

const { join } = require('path')

const { ObjectId } = require('mongodb')

const { JSONPath } = require('jsonpath-plus')

const myPackage = require('./package')

const fastifyEnvSchema = require('./envSchema')

const httpInterface = require('./lib/httpInterface')

const loadModels = require('./lib/loadModels')

const joinPlugin = require('./lib/joinPlugin')

const { castCollectionId } = require('./lib/pkFactories')

const {

  SCHEMA_CUSTOM_KEYWORDS,

  SETCMD,

  PUSHCMD,

  PULLCMD,

  UNSETCMD,

  ADDTOSETCMD,

} = require('./lib/consts')

const { registerMongoInstances } = require('./lib/mongo/mongo-plugin')

const { getAjvResponseValidationFunction } = require('./lib/validatorGetters')

const { pointerSeparator } = require('./lib/JSONPath.utils')

const { registerHelperRoutes } = require('./lib/helpersRoutes')

async function registerCrud(fastify, { modelName, isView }) {

  fastify.log.trace({ modelName }, 'Registering CRUD')

  const model = fastify.models[modelName]

  const prefix = model.definition.endpointBasePath

  fastify.decorate('crudService', model.crudService)

  fastify.decorate('queryParser', model.queryParser)

  fastify.decorate('castResultsAsStream', model.castResultsAsStream)

  fastify.decorate('castItem', model.castItem)

  fastify.decorate('allFieldNames', model.allFieldNames)

  fastify.decorate('jsonSchemaGenerator', model.jsonSchemaGenerator)

  fastify.decorate('jsonSchemaGeneratorWithNested', model.jsonSchemaGeneratorWithNested)

  fastify.decorate('modelName', modelName)

  fastify.register(httpInterface, { prefix, registerGetters: true, registerSetters: !isView })

}

async function registerViewCrud(fastify, { modelName, lookups }) {

  fastify.log.trace({ modelName }, 'Registering View CRUD')

  const { definition, viewDependencies, crudService } = fastify.models[modelName]

  const prefix = definition.endpointBasePath

  fastify.decorate('crudService', viewDependencies.crudService)

  fastify.decorate('queryParser', viewDependencies.queryParser)

  fastify.decorate('castResultsAsStream', viewDependencies.castResultsAsStream)

  fastify.decorate('castItem', viewDependencies.castItem)

  fastify.decorate('allFieldNames', viewDependencies.allFieldNames)

  fastify.decorate('jsonSchemaGenerator', viewDependencies.jsonSchemaGenerator)

  fastify.decorate('jsonSchemaGeneratorWithNested', viewDependencies.jsonSchemaGenerator)

  fastify.decorate('modelName', modelName)

  // To allow writing views without having to rewrite all the logic of the HttpInterface,

  // it was decided to adapt the fields of the calls towards the view by converting them

  // to the fields of the underlying collection, thus hiding the complexity on the client

  // side while maintaining consistent interfaces.

  // This assumes that the key of the value is in the field "value" and should be made configurable.

  fastify.addHook('preHandler', (request, _reply, done) => {

    for (const { as, localField } of lookups) {

      if (request?.body?.[as]) {

        const lookupReference = request.body[as]

        delete request.body[as]

        request.body[localField] = mapLookupToObjectId(lookupReference)

      }

      for (const command of [SETCMD, UNSETCMD, PUSHCMD, PULLCMD, ADDTOSETCMD]) {

        if (request?.body?.[command]?.[as]) {

          const lookupReference = request.body[command][as]

          delete request.body[command][as]

          request.body[command][localField] = mapLookupToObjectId(lookupReference)

        }

      }

    }

    done()

  })

  // To obtain the updated object with a consistent interface after a patch,

  // it is necessary to retrieve the view object again before returning it to the client.

  fastify.addHook('preSerialization', async function preSerializer(request, _reply, payload) {

    const { _id } = payload

    if (request.method === 'PATCH' && _id) {

      const docId = this.castCollectionId(_id)

      // eslint-disable-next-line no-underscore-dangle

      const doc = await crudService._mongoCollection.findOne({ _id: docId })

      const response = this.castItem(doc)

      const validatePatch = getAjvResponseValidationFunction(request.routeSchema.response['200'])

      validatePatch(response)

      return response

    }

    return payload

  })

  fastify.register(httpInterface, { prefix, registerGetters: false, registerSetters: true })

}

function mapLookupToObjectId(reference) {

  // consider both one-to-one and one-to-many relationships

  if (Array.isArray(reference)) {

    return reference

      .filter(Boolean)

  }

}

async function registerViewCrudLookup(fastify, { modelName, lookupModel }) {

  fastify.log.trace({ modelName }, 'Registering ViewLookup CRUD')

  const {

    as: modelField,

  } = lookupModel.lookup

  const { definition } = fastify.models[modelName]

  const prefix = definition.endpointBasePath

  const lookupPrefix = join(prefix, 'lookup', modelField)

  fastify.decorate('crudService', lookupModel.crudService)

  fastify.decorate('queryParser', lookupModel.queryParser)

  fastify.decorate('castResultsAsStream', lookupModel.castResultsAsStream)

  fastify.decorate('castItem', lookupModel.castItem)

  fastify.decorate('allFieldNames', lookupModel.allFieldNames)

  fastify.decorate('jsonSchemaGenerator', lookupModel.jsonSchemaGenerator)

  fastify.decorate('jsonSchemaGeneratorWithNested', lookupModel.jsonSchemaGenerator)

  fastify.decorate('modelName', modelName)

  fastify.decorate('lookupProjection', lookupModel.parsedLookupProjection)

  fastify.register(httpInterface, {

    prefix: lookupPrefix,

    registerGetters: false,

    registerSetters: false,

    registerLookup: true,

  })

}

const registerDatabase = fp(registerMongoInstances, { decorators: { fastify: ['config'] } })

async function iterateOverCollectionDefinitionAndRegisterCruds(fastify) {

  fastify.decorate('castCollectionId', castCollectionId(fastify))

  fastify.decorate('userIdHeaderKey', fastify.config.USER_ID_HEADER_KEY.toLowerCase())

  fastify.decorate('validateOutput', fastify.config.ENABLE_STRICT_OUTPUT_VALIDATION)

  for (const [modelName, model] of Object.entries(fastify.models)) {

    const { isView, viewLookupsEnabled, viewDependencies } = model

      const lookups = viewDependencies.lookupsModels.map(({ lookup }) => lookup)

      fastify.register(registerViewCrud, {

        modelName,

        lookups,

      })

      for (const lookupModel of viewDependencies.lookupsModels) {

        fastify.register(registerViewCrudLookup, {

          modelName,

          lookupModel,

        })

      }

    }

    fastify.register(registerCrud, {

      modelName,

      isView,

    })

  }

}

const validCrudFolder = path => !['.', '..'].includes(path) && /\.js(on)?$/.test(path)

async function setupCruds(fastify) {

  const {

    COLLECTION_DEFINITION_FOLDER,

    VIEWS_DEFINITION_FOLDER,

    HELPERS_PREFIX,

  } = fastify.config

  const collections = readdirSync(COLLECTION_DEFINITION_FOLDER)

    .filter(validCrudFolder)

    .map(path => join(COLLECTION_DEFINITION_FOLDER, path))

    .map(require)

  fastify.decorate('collections', collections)

  const viewsFolder = VIEWS_DEFINITION_FOLDER

  if (viewsFolder) {

    const views = readdirSync(viewsFolder)

      .filter(validCrudFolder)

      .map(path => join(viewsFolder, path))

      .map(require)

    fastify.decorate('views', views)

  }

  if (collections.length > 0) {

    fastify

      .register(registerDatabase)

      .register(fp(loadModels))

      .register(iterateOverCollectionDefinitionAndRegisterCruds)

      .register(joinPlugin, { prefix: '/join' })

      .register(registerHelperRoutes, { prefix: HELPERS_PREFIX })

  }

}

/* =============================================================================== */

module.exports = async function plugin(fastify, opts) {

  await fastify

    .register(fastifyEnv, { schema: fastifyEnvSchema, data: opts })

  fastify.register(fastifyMultipart, {

    limits: {

      fields: 5,

      // Conversion Byte to Mb

      fileSize: fastify.config.MAX_MULTIPART_FILE_BYTES * 1000000,

      files: 1,

    },

  })

    .register(fp(setupCruds, { decorators: { fastify: ['config'] } }))

}

module.exports.options = {

  trustProxy: process.env.TRUSTED_PROXIES,

  // configure Fastify to employ Ajv Formats plugin,

  // which components were stripped from main Ajv implementation

  ajv: {

    customOptions: {

      validateFormats: true,

    },

    plugins: [ajvFormats],

  },

}

module.exports.swaggerDefinition = {

  openApiSpecification: process.env.OPEN_API_SPECIFICATION ?? 'swagger',

  info: {

    title: 'Crud Service',

    description: myPackage.description,

    version: myPackage.version,

  },

}

module.exports.transformSchemaForSwagger = ({ schema, url } = {}) => {

  // route with undefined schema will not be shown

  const {

    params = undefined,

    body = undefined,

    querystring = undefined,

    response = undefined,

    ...others

  } = schema

  const transformed = { ...others }

  if (params) { transformed.params = getTransformedSchema(params) }

  if (body) { transformed.body = getTransformedSchema(body) }

  if (querystring) { transformed.querystring = getTransformedSchema(querystring) }

  if (response) {

    transformed.response = {

      ...response,

    }

  }

  return { schema: transformed, url }

}

function getTransformedSchema(httpPartSchema) {

  const KEYS_TO_UNSET = [

    SCHEMA_CUSTOM_KEYWORDS.UNIQUE_OPERATION_ID,

    ...JSONPath({

      json: httpPartSchema,

      resultType: 'pointer',

      path: '$..[?(@ && @.type && Array.isArray(@.type))]',

    })

      .map(pointer => [

        `${pointer

          .slice(1)

          .replace(pointerSeparator, '.')}.type`,

        `${pointer

          .slice(1)

          .replace(pointerSeparator, '.')}.nullable`,

      ])

      .flat(),

  ]

  const response = httpPartSchema

  KEYS_TO_UNSET.forEach(keyToUnset => {

    lunset(response, `${keyToUnset}`)

  })

  return response

}

module.exports.getMetrics = function getMetrics(prometheusClient) {

  const collectionInvocation = new prometheusClient.Counter({

    name: 'mia_platform_crud_service_collection_invocation',

    help: 'Count collection invocation, not the document considered',

    labelNames: ['collection_name', 'type'],

  })

  return {

    collectionInvocation,

  }

}

// Note: when operating on a cluster with limited resources, due to fastify delay in registering,

// plugins we may miss the connectionCreated and connectionReady events thus we preferred using

// the isUp function that simply checks connection status is up and usable.

const isMongoUp = async(fastify) => fastify.collections.length === 0 || fastify.mongoDBCheckIsUp()

async function statusHandler(fastify) {

  const statusOK = await isMongoUp(fastify)

  const message = statusOK ? undefined : 'MongoDB status is unhealthy'

  return { statusOK, message }

}

async function readinessHandler(fastify) {

  const statusOK = await isMongoUp(fastify)

  return { statusOK }

}

module.exports.readinessHandler = readinessHandler

module.exports.checkUpHandler = statusHandler