lerna: complete refactor!

packages/roleypoly-server/services/discord/restFetcher.js

@@ -2,33 +2,71 @@
 import type { IFetcher } from './types'
 import type DiscordSvc from '../discord'
 import type ErisClient, { User, Member, Guild } from 'eris'
+import LRU from 'lru-cache'
+import logger from '../../logger'
+const log = logger(__filename)
 
 export default class BotFetcher implements IFetcher {
   ctx: DiscordSvc
   client: ErisClient
+  cache: LRU<string, Guild | Member | User>
+
   constructor (ctx: DiscordSvc) {
     this.ctx = ctx
     this.client = ctx.client
+    this.cache = new LRU({
+      max: 50,
+      maxAge: 1000 * 60 * 10
+    })
   }
 
   getUser = async (id: string): Promise<?User> => {
+    if (this.cache.has(`U:${id}`)) {
+      log.debug('user cache hit')
+      return this.cache.get(`U:${id}`)
+    }
+
+    log.debug('user cache miss')
+
     try {
-      return await this.client.getRESTUser(id)
+      const u = await this.client.getRESTUser(id)
+      this.cache.set(`U:${id}`, u)
+      return u
     } catch (e) {
       return null
     }
   }
   getMember = async (server: string, user: string): Promise<?Member> => {
+    if (this.cache.has(`M:${server}:${user}`)) {
+      log.debug('member cache hit')
+      return this.cache.get(`M:${server}:${user}`)
+    }
+
+    log.debug('member cache miss')
+
     try {
-      return await this.client.getRESTGuildMember(server, user)
+      const m = await this.client.getRESTGuildMember(server, user)
+      this.cache.set(`M:${server}:${user}`, m)
+      // $FlowFixMe
+      m.guild = await this.getGuild(server) // we have to prefill this for whatever reason
+      return m
     } catch (e) {
       return null
     }
   }
 
   getGuild = async (server: string): Promise<?Guild> => {
+    if (this.cache.has(`G:${server}`)) {
+      log.debug('guild cache hit')
+      return this.cache.get(`G:${server}`)
+    }
+
+    log.debug('guild cache miss')
+
     try {
-      return await this.client.getRESTGuild(server)
+      const g = await this.client.getRESTGuild(server)
+      this.cache.set(`G:${server}`, g)
+      return g
     } catch (e) {
       return null
     }