init

services/bloom.js

@@ -0,0 +1,83 @@
+import BloomFilter from 'bloomfilter.js'
+
+import { download } from '@/store/snark'
+
+class BloomService {
+  constructor({ amount, commitment, instanceName, fileName, fileFolder }) {
+    this.amount = amount
+    this.fileFolder = fileFolder
+    this.commitment = commitment
+    this.instanceName = instanceName
+    this.fileName = `${fileFolder}/${fileName}`
+
+    this.idb = window.$nuxt.$indexedDB
+  }
+
+  async downloadBloom() {
+    const cachedBloom = await download({
+      name: this.fileName,
+      contentType: 'string',
+      eventName: this.fileFolder
+    })
+
+    if (!cachedBloom) {
+      throw new Error('Cant download file')
+    }
+
+    return BloomFilter.deserialize(cachedBloom)
+  }
+
+  async getBloomFromDB() {
+    try {
+      const stringifyCachedBloom = await this.idb.getAll({
+        storeName: `stringify_bloom_${this.instanceName}`
+      })
+
+      if (!stringifyCachedBloom || !stringifyCachedBloom.length) {
+        return undefined
+      }
+
+      const [{ tree }] = stringifyCachedBloom
+
+      return BloomFilter.deserialize(tree)
+    } catch (err) {
+      return undefined
+    }
+  }
+
+  async getBloomFromCache() {
+    try {
+      const bloom = await this.downloadBloom()
+      await this.saveBloom({ bloom })
+
+      return bloom
+    } catch (err) {
+      return false
+    }
+  }
+
+  async checkBloom() {
+    let cachedBloom = await this.getBloomFromDB()
+    if (!cachedBloom) {
+      cachedBloom = await this.getBloomFromCache()
+    }
+    return cachedBloom.test(this.commitment)
+  }
+
+  async saveBloom({ bloom }) {
+    try {
+      await this.idb.putItem({
+        storeName: `stringify_bloom_${this.instanceName}`,
+        data: {
+          hashBloom: '1', // need for replace bloom
+          tree: bloom.serialize()
+        },
+        key: 'hashBloom'
+      })
+    } catch (err) {
+      console.error('saveBloom has error:', err.message)
+    }
+  }
+}
+
+export const bloomService = (payload) => new BloomService(payload)