Implement Redis cache for block and mempool data

2023-05-12 16:29:45 -06:00
parent 8cfa4ef1a1
commit 5138f9a254
10 changed files with 358 additions and 9 deletions
--- a/backend/src/api/redis-cache.ts
+++ b/backend/src/api/redis-cache.ts
@@ -0,0 +1,140 @@
+import { createClient } from 'redis';
+import memPool from './mempool';
+import blocks from './blocks';
+import logger from '../logger';
+import config from '../config';
+import { BlockExtended, BlockSummary, TransactionExtended } from '../mempool.interfaces';
+
+class RedisCache {
+  private client;
+  private connected = false;
+
+  constructor() {
+    if (config.REDIS.ENABLED) {
+      const redisConfig = {
+        socket: {
+          path: config.REDIS.UNIX_SOCKET_PATH
+        }
+      };
+      this.client = createClient(redisConfig);
+      this.client.on('error', (e) => {
+        logger.err(`Error in Redis client: ${e instanceof Error ? e.message : e}`);
+      });
+      this.$ensureConnected();
+    }
+  }
+
+  private async $ensureConnected(): Promise<void> {
+    if (!this.connected && config.REDIS.ENABLED) {
+      return this.client.connect().then(() => {
+        this.connected = true;
+        logger.info(`Redis client connected`);
+      });
+    }
+  }
+
+  async $updateBlocks(blocks: BlockExtended[]) {
+    try {
+      await this.$ensureConnected();
+      await this.client.json.set('blocks', '$', blocks);
+    } catch (e) {
+      logger.warn(`Failed to update blocks in Redis cache: ${e instanceof Error ? e.message : e}`);
+    }
+  }
+
+  async $updateBlockSummaries(summaries: BlockSummary[]) {
+    try {
+      await this.$ensureConnected();
+      await this.client.json.set('block-summaries', '$', summaries);
+    } catch (e) {
+      logger.warn(`Failed to update blocks in Redis cache: ${e instanceof Error ? e.message : e}`);
+    }
+  }
+
+  async $addTransactions(newTransactions: TransactionExtended[]) {
+    try {
+      await this.$ensureConnected();
+      await Promise.all(newTransactions.map(tx => {
+        return this.client.json.set('tx:' + tx.txid, '$', tx);
+      }));
+    } catch (e) {
+      logger.warn(`Failed to add ${newTransactions.length} transactions to Redis cache: ${e instanceof Error ? e.message : e}`);
+    }
+  }
+
+  async $removeTransactions(transactions: string[]) {
+    try {
+      await this.$ensureConnected();
+      await Promise.all(transactions.map(txid => {
+        return this.client.del('tx:' + txid);
+      }));
+    } catch (e) {
+      logger.warn(`Failed to remove ${transactions.length} transactions from Redis cache: ${e instanceof Error ? e.message : e}`);
+    }
+  }
+
+  async $getBlocks(): Promise<BlockExtended[]> {
+    try {
+      await this.$ensureConnected();
+      return this.client.json.get('blocks');
+    } catch (e) {
+      logger.warn(`Failed to retrieve blocks from Redis cache: ${e instanceof Error ? e.message : e}`);
+      return [];
+    }
+  }
+
+  async $getBlockSummaries(): Promise<BlockSummary[]> {
+    try {
+      await this.$ensureConnected();
+      return this.client.json.get('block-summaries');
+    } catch (e) {
+      logger.warn(`Failed to retrieve blocks from Redis cache: ${e instanceof Error ? e.message : e}`);
+      return [];
+    }
+  }
+
+  async $getMempool(): Promise<{ [txid: string]: TransactionExtended }> {
+    const mempool = {};
+    try {
+      await this.$ensureConnected();
+      const keys = await this.client.keys('tx:*');
+      const promises: Promise<TransactionExtended[]>[] = [];
+      for (let i = 0; i < keys.length; i += 10000) {
+        const keySlice = keys.slice(i, i + 10000);
+        if (!keySlice.length) {
+          continue;
+        }
+        promises.push(this.client.json.mGet(keySlice, '$').then(chunk => {
+          for (const txs of chunk) {
+            for (const tx of txs) {
+              if (tx) {
+                mempool[tx.txid] = tx;
+              }
+            }
+          }
+        }));
+      }
+      await Promise.all(promises);
+    } catch (e) {
+      logger.warn(`Failed to retrieve mempool from Redis cache: ${e instanceof Error ? e.message : e}`);
+    }
+    return mempool;
+  }
+
+  async $loadCache() {
+    logger.info('Restoring mempool and blocks data from Redis cache');
+    // Load block data
+    const loadedBlocks = await this.$getBlocks();
+    const loadedBlockSummaries = await this.$getBlockSummaries();
+    // Load mempool
+    const loadedMempool = await this.$getMempool();
+
+    // Set loaded data
+    blocks.setBlocks(loadedBlocks || []);
+    blocks.setBlockSummaries(loadedBlockSummaries || []);
+    await memPool.$setMempool(loadedMempool);
+  }
+
+}
+
+export default new RedisCache();