cache, serve & display more comprehensive RBF info

backend/src/api/rbf-cache.ts

@@ -1,31 +1,64 @@
+import { TransactionExtended } from "../mempool.interfaces";
+
 export interface CachedRbf {
   txid: string;
   expires: Date;
 }
 
+export interface CachedRbfs {
+  txids: string[];
+  expires: Date;
+}
+
 class RbfCache {
-  private cache: { [txid: string]: CachedRbf; } = {};
+  private replacedby: { [txid: string]: CachedRbf; } = {};
+  private replaces: { [txid: string]: CachedRbfs } = {};
+  private txs: { [txid: string]: TransactionExtended } = {};
 
   constructor() {
     setInterval(this.cleanup.bind(this), 1000 * 60 * 60);
   }
 
-  public add(replacedTxId: string, newTxId: string): void {
-    this.cache[replacedTxId] = {
-      expires: new Date(Date.now() + 1000 * 604800), // 1 week
+  public add(replacedTx: TransactionExtended, newTxId: string): void {
+    const expiry = new Date(Date.now() + 1000 * 604800); // 1 week
+    this.replacedby[replacedTx.txid] = {
+      expires: expiry,
       txid: newTxId,
     };
+    this.txs[replacedTx.txid] = replacedTx;
+    if (!this.replaces[newTxId]) {
+      this.replaces[newTxId] = {
+        txids: [],
+        expires: expiry,
+      };
+    }
+    this.replaces[newTxId].txids.push(replacedTx.txid);
+    this.replaces[newTxId].expires = expiry;
   }
 
-  public get(txId: string): CachedRbf | undefined {
-    return this.cache[txId];
+  public getReplacedBy(txId: string): CachedRbf | undefined {
+    return this.replacedby[txId];
+  }
+
+  public getReplaces(txId: string): CachedRbfs | undefined {
+    return this.replaces[txId];
+  }
+
+  public getTx(txId: string): TransactionExtended | undefined {
+    return this.txs[txId];
   }
 
   private cleanup(): void {
     const currentDate = new Date();
-    for (const c in this.cache) {
-      if (this.cache[c].expires < currentDate) {
-        delete this.cache[c];
+    for (const c in this.replacedby) {
+      if (this.replacedby[c].expires < currentDate) {
+        delete this.replacedby[c];
+        delete this.txs[c];
+      }
+    }
+    for (const c in this.replaces) {
+      if (this.replaces[c].expires < currentDate) {
+        delete this.replaces[c];
       }
     }
   }