Batch outspends requests

fixes #1902

backend/src/api/bitcoin/bitcoin-api-abstract-factory.ts

@@ -13,6 +13,7 @@ export interface AbstractBitcoinApi {
   $getAddressPrefix(prefix: string): string[];
   $sendRawTransaction(rawTransaction: string): Promise<string>;
   $getOutspends(txId: string): Promise<IEsploraApi.Outspend[]>;
+  $getBatchedOutspends(txId: string[]): Promise<IEsploraApi.Outspend[][]>;
 }
 export interface BitcoinRpcCredentials {
   host: string;

backend/src/api/bitcoin/bitcoin-api.ts

@@ -141,6 +141,15 @@ class BitcoinApi implements AbstractBitcoinApi {
     return outSpends;
   }
 
+  async $getBatchedOutspends(txId: string[]): Promise<IEsploraApi.Outspend[][]> {
+    const outspends: IEsploraApi.Outspend[][] = [];
+    for (const tx of txId) {
+      const outspend = await this.$getOutspends(tx);
+      outspends.push(outspend);
+    }
+    return outspends;
+  }
+
   $getEstimatedHashrate(blockHeight: number): Promise<number> {
     // 120 is the default block span in Core
     return this.bitcoindClient.getNetworkHashPs(120, blockHeight);

backend/src/api/bitcoin/esplora-api.ts

@@ -61,8 +61,18 @@ class ElectrsApi implements AbstractBitcoinApi {
     throw new Error('Method not implemented.');
   }
 
-  $getOutspends(): Promise<IEsploraApi.Outspend[]> {
-    throw new Error('Method not implemented.');
+  $getOutspends(txId: string): Promise<IEsploraApi.Outspend[]> {
+    return axios.get<IEsploraApi.Outspend[]>(config.ESPLORA.REST_API_URL + '/tx/' + txId, this.axiosConfig)
+      .then((response) => response.data);
+  }
+
+  async $getBatchedOutspends(txId: string[]): Promise<IEsploraApi.Outspend[][]> {
+    const outspends: IEsploraApi.Outspend[][] = [];
+    for (const tx of txId) {
+      const outspend = await this.$getOutspends(tx);
+      outspends.push(outspend);
+    }
+    return outspends;
   }
 }