Track and display purged transaction status

frontend/src/app/components/transaction/transaction.component.html

@@ -1,6 +1,10 @@
 <div class="container-xl">
 
   <div class="title-block">
+    <div *ngIf="isPurged" class="alert alert-mempool" role="alert">
+      <span i18n="transaction.purged|Purged from mempool">This transaction has been purged from our default sized 300MB mempool</span>
+    </div>
+
     <div *ngIf="rbfTransaction" class="alert alert-mempool" role="alert">
       <span i18n="transaction.rbf.replacement|RBF replacement">This transaction has been replaced by:</span>
       <app-truncate [text]="rbfTransaction.txid" [lastChars]="12" [link]="['/tx/' | relativeUrl, rbfTransaction.txid]"></app-truncate>

frontend/src/app/components/transaction/transaction.component.ts

@@ -43,6 +43,7 @@ export class TransactionComponent implements OnInit, AfterViewInit, OnDestroy {
   fetchRbfSubscription: Subscription;
   fetchCachedTxSubscription: Subscription;
   txReplacedSubscription: Subscription;
+  txPurgedSubscription: Subscription;
   blocksSubscription: Subscription;
   queryParamsSubscription: Subscription;
   urlFragmentSubscription: Subscription;
@@ -55,6 +56,7 @@ export class TransactionComponent implements OnInit, AfterViewInit, OnDestroy {
   fetchCpfp$ = new Subject<string>();
   fetchRbfHistory$ = new Subject<string>();
   fetchCachedTx$ = new Subject<string>();
+  isPurged: boolean = false;
   now = new Date().getTime();
   timeAvg$: Observable<number>;
   liquidUnblinding = new LiquidUnblinding();
@@ -359,6 +361,10 @@ export class TransactionComponent implements OnInit, AfterViewInit, OnDestroy {
       }
     });
 
+    this.txPurgedSubscription = this.stateService.txPurged$.subscribe((isPurged) => {
+      this.isPurged = isPurged;
+    });
+
     this.queryParamsSubscription = this.route.queryParams.subscribe((params) => {
       if (params.showFlow === 'false') {
         this.overrideFlowPreference = false;
@@ -494,6 +500,7 @@ export class TransactionComponent implements OnInit, AfterViewInit, OnDestroy {
     this.fetchRbfSubscription.unsubscribe();
     this.fetchCachedTxSubscription.unsubscribe();
     this.txReplacedSubscription.unsubscribe();
+    this.txPurgedSubscription.unsubscribe();
     this.blocksSubscription.unsubscribe();
     this.queryParamsSubscription.unsubscribe();
     this.flowPrefSubscription.unsubscribe();

frontend/src/app/interfaces/websocket.interface.ts

@@ -16,6 +16,7 @@ export interface WebsocketResponse {
   tx?: Transaction;
   rbfTransaction?: ReplacedTransaction;
   txReplaced?: ReplacedTransaction;
+  txPurged?: boolean;
   utxoSpent?: object;
   transactions?: TransactionStripped[];
   loadingIndicators?: ILoadingIndicators;

frontend/src/app/services/state.service.ts

@@ -94,6 +94,7 @@ export class StateService {
   mempoolBlockTransactions$ = new Subject<TransactionStripped[]>();
   mempoolBlockDelta$ = new Subject<MempoolBlockDelta>();
   txReplaced$ = new Subject<ReplacedTransaction>();
+  txPurged$ = new Subject<boolean>();
   utxoSpent$ = new Subject<object>();
   difficultyAdjustment$ = new ReplaySubject<DifficultyAdjustment>(1);
   mempoolTransactions$ = new Subject<Transaction>();

frontend/src/app/services/websocket.service.ts

@@ -261,6 +261,10 @@ export class WebsocketService {
       this.stateService.txReplaced$.next(response.txReplaced);
     }
 
+    if (response.txPurged != null) {
+      this.stateService.txPurged$.next(response.txPurged);
+    }
+
     if (response['mempool-blocks']) {
       this.stateService.mempoolBlocks$.next(response['mempool-blocks']);
     }