Speed up unfurls by reusing puppeteer sessions

frontend/src/app/components/block/block-preview.component.ts

@@ -1,11 +1,153 @@
-import { Component } from '@angular/core';
-import { BlockComponent } from './block.component';
+import { Component, OnInit, OnDestroy, ViewChild, ElementRef } from '@angular/core';
+import { ActivatedRoute, ParamMap } from '@angular/router';
+import { ElectrsApiService } from '../../services/electrs-api.service';
+import { switchMap, tap, throttleTime, catchError, shareReplay, startWith, pairwise } from 'rxjs/operators';
+import { of, Subscription, asyncScheduler } from 'rxjs';
+import { StateService } from '../../services/state.service';
+import { SeoService } from 'src/app/services/seo.service';
+import { OpenGraphService } from 'src/app/services/opengraph.service';
+import { BlockExtended, TransactionStripped } from 'src/app/interfaces/node-api.interface';
+import { ApiService } from 'src/app/services/api.service';
+import { BlockOverviewGraphComponent } from 'src/app/components/block-overview-graph/block-overview-graph.component';
 
 @Component({
   selector: 'app-block-preview',
   templateUrl: './block-preview.component.html',
-  styleUrls: ['./block.component.scss', './block-preview.component.scss']
+  styleUrls: ['./block-preview.component.scss']
 })
-export class BlockPreviewComponent extends BlockComponent {
-  
+export class BlockPreviewComponent implements OnInit, OnDestroy {
+  network = '';
+  block: BlockExtended;
+  blockHeight: number;
+  blockHash: string;
+  isLoadingBlock = true;
+  strippedTransactions: TransactionStripped[];
+  overviewTransitionDirection: string;
+  isLoadingOverview = true;
+  error: any;
+  blockSubsidy: number;
+  fees: number;
+  overviewError: any = null;
+
+  overviewSubscription: Subscription;
+  networkChangedSubscription: Subscription;
+
+  @ViewChild('blockGraph') blockGraph: BlockOverviewGraphComponent;
+
+  constructor(
+    private route: ActivatedRoute,
+    private electrsApiService: ElectrsApiService,
+    public stateService: StateService,
+    private seoService: SeoService,
+    private openGraphService: OpenGraphService,
+    private apiService: ApiService
+  ) { }
+
+  ngOnInit() {
+    this.network = this.stateService.network;
+
+    const block$ = this.route.paramMap.pipe(
+      switchMap((params: ParamMap) => {
+        this.openGraphService.waitFor('block-viz');
+        this.openGraphService.waitFor('block-data');
+
+        const blockHash: string = params.get('id') || '';
+        this.block = undefined;
+        this.error = undefined;
+        this.fees = undefined;
+
+        let isBlockHeight = false;
+        if (/^[0-9]+$/.test(blockHash)) {
+          isBlockHeight = true;
+        } else {
+          this.blockHash = blockHash;
+        }
+
+        this.isLoadingBlock = true;
+        this.isLoadingOverview = true;
+
+        if (isBlockHeight) {
+          return this.electrsApiService.getBlockHashFromHeight$(parseInt(blockHash, 10))
+            .pipe(
+              switchMap((hash) => {
+                this.blockHash = hash;
+                return this.apiService.getBlock$(hash);
+              })
+            );
+        }
+        return this.apiService.getBlock$(blockHash);
+      }),
+      tap((block: BlockExtended) => {
+        this.block = block;
+        this.blockHeight = block.height;
+
+        this.seoService.setTitle($localize`:@@block.component.browser-title:Block ${block.height}:BLOCK_HEIGHT:: ${block.id}:BLOCK_ID:`);
+        this.isLoadingBlock = false;
+        this.setBlockSubsidy();
+        if (block?.extras?.reward !== undefined) {
+          this.fees = block.extras.reward / 100000000 - this.blockSubsidy;
+        }
+        this.stateService.markBlock$.next({ blockHeight: this.blockHeight });
+        this.isLoadingOverview = true;
+        this.overviewError = null;
+
+        this.openGraphService.waitOver('block-data');
+      }),
+      throttleTime(50, asyncScheduler, { leading: true, trailing: true }),
+      shareReplay(1)
+    );
+
+    this.overviewSubscription = block$.pipe(
+      startWith(null),
+      pairwise(),
+      switchMap(([prevBlock, block]) => this.apiService.getStrippedBlockTransactions$(block.id)
+        .pipe(
+          catchError((err) => {
+            this.overviewError = err;
+            return of([]);
+          }),
+          switchMap((transactions) => {
+            return of({ transactions, direction: 'down' });
+          })
+        )
+      ),
+    )
+    .subscribe(({transactions, direction}: {transactions: TransactionStripped[], direction: string}) => {
+      this.strippedTransactions = transactions;
+      this.isLoadingOverview = false;
+      if (this.blockGraph) {
+        this.blockGraph.destroy();
+        this.blockGraph.setup(this.strippedTransactions);
+      }
+    },
+    (error) => {
+      this.error = error;
+      this.isLoadingOverview = false;
+      if (this.blockGraph) {
+        this.blockGraph.destroy();
+      }
+    });
+
+    this.networkChangedSubscription = this.stateService.networkChanged$
+      .subscribe((network) => this.network = network);
+  }
+
+  ngOnDestroy() {
+    if (this.overviewSubscription) {
+      this.overviewSubscription.unsubscribe();
+    }
+    if (this.networkChangedSubscription) {
+      this.networkChangedSubscription.unsubscribe();
+    }
+  }
+
+  // TODO - Refactor this.fees/this.reward for liquid because it is not
+  // used anymore on Bitcoin networks (we use block.extras directly)
+  setBlockSubsidy() {
+    this.blockSubsidy = 0;
+  }
+
+  onGraphReady(): void {
+    this.openGraphService.waitOver('block-viz');
+  }
 }