*# Bitergo Common Purpose of this package is to help to develop Bitergo webapps and reduce code duplication.

Installation

In order to install the bitergo-common can be used next command:

npm i bitergo-common

After that, BitergoCommonModule need to be imported to module, using forRoot static method:

import { NgModule } from '@angular/core';
...
import { BitergoCommonModule } from 'bitergo-common';

@NgModule({
  declarations: [...],
  imports: [
    ...,
    BitergoCommonModule.forRoot()
  ],
  providers: [..],
  bootstrap: [...]
})
export class AppModule { }

BitergoCommonModule forRoot static method has no any configuration input, for now.

Overview

The bitergo-common library includes 2 services and 1 pipe:

• HTMLTagService

Allows to append html tag/scripts with tiny amount of efforts in declarative

• ProviderService

Allows to append or remove html tag/scripts or run the actions, depends on boolean indicator, in concrete order with waiting until scripts will be loaded.

• SafePipe

Allows to use DomSanitizer in html template with specifying type of resource.

HTMLTagService

The service provides quick interface to append and remove html tags or scripts, with possibility to wait until they will be loaded.

Using service, can be called next public methods:

• append(input: HtmlAppendOptions): number | undefined
• appendAndLoad(options: HtmlAppendOptions): Promise<number | undefined>
• remove(id?: number): void

Methods append and appendAndLoad are doing almost the same, but second one is waiting until loading is finished and returns Promise.

Both appends html tag, and in case of success they return number - id of created HtmlElement inside the service.

Result id of append and appendAndLoad methods is NOT the same as id attribute of the HtmlElement.

Result id can be used ONLY for removing html element from DOM, using remove method.

As the input for the append methods, can be used HtmlAppendOptions interface:

interface HtmlAppendOptions {
  // name of tag to append
  element: keyof HTMLElementTagNameMap;
  // query to parent container, that will be used to append HTML tag
  // default: 'head'
  parentQuery?: string | typeof head | typeof body;
  // any HTML tag attributes, like className, src, or whatever
  attributes?: Record<string, string>;
  // whether need to append tag on server side too.
  allowInSSR?: boolean;
  // the same as 'style' attribute of the 'HTMLElement'
  style?: Partial<CSSStyleDeclaration>;
}

ProviderService

This service is using HTMLTagService to append/remove script/tag or run some action.

It can be done by some condition, in chainable way, with possibility to rebuild everything on some events.

It provides only one public method update with input of interface ProviderServiceOptions.

Service is suitable to use when exists next conditions:

• there is a need to append some scripts, sequentially and wait when every script is loaded;
• need to remove scripts from DOM when some condition is changed;
• need to run some action on different conditions changed;
• need to append/remove html tags depends on events or conditions;

The idea behind the service is next:

• input contains providers and events properties;
• events are rxjs Subject objects;
• providers are the set of actions (means any function), scripts or tags (further provider item);
• actions consists from onAllow and 'onDisallow' function;
• each provider item can have others sets of provider items (actions', scriptsortags`);
• generally it can be created tree with provider items;
• every provider item has isAllowedPredicate input function to determine current state;
• when update function executes and:

-isAllowedPredicate returns true (build process) - scripts or tags will be added to DOM, actions will call onAllow function;

-isAllowedPredicate returns false (destroy process) - scripts or tags will be removed from DOM, actions will call onDisallow function;

• before every build process will be executed destroy process;
• update will be executed (and destroy and build or destroy processes) everytime when event from events is fired;
• initially update will be executed once, no matter was any event fired or not;

Example

import { Component } from '@angular/core';
import { ProviderService } from 'bitergo-common';
import { CookieStatusNotificationService } from 'langs-cookie-consent';
import { providers } from './langs-cookie-consent.configuration';
import { MatomoTracker } from 'ngx-matomo';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {
  tagManagerScriptSource = 'https://www.googletagmanager.com/gtag/js?id=AW-12312321321';
  gtagScriptSource = '/assets/scripts/gtag.js';

  linkedInScriptSource = '/assets/scripts/linkedin.js';
  linkedInNoScriptSource = 'https://px.ads.linkedin.com/collect/?pid=32132132&fmt=gif';

  get isMatomoAllowed() {
    return this.cookieStatus.isProviderAllowed(providers.matomo);
  }

  get isGoogleAddsAllowed() {
    return this.cookieStatus.isProviderAllowed(providers.google_ads);
  };

  get isLinkedInAllowed() {
    return this.cookieStatus.isProviderAllowed(providers.linked_in);
  }

  constructor(
    private matomo: MatomoTracker,
    private providerService: ProviderService,
    private cookieStatus: CookieStatusNotificationService,
  ) {
    const { accepted, closed, rejected } = this.cookieStatus;

    this.providerService.update({
      isEnabledLogging: true,
      providers: [
        // first provider
        {
          isAllowedPredicate: () => this.isMatomoAllowed,
          actions: [{
            onAllow: () => this.matomo.rememberConsentGiven(),
            onDisallow: () => this.matomo.forgetConsentGiven(),
            tags: [{
              tagName: 'div',
              attributes: { 'className': 'test' }
            }]
          }]
        },
        // second provider
        {
          isAllowedPredicate: () => this.isGoogleAddsAllowed,
          scripts: [
            {
              src: this.tagManagerScriptSource,
              scripts: [{
                src: this.gtagScriptSource,
                removeQueries: [
                  'body script[src*=googleadservices]',
                  'body iframe[src*=doubleclick]'
                ]
              }]
            }
          ]
        },
        // third provider
        {
          isAllowedPredicate: () => this.isLinkedInAllowed,
          scripts: [
            {
              src: this.linkedInScriptSource,
              tags: [{
                tagName: 'img',
                attributes: {
                  src: this.linkedInNoScriptSource,
                  alt: 'None',
                  width: '1',
                  height: '1'
                },
                style: { display: 'none' },
                removeQueries: ['body script[src^="https://snap.licdn.com"]']
              }]
            }
          ]
        }
      ],
      events: [accepted, closed, rejected]
    })
  }
}

Example explanation

In example above we want to keep the state of scripts according with Cookie Consent banner.

In the banner we have three sliders: Matomo, Google Ads and Linked.

Depends on slider state - provider scripts/actions/tags should be added or removed. We want also update that state when Cookie Consent banner is accepted, closed or rejected.

In first scenario, if Matomo slider is toggled on (isMatomoAllowed getter):

1. onAllow: () => this.matomo.rememberConsentGiven() will be exectuted;
2. Then div tag with class test will be added;

In second scenario, if Google Adds slider is toggled on (isGoogleAddsAllowed getter):

1. Will be loaded script tagManagerScriptSource;
2. Then will be loaded gtagScriptSource script;

If Google Adds slider is toggled off - after removing gtagScriptSource script - will be removed all tags that matched queries:

removeQueries: [
  'body script[src*=googleadservices]',
  'body iframe[src*=doubleclick]'
]

The only one difference in the third scenario: after script is loaded - will be loaded tag image with attrbites and styles.

Count of nested provider items or amount of them is not limited.

Interfaces

import { Subject } from 'rxjs';

export interface ProviderNextOptions {
  scripts: ScriptOptions[];
  tags: TagOptions[];
  actions: ActionOptions[];
}

export interface ProviderRemoveTagOptions {
  removeQueries: string[];
}

export interface ProviderCommonTagOptions {
  parentQuery: string;
}

export interface ScriptOptions extends
  Partial<ProviderNextOptions>,
  Partial<ProviderRemoveTagOptions>,
  Partial<ProviderCommonTagOptions> {
  src: string;
}

export interface TagOptions extends
  Partial<ProviderNextOptions>,
  Partial<ProviderRemoveTagOptions>,
  Partial<ProviderCommonTagOptions> {
  tagName: keyof HTMLElementTagNameMap;
  attributes?: Record<string, string>;
  style?: Partial<CSSStyleDeclaration>;
}

export interface ActionOptions extends Partial<ProviderNextOptions> {
  onAllow: () => void;
  onDisallow: () => void;
}

export interface ProviderOptions extends Partial<ProviderNextOptions> {
  isAllowedPredicate: () => boolean;
}

export interface ProviderServiceOptions {
  providers: ProviderOptions[];
  events?: Subject<any>[];
  isEnabledLogging?: boolean;
}

export interface ProviderRemoveOptions {
  index?: string;
  element?: string;
  removeAction?: () => void;
  next: Partial<ProviderNextOptions> & Partial<ProviderRemoveTagOptions>;
}