The backend api calls in the frontend should only happen through services

We expect all the backend API calls should happen through a service but currently there exist multiple directives that make http request. This issue focuses on refactoring directives such that they don’t make any HTTP requests.

Tips on how to resolve this issue: Assume a directive makes an http call to URL \someurl\andsomethingmore

• Check whether there exists any service which makes this calls, if yes then use the existing service in the directive
  • You can do this through git grep "someurl\and" and check for a service.ts file.
• If there isn’t any existing service that makes this call then create a new *-backend-api.service.ts file and use that service in the directive. The new service should be written in angular, please follow this doc that describes how to write such service.

Please contact @srijanreddy98 if you have any questions about this issue.

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PR’s for reference: #8061

To be assigned to a file or for any queries, comment on the thread and tag @DubeySandeep

The files listed below should be refactored with for the expected behavior:

• core/templates/services/translation-file-hash-loader-backend-api.service.ts @tpapesh
• core/templates/pages/exploration-editor-page/editor-tab/templates/modal-templates/teach-oppia-modal.controller.ts
• core/templates/components/entity-creation-services/story-creation.service.ts

Note: For a guide on how to access Oppia’s webpages, see this.

[JeeveshGarg]

Okay, @mridul-netizen please assign me story-creation.service.ts Thanks.

[DubeySandeep]

@MohdImran001 I’ve assigned you to extensions/interactions/EndExploration/directives/oppia-interactive-end-exploration.directive.ts, you can use the existing ExplorationSummaryBackendApiService.loadPublicAndPrivateExplorationSummaries function instead of creating a new backend API service. Let me know if you need any help! 😃

@jay24rajput Welcome to Oppia! I’ve assigned you to core/templates/pages/preferences-page/preferences-page.component.ts, you can create a function in the existing UserBackendApiService (instead of creating a new file). Let me know if you need any help! 😃 [I found that core/templates/dev/head/pages/creator-dashboard-page/creator-dashboard-page.controller.ts is already resolved so assigned you to another part of this issue, I hope that’s fine!]