cy.session: Support IndexedDB

What would you like?

The new cy.session API currently doesn’t do anything with indexeddb. Is that likely to be supported in the future?

Why is this needed?

I’m testing an app that stores significants amounts of data in indexeddb to support offline use.

In the app, when a users choses to “Go Offline,” data is downloaded from the server to indexeddb. I would like to cache/restore that data with cy.session so that each tests for offline functionality doesn’t have to re-download that data.

Other

No response

[nicolassanmar]

I found a workaround to circumvent this: You can store the contents of the IndexedDB in localstorage in the setup() function, and then restore them on the validate() function. The exportIDB and importIDB functions use the utilities provided by this gist: https://gist.github.com/loilo/ed43739361ec718129a15ae5d531095b

Cypress.Commands.add(
  'exportIDB',
  (dbName) =>
    new Cypress.Promise(async (resolve) => {
      indexedDB.open(dbName).onsuccess = async (event) => {
        const db = (event.target as IDBOpenDBRequest).result
        const json = await exportToJson(db)
        console.log(json)
        localStorage.setItem(dbName, json)
        resolve(json)
      }
    })
)

Cypress.Commands.add(
  'importIDB',
  (dbName) =>
    new Cypress.Promise(async (resolve) => {
      const json = localStorage.getItem(dbName)
      console.log(json)
      if (!json) {
        resolve()
        return
      }
      indexedDB.open(dbName).onsuccess = async (event) => {
        const db = (event.target as IDBOpenDBRequest).result
        await clearDatabase(db)
        await importFromJson(db, json.toString())
        resolve()
      }
    })
)


Cypress.Commands.add('fn', () => {
  cy.session(
    () => {
      /*regular session setup */

      // export the data to localStorage, as session does not persist the IndexedDB
      cy.exportIDB()
    },
    {
      validate: () => {
        // import the data from localstorage to the indexedDB
        cy.importIDB()

        /* validate extra stuff */
      },
      // if you want this session to be cached only for a single file, remove the following option
      cacheAcrossSpecs: true,
    }
  )
})

[liquid1982]

This is brilliant! Will give it a try. Thanks for sharing!