Cypress push value in json array

I would like to compile a list and push them into a json array in Cypress.

This is what the json out put is supposed to look like:

[
  {
    "role": "Administrator",
    "scenarios": [
      "clients_a",
      "clients_d",
      "clients_f",
      ....
    ]
  }
]

This is my code so far:

const permission_list = require('../../fixtures/permissions/permissions_admin.json')
const test_plan = 'cypress/fixtures/permissions/test_plan_admin.json'
const role = 'Administrator'

describe('Test plan creator for Administrator', () => {
    it('create a test plan', () => {
        //prepare the json array
        cy.writeFile(test_plan, [{role: role,scenarios: []}])

        cy.get(permission_list[0].granted_permissions).then((list) => {
            if (Cypress.$.inArray('clients', list) != -1) {
                cy.readFile(test_plan).then((scenarios) => {
                    scenarios.push('clients_a') // this is where I make a mistake I suppose
                    // write the merged list
                    cy.writeFile(test_plan, scenarios)
                })
            }
            ///added to handle case "clients" was not found in Array
            else {
            }
        })
    })
})

And this is the output of my code:

[
  {
    "role": "Administrator",
    "scenarios": []
  },
  "clients_a" <-- should be inside the list behind "scenarios"
]

So it's close but no cigar. How can I push the value "clients_a" into the list of "scenarios"?

The approach I would take is do everything in memory and only write the finished list once at the end.

There would be a slight speed up doing that, but main advantage is you don't need to worry about appending.

const permission_list = require('../../fixtures/permissions/permissions_admin.json')
const test-plan-file-path = 'cypress/fixtures/permissions/test_plan_admin.json'
const role = 'Administrator'

describe('Test plan creator for Administrator', () => {
  it('create a test plan', () => {

    //prepare the json array
    const scenarios = []

    cy.get(permission_list[0].granted_permissions).then((list) => {
      if (Cypress.$.inArray('clients', list) != -1) {
        scenarios.push('clients_a') 
      }
    })

    // write the result
    const plan = [{ role, scenarios}]
    cy.writeFile(test-plan-file-path, plan)     
  })
})

There's something else strange here, it looks like you push multiple items in a loop, but there is no loop here. Would need to see more of the app to suggest how to fix that.

You can do something like this. You have to create a structure inside the JSON file. Using the flag: a+ you can append texts at the end of file instead of overwriting it.

describe('Test plan creator for Administrator', () => {
  it('create a test plan', () => {

    //prepare the json array
    cy.writeFile(test_plan, '[{role: role,scenarios: [')

    cy.get(permission_list[0].granted_permissions).then((list) => {
      if (Cypress.$.inArray('clients', list) != -1) {
        cy.writeFile(test_plan, 'clients_a', {flag: 'a+'})
      }
    })

    cy.writeFile(test_plan, ']}]', {flag: 'a+'}) //complete the structure with closing brackets
  })
})

If you want to push multiple client ids, this is how I do it

const permission_list = require('../../fixtures/permissions/permissions_admin.json')
const test_plan = 'cypress/fixtures/permissions/test_plan_admin.json'
const role = 'Administrator'

describe('Test plan creator for Administrator', () => {

  before(() => {
    cy.writeFile(test_plan, [{role: role, scenarios: []}])
  })

  it('create a test plan', () => {

    cy.fixture('test_plan_admin.json').then(plan => {

      const list = permission_list[0].granted_permissions
      if (list.includes('clients')) {
        plan.scenarios.push('clients_a') 
      }

      cy.writeFile(test_plan, plan)     
    })
  })

  it('another client', () => {

    cy.fixture('test_plan_admin.json').then(plan => {

      const list = permission_list[0].granted_permissions
      if (list.includes('clients')) {
        plan.scenarios.push('clients_a') 
      }

      cy.writeFile(test_plan, plan)     
    })
  })

})