How can I connect twice to db in Cypress tests?-CodePudding

I need to connect to my db (Postgres) twice during autotest - in the begining to truncate and in the ending to select new note from table.

I tried to do it by pg-promise, but in the second conneting it returns null or undefined (this error is showing after asserting expected and real results - "Target cannot be null or undefined.").

At that, if I don't execute the first connecting (for truncating), the second runs normally and returns new note from table.

Also, if I make Truncate after Select, it gives two different result, depending of is the table empty or not:

If it is empty, result is the same error. But if there is some record initially, all becomes ok and test finished without error.

This is how I make connecting and disconnecting to db:

const pgp = require('pg-promise')();
const postgresConfig = require(require('path').resolve('cypress.json'));

function dbConnection(query, userDefineConnection) {
  const db = pgp(userDefineConnection || postgresConfig.db);
  return db.any(query).finally(db.$pool.end)
  // return db.any(query).finally(pgp.end)
}

/**@type {Cypress.PluginConfig} */
module.exports = (on, config) => {
  on("task", {
    dbQuery: (query) => dbConnection(query.query, query.connection)
  });
}

And this is how I make requests to DB in test:

describe('example to-do app', () => {
  beforeEach(() => {
    cy.task('dbQuery', {'query': 'TRUNCATE TABLE auto_db.public.requests RESTART IDENTITY CASCADE'})
  })

  it('tablist displays class', () => {
    cy.contains('button > span', 'Save').click()

    cy.task('dbQuery', {'query': 'SELECT * FROM auto_db.public.requests'})
      .then(queryResponse => {
        expect(queryResponse[0]).to.deep.contain({
          id: 1,
          author_id: 4,
          type_id: 1,
        })
      })
  })

})

CodePudding user response：

If you look at the implementation for cypress-postgres it's similar but they break up the response/return to fit the call to pgp.end() in between.

Since it sounds like the 1st connection isn't closing, I'd suspect the .finally() call isn't working.

const pgp = require('pg-promise')();
const postgresConfig = require(require('path').resolve('cypress.json'));

function dbConnection(query, userDefineConnection) {
  const db = pgp(userDefineConnection || postgresConfig.db);
  let response = db.any(query)
  pgp.end()
  return response
}

/**@type {Cypress.PluginConfig} */
module.exports = (on, config) => {
  on("task", {
    dbQuery: (query) => dbConnection(query.query, query.connection)
  });
}

You should be able to get rid of the postgresConfig line since (on, config) is the same (in fact it's better because you might want to overwrite some config on the command line).

const pgp = require('pg-promise')();

/**@type {Cypress.PluginConfig} */
module.exports = (on, config) => {

  function dbConnection(query, userDefineConnection) {
    const db = pgp(userDefineConnection || config.db);
    let response = db.any(query)
    pgp.end()
    return response
  }

  on("task", {
    dbQuery: (query) => dbConnection(query.query, query.connection)
  });
}

CodePudding user response：

The problem was that new record in database has been creating not right away and cypress just was looking in db earlier that creating. Adding of waiting before db checking helped.