make fields startDate, endDate, memberRate and customerRate optional

[imcaizheng]

Notes

• The weekly cost logic is slightly updated so that any resource booking without memberRate are simply ignore when calcuating the weekly cost.
• Also see make fields startDate, endDate, memberRate and customerRate optional taas-es-processor#6

[maxceem]

@imcaizheng the changes look good and I've already merged ES processor changes.

Though for this change we would also need a DB migration script, otherwise we are getting error like:

ERROR : null value in column "start_date" violates not-null constraint

Let's use Sequalize migrations for this:

• https://sequelize.org/master/manual/migrations.html
• create folder migrations where we would put all migrations scripts
• create a migration script to make these fields optional
• create npm commands like:

  "migrate": "./node_modules/.bin/sequelize db:migrate",
  "migrate:undo": "./node_modules/.bin/sequelize db:migrate:undo",
  

I would update the budget for this issue to cover this.

[maxceem]

@imcaizheng all works good.

The only one thing we can improve is to use ENV variable for DB configuration instead of hardcoded values, because we cannot add to config real DB passwords.

Let's use process.env.NEV_VARIABLE_NAME in config, as suggested in docs https://monosnap.com/file/CsG9bjBfpDKUn6Bfz3Cwskee6e3IQk:

• DB_USERNAME
• DB_PASSWORD
• DB_NAME
• DB_HOST

We can use the same variable names for all environments.

[imcaizheng]

@maxceem Fixed.

[maxceem]

Thanks, @imcaizheng. All good.

I would wait for Nkumar to come back on Wednesday before merging this PR as I would need his help to run the migration.