Using async/await inside for loop [duplicate]

Answer 1

It depends on how you want your async code to be executed: sequentially or in parallel. Anyway, you'd need to add async keyword to use await.

// sequential
export default async (req, callback) => {
  // ...
  for(const [rule, index] of compliance.entries()) {
    const response = await waRuleOverview(req, run.id, rule.id)

    // handle the response
  }
}

// parallel
export default async (req, callback) => {
  // ...
  const responses = await Promise.all(compliance
     .map((rule, index) => waRuleOverview(req, run.id, rule.id))
  )

  // handle responses
  responses.forEach(response => {
    // ...
    // handle response here
  })
}

And finally, if you don't really want your handler to return a Promise but just want it to perform some async actions for side effects.

export default (req, callback) => {
  // ...
  compliance.forEach(/* add */ async (rule, index) => {
    // to use await inside
    let response = await waRuleOverview(req, run.id, rule.id);
    // handle the response
  });
}

But this approach is actually an anti-pattern since it breaks promise chains: bad for composability, error handling and such.