Updating Firestore Documents in Parallel Using Promise.all()

This question concerns the Firestore database, but, more generally, it concerns making async requests in parallel. Simply put, I wish to update multiple Firestore documents as quickly and efficiently as possible by mapping over an array of their document IDs. the .set() method is async (returning a promise) and so I understand that I can wrap the multiple requests – i.e. the map() – in a Promise.all() function, which will return a single promise once all of the requests have resolved. However, it is not at all clear to me whether I should await the set() within the map(). Whichever

Google Cloud Function async with multiple fetch requests

I’m new to both GCF and Javascript async and have been struggling with this. I perform a fetch call initially and then pass that response as a parameter to a second function which then also performs a separate fetch call. During the second function, my empty initialized json gets properties added to it, and when that function completes, I want to notify the exports.helloHttp to then do res.end and terminate. I’ve tried chaining an additional empty then() but it doesn’t seem to be working. My code: Answer Here is the code that would do what you want (replace the fetch

How to alter a API response with Javascript

I wrote this little app that takes in a set of starwars characters and returns images in an array. The result of the above code looks like this : But i would like a result where i can know which image belongs to which keyword. Maybe a format like this or something similar : I tried this : Results were close but not good : Answer client.search returns a Promise. It can be awaited inside the mapping function if you make the mapping function async.

TypeError: fs.createReadStream is not a function

I prefer to use promises rather than callbacks so I’ve used util.promisify. I’ve received TypeError: fs.createReadStream is not a function at const attachments = {attachment: fs.createReadStream(‘kitty.png’)}; lane. How can I solve that? Answer fs.promises is not a superset of fs. While it replaces some methods on fs with methods of the same core name that return a promise, it does not have everything on it that the plain fs has. createReadStream() is a method on the regular require(‘fs’) object, not on require(‘fs’).promises. This is why it is not recommended that you do this: Because then it misleads everyone, including yourself

Javascript: Error in Promise implementation

I’m trying to perform async function and then console log the results with the help of Promise. I’m afraid I haven’t quite grasped the concept yet. I wanted to wait till getlinks finished performing tasks and then console log the result. But the it logs the result as empty even before the getlink is finished. Answer The simplest answer is you’re promise is resolving (return resolve(utlUrls)) before your async code (axios.get(…).then(…)) completes. This is a minimal example to reproduce your problem: It doesn’t work because we return ultUrls before we’ve filled it. We don’t wait for the timeouts to complete.

Not sure how to populate an array within a method that has Promises within it

I have a method that performs some basic mathematical calculations in my Ionic app after fetching data from SQLite DB. I want to show these results on a page but the problem is that I am not sure how to put all these calculated values in an object array. I tried following but the editor is complaining about not resolving promises. To me it looks like I already resolved them by extracting a numeric value from each and assigning them to local variables such as grossMarketable, aphMarketable, amountSold and totalContractDollarAmount. home.ts user-crop.ts (code snippet of UserCropProvider) CalcModel.ts Answer Create a

JavaScript Promises – reject vs. throw

I have read several articles on this subject, but it is still not clear to me if there is a difference between Promise.reject vs. throwing an error. For example, Using Promise.reject Using throw My preference is to use throw simply because it is shorter, but was wondering if there is any advantage of one over the other. Answer There is no advantage of using one vs the other, but, there is a specific case where throw won’t work. However, those cases can be fixed. Any time you are inside of a promise callback, you can use throw. However, if you’re