I am trying to display a markdown file from my computer to the browser window with fetch, but the response (text) is undefined, why is this happening? I leave a codepen with my code. https://codepen.io/matiasConchaSoto/pen/popvQgp somebody help me please. Answer The first .then() has a missing return. Try: Ev…
Tag: promise
Return Promise by Aggregating function calls by synchronous, callback driven using setTimeout, promise based
How to pass a callback that waits for the setTimeout to finish and return a promise. Is there any tweak that can be done here to fix this, when a callback is passed from the function which makes the function to resolve after setTimeout Or call getB before promise.all() and keep the result ready etc The expect…
Wait to resolve Nested loops in a Typescript Subscribe
Objective: I want to wait for all the nested loops to process before I can return final value. Issue: Final value is returned before all the loops are processed. In the below code I am sending paramListToComplete to a data service to create a record and get that new record in the same call, so that I can set …
How to get value from one component to another page/component without navigation?
I have a navbar component in which there is an input search bar. Currently I am taking the value of the search bar and navigate to the Results component and access the input value useParams. I have the let [ result, setResult ] = useState([]); in my Results component because the results can change after the s…
promise not work as expected misunderstanding?
why the data is not logged and promise is logged in the first code? Answer This is only to demonstrate how you would get the data out of the promise (don’t do it this way): The second code is actually a shortened version of: This is the correct way of chaining Promises. As you can see, we return the Pro…
If statement considers FALSE promise as TRUE
I’m making authentication in my app. And have such code changedPasswordAfter retuns promise (true or false) So I run request and get this into console. As you see ttt is FALSE but IF statement decided that it is TRUE . How can I fix that ? Answer Because ttt (which is a very bad name for a variable) is …
Uncaught in promise while waiting for json response
I’m implementing Promises for the first time in JS and am getting uncaught in promise exception in console log while running the below code. I am handling the result of the promise return value in the main function as below and am yet getting the uncaught in promise message: The logic behind the data_pr…
How can I wait for a function to be called by an unknown caller?
I have a callback function that gets called by some other object which I can’t control. I need to wait until this callback function is called, I don’t care by who. I found this hacky workaround, but it sucks: Answer Create a promise, pass its resolve function as callback to the unknown caller some…
Global memoizing fetch() to prevent multiple of the same request
I have an SPA and for technical reasons I have different elements potentially firing the same fetch() call pretty much at the same time.[1] Rather than going insane trying to prevent multiple unrelated elements to orchestrate loading of elements, I am thinking about creating a gloabalFetch() call where: the i…
Capture request response code of rejected promises with Promise.allSettled
I’m using Promise.allSettled to call an array of URLs and I need to capture the response code of the request(s) of the rejected promise(s). Using the value of result.reason provided by Promise.allSettled is not accurate enough to assess the reason of rejection of the promise. I need the request response…