beyond that, I think one of highland’s main claims is that it’s a high-level utility belt, so you have thinks like
consume with which to capture any kind of custom state and/or logic handling on a case-by-case basis, so adding things like this probably won’t be useful to most people
this is probably better fodder for a blog post or something like that
I would also suggest diving a little deeper as this may not be a production-ready solution
Hello, I'm looking for advise on following.
Given I have a finite stream of (accounting) transactions from db1() I would like to split this stream into two (or more), e.g. transactions_out and accounts_out and sink them to db2(). What should I use to filter out accounts and sort/unique them? Thank you.
Given I have a finite stream of (accounting) transactions from db1() I would like to split this stream into two (or more), e.g. transactions_out and accounts_out and sink them to db2(). What should I use to filter out accounts and sort/unique them? Thank you.
The argument to the function you pass is a stream, which you can then fork, filter, operate on, and merge the incoming stream values
h([1, 2, 3, 4])
.through(stream => {
const evens = stream.fork()
.filter(x => x % 2 === 0)
const odds = stream.fork()
.filter(x => x % 2 !== 0)
.flatMap(saveToDb)
.reject(() => true)
return h([evens, odds])
.merge()
})
.each(h.log) // 1 3
interesting article that mentions highland: https://medium.com/@jgilbert001/how-do-you-manage-so-many-serverless-functions-7c015cd3c858
Hey all. I'm new to Highland, and working with streams in general. I use Fluture for most of my work. I've got myself in a situation where I need to run filter on a highland stream. However, my filter function currently returns a Future. :/ I've been trying lots of different things, like using map to coerce every value of the stream into a Future, and then using ap to apply transformations but it just seems a bit messy. Any suggestions? I essentially need to iterate over a the values of a stream, and apply a filter on it, but the filter is asynchronous.
ah wait, that’s the wrong way round for you
can you give a little code snippet?
you’re termination condition is the http code
well you can do it with streams too but your way is probably simpler. in fact, you could just create an async function with a while loop if you are worried about blowing the stack
async function f() {
let res = await fetch(‘https://example.com);
while(res.code !== 404) {
res = await fetch(‘https://example.com);
}
}
obviously you’ll want a sleep in there too
then you’ll use
_(f()) inside flatMap
or whatever it is you want to do
i'll give this a spin
but in general my question was more like "there is no built-in combinator" for "do this every X"
like "repeat this stream every X"
'cause i've browsed the api a bit
but to no avail
thanks again
are you thinking of something like this? https://rxjs-dev.firebaseapp.com/api/operators/repeatWhen
haven't really used rxjs... i mean i know what it is... but yeah, something like that
