Delay HTTP-Requests with RxJS operators
I have an Observable myObservable which gets some items emitted with different time intervals. For example the time interval between the first and the second item could be 1 second and for the second and third item this could be 3 seconds.
For each item a HTTP request is send with the method this.sendMessage().
The problem is that the time interval between the request should be at least two second. Delay all request for two seconds is not the best solution. For example for the first request I don't want a delay. I don't want a delay too when the time difference between two emitted items is more than two seconds.
This is a working solution which does what I want. But I wonder if there is a more rxjs-like solution? I play with delay() and delayWhen() but I didn't find a way to get this working.
Does anyone has a solution?
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(async body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
// Wait until delay is over
await new Promise(resolve => setTimeout(resolve, delayTime));
lastSendTimestamp = Date.now();
return await this.sendMessage(body);
}),
).subscribe(result => {
});
javascript rxjs delay
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
add a comment |
I have an Observable myObservable which gets some items emitted with different time intervals. For example the time interval between the first and the second item could be 1 second and for the second and third item this could be 3 seconds.
For each item a HTTP request is send with the method this.sendMessage().
The problem is that the time interval between the request should be at least two second. Delay all request for two seconds is not the best solution. For example for the first request I don't want a delay. I don't want a delay too when the time difference between two emitted items is more than two seconds.
This is a working solution which does what I want. But I wonder if there is a more rxjs-like solution? I play with delay() and delayWhen() but I didn't find a way to get this working.
Does anyone has a solution?
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(async body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
// Wait until delay is over
await new Promise(resolve => setTimeout(resolve, delayTime));
lastSendTimestamp = Date.now();
return await this.sendMessage(body);
}),
).subscribe(result => {
});
javascript rxjs delay
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
add a comment |
I have an Observable myObservable which gets some items emitted with different time intervals. For example the time interval between the first and the second item could be 1 second and for the second and third item this could be 3 seconds.
For each item a HTTP request is send with the method this.sendMessage().
The problem is that the time interval between the request should be at least two second. Delay all request for two seconds is not the best solution. For example for the first request I don't want a delay. I don't want a delay too when the time difference between two emitted items is more than two seconds.
This is a working solution which does what I want. But I wonder if there is a more rxjs-like solution? I play with delay() and delayWhen() but I didn't find a way to get this working.
Does anyone has a solution?
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(async body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
// Wait until delay is over
await new Promise(resolve => setTimeout(resolve, delayTime));
lastSendTimestamp = Date.now();
return await this.sendMessage(body);
}),
).subscribe(result => {
});
javascript rxjs delay
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
I have an Observable myObservable which gets some items emitted with different time intervals. For example the time interval between the first and the second item could be 1 second and for the second and third item this could be 3 seconds.
For each item a HTTP request is send with the method this.sendMessage().
The problem is that the time interval between the request should be at least two second. Delay all request for two seconds is not the best solution. For example for the first request I don't want a delay. I don't want a delay too when the time difference between two emitted items is more than two seconds.
This is a working solution which does what I want. But I wonder if there is a more rxjs-like solution? I play with delay() and delayWhen() but I didn't find a way to get this working.
Does anyone has a solution?
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(async body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
// Wait until delay is over
await new Promise(resolve => setTimeout(resolve, delayTime));
lastSendTimestamp = Date.now();
return await this.sendMessage(body);
}),
).subscribe(result => {
});
javascript rxjs delay
javascript rxjs delay
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
asked Nov 26 '18 at 12:07
Rose NettoyeurRose Nettoyeur
406619
406619
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
You can use timer instead and chain with the async request. There's no need for promise
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
lastSendTimestamp = Date.now();
return timer(delayTime).pipe(concatMap(res=>this.sendMessage(body)));
}),
).
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53480789%2fdelay-http-requests-with-rxjs-operators%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You can use timer instead and chain with the async request. There's no need for promise
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
lastSendTimestamp = Date.now();
return timer(delayTime).pipe(concatMap(res=>this.sendMessage(body)));
}),
).
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
add a comment |
You can use timer instead and chain with the async request. There's no need for promise
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
lastSendTimestamp = Date.now();
return timer(delayTime).pipe(concatMap(res=>this.sendMessage(body)));
}),
).
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
add a comment |
You can use timer instead and chain with the async request. There's no need for promise
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
lastSendTimestamp = Date.now();
return timer(delayTime).pipe(concatMap(res=>this.sendMessage(body)));
}),
).
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
You can use timer instead and chain with the async request. There's no need for promise
let lastSendTimestamp = null;
myObservable.pipe(
concatMap(body => {
// Calculate delay time
let delayTime = 0;
if (!lastSendTimestamp) {
delayTime = 0;
} else if (Date.now() - lastSendTimestamp > 2000) {
delayTime = 0;
} else {
delayTime = 2000 - (Date.now() - lastSendTimestamp);
}
lastSendTimestamp = Date.now();
return timer(delayTime).pipe(concatMap(res=>this.sendMessage(body)));
}),
).
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
answered Nov 26 '18 at 16:45
Fan CheungFan Cheung
2,9541420
2,9541420
add a comment |
add a comment |
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53480789%2fdelay-http-requests-with-rxjs-operators%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
