Angular 2 beta.17: Property 'map' does not exist on type 'Observable'

Question

I just upgraded from Angular 2 beta16 to beta17, which in turn requires rxjs 5.0.0-beta.6. (Changelog here: https://github.com/angular/angular/blob/master/CHANGELOG.md#200-beta17-2016-04-28) In beta16 all was working well regarding Observable/map functionality. The following errors appeared after I upgraded and occur when typescript attempts to transpile:

1. Property 'map' does not exist on type 'Observable' (anywhere where I've used map with an observable)
2. c:/path/node_modules/rxjs/add/operator/map.d.ts(2,16): error TS2435: Ambient modules cannot be nested in other modules or namespaces.
3. c:/path/node_modules/rxjs/add/operator/map.d.ts(2,16): error TS2436: Ambient module declaration cannot specify a relative module name.

I have seen this question/answer but it does not solve the problem: Observable errors with Angular2 beta.12 and RxJs 5 beta.3

My appBoot.ts looks like this (am already referencing rxjs/map):

///<reference path="./../node_modules/angular2/typings/browser.d.ts"/>
import {bootstrap} from "angular2/platform/browser";
import {ROUTER_PROVIDERS} from 'angular2/router';
import {HTTP_PROVIDERS} from 'angular2/http';
[stuff]
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/toPromise';
import {enableProdMode} from 'angular2/core';
import { Title } from 'angular2/platform/browser';


//enableProdMode();
bootstrap(AppDesktopComponent, [
    ROUTER_PROVIDERS,
    HTTP_PROVIDERS,
    Title
]);

Does anybody have any idea what is going haywire?

Answer 1

You need to import the map operator:

import 'rxjs/add/operator/map'

Answer 2

I upgraded my gulp-typescript plugin to the latest version (2.13.0) and now it compiles without hitch.

UPDATE 1: I was previously using gulp-typescript version 2.12.0

UPDATE 2: If you are upgrading to the Angular 2.0.0-rc.1, you need to do the following in your appBoot.ts file:

///<reference path="./../typings/browser/ambient/es6-shim/index.d.ts"/>
import { bootstrap } from "@angular/platform-browser-dynamic";
import { ROUTER_PROVIDERS } from '@angular/router-deprecated';
import { HTTP_PROVIDERS } from '@angular/http';
import { AppComponent } from "./path/AppComponent";
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/toPromise';
// import 'rxjs/Rx'; this will load all features
import { enableProdMode } from '@angular/core';
import { Title } from '@angular/platform-browser';



//enableProdMode();
bootstrap(AppComponent, [
    ROUTER_PROVIDERS,
    HTTP_PROVIDERS,
    Title
]);

The important thing being the reference to es6-shim/index.d.ts

This assumes you have installed the es6-shim typings as shown here:

More on the typings install from Angular here: https://angular.io/docs/ts/latest/guide/typescript-configuration.html#!#typings

Answer 3

Rxjs 5.5 “ Property ‘map’ does not exist on type Observable.

The problem was related to the fact that you need to add pipe around all operators.

Change this,

this.myObservable().map(data => {})

to this

this.myObservable().pipe(map(data => {}))

And

Import map like this,

import { map } from 'rxjs/operators';

It will solve your issues.

Answer 4

In my case it wouldn't enough to include only map and promise:

import 'rxjs/add/operator/map';
import 'rxjs/add/operator/toPromise';

I solved this problem by importing several rxjs components as official documentation recommends:

1) Import statements in one app/rxjs-operators.ts file:

// import 'rxjs/Rx'; // adds ALL RxJS statics & operators to Observable

// See node_module/rxjs/Rxjs.js
// Import just the rxjs statics and operators we need for THIS app.

// Statics
import 'rxjs/add/observable/throw';

// Operators
import 'rxjs/add/operator/catch';
import 'rxjs/add/operator/debounceTime';
import 'rxjs/add/operator/distinctUntilChanged';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/switchMap';
import 'rxjs/add/operator/toPromise';

2) Import rxjs-operator itself in your service:

// Add the RxJS Observable operators we need in this app.
import './rxjs-operators';

Answer 5

If you happen to see this error in VS2015, there's a github issue & workaround mentioned here:

https://github.com/Microsoft/TypeScript/issues/8518#issuecomment-229506507

This did help me resolve the property map does not exist on observable issue. Besides, make sure you have typescript version above 1.8.2

Answer 6

THE FINAL ANSWER FOR THOSE WHO USES ANGULAR 6:

Add the below command in your *.service.ts file"

import { map } from "rxjs/operators";

**********************************************Example**Below**************************************
getPosts(){
this.http.get('http://jsonplaceholder.typicode.com/posts')
.pipe(map(res => res.json()));
}
}

I am using windows 10;

angular6 with typescript V 2.3.4.0

Answer 7

import 'rxjs/add/operator/map';

&

npm install rxjs@6 rxjs-compat@6 --save

worked for me

Answer 8

In Angular 2x

In example.component.ts

import { Observable } from 'rxjs';

In example.component.html

  Observable.interval(2000).map(valor => 'Async value');

In Angular 5x or Angular 6x:

In example.component.ts

import { Observable, interval, pipe } from 'rxjs';
import {switchMap, map} from 'rxjs/operators';

In example.component.html

valorAsync = interval(2500).pipe(map(valor => 'Async value'));

Answer 9

UPDATE Sep 29 2016 for Angular 2.0 Final & VS 2015

The workaround is no longer needed, to fix you just need to install TypeScript version 2.0.3.

Fix taken from the edit on this github issue comment.

Answer 10

As I understand it is because of rxjs last update. They have changed some operators and syntax. Thereafter we should import rx operators like this

import { map } from "rxjs/operators";

instead of this

import 'rxjs/add/operator/map';

And we need to add pipe around all operators like this

this.myObservable().pipe(map(data => {}))

Source is here

Answer 11

As Justin Scofield has suggested in his answer, for Angular 5's latest release and for Angular 6, as on 1st June, 2018, a mere import 'rxjs/add/operator/map'; isn't sufficient to remove the TS error: [ts] Property 'map' does not exist on type 'Observable<Object>'.

It's necessary to run the below command to install the required dependencies: npm install rxjs@6 rxjs-compat@6 --save after which the map import dependency error gets resolved!

Answer 12

I was facing the similar error. It was solved when I did these three things:

1. Update to the latest rxjs:

   npm install rxjs@6 rxjs-compat@6 --save
   

2. Import map and promise:

   import 'rxjs/add/operator/map';
   import 'rxjs/add/operator/toPromise';
   

3. Added a new import statement:

   import { Observable, Subject, asapScheduler, pipe, of, from, interval, merge, fromEvent } from 'rxjs';
   

Answer 13

It looks like latest RxJS requires typescript 1.8 so typescript 1.7 reports the above error.

I solved this issue by upgrading to the latest typescript version.

Answer 14

Similar error messages will pop up when transitioning from version 5 to 6. Here is an answer for the change to rxjs-6.

Import the individual operators, then use pipe instead of chaining.

import { map, delay, catchError } from 'rxjs/operators'; 

source.pipe(
  map(x => x + x),
  delay(4000),
  catchError(err => of('error found')),
).subscribe(printResult);

Answer 15

If you are using angular4 the use below import. it should work .

import 'rxjs/add/operator/map';

If you are using angular5/6 then use map with pipe and import below one

import { map } from "rxjs/operators";

Answer 16

property 'map' does not exist on type 'observable response ' angular 6

Solution: Update Angular CLI And Core Version

ng update @angular/cli           //Update Angular CLi 
ng update @angular/core          //Update Angular Core 
npm install --save rxjs-compat   //For Map Call For Post Method