error TS2687: All declarations of 'observable' must have identical modifiers

Question

I have an Angualr 6 project and im trying to run the following command npm run build. How the below error message appears.

ERROR in node_modules/rxjs/internal/symbol/observable.d.ts(4,9): error TS2687: All declarations of 'observable' must have identical modifiers.

node_modules/@types/node/index.d.ts(167,14): error TS2687: All declarations of 'observable' must have identical modifiers.

Angular Version

  Angular CLI: 6.0.0
    Node: 9.8.0
    OS: darwin x64
    Angular: 6.0.0
    ... animations, cdk, cli, common, compiler, compiler-cli, core
    ... forms, http, language-service, material, platform-browser
    ... platform-browser-dynamic, router

    Package                           Version
    -----------------------------------------------------------
    @angular-devkit/architect         0.6.0
    @angular-devkit/build-angular     0.6.0
    @angular-devkit/build-optimizer   0.6.0
    @angular-devkit/core              0.6.0
    @angular-devkit/schematics        0.6.0 (cli-only)
    @angular/flex-layout              6.0.0-beta.15
    @ngtools/webpack                  6.0.0
    @schematics/angular               0.6.0 (cli-only)
    @schematics/update                0.6.0
    rxjs                              6.1.0
    typescript                        2.7.2
    webpack                           4.6.0

Forgot to mention is only happening in my docker image.

docker build -t $IMG --build-arg env=production .

# Stage 0 - Pre-requisite: Based On Node.js to BUILD and compile Demo Angular App.

FROM node:8.11.2 as node

WORKDIR /app

COPY package.json /app/

RUN npm install

COPY ./ /app/

ARG env

RUN npm run build -- --configuration $env

# Stage 1 - Based On Nginx to have ONLY a compiled and PRODUCTION ready build.

FROM nginx:1.14

COPY --from=node /app/dist/ /usr/share/nginx/html

COPY ./nginx-custom.conf /etc/nginx/conf.d/default.conf

Answer 1

Had the same issue after updating @types/node to 10.3.0. After downgrading to version 10.1.4 everything is working again. I think rxjs has to be updated to work with the newest @types/node version. So at the moment, just use the older version:

npm install @types/[email protected]

UPDATE: The fix on RxJS is already done -> https://github.com/ReactiveX/rxjs/pull/3773 . Now they just have to merge the changes and publish the new version.