Watch not working with docker

[azhar1038]

Bug description

I have created one file named main.ts and am using tsx watch ./main.ts as my start script to watch the file. Locally everything is working fine (Node 20) but when I try to run in a docker container, it does not watch changes in main.ts.
I have mounted my local files to container.

I was expecting it to reload when I make changes in main.ts locally.

Nothing happens. tsx does not reload anything.

I did not get any error

Reproduction

This is my main.ts

console.log('Hello world!');

This is my Dockerfile (I have tried with node:alpine too)

FROM node:18-alpine
WORKDIR /app
COPY package.json .
COPY package-lock.json .
RUN npm install
COPY . .
CMD [ "npm", "run", "start"]

This is the docker-compose.yml

version: '3.8'
services:
  tsx-test:
    build: .
    volumes:
      - .:/app
      - nodeModules:/app/node_modules

volumes:
  nodeModules:

Environment

System:
    OS: Windows 10 10.0.22621
    CPU: (8) x64 Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz
    Memory: 1.23 GB / 7.85 GB
  Binaries:
    Node: 20.1.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 3.5.1 - C:\Program Files\nodejs\yarn.CMD
    npm: 9.6.4 - C:\Program Files\nodejs\npm.CMD
    pnpm: 8.6.7 - C:\Program Files\nodejs\pnpm.CMD
  npmPackages:
    tsx: ^3.12.7 => 3.12.7 

BTW, I am using Windows 11 not 10

Can you work on a fix?

• I’m interested in opening a pull request to address this issue.

[privatenumber]

I don't use Docker but if you want to investigate and open a PR, feel free.

BTW, the watcher used is chokidar, so perhaps it's a bug in that.

[azhar1038]

Okay, I will check and see if I can find the issue.

[azhar1038]

Hi @privatenumber,
I found the problem!

It is mentioned in Chokidar documentation that we need to set usePolling to true to be able to watch files over a network.

I tested locally and it seems to work but the problem is setting it to true can cause performance issue.

Then I checked Nodemon to see how they have handled this and found that they use a flag --legacy-watch or -L to set usePolling to true.

Shall I add a similar flag to set usePolling in tsx?

[privatenumber]

Thanks for the investigation.
For reference, here's the issue in Chokidar: paulmillr/chokidar#1051

Ideally no new flags... Node.js already added watch mode, and I don't want to end up maintaining a watch feature as it's not the main point of this project.

How does Node.js's watch handle this?

[azhar1038]

Thanks for the reply.
I have checked node experimental watch mode already and it does not handle this either.

[privatenumber]

Okay, lets add a --poll flag that accepts a interval value.

[privatenumber]

Actually, it may not be necessary if we change watchers: #246

Is Parcel's watcher compatible with network files?

[azhar1038]

I am not sure. I will check.

[azhar1038]

I checked @parcel/watcher and it also does not work with Docker on windows.

In fact, no watcher can actually handle this. The problem is in Windows, Docker uses WSL2 which uses its own file system (ext4 for Ubuntu) instead of windows NTFS.
So, when I change something locally in windows, change happens in NTFS but container running in ext4 never gets notified of the change because of this bug in WSL: [WSL2] File changes made by Windows apps on Windows filesystem don't trigger notifications for Linux apps.

So, until that issue is fixed (which will definitely take a long time) we have a few options:

• Move the project to linux file system and do everything from there (Get started with Docker remote containers on WSL 2)
• Use polling (parcel does not support this)
• Switch to linux :)

I think switching to @parcel/watcher is actually a better long term option as Chokidar is a bit less active now.

[matt-sanders]

I'm having a similar issue here which is potentially related. If not, let me know and I can open a new issue. But when using this with Docker on an M2 Mac, changes to files are not being picked up. Interestingly if I use nodemon it works as expected. Example repo here.

[azhar1038]

Both tsx and nodemon uses Chokidar to watch file changes. So, I don't think it is same issue.
However, it is possible that nodemon is setting usePolling or useFsEvents for mac somehow.
Unfortunately I don't have access to any mac, can you please try to see if chokidar is directly working in docker or not? If it does then there is some other issue in tsx.

[matt-sanders]

Can confirm that Chokidar works fine without TSX. I've pushed another script to the above repo as an example.

[azhar1038]

Then your issue is probably related to #246

[matt-sanders]

Hmm, we're actually using Node 18. Interestingly it seems to work with colima but not with Docker Desktop. For now I'm just either continuing with colima or if I really need it, I use Chokidar's polling.

[adam-beck]

I have a similar issue but I don't know if it's related. I'm using Compose Watch instead of volumes. For the first few file changes, it works great. But after like 4-5 it just stops. I'm not sure how to debug either.

In the meantime -- and the reason I'm posting this comment -- is that I resolved to using polling with chokidar. I'm still using tsx but I'm also passing in the environment variable CHOKIDAR_USEPOLLING=true to my container that is running tsx. Seems to "fix" the issue. Well, as good as any other alternative at the moment.

My host OS is PopOS and I'm using a version of Alpine Linux in the container. I'm using Docker Engine (not Docker for Linux).

[azhar1038]

@adam-beck Yes, I just tried compose watch and it is behaving weirdly. When I use:

• experimental native --watch: changes are reflected only once
• tsx watch: changes are reflected around 4 times and then stops
• nodemon: works fine even without polling!
• tsx with CHOKIDAR_USEPOLLING=true works fine as expected

Not sure why tsx watch stops working after some time.
Here is my compose.yml in case anyone is interested.

# compose.yml

services:
  server:
    build:
      context: .
    ports:
      - 3000:3000
    environment:
      - CHOKIDAR_USEPOLLING=true
    develop:
      watch:
        - action: sync
          path: ./src
          target: /app/src
        - action: rebuild
          path: package.json
          target: /app

[adam-beck]

I wrote a simple script to determine if chokidar was picking up the changes via compose watch

const chokidar = require('chokidar');

// One-liner for current directory
chokidar.watch('.').on('all', (event, path) => {
  console.log(event, path);
});

Every change seemed to be picked up. So I'm starting to think it's something within tsx itself. Granted, this is a JS script but I don't think that would matter.

[privatenumber]

I'm likely going to migrate to using Parcel watcher in the near future.

Can one of you give me a reproduction in a GitHub Action environment (or something similar) where I can reproduce this bug? This would help me cover this use-case.

[insanity54]

Hi hi, thank you for tsx. I've been using it for a month or two and I really enjoy it.

I've been bit by this issue so I wanted to see if there's anything I can do to help figure it out. I've made a reproduction repo along with a couple Github actions to test the --watch behavior. I'm not sure it's correct but maybe it's a start.

https://github.com/insanity54/tsx-issue-266/blob/master/.github/workflows/tests.yaml