WebSocket error: connect ECONNREFUSED on Synology NAS

[otherfutures]

Describe the bug
Can't seem to scrape page while using Playwright, although text/HTML (the default option) works fine. When I try to switch requests to use the Playwright webdriver, I get the above error (consequently, it never manages to grab a screenshot of the page): WebSocket error: connect ECONNREFUSED 172.31.0.3:3000

I've tried looking at the other help posts with the same error, but none were resolved (except one involving Selenium which didn't seem relevant to what's happening here).

I've also tried restarting the containers before posting this (which didn't work, obviously).

To Reproduce

This is the docker compose I used to build the project on the NAS using Container Manager:

services:
 changedetection:
    image: dgtlmoon/changedetection.io
    container_name: changedetection
    hostname: changedetection
    volumes:
      - /volume1/docker/changedetection:/datastore
    environment:
       - PLAYWRIGHT_DRIVER_URL=ws://playwright-chrome:3000/?stealth=1&--disable-web-security=true
    ports:
      - 5054:5000
    restart: always
    networks:
     - changedetection
    depends_on:
      playwright-chrome:
        condition: service_started

 playwright-chrome:
    container_name: playwright-chrome
    hostname: playwright-chrome
    image: browserless/chrome
    restart: unless-stopped
    networks:
      - changedetection
    environment:
      - PREBOOT_CHROME=true
      - DEFAULT_BLOCK_ADS=true
      - DEFAULT_STEALTH=true
    
volumes:
 changedetection:

networks:
   changedetection:
     name: changedetection
     driver: bridge
     ipam: 
       config:
         - subnet: 172.31.0.0/16
           gateway: 172.31.0.1

[Constantin1489]

I tried your setting with podman-compose(you may ignore this) and your setting worked. hmm..
BTW, with your config, you will use an older version(v0.45.2)

Also, I suggest opening the port for the PLAYWRIGHT container and accessing the port with your browser, ensuring the container is running. See also: https://stackoverflow.com/a/67253741/20307768

OR instead, you can open "browser steps" and click play button. When I used your yml, it didn't work at first but after the "browser steps" thing worked.

[Constantin1489]

@otherfutures

ghcr.io/dgtlmoon/changedirection.io

ghcr.io/dgtlmoon/changedirection.io:0.45.8

unable to access the IP:port through my browser

 playwright-chrome:
...
    ports:
      - 5055:3000
...

and access the container with the exposed port(5055) in your browser like you accessed the changedetection container.

mistake here though.

I don't think so. Your yml setting works for me. "Maybe" there will be some docker version error, or your NAS doesn't have enough memory, and so on. The reason may vary. I have their router. When I contact them, they are really helpful. they really accessed my router(of course, I opened it for them) and checked the problem. BTW, If I were you, I would try with the new image above and contact the manufacturer!

See also: https://docs.docker.com/compose/compose-file/05-services/#long-syntax-1

[otherfutures]

So, I tried again with the above edits, but unfortunately got the same result again. Weirdly, I can't access the playwright container (I also tried the subnet IP & port) regardless of it being port 3000 or 5055, although accessing the changedetector container was never a problem.

But! I finally tried just building the image on my computer with the docker compose file & it worked: I was able to access both containers via my web browser & entering localhost:5054 & localhost:5055; changedetection captured a screenshot without touching anything in the playwright container; it sometimes did require first going through Browser Steps, as you mentioned.

I must conclude there's something about my/the Synology NAS &/or its instance of Docker (i.e. Container Manager) that must be causing this issue. I also tried updating docker-compose by SSHing into the NAS but this also ultimately gave me the same error (the same as all the other attempts) despite the docker-compose version matching the one on my computer, as did trying to edit both the IP & port in PLAYWRIGHT_DRIVER_URL= to all possible combinations while restarting the containers with every edit. But, as I said, the local machine instance worked immediately. Strange.

All the same, thank you all for your help!

[Constantin1489]

#627 (comment)

[otherfutures]

I also saw this when I was trying to troubleshoot on my own, but was unable to figure out what to put for BASE_URL=.

I gave it another try just now (changing only the port number for both PORT= & ports: to 5054 as well as trying out a variety of possible URLs/IP/IP:port addresses for BASE_URL=) but kept getting stuck due to an error re the playwright container being 'unhealthy' ('dependency failed to start') & so the build would never finish.

[dgtlmoon]

maybe related to your driver: bridge network setup, this is not in our recommended docker-compose.yml

[otherfutures]

@Constantin1489

Thanks for the response! Re the older version, do you mean I should use image: ghcr.io/dgtlmoon/changedirection.io to get the latest version instead?

I'm unable to access the IP:port through my browser (although when I once had browserless/chrome installed manually [ie not through docker compose], I was able to access it). It's my first time making a custom network/subnet for containers, so I might be making a dumb mistake here though. I did come across that stack overflow page when I was trying to troubleshoot on my own & am afraid it might be related to https as everything's on http LAN at the moment (I don't think it's a firewall problem though, as it's off for testing at the moment), but dunno really.

I'm very surprised to hear you say browser steps solved the problem: I tried that too but kept getting a pop up that says "'Response' object is not subscriptable". The log output of the container only has the following to add to that: "Exception when calling step operation goto_url 'Response' object is not subscriptable". I tried this both on a URL I wanted to track changes as well as the default URL for Hacker News that comes with the container.

@dgtlmoon
That could be the case. I'm going off others' docker compose examples since I don't know what I'm doing, if I'm being honest (though, apocryphally, they seemed to work), e.g. this one. The one in my OP I tried because it seemed to have fewer configs, but neither it nor the one in the reddit/pastebin link worked for me.

[dgtlmoon]

@otherfutures I'm unable to support your custom home NAS setup unfortunately, I can only support the environment for which this application is primarily developed for, sorry.

I hope someone else can help you here!

[otherfutures]

@dgtlmoon
Do you mean you recommend that it should be installed only on local machines then? That's my next step if I can't figure this out, but I was hoping to get it working on a server.

Oh, apologies: I thought I did when I wrote that could be the case (I didn't mean to sound as though I'm brushing it off, I meant I really don't know). As I said, I've never had to make a subnet for containers before (all the other containers I've used relied on bridge without subnetting, since it's just the one container, & worked just fine). I'm going off existing docker compose files since that seemed pretty foolproof (since the whole idea is to recreate the environment using the compose file), that's all.

I guess you could call it 'option bingo': I won't deny I don't know precisely what I'm doing, but on the other hand, I'm unaware of how to solve a problem without trying options, especially when reading/searching for existing answers hasn't solved the issue.

[jonoff]

I had a similar issue but force recreating the container (not a plain restart) worked in my case:

docker compose up -d --force-recreate playwright-chrome

[marph91]

For me, hardcoding the IP address of the host system worked: PLAYWRIGHT_DRIVER_URL=ws://<HOST_SYSTEM_IP>:3000/?stealth=1&--disable-web-security=true.

I guess there is a more elegant way using the described network bridge solution, but this did just work for my simple use case.

[dgtlmoon]

Try this recipe https://github.com/dgtlmoon/changedetection.io/wiki/Synology-NAS-setup