HA fails to communicate with external API

Development
1

I have HA and an express API running on different images under one Docker container on my ubuntu server. I attempted to configure a switch using the rest platform, but it failed to show up as a switch on my HA dashboard. So, I changes the platform to command_line, using curl to make the requests- this made the switch show up on my dashboard.

I’ve confirmed that the curl commands work when I ssh into the server, and the endpoints on my API are all working as expected. The switch, however, does nothing, fails to log to the Logbook, and the home-assistant.log file is filled with errors and warnings about timeouts.
home-assistant.log:

"home-assistant.log" [readonly] 3L, 617B                                                                                                    1,1           All
2023-06-21 21:44:37.320 ERROR (SyncWorker_0) [homeassistant.components.command_line.utils] Timeout for command: curl -X POST -H "Content-Type: application/json" -d "{\"state\":\"dark\"}" http://192.168.0.41:8081/roku/state
2023-06-21 21:44:37.324 ERROR (MainThread) [homeassistant.components.command_line] Command failed: curl -X POST -H "Content-Type: application/json" -d "{\"state\":\"dark\"}" http://192.168.0.41:8081/roku/state
2023-06-21 21:44:37.326 WARNING (MainThread) [homeassistant.components.command_line] Updating Command Line Switch roku_dark_mode took longer than the scheduled update interval 0:00:30

configuration.yaml:

switch:
  - platform: command_line
    switches:
      roku_dark_mode:
        command_on: 'curl -X POST -H "Content-Type: application/json" -d "{\"state\":\"dark\"}" http://192.168.0.41:8081/roku/state'
        command_off: 'curl -X POST -H "Content-Type: application/json" -d "{\"state\":\"light\"}" http://192.168.0.41:8081/roku/state'
        command_state: 'curl http://192.168.0.41:8081/roku/state | jq -r ".state"'
        value_template: '{{ value == "dark" }}'
# Below is a test switch to confirm that switches were bring picked up.
  - platform: rest
    name: "jsonplaceholder_test"
    resource: https://jsonplaceholder.typicode.com/posts
    body_on: '{"title":"foo","body":"bar","userId":1}'
    body_off: '{"title":"baz","body":"qux","userId":1}'
    headers:
      Content-Type: "application/json; charset=utf-8"

Previous attempt at a rest platform:

- platform: rest
  name: "roku_dark_mode"
  resource: http://192.168.0.41:8081/roku/state
  body_on: '{"state":"dark"}'
  body_off: '{"state":"light"}'
  is_on_template: "{{value_json.state == 'dark'}}"
  headers:
    Content-Type: application/json
2

Heh? I don’t understand that sentence and what it has to do with the rest of your explanations…

What server?

What is 192.168.0.41?

3

Have you exposed port 8081 outside your container? Ie

docker container run -d -p 8081:8081/tcp
4

I found the issue when I switched back the the rest platform for the switch. While the switch still failed to show up on my HA dashboard, an error message in my home-assistant.log explained that the switch was ‘not ready’ and no API endpoint was available.
I realized that there was an issue in communication between the docker images. Homeassistant couldn’t reach 192.168.0.41:8081 (my api).
I initiated an internal network in my docker-compose file and updated the api endpoints to homeserver:8081 which enabled communication between the docker images.
initialize the internal network:

$ docker network create mynetwork

update docker-compose.yaml

"docker-compose.yaml" 68L, 1519B                                                                                                            58,7          All
version: "3.0"
services:

  portainer:
    container_name: portainer
    image: portainer/portainer
    restart: always
    stdin_open: true
    tty: true
    ports:
      - "9000:9000/tcp"
    environment:
      - TZ=America/Denver
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - /opt/portainer:/data
    networks:
      - mynetwork

  homeassistant:
    container_name: homeassistant
    image: "ghcr.io/home-assistant/home-assistant:stable"
    ports:
      - "8123:8123"
    volumes:
      - /opt/homeassistant/config:/config
      - /etc/localtime:/etc/localtime:ro
    restart: unless-stopped
    privileged: true
    #network_mode: host
    networks:
      - mynetwork

  plex:
    image: lscr.io/linuxserver/plex:latest
    container_name: plex
      #network_mode: host
    ports:
      - "32400:32400"
    volumes:
      - /opt/plex/config:/config
      - /opt/plex/tv:/tv
      - /opt/plex/movies:/movies
    restart: unless-stopped
    networks:
      - mynetwork

  homeserver:
    container_name: homeserver
    image: ctheil/homeserver:latest
    ports:
      - "8081:8081"
    volumes:
      - ./data:/app/data # map local data directory to /app/data in container
    restart: unless-stopped
    networks:
      - mynetwork

networks:
  mynetwork:

Adding networks: -mynetwork to each server, and initializing the mynetwork at the bottom enables each server to be reachable via the name, so I can now reach homeserver via homeassistant via the address and port: http://homeserver:8081/api-endpoint

(homeassistant) configuration.yaml

switch:
  - platform: rest
    name: "roku_dark_mode"
    resource: http://homeserver:8081/roku/state
    body_on: '{"state":"dark"}'
    body_off: '{"state":"light"}'
    is_on_template: "{{value_json.state == 'dark'}}"
    headers:
      Content-Type: application/json