Generate Homer services from docker labels. Inspired by https://github.com/pawelmalak/flame

docker-homer-generator.sh

#!/bin/bash

_DOCKER_LABEL_NAME="homer.service.name"
_DOCKER_LABEL_URL="homer.service.url"

_DI_RESULT_JSONKEY_CATEGORY="category"
_DI_RESULT_JSONKEY_CATEGORY_ICON="category_icon"
_DI_RESULT_JSONKEY_CATEGORY_ORDER="category_order_index"
_DI_RESULT_JSONKEY_ICON="icon"
_DI_RESULT_JSONKEY_NAME="name"
_DI_RESULT_JSONKEY_DESCRIPTION="description"
_DI_RESULT_JSONKEY_URL="url"
_DI_RESULT_JSONKEY_URL_TARGET="url_target" # https://www.w3schools.com/tags/att_a_target.asp
_DI_RESULT_JSONKEY_ORDER="order_index"

function findDockerContainers() {
    # get all containers that want to be displayed in Homer
    docker ps --filter "label=$_DOCKER_LABEL_URL" --format "{{.Names}}"
}

function readDockerContainersLables() {
    # get the labels from the passed containers and output them as json
    function _jsonDockerInspectResult() {
        jq '{
            '"$_DI_RESULT_JSONKEY_CATEGORY"'      : (."homer.service.category.name" // "Apps"),
            '"$_DI_RESULT_JSONKEY_CATEGORY_ICON"' : (."homer.service.category.icon" // ""),
            '"$_DI_RESULT_JSONKEY_CATEGORY_ORDER"': (."homer.service.category.order_index" // "999"),
            '"$_DI_RESULT_JSONKEY_ICON"'          : (."homer.service.icon" // ""),
            '"$_DI_RESULT_JSONKEY_NAME"'          : (."'"$_DOCKER_LABEL_NAME"'" // ."com.docker.compose.service"),
            '"$_DI_RESULT_JSONKEY_DESCRIPTION"'   : (."homer.service.description" // ."'"$_DOCKER_LABEL_URL"'"),
            '"$_DI_RESULT_JSONKEY_URL"'           : (."'"$_DOCKER_LABEL_URL"'"),
            '"$_DI_RESULT_JSONKEY_URL_TARGET"'    : (."homer.service.url.target" // "_blank"),
            '"$_DI_RESULT_JSONKEY_ORDER"'         : (."homer.service.order_index" // "999")
        }'
    }
    while read containerName; do 
        docker inspect $containerName --format='{{json .Config.Labels}}' | _jsonDockerInspectResult
    done
}

function groupByCategory() {
    # group all containers by the $_DI_RESULT_JSONKEY_CATEGORY

    function _readAll() {
        local inputs=()
        while read input; do
            inputs+=( $input )
        done
        echo ${inputs[@]}
    }

    _readAll | jq -s '
        group_by(.'"$_DI_RESULT_JSONKEY_CATEGORY"') 
        | map({
            '"$_DI_RESULT_JSONKEY_CATEGORY"'        : (.[0].'"$_DI_RESULT_JSONKEY_CATEGORY"'),
            '"$_DI_RESULT_JSONKEY_CATEGORY_ICON"'   : (.[0].'"$_DI_RESULT_JSONKEY_CATEGORY_ICON"'),
            '"$_DI_RESULT_JSONKEY_CATEGORY_ORDER"'  : (.[0].'"$_DI_RESULT_JSONKEY_CATEGORY_ORDER"'),
            items: del(
                .[].'"$_DI_RESULT_JSONKEY_CATEGORY"', 
                .[].'"$_DI_RESULT_JSONKEY_CATEGORY_ICON"',
                .[].'"$_DI_RESULT_JSONKEY_CATEGORY_ORDER"'
            )  
        })'
}

function mapToHomerConfigYAML() {
    # use jq to generate the structure, in JSON, that homer expects 
    # and converted it to yaml
    jq -r '{
        services: [
            . 
            | sort_by(.'"$_DI_RESULT_JSONKEY_CATEGORY_ORDER"', .'"$_DI_RESULT_JSONKEY_CATEGORY"') 
            | .[]
            | {
                name: (.'"$_DI_RESULT_JSONKEY_CATEGORY"'),
                icon: (.'"$_DI_RESULT_JSONKEY_CATEGORY_ICON"' // "" | if . == "" then "" else "fas \(.)" end),
                items: [
                    .items
                    | sort_by(.'"$_DI_RESULT_JSONKEY_ORDER"', .'"$_DI_RESULT_JSONKEY_NAME"') 
                    | .[]
                    | {
                        name: .'"$_DI_RESULT_JSONKEY_NAME"',
                        icon: (.'"$_DI_RESULT_JSONKEY_ICON"' // "" | if . == "" then "" else "fas \(.)" end),
                        subtitle: .'"$_DI_RESULT_JSONKEY_DESCRIPTION"',
                        url: .'"$_DI_RESULT_JSONKEY_URL"',
                        target: .'"$_DI_RESULT_JSONKEY_URL_TARGET"',
                    }
                ] 
            }
        ] 
    }' \
    | yq --prettyPrint e '.' - # convert to yaml
}

function writeToHomerConfig() {
    local configFile="$1"
    # delete the current services
    yq -i e 'del(.services)' "$configFile"
    # add the new services
    yq e '.' - >> "$configFile"
}

# main

# some input checks
if ! command -v jq &> /dev/null; then
    echo "ERROR:"
    echo "  'jq' could not be found."
    echo "  see https://stedolan.github.io/jq/download/ for how to install it."
    exit 1
fi
if ! command -v yq &> /dev/null; then
    echo "ERROR:"
    echo "  'yq' could not be found."
    echo "  see https://mikefarah.gitbook.io/yq/#install for how to install it."
    exit 1
fi

HOMER_CONFIG_FILE="$1"
if [[ -z "$HOMER_CONFIG_FILE" ]]; then
    echo "ERROR:"
    echo "  Pass the path to the homer config file"
    echo ""
    echo "  Usage:"
    echo "      $0 path/to/homer/config.yml"
    exit 1
fi
if [[ ! -f "$HOMER_CONFIG_FILE" ]]; then
    echo "ERROR:"
    echo "  File not found at '$HOMER_CONFIG_FILE'"
    exit 1
fi

# do the job
findDockerContainers \
| readDockerContainersLables \
| groupByCategory \
| mapToHomerConfigYAML \
| writeToHomerConfig $HOMER_CONFIG_FILE

echo "Done"
echo "Check $HOMER_CONFIG_FILE"

Still learning Bash, so for sure things can be improved.
Tested on Raspbian 10 (buster)

With that in mind, this is how I'm using it:

1. add the following labels to your container:
   (i'm adding them via docker compose)

portainer:
    image: portainer/portainer-ce
    ...
    labels:
      "homer.service.category.name": "Applications" // optional, default to: "Apps"
      "homer.service.category.icon": "fa-cloud"  // optional, default to: ""
      "homer.service.category.order_index": 0 // optional, default to: 999 - used to order the category
      "homer.service.icon": "fa-docker" // optional, default to: ""
      "homer.service.name": "Portainer" // optional-ish, default to: "com.docker.compose.service" if docker compose was used
      "homer.service.description": "" // optional, default to : "homer.service.url",
      "homer.service.url": "http://mypi.local:9000" // required
      "homer.service.url.target": "" // optional, default to "_blank"
      "homer.service.order_index": 999 // optional, default to: 999 - used to order service in a category

2. run

docker-homer-generator.sh .config/appdata/homer/config.yml

and .config/appdata/homer/config.yml should now contain

services:
  - name: Applications # from `homer.service.category.name` docker container label
    icon: 'fas fa-cloud' # from `homer.service.category.icon` docker container label
    items:
      - name: Portainer # from `homer.service.name` docker container label
        icon: fas fa-docker # from `homer.service.icon` docker container label
        subtitle: http://mypi.local:9000 # from `homer.service.description` docker container label
        url: http://mypi.local:9000 # from `homer.service.url` docker container label
        target: _blank # from `homer.service.url.target` docker container label