Single container, multiple pollers?

[frankvdbh]

Hi, We are thinking of the possibility to deploy Harvest as a container on an IoT Edge device.
Is it possible to have a single container image taking care of multiple pollers defined in harvest.yml ?
It seems the --poller flag is required right now and it would simplify management if we could limit it to a single container and some config file mappings.
(Note: in this case there is no requirement on Grafana / Prometheus)

[cgrinds]

hi @frankvdbh - originally we ran multiple pollers in a single container, but we eventually moved away from that design because it didn't fit as well with the single-process-per-container model and meant you needed to restart all pollers when there was any kind of config/template, etc. change.

We'll dig up the Dockerfile and share it with you.

[rahulguptajss]

@frankvdbh You can find the Dockerfile here.

I have made some modifications to these files to ensure that they work with the latest code.

Dockerfile

FROM golang:alpine AS builder

RUN apk add --no-cache git curl && \
    apk add --virtual build-dependencies build-base gcc bash

ARG INSTALL_DIR=/opt/harvest
ARG BUILD_DIR=/opt/home
ARG VERSION=2.0
ARG RELEASE=nightly

WORKDIR $BUILD_DIR

RUN mkdir -p $INSTALL_DIR

COPY . .

RUN make build VERSION=$VERSION RELEASE=$RELEASE && \
    cp -a $BUILD_DIR/harvest.yml $INSTALL_DIR/harvest.yml.example && \
    cp -aR bin $BUILD_DIR/conf $BUILD_DIR/grafana $BUILD_DIR/container/multiPoller/docker-entrypoint.sh $INSTALL_DIR && \
    chmod +x $INSTALL_DIR/docker-entrypoint.sh

FROM alpine:latest

ARG INSTALL_DIR=/opt/harvest

RUN apk add --no-cache bash && \
    mkdir -p $INSTALL_DIR

COPY --from=builder $INSTALL_DIR $INSTALL_DIR

WORKDIR $INSTALL_DIR

ENTRYPOINT ["./docker-entrypoint.sh"]

CMD ["start", "--config", "./harvest.yml"]

docker-entrypoint.sh

#!/bin/bash
bin/harvest "$@"
`exec /bin/sleep infinity`

docker-compose.yml

version: "3.9"
services:
  harvest:
    image: harvest:latest
    ports:
     # Specify the port mappings for pollers to be exposed outside of the container.
      - "12990:12990"
    volumes:
      - ${PWD}/harvest.yml:/opt/harvest/harvest.yml:ro
      - harvest-logs:/var/log/harvest
    restart: always

volumes:
  harvest-logs:
    name: harvest_logs

Steps:

Build Docker Image

docker build -f Dockerfile -t harvest:latest  .

Modify docker-compose.yml file for port mappings and start docker containers

docker-compose -f docker-compose.yml up -d

Stop docker containers

docker-compose -f docker-compose.yml down

[frankvdbh]

Many thanks!, we will check it out