Clean up Dockerfile, add known_hosts file

@appinteractive it's troublesome to add the SSH private key via
environment variable. You have to convert newlines to spaces and convert
them back - which I think is error prone. I hope we can transfer the
private key file on to our deployed container later on.

db-migration-worker/.gitignore

@@ -1 +1 @@
-id_rsa
+.ssh/id_rsa

db-migration-worker/.ssh/.dockerignore

@@ -0,0 +1 @@
+.ssh/id_rsa

db-migration-worker/.ssh/known_hosts

@@ -0,0 +1 @@
+|1|GuOYlVEhTowidPs18zj9p5F2j3o=|sDHJYLz9Ftv11oXeGEjs7SpVyg0= ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBM5N29bI5CeKu1/RBPyM2fwyf7fuajOO+tyhKe1+CC2sZ1XNB5Ff6t6MtCLNRv2mUuvzTbW/HkisDiA5tuXUHOk=

db-migration-worker/Dockerfile

@@ -1,9 +1,7 @@
 FROM mongo:latest
-ARG KNOWN_HOST
 
 RUN apt-get update
 RUN apt-get -y install openssh-client
-COPY id_rsa /root/.ssh/id_rsa
-# RUN ssh-keyscan -H $KNOWN_HOST >> /root/.ssh/known_hosts
+COPY .ssh /root/.ssh/
 COPY import.sh .
 

db-migration-worker/import.sh

@@ -1,6 +1,6 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
-for var in "SSH_USERNAME" "SSH_HOST" "MONGODB_USERNAME" "MONGODB_PASSWORD" "MONGODB_DATABASE" "NEO4J_USERNAME" "NEO4J_PASSWORD" "MONGODB_AUTH_DB"
+for var in "SSH_USERNAME" "SSH_HOST" "MONGODB_USERNAME" "MONGODB_PASSWORD" "MONGODB_DATABASE" "MONGODB_AUTH_DB"
 do
   if [[ -z "${!var}" ]]; then
     echo "${var} is undefined"
@@ -14,10 +14,11 @@ echo "MONGODB_USERNAME         ${MONGODB_USERNAME}"
 echo "MONGODB_PASSWORD         ${MONGODB_PASSWORD}"
 echo "MONGODB_DATABASE         ${MONGODB_DATABASE}"
 echo "MONGODB_AUTH_DB          ${MONGODB_AUTH_DB}"
-echo "NEO4J_USERNAME           ${NEO4J_USERNAME}"
-echo "NEO4J_PASSWORD           ${NEO4J_PASSWORD}"
 echo "-------------------------------------------------"
 
+mongo ${MONGODB_DATABASE} --eval "db.dropDatabase();"
+rm -f /mongo-export/*
+
 ssh -4 -M -S my-ctrl-socket -fnNT -L 27018:localhost:27017 -l ${SSH_USERNAME} ${SSH_HOST}
 mongodump --host localhost -d ${MONGODB_DATABASE} --port 27018 --username ${MONGODB_USERNAME} --password ${MONGODB_PASSWORD} --authenticationDatabase ${MONGODB_AUTH_DB} --gzip --archive | mongorestore --gzip --archive
 ssh -S my-ctrl-socket -O check -l ${SSH_USERNAME} ${SSH_HOST}

docker-compose.override.yml

@@ -18,15 +18,12 @@ services:
       - 7474:7474
     environment:
       - NEO4J_apoc_import_file_enabled=true
-      - "NEO4J_USERNAME=${NEO4J_USERNAME}"
-      - "NEO4J_PASSWORD=${NEO4J_PASSWORD}"
   db-migration-worker:
     build:
       context: db-migration-worker
-      args:
-        - "KNOWN_HOST=${SSH_HOST}"
     volumes:
       - mongo-export:/mongo-export
+      - ./db-migration-worker/.ssh/:/root/.ssh/
     networks:
       - hc-network
     environment: