Mongos should be allowed to run initdb.d scripts too

[ravanscafi]

Basically, I'm trying to configure shards when running mongos:

sh.addShard("rs1/db")

But the scripts in docker-entrypoint-initdb.d only run for mongod:

mongo/3.6/docker-entrypoint.sh

Lines 192 to 318 in 59fba66

	if [ "$originalArgOne" = 'mongod' ]; then
	file_env 'MONGO_INITDB_ROOT_USERNAME'
	file_env 'MONGO_INITDB_ROOT_PASSWORD'
	# pre-check a few factors to see if it's even worth bothering with initdb
	shouldPerformInitdb=
	if [ "$MONGO_INITDB_ROOT_USERNAME" ] && [ "$MONGO_INITDB_ROOT_PASSWORD" ]; then
	# if we have a username/password, let's set "--auth"
	_mongod_hack_ensure_arg '--auth' "$@"
	set -- "${mongodHackedArgs[@]}"
	shouldPerformInitdb='true'
	elif [ "$MONGO_INITDB_ROOT_USERNAME" ] || [ "$MONGO_INITDB_ROOT_PASSWORD" ]; then
	cat >&2 <<-'EOF'
	error: missing 'MONGO_INITDB_ROOT_USERNAME' or 'MONGO_INITDB_ROOT_PASSWORD'
	both must be specified for a user to be created
	EOF
	exit 1
	fi
	if [ -z "$shouldPerformInitdb" ]; then
	# if we've got any /docker-entrypoint-initdb.d/* files to parse later, we should initdb
	for f in /docker-entrypoint-initdb.d/*; do
	case "$f" in
	*.sh|*.js) # this should match the set of files we check for below
	shouldPerformInitdb="$f"
	break
	;;
	esac
	done
	fi
	# check for a few known paths (to determine whether we've already initialized and should thus skip our initdb scripts)
	if [ -n "$shouldPerformInitdb" ]; then
	dbPath="$(_dbPath "$@")"
	for path in \
	"$dbPath/WiredTiger" \
	"$dbPath/journal" \
	"$dbPath/local.0" \
	"$dbPath/storage.bson" \
	; do
	if [ -e "$path" ]; then
	shouldPerformInitdb=
	break
	fi
	done
	fi
	if [ -n "$shouldPerformInitdb" ]; then
	mongodHackedArgs=( "$@" )
	if _parse_config "$@"; then
	_mongod_hack_ensure_arg_val --config "$tempConfigFile" "${mongodHackedArgs[@]}"
	fi
	_mongod_hack_ensure_arg_val --bind_ip 127.0.0.1 "${mongodHackedArgs[@]}"
	_mongod_hack_ensure_arg_val --port 27017 "${mongodHackedArgs[@]}"
	_mongod_hack_ensure_no_arg --bind_ip_all "${mongodHackedArgs[@]}"
	# remove "--auth" and "--replSet" for our initial startup (see https://docs.mongodb.com/manual/tutorial/enable-authentication/#start-mongodb-without-access-control)
	# https://github.com/docker-library/mongo/issues/211
	_mongod_hack_ensure_no_arg --auth "${mongodHackedArgs[@]}"
	if [ "$MONGO_INITDB_ROOT_USERNAME" ] && [ "$MONGO_INITDB_ROOT_PASSWORD" ]; then
	_mongod_hack_ensure_no_arg_val --replSet "${mongodHackedArgs[@]}"
	fi
	sslMode="$(_mongod_hack_have_arg '--sslPEMKeyFile' "$@" && echo 'allowSSL' || echo 'disabled')" # "BadValue: need sslPEMKeyFile when SSL is enabled" vs "BadValue: need to enable SSL via the sslMode flag when using SSL configuration parameters"
	_mongod_hack_ensure_arg_val --sslMode "$sslMode" "${mongodHackedArgs[@]}"
	if stat "/proc/$$/fd/1" > /dev/null && [ -w "/proc/$$/fd/1" ]; then
	# https://github.com/mongodb/mongo/blob/38c0eb538d0fd390c6cb9ce9ae9894153f6e8ef5/src/mongo/db/initialize_server_global_state.cpp#L237-L251
	# https://github.com/docker-library/mongo/issues/164#issuecomment-293965668
	_mongod_hack_ensure_arg_val --logpath "/proc/$$/fd/1" "${mongodHackedArgs[@]}"
	else
	initdbLogPath="$(_dbPath "$@")/docker-initdb.log"
	echo >&2 "warning: initdb logs cannot write to '/proc/$$/fd/1', so they are in '$initdbLogPath' instead"
	_mongod_hack_ensure_arg_val --logpath "$initdbLogPath" "${mongodHackedArgs[@]}"
	fi
	_mongod_hack_ensure_arg --logappend "${mongodHackedArgs[@]}"
	pidfile="${TMPDIR:-/tmp}/docker-entrypoint-temp-mongod.pid"
	rm -f "$pidfile"
	_mongod_hack_ensure_arg_val --pidfilepath "$pidfile" "${mongodHackedArgs[@]}"
	"${mongodHackedArgs[@]}" --fork
	mongo=( mongo --host 127.0.0.1 --port 27017 --quiet )
	# check to see that our "mongod" actually did start up (catches "--help", "--version", MongoDB 3.2 being silly, slow prealloc, etc)
	# https://jira.mongodb.org/browse/SERVER-16292
	tries=30
	while true; do
	if ! { [ -s "$pidfile" ] && ps "$(< "$pidfile")" &> /dev/null; }; then
	# bail ASAP if "mongod" isn't even running
	echo >&2
	echo >&2 "error: $originalArgOne does not appear to have stayed running -- perhaps it had an error?"
	echo >&2
	exit 1
	fi
	if "${mongo[@]}" 'admin' --eval 'quit(0)' &> /dev/null; then
	# success!
	break
	fi
	(( tries-- ))
	if [ "$tries" -le 0 ]; then
	echo >&2
	echo >&2 "error: $originalArgOne does not appear to have accepted connections quickly enough -- perhaps it had an error?"
	echo >&2
	exit 1
	fi
	sleep 1
	done
	if [ "$MONGO_INITDB_ROOT_USERNAME" ] && [ "$MONGO_INITDB_ROOT_PASSWORD" ]; then
	rootAuthDatabase='admin'
	"${mongo[@]}" "$rootAuthDatabase" <<-EOJS
	db.createUser({
	user: $(_js_escape "$MONGO_INITDB_ROOT_USERNAME"),
	pwd: $(_js_escape "$MONGO_INITDB_ROOT_PASSWORD"),
	roles: [ { role: 'root', db: $(_js_escape "$rootAuthDatabase") } ]
	})
	EOJS
	fi
	export MONGO_INITDB_DATABASE="${MONGO_INITDB_DATABASE:-test}"
	echo
	for f in /docker-entrypoint-initdb.d/*; do

Does it make sense to run for mongos too?

[wglambert]

Is this a duplicate of #339?

#339 (comment)
The docker-entrypoint-initdb.d scripts run during an initialization period (and only if the database is empty), during which the container is only listening on localhost so trying to initiate a cluster during that period isn't possible as it won't resolve it's own container hostname.

[ravanscafi]

Actually I did a pretty big jerry rig and was able to configure it, but I did from other container running mongod, so it would work with mongos

The hack is nohup the script with an sleep, so the command runs and the servers are started, then the config is applied.

something like this:

nohup bash -c "sleep 10 && echo 'rs.initiate({_id: \"mongors1\", members: [{_id: 0, host: \"db\"}]})' | mongo --host db" &

It's really really ugly, but it works.
So I'm not sure how exactly related it is with the other issue, but having the ability to run scripts with mongos too would simplify my workflow.

[Shogoki]

Not sure, if this is directly related, but i had a similiar issue.
I wanted to initialize a replicaset in my local dev container.
I ended up with the following workaround.

#!/bin/bash


if [ "$1" != "CHILD" ]
    then
    # we are the main process so we need to start our child
    echo "STARTING CHILD"
    /bin/bash $BASH_SOURCE CHILD &
else
    # we are the CHILD so we run the actual init code:
    echo "Starting BG init script. Wating for Mongo to listen on $MONGO_HOST"
    ## waiting for mongo to be available
    until nc -z $MONGO_HOST 27017
    do
        sleep 1
    done
    echo "going on.. Initialize replset"
    # initializing replicaset
    mongo --eval  "rs.initiate({ _id: \"$MONGO_REPLSET\", version: 1,  members: [  { _id: 0, host : \"$MONGO_HOST\" },  ] });"

    mongo --eval 'rs.status()'
fi  

This required me to set MONGO_HOST to the name of the service (in my compose file) and MOGO_REPLSET to the replSet Name.

[alitoufighi]

I actually didn't figure out how the workarounds mentioned here can be used to run a mongos command in initialization step, but I have the same issue. If anybody can explain what I can do to add a shard automatically on startup, I would be so grateful.

I need to setup a sharded cluster that has the config server and shards up and running. The only requirement here is to run a mongos container and perform sh.addShard() on it.