ERROR: yaml.parser.ParserError: while parsing a block mapping - docker-compose

Question

I'm building Iroha for which i'm running a script for environment setup which is internally calling the docker-compose.yml, where i"m getting the error:
ERROR: yaml.parser.ParserError: while parsing a block mapping
in "/home/cdac/iroha/docker/docker-compose.yml", line 3, column 5
expected <block end>, but found '<scalar>'
in "/home/cdac/iroha/docker/docker-compose.yml", line 13, column 6
docker-compose.yml file is showing below.
services:
node:
image: hyperledger/iroha:develop-build
ports:
- "${IROHA_PORT}:50051"
- "${DEBUGGER_PORT}:20000"
environment:
- IROHA_POSTGRES_HOST=${COMPOSE_PROJECT_NAME}_postgres_1
- IROHA_POSTGRES_PORT=5432
- IROHA_POSTGRES_USER=iroha
- IROHA_POSTGRES_PASSWORD=helloworld
- CCACHE_DIR=/tmp/ccache
export G_ID=$(id -g $(whoami))
export U_ID=$(id -g $(whoami))
user: ${U_ID:-0}:${G_ID:-0}
depends_on:
- postgres
tty: true
volumes:
- ../:/opt/iroha
- ccache-data:/tmp/ccache
working_dir: /opt/iroha
cap_add:
- SYS_PTRACE
security_opt:
- seccomp:unconfined
postgres:
image: postgres:9.5
environment:
- POSTGRES_USER=iroha
- IROHA_POSTGRES_PASSWORD=helloworld
command: -c 'max_prepared_transactions=100'
volumes:
ccache-data:
any help will be appreciate, thanks in advance.

Answer 1

These lines are not belongs to the docker-compose syntax
export G_ID=$(id -g $(whoami))
export U_ID=$(id -g $(whoami))
Also this line wont be able to work as expected
user: ${U_ID:-0}:${G_ID:-0}
You should write your own shell script and use it as an entry point for the docker container (this should be done in the Dockerfile step) then run a container directly from the image that you have created without the need to assign a user or export anything within the docker-compose as it will be executed once your container is running.
Check the following URL which contains more explanation about the allowed keywords in docker-compose: Compose File: Service Configuration Reference

Answer 2

#MostafaHussein I removed the above 3 lines then executed the run-iroha-dev.sh script, and it started to work. it attached me to /opt/iroha in docker container and downloaded hyperledger/iroha:develop-build and iroha images and launched two containers.
is it same what you are suggesting?