build.sh

#!/bin/bash
# Build a specific Linux target using the local source code via a container image
set -euo pipefail

# This does not work with a symlink to this script
# SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
# See https://stackoverflow.com/a/246128/24637657
SOURCE=${BASH_SOURCE[0]}
while [ -L "$SOURCE" ]; do # resolve $SOURCE until the file is no longer a symlink
  SCRIPT_DIR=$( cd -P "$( dirname "$SOURCE" )" >/dev/null 2>&1 && pwd )
  SOURCE=$(readlink "$SOURCE")
  # if $SOURCE was a relative symlink, we need to resolve it relative to the path where the symlink file was located
  [[ $SOURCE != /* ]] && SOURCE=$SCRIPT_DIR/$SOURCE
done
SCRIPT_DIR=$( cd -P "$( dirname "$SOURCE" )" >/dev/null 2>&1 && pwd )

# Allow us to specify in the caller or pass variables
FLB_DISTRO=${FLB_DISTRO:-}
FLB_OUT_DIR=${FLB_OUT_DIR:-agent}
FLB_NIGHTLY_BUILD=${FLB_NIGHTLY_BUILD:-}
DOCKER=${FLB_DOCKER_CLI:-docker}
CACHE_ID=${CACHE_ID:-main}

# Use this to pass special arguments to docker build
FLB_ARG=${FLB_ARG:-}

while getopts "v:d:b:t:o:" option
do
        case "${option}"
        in
            d) FLB_DISTRO=${OPTARG};;
            o) FLB_OUT_DIR=${OPTARG};;
            *) echo "Unknown option";;
        esac
done

if [ -z "$FLB_DISTRO" ]; then
    echo "$@"
    echo "Usage: build.sh -d DISTRO"
    echo "                 ^    "
    echo "                 | ubuntu/20.04"
    exit 1
fi

# Prepare output directory
if [ -n "$FLB_OUT_DIR" ]; then
    out_dir=$FLB_OUT_DIR
else
    out_dir=$(date '+%Y-%m-%d-%H_%M_%S')
fi

volume="$SCRIPT_DIR/packages/$FLB_DISTRO/$out_dir/"
mkdir -p "$volume"

# Info
echo "FLB_DISTRO            => $FLB_DISTRO"
echo "FLB_OUT_DIR           => $FLB_OUT_DIR"
echo "CACHE_ID              => $CACHE_ID"

MAIN_IMAGE="flb-$FLB_DISTRO"

# We either have a specific Dockerfile in the distro directory or we have a generic multi-stage one for all
# of the same OS type:
# - ubuntu/Dockerfile
# - ubuntu/18.04/Dockerfile
# Use the specific one as an override for any special cases but try to keep the general multi-stage one.
# For the multistage ones, we pass in the base image to use.
#
IMAGE_CONTEXT_DIR="$SCRIPT_DIR/distros/$FLB_DISTRO"
if [[ ! -d "$SCRIPT_DIR/distros/$FLB_DISTRO" ]]; then
    IMAGE_CONTEXT_DIR="$SCRIPT_DIR/distros/${FLB_DISTRO%%/*}"
    FLB_ARG="$FLB_ARG --build-arg BASE_BUILDER=${FLB_DISTRO%%/*}-${FLB_DISTRO##*/}-base --target builder"
fi

if [[ ! -f "$IMAGE_CONTEXT_DIR/Dockerfile" ]]; then
    echo "Unable to find $IMAGE_CONTEXT_DIR/Dockerfile"
    exit 1
fi

# Use full distro target (e.g., "amazonlinux/2", "ubuntu/22.04", "debian/bookworm")
# Remove architecture suffix if present (e.g., "ubuntu/20.04.arm64v8" -> "ubuntu/20.04")
TELEMETRY_FORGE_AGENT_DISTRO_TEMP=${FLB_DISTRO%.arm64v8}
TELEMETRY_FORGE_AGENT_DISTRO_TEMP=${TELEMETRY_FORGE_AGENT_DISTRO_TEMP%.arm32v7}
TELEMETRY_FORGE_AGENT_DISTRO=${TELEMETRY_FORGE_AGENT_DISTRO:-${TELEMETRY_FORGE_AGENT_DISTRO_TEMP}}
TELEMETRY_FORGE_AGENT_PACKAGE_TYPE=${TELEMETRY_FORGE_AGENT_PACKAGE_TYPE:-PACKAGE}

echo "IMAGE_CONTEXT_DIR            => $IMAGE_CONTEXT_DIR"
echo "FLB_NIGHTLY_BUILD            => $FLB_NIGHTLY_BUILD"
echo "TELEMETRY_FORGE_AGENT_DISTRO        => $TELEMETRY_FORGE_AGENT_DISTRO"
echo "TELEMETRY_FORGE_AGENT_PACKAGE_TYPE  => $TELEMETRY_FORGE_AGENT_PACKAGE_TYPE"

if [ "${DOCKER}" = "docker" ]; then
    export DOCKER_BUILDKIT=1
else
    export DOCKER_BUILDKIT=0
fi

# Build the main image - we do want word splitting
# shellcheck disable=SC2086
if ! ${DOCKER} build \
    --build-arg FLB_NIGHTLY_BUILD="$FLB_NIGHTLY_BUILD" \
    --build-arg CACHE_ID="$CACHE_ID" \
    --build-arg TELEMETRY_FORGE_AGENT_DISTRO="$TELEMETRY_FORGE_AGENT_DISTRO" \
    --build-arg TELEMETRY_FORGE_AGENT_PACKAGE_TYPE="$TELEMETRY_FORGE_AGENT_PACKAGE_TYPE" \
    $FLB_ARG \
    -t "$MAIN_IMAGE" \
    -f "$IMAGE_CONTEXT_DIR/Dockerfile" \
    "$SCRIPT_DIR/.."
then
    echo "Error building main docker image $MAIN_IMAGE"
    exit 1
fi

# Compile and package
if ! ${DOCKER} run \
    -v "$volume":/output \
    "$MAIN_IMAGE"
then
    echo "Could not compile using image $MAIN_IMAGE"
    exit 1
fi

echo
echo "Package(s) generated at: $volume"
echo