Fetch/Download specific artifact from CircleCI build

circleci_fetch_artifact

#!/usr/bin/env bash

set -euo pipefail

log_debug() {
  local blue="\e[34m"
  local default="\e[39m"
  # ISO8601 timestamp + ms
  local timestamp=$(date +%FT%T.%3NZ)
  echo -e "${blue}${timestamp} [debug] $1${default}" 1>&2
}

circleci() {
  curl -s -H "Circle-Token: $CIRCLE_TOKEN" \
    "https://circleci.com/api/v1.1/project/github/$CIRCLE_PROJECT$1" | jq .
}

fetch_build_artifacts() {
  BUILD_NUM="$1"
  log_debug "Fetching build: $BUILD_NUM"

  artifacts=$(circleci "/$BUILD_NUM/artifacts")

  OUTPUT_DIR="factory_bot_debugger/$BUILD_NUM"

  if [ -d "$OUTPUT_DIR" ]; then
    echo "Artifacts already saved!"
    exit 0
  fi

  mkdir -p "$OUTPUT_DIR"
  files=$(
    echo "$artifacts" \
      | jq '[ .[] | select( .path == "factory_bot_debugger.json" ) ]'
  )

  files_count=$(echo "$files" | jq -r '. | length')
  log_debug "Artifacts count: $files_count"

  ((files_count-=1))
  for index in $(seq 0 $files_count); do
    node_index="$(echo "$files" | jq -r ".[$index].node_index")"
    url="$(echo "$files" | jq -r ".[$index].url")"

    log_debug "Fetching: $url"
    curl -s -L -H "Circle-Token: $CIRCLE_TOKEN" "$url" > "$OUTPUT_DIR/${node_index}.json"
  done
}
export -f fetch_build_artifacts log_debug circleci

build() {
  fetch_build_artifacts "$1"
}

recent() {
  circleci '?limit=10&filter=successful' | jq '.[] | .build_num' \
    | xargs -d '\n' -I {} bash -c 'fetch_build_artifacts "$@"' _ {}
}

command="$1"
shift

usage=$(cat <<-EOF
Usage: $0 build <number>|recent

build <number>
  Fetch artifacts for the specifiec build number

recent
  Fetch artifacts for the most recent successful builds

environment variables
- CIRCLE_TOKEN
  Your CircleCI access token
  Can be created at https://app.circleci.com/settings/user/tokens

- CIRCLE_PROJECT
  The '<owner>/<repo>'. Example with the project
  https://github.com/NixOS/nixpkgs it would be
  CIRCLECI_PROJECT='NixOS/nixpkgs'
EOF
)

case "$command" in
  build) build "$@" ;;
  recent) recent "$@" ;;
  *) echo "$usage" >&2; exit 1 ;;
esac