Bash script to fetch public keys of a github user

get-github-keys

#!/bin/bash

# get-github-keys
# pipe the output to an ~/.ssh/authorized_keys file to grant ssh access
# of a system to a github user. Probably has other uses as well!

set +x
set +e
set -u
set -o pipefail

function __usage() {
    echo "Usage: $0 GITHUB_USERNAME" >&2
    exit 1
}

function __get_github_keys() {
  NAME=${@:1}
  case $NAME in
      "--help"|"-h"|"")
        __usage
        ;;
      *)
  esac
  URL="https://github.com/$NAME.keys"
  KEY_DATA=$( curl -sfL "$URL" )
  EXIT_CODE=$?
  if [ 0 -ne "$EXIT_CODE" ]; then
      echo "Failed to get $URL" >&2
      exit "$EXIT_CODE"
  fi

  if [ -z "$KEY_DATA" ] ; then
      echo "No keys found for $NAME" >&2
      exit 0
  fi

  echo
  echo "# $URL"
  echo "$KEY_DATA"
  echo
}

__get_github_keys "$@"