wf_utils

#!/bin/bash
#
# This file contains functions that aid with the scripts located in this
# repo. It should be "sourced" into the script in order to use the functions
# defined.
#
################################################################################


################################################################################
# This function is used to obtain a bearer token (a.k.a. "access token") for the
# BlueXP API and, by extension, Workload Factory API. It requires a
# refresh token that can be obtained from this webpage:
#
#    https://services.cloud.netapp.com/refresh-token
#
# It will store the bearer token in a file named ".blueXP_token" in the
# account's home directory. If the script is called again, it will check to
# see if the modification time of the file is less than 24 hours old and
# if it is, it will just return the contents of the file. If it is older than
# 24 hours, it will create a new token, output it to standard out and
# store it in the file.
################################################################################
get_token() {

  tokenFile="$HOME/.blueXP_token"
  
  if [ -z "$REFRESH_TOKEN" ]; then
    echo "Error: The REFRESH_TOKEN environment variable has not been set." >&2
    exit 1
  fi
  #
  # Ensure all the required commands are available.
  for cmd in curl; do
    if ! command -v $cmd &> /dev/null; then
      echo "Error: $cmd is required but not installed." >&2
      exit 1
    fi
  done
  #
  # According to the documentation tokens are only good for 24 hours.
  # Subtract 5 minutes to be safe.
  let token_valid=60*60*24-60*5
  
  createToken=false
  if [ -r $tokenFile ]; then
    let diff="$(date +%s) - $(date -r $tokenFile +%s)"
    if [ $diff -gt $token_valid ]; then
      createToken=true
    fi
  else
      createToken=true
  fi
  
  if [ $createToken == "true" ]; then
    token=$(curl -s -X POST 'https://netapp-cloud-account.auth0.com/oauth/token' \
    -H 'Content-Type: application/json' \
    --data-raw '{
      "grant_type": "refresh_token",
      "refresh_token": "'$REFRESH_TOKEN'",
      "client_id": "Mu0V1ywgYteI6w1MbD15fKfVIUrNXGWC"
    }' | sed -ne 's/."access_token":"\([^"]*\).*/\1/p')
  
    if [ -z "$token" ]; then
      echo "Error: Unable to obtain a bearer token. Error message:" >&2
      cat $tmpfile >&2
      echo "" >&2
      exit 1
    fi
    echo "$token" > $tokenFile
  fi 
  
  cat $tokenFile
}

################################################################################
# This function runs 'curl' checking for the status code and handling errors.
# It takes the following positional parameters:
#  1. HTTP method (GET, POST, PUT or DELETE)
#  2. Bearer token
#  3. URL to call
#  4. Output file to write the response to
#  5. Error output file to write errors to
#  6. Data to send (for POST or PUT requests)
#  7. Accept header (optional, defaults to "application/json, text/plain, */*")
#  8 -> ??? optional headers to add.
################################################################################
run_curl () {

  method="$(echo $1 | tr 'a-z' 'A-Z')"
  token="$2"
  url="$3"
  output="$4"
  errorOutput="$5"
  data="$6"
  accept="$7"

  if [ -z "$accept" ]; then
    accept="application/json, text/plain, */*"
    if [ $# -lt 6 ]; then
      shift $#
    else
      shift 6
    fi
  else
    shift 7
  fi

  declare -a extraHeaders
  while [ $# -gt 0 ]; do
    extraHeader="$1"
    if [ -n "$extraHeader" ]; then
      extraHeaders+=(-H "$extraHeader")
    fi
    shift
  done

  if [[ -z "$method" || -z "$token" || -z "$url" || -z "$output" || -z "$errorOutput" ]]; then
    echo "Error: Missing required parameters for run_curl function." >&2
    exit 1
  fi
  #
  # Since older versions of curl don't support the %{stderr} variable, using the -o option
  # to redirect output to the $output file and getting the http_code from standard out.
  case "$method" in
    GET)
      curl -sw "%{http_code},%{errormsg}" "$url" \
         -H "Accept: $accept" "${extraHeaders[@]}" \
         -H "Authorization: Bearer $token" -o $output > $errorOutput
      exitCode=$?
      ;;
    POST|PUT)
      curl -X "$method" -sw "%{http_code},%{errormsg}" "$url" \
         -H "Accept: $accept" "${extraHeaders[@]}" \
         -H "Content-Type:application/json" \
         -H "Authorization: Bearer $token" --data "$data" -o $output > $errorOutput
      exitCode=$?
      ;;
    DELETE)
      curl -X DELETE -sw "%{http_code},%{errormsg}" "$url" \
         -H "Accept: $accept" "${extraHeaders[@]}" \
         -H "Authorization: Bearer $token" -o $output > $errorOutput
      exitCode=$?
      ;;
    *)
      echo "Error: Unsupported method '$method'." >&2
      exit 1
      ;;
  esac

  httpCode=$(awk -F, '{print $1}' $errorOutput)
  if [ "$exitCode" != "0" ]; then
    errorMsg=$(awk -F, '{print $2}' $errorOutput)
    echo "Error: curl command failed with exit code $exitCode ($errorMsg)." >&2
    exit 1
  fi 
    
  if [[ -z "$httpCode" || "$httpCode" -gt 299 ]]; then
    echo "Error: HTTP request failed with status code $httpCode." >&2
    #
    # See if there is any useful output in the output file.
    if [ -s "$output" ]; then
      if (jq -r . $output 2> /dev/null) >&2; then
        exit 1
      fi
    fi
    #
    # If not just dump everything to stderr.
    cat $errorOutput $output >&2
    echo 1>&2
    exit 1
  fi
}

################################################################################
# This function URL encodes the input string.
################################################################################
urlencode() {
  echo "$@" | awk -v ORS="" '{ gsub(/./,"&\n") ; print }' | while read l
  do
    c="`echo "$l" | grep '[^-._~0-9a-zA-Z]'`"
    if [ "$l" == "" ]; then
      echo -n "%20"
    else
      if [ -z "$c" ]; then
        echo -n "$l"
      else
        printf %%%02X \'"$c"
      fi
    fi
  done
  echo ""
}

################################################################################
# This function confirms that the user has provided all the required parameters.
# It dependson the "required_options" associative array being defined in the
# script that sources this file. The array should contain key-value pairs
# where the key is the name of the variable to check and the value is the
# error message to display if the variable is not set. The message is displayed
# with printf so it can include formatting characters like \n.
################################################################################
check_required_options () {
  missingParmeter="false"
  for key in "${!required_options[@]}"; do
    if [ -z "${!key}" ]; then
      printf "${required_options[$key]}" >&2
      missingParmeter="true"
    fi
  done
  if [ "$missingParmeter" != "false" ]; then
    usage
  fi
}