bash2asciicast.sh - Convert a bash script into an asciicast recording

bash2asciicast.sh

#!/usr/bin/env bash

# Convert a bash script into an asciicast recording

set -o errexit -o nounset -o pipefail

USER=karl
WORKDIR="~/workspace"
PROMPT="\u001b]0;Cloud Shell\u0007${USER}@cloudshell:\u001b[1;34m${WORKDIR}\u001b[00m$ \u001bkcloudshell\u001b\\\\"

INPUT_FILE=${1:-}
if [[ -z "${INPUT_FILE}" ]]; then
  echo "Syntax: $0 <path/to/bash-scipt.sh>"
  exit 1
fi

echo '{"version": 2, "width": 233, "height": 69, "timestamp": 1612228753, "env": {"SHELL": "/bin/bash", "TERM": "screen"}}'

TS=0.0
CHAR_STEP=0.05
LINE_STEP=0.5

# Increment TS by the value of the first argument
# Could be done by bc more easily, but Cloud Shell doesn't have bc.
# So use awk instead...
function step() {
    TS=$(echo - | awk "{printf \"%1.1f\", ${TS} + ${1}}")
}

while IFS="" read -r line; do
  echo "[${TS}, \"o\", \"\r\n\"]"
  echo "[${TS}, \"o\", \"${PROMPT}\"]"; step ${LINE_STEP}
  while IFS="" read -r char; do
    echo "[${TS}, \"o\", \"${char//\"/\\\"}\"]"; step ${CHAR_STEP}
  done <<< "$(echo "${line}" | sed -e 's/\(.\)/\1\n/g')"
done < "${INPUT_FILE}"

echo "[${TS}, \"o\", \"\r\n\"]"