get-completed-tasks.sh

#!/usr/bin/env bash

usage() {
cat << EOF
Usage: $(basename $0) -t <token> [-b <backup_file> | -v]

Options:
  -t <token>         Your Todoist API token
  -b <backup_file>   Location of a backup file to append deleted tasks to (optional)
  -v                 Show verbose output (optional)
EOF
    exit
}

join_by() {
    local IFS="$1";
    shift;
    echo "$*";
}

TOKEN=
BACKUP_FILE=
VERBOSE=

while [[ "${1}" != "" ]]; do
    case "${1}" in
        -t ) TOKEN="${2}";;
        -b ) BACKUP_FILE="${2}";;
        -v ) VERBOSE=true;;
    esac
    shift
done

if [ -z "${TOKEN}" ]; then
    usage
fi

if ! command -v uuid 2>&1 > /dev/null; then
    echo "Error: uuid command required" 
    exit 1
fi

IDS=X
OFFSET=0
BATCH_SIZE=200

if [ -n "${BACKUP_FILE}" ]; then
        echo '[' > ${BACKUP_FILE}
fi

until [ -z "${IDS}" ]; do
    TASKS=$(curl -s https://api.todoist.com/sync/v9/completed/get_all \
        -H "Authorization: Bearer ${TOKEN}" \
        -d offset=${OFFSET} \
        -d limit=${BATCH_SIZE} | jq -r ".items ")

    if [ "${TASKS}" == "[]" ]; then
        break
    fi

    if [ -n "${BACKUP_FILE}" ]; then
        if [ "${OFFSET}" != "0" ]; then
	          echo "," >> ${BACKUP_FILE}
        fi
	      echo "${TASKS:1:${#TASKS}-2}" >> ${BACKUP_FILE}
    fi

    OFFSET=$((${OFFSET} + ${BATCH_SIZE}))

    sleep 2
done

if [ -n "${BACKUP_FILE}" ]; then
        echo ']' >> ${BACKUP_FILE}
fi