dayone2-bear-import.js

var fs = require('fs');
var child_process = require('child_process');

var main = () => {
    var excludedFileNames = /\| Hacker News/;
    var journal = 'worklog';
    fs.readdirSync('.')
        .filter(f => f.match(/\.md$/))
        .map(f => {
            return Object.assign(fs.statSync(f), {
                name: f, photos: [],
            });
        })
        .map(f => {
            return Object.assign(f, {
                body: fs.readFileSync(f.name, 'UTF-8'),
                isoDate: f.birthtime.toISOString().replace(/\.\d*[^Z]/, ''),
            })
        })
        .map(f => {
            (f.body.match(/!\[.*\]\((.*)\)/g) || [])
                .map(img => {
                    if (img.match(/!\[.*\]\((.*)\)/)[1].match(/^http/)) return f;
                    f.body = f.body.replace(img, '[{photo}]');
                    f.photos.push(
                        `'${decodeURIComponent(img.match(/!\[.*\]\((.*)\)/)[1])}'`
                    );
                })
            return f;
        })
        .filter(f => !f.name.match(excludedFileNames))
        .map(test => {
            if (test.photos.length) {
                child_process.execSync(
                    `echo ${escapeShellArg(test.body)} | dayone2 -isoDate=${test.isoDate} -j ${journal} -p ${test.photos.join(' ')} -- new`
                )
            } else {
                child_process.execSync(
                    `echo ${escapeShellArg(test.body)} | dayone2 -isoDate=${test.isoDate} -j ${journal} new`
                )
            }
            fs.unlinkSync(test.name);
        })
};

function escapeShellArg (arg) {
    return `'${arg.replace(/'/g, `'\\''`)}'`;
}

main();

Thanks for sharing! For the other-way round I just created https://github.com/bsingr/dayone2-textbundle