foam-obsidian-importer.js

// foam-obsidian-importer.js
// Import from obsidian to foam
//
// • Copy all files recursively from SRC_DIR to DST_DIR.
// • For each .md file:
//   - rename to kebab-case.md 
//   - add header "# filename /n/n"
//   - fix internal links and attachments links
// • Copy any other (non .md) file.
//
// Obsidian attachments will be imported from ATTACHMENTS_DIR
//
// Usage: 
// 1. npm install fs-extra slugify prepend-file
// 2. edit SRC_DIR, DST_DIR, ATTACHMENTS_DIR
// 3. node foam-obsidian-importer.js

// SRC_DIR (obsdian); DST_DIR (foam)
const SRC_DIR = "/projects/obsidian";
const DST_DIR = "/projects/foam/imported";
// folder where obsidian attachments are stored, relative to SRC_DIR
const ATTACHMENTS_DIR = "attachments/"

const path = require("path");
const fs = require("fs-extra");
const slugify = require("slugify");
const prependFile = require("prepend-file");

// get files in dir
async function getFiles(dir) {
    const dirents = await fs.promises.readdir(dir, {
        withFileTypes: true,
    });
    const files = await Promise.all(
        dirents.map((dirent) => {
            const res = path.resolve(dir, dirent.name);
            return dirent.isDirectory() ? getFiles(res) : res;
        })
    );
    return Array.prototype.concat(...files);
}

// fix internal links for file and write to dst_path
function fix_internal_links(file, dst_path) {
    // read file
    var data = fs.readFileSync(file, "utf-8");
    // fix internal links
    var re_internal_links = /\[\[(.*)\]\]/gm
    data = data.replace(re_internal_links,
        (match, p1) => {
            return '[[' + slugify(p1.toLowerCase()) + ']]'
        }
    )
    // fix file links
    var re_file_links = /\[\[((.*)\.(png|jpg|gif|svg))\]\]/gm
    data = data.replace(re_file_links,
        (match, p1, p2, p3) => {
            let rlt_path = path.relative(SRC_DIR, path.parse(file).dir);
            let rlt_depth = (rlt_path.match(/\//g) || []).length + 1
            return '[' + p2 + '](' + '../'.repeat(rlt_depth) + ATTACHMENTS_DIR + slugify(p1.toLowerCase()) + ')'
        }
    )
    //  save file
    fs.writeFileSync(dst_path, data, "utf-8");
}

// do the magic
function process(file) {
    let current_file = path.parse(file);
    let file_slug = slugify(current_file.name.toLowerCase());
    let rlt_path = path.relative(SRC_DIR, current_file.dir);
    var dst_path = path.resolve(DST_DIR, rlt_path, file_slug + current_file.ext);
    let dst_file = path.parse(
        path.resolve(DST_DIR, rlt_path, file_slug + current_file.ext)
    );
    // create dst dir if not exists
    fs.ensureDirSync(dst_file.dir);
    // if markdown
    if (current_file.ext == ".md") {
        // prepend header "# <Filename> \n\n"
        prependFile(
            dst_path,
            "# " +
            current_file.name.charAt(0).toUpperCase() +
            current_file.name.slice(1) +
            "\n\n",
            (err) => {
                if (err) {
                    console.log(err);
                }
            }
        );
        // fix relative links
        fix_internal_links(file, dst_path)
    // if any other file extension
    } else {
        // copy file to dst dir
        fs.copySync(file, dst_path);
    }
}

function main() {
    getFiles(SRC_DIR)
        .then((files) =>
            files.forEach((src_file) => {
                process(src_file);
            })
        )
        .catch((e) => console.error(e));
}

main();

Hey thanks for this, super neat! I'm just starting to think to modify this to work with nb style linking, which requires the relative path to the notebook root. This probably requires:

• changing filenames first, building a dir with old and new filenames, and path, in the process
• when replacing the links, cross-referencing the old link with the old file-name and supplementing the known relative path in front of the new slug

Sadly, my JS skills are beyond rusty. Ah well - a holiday project.

Thanks again for the cool work!