water-plant-uml/src/plantuml-encoder/encoder.js

CLI tool for live-reloading and/or exporting PlantUML diagrams using the default PlantUML server or a local Docker server.

const fs = require('fs');
const path = require('path');
const zlib = require('zlib');
const encode64 = require('./encode64');

let includes = 0;
const includeLimit = 100;

function readFile(filename, currentPath, root) {
  let filePath = filename;
  if (!path.isAbsolute(filename)) {
    // try relative to file
    filePath = path.join(currentPath || process.cwd(), filename);

    if (!fs.existsSync(filePath)) {
      // try relative to root
      filePath = path.join(root, filename);

      if (!fs.existsSync(filePath)) {
        throw Error(
          `File included in .puml, ${filename}, could not be found in ${currentPath} or ${root} does not exist. Variable names in path not supported.`
        );
      }
    }
  }

  // Resolve any nested includes
  const includedPuml = fs.readFileSync(filePath).toString();
  return resolveIncludes(includedPuml, path.dirname(filePath), root);
}

// Import any include statements inline before encoding
function resolveIncludes(puml, currentPath, root) {
  includes++;
  if (includes > includeLimit) {
    console.error(
      'More than ${nestedLimit} includes found in puml. Not supported, though you can navigate to this code and hardcode to increase the limit.'
    );
    process.exit(1);
  }
  const splitLines = puml.split(/\r?\n/);
  for (let i = 0; i < splitLines.length; i++) {
    const line = splitLines[i].replace(/^\s+/g, '');
    if (line.startsWith('!include ')) {
      const filePath = line
        .substring(line.indexOf('!include ') + 9, line.length)
        .trim();
      // If filepath is in shape <foo/bar>, then it is a std library and should not be read from filesystem
      if (filePath.startsWith('<') && filePath.endsWith('>')) {
        continue;
      }
      try {
        const includeString = readFile(filePath, currentPath, root);
        splitLines[i] = includeString;
      } catch (error) {
        console.warn(error.message);
      }
    }
  }
  return splitLines.join('\n');
}

function deflate(data) {
  return zlib.deflateRawSync(data, { level: 9 }).toString('binary');
}

module.exports = (puml, basepath, root) => {
  includes = 0;
  const includeInlined = resolveIncludes(puml, basepath, root);
  const deflated = deflate(includeInlined);
  return encode64(deflated);
};