Add migration tool for migrating legacy resources

Closes #949

Author: rubensworks

bin/lib/cli.js

@@ -2,6 +2,7 @@ const program = require('commander')
 const loadInit = require('./init')
 const loadStart = require('./start')
 const loadInvalidUsernames = require('./invalidUsernames')
+const loadMigrateLegacyResources = require('./migrateLegacyResources')
 const { spawnSync } = require('child_process')
 const path = require('path')
 
@@ -11,6 +12,7 @@ module.exports = function startCli (server) {
   loadInit(program)
   loadStart(program, server)
   loadInvalidUsernames(program)
+  loadMigrateLegacyResources(program)
 
   program.parse(process.argv)
   if (program.args.length === 0) program.help()

bin/lib/migrateLegacyResources.js

@@ -0,0 +1,64 @@
+const fs = require('fs')
+const Path = require('path')
+const promisify = require('util').promisify
+
+/* Converts the old (pre-5.0.0) extensionless files to $-based files _with_ extensions
+ * to make them work in the new resource mapper (post-5.0.0).
+ * By default, all extensionless files (that used to be interpreted as Turtle) will now receive a '$.ttl' suffix. */
+/* https://www.w3.org/DesignIssues/HTTPFilenameMapping.html */
+
+module.exports = function (program) {
+  program
+    .command('migrate-legacy-resources')
+    .option('-p, --path <path>', 'Path to the data folder, defaults to \'data/\'')
+    .option('-s, --suffix <path>', 'The suffix to add, defaults to \'$.ttl\'')
+    .option('-v, --verbose', 'Path to the data folder')
+    .description('Migrate extensionless data files pre-5.0.0 to turtle-based data files post-5.0.0')
+    .action(async (opts) => {
+      const verbose = opts.verbose
+      const suffix = opts.suffix || '$.ttl'
+      let path = opts.path || 'data'
+      path = path.startsWith(Path.sep) ? path : Path.join(process.cwd(), path)
+      if (verbose) {
+        console.log(`Migrating files in ${path}`)
+      }
+      try {
+        await migrate(path, suffix, verbose)
+      } catch (err) {
+        console.error(err)
+      }
+    })
+}
+
+async function migrate (path, suffix, verbose) {
+  const files = await promisify(fs.readdir)(path)
+  for (const file of files) {
+    const fullFilePath = Path.join(path, file)
+    const stat = await promisify(fs.lstat)(fullFilePath)
+    if (stat.isFile()) {
+      if (shouldMigrateFile(file)) {
+        const newFullFilePath = getNewFileName(fullFilePath, suffix)
+        if (verbose) {
+          console.log(`${fullFilePath}\n  => ${newFullFilePath}`)
+        }
+        await promisify(fs.rename)(fullFilePath, newFullFilePath)
+      }
+    } else {
+      if (shouldMigrateFolder(file)) {
+        await migrate(fullFilePath, suffix, verbose)
+      }
+    }
+  }
+}
+
+function getNewFileName (fullFilePath, suffix) {
+  return fullFilePath + suffix
+}
+
+function shouldMigrateFile (filename) {
+  return filename.indexOf('.') < 0
+}
+
+function shouldMigrateFolder (foldername) {
+  return foldername.indexOf('.') !== 0
+}