Async Migrations are not run in sequence

[vparpoil]

Let's say you have 2 async migrations that needs to be run.
Migration 2 should wait for Migration 1 to be completed to execute.

Since migrate() function is not async and not awaited, this doesn't work

I will work on a PR for this

[rb365]

In case someone needs quick and dirty way to do this while we wait for the PR to get merged and released

(Adjust sleep time as necessary)

const sleep = (ms: number) => new Promise(resolve => setTimeout(resolve, ms));

const SLEEP_TIME = 2000;

// TODO: remove this hack when they release this PR: https://github.com/percolatestudio/meteor-migrations/pull/90
export const runMigrationSequentially = async (targetVersion: string | number) => {
  if (targetVersion != 'latest' && typeof targetVersion !== 'number') {
    targetVersion = parseInt(targetVersion);
  }
  const currentVersion = await Migrations.getVersion();
  console.log("Current version:", currentVersion, "Target version:", targetVersion)
  const isUp = typeof targetVersion === 'number' 
    ? targetVersion > currentVersion
    : targetVersion === 'latest';
  
  if (isUp) {
    // Get all migration versions between current and target
    const allVersions = Migrations._list.map(m => m.version).sort((a, b) => a - b);
    const versionsToRun = allVersions.filter(v => v > currentVersion);

    console.log("Versions to run:", versionsToRun)
    
    // Run migrations one by one
    for (const version of versionsToRun) {
      console.log(`Running migration ${version}`);
      Migrations.migrateTo(version.toString());
      await sleep(SLEEP_TIME);
    }
  } else {
    // Handle downgrade case
    const targetVersionNum = parseInt(targetVersion as string);
    const versionsToRun = Array.from(
      { length: currentVersion - targetVersionNum },
      (_, i) => currentVersion - i
    );

    console.log("Versions to run:", versionsToRun)
    
    for (const version of versionsToRun) {
      console.log(`Rolling back migration ${version}`);
      Migrations.migrateTo((version - 1).toString());
      await sleep(SLEEP_TIME);
    }
  }
};