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md5-json NPM version Build Status Dependency Status

Creates md5.json to cache md5 hashes of all files. Designed for the situation of high concurrency.


$ npm install md5-json --save


var md5json = require('md5-json');, [options]).get(file, callback)

  • dir path absolute path of the root directory from where you want to read the md5sum of files
  • file path absolute path of the file
  • callback function(err, md5sum)
  • err Error
  • md5sum String the md5sum of the file
  • options Object=
    • no_cache Boolean=false Default to false. If true, md5json will never save cache. NEVER use this option for production environment.
    • save_interval Number=500 interval of miniseconds to save caches.
.get('/path/to/the/file', function(err, md5){
  console.log(file, 'md5:', md5);

Reads the md5 hashes of any files based on the cache inside the dir.

If the md5 hash is not in the cache, md5json will try to generate the md5 value from the file. If succeeded, the md5sum will passed to callback and md5json will save the cache silently without your concern.

Global options

Set the constants will change the options of all newly-created instances of;

md5json.SAVE_INTERVAL = 1000;
md5json.NO_CACHE = true;

md5json.write(dir, callback)

  • dir path
  • callback function(err)

Writes the md5 hashes of all files inside the dir to the cache.

Notice that NEVER use this method in the situation of high concurrency, such live servers.