fs-crawl

File system operations utilities for node.js that calls your functions on different events for more versatility.

API

The motivation for fs-crawl's API is to be able to run callback functions when crawling a directory in an asynchronous and promised fashion.

fs-crawl uses this model to, for example, create an entire directory structure from an object:

const myDirectoryObj = {
  'daddyFolder': {
    'child.txt': null,  
    'child2.txt': null,
    'childDir1': {
      'grandChild.txt': null
    },
    'childDir2': {}
  },
  'uncleFolder': {},
}
 

Notice fs-crawl expects the following:

• file names must point to null
• a key pointing to an empty object means that key specifies an empty directory

Storing the fs-crawl export in a variable called crawl, and specifying a destination called intoDirPath, we turn our object into a directory using crawl.objToDir:

crawl.objToDir(myDirectoryObj, intoDirPath);

In this case crawl.objToDir passes two callback functions to another fs-crawl utility crawl.crawlDirObj that visits our entire myDirectoryObj running a callback function that creates a file when crawl.crawlDirObj encounters a key that points to null, and running another callback function that creates a directory when crawl.crawlDirObj encounters a key that points to another object.

All files at a given depth are handled first, then all subdirectories.

Similarly, fs-crawl has the remove() utility that visits a specified absolute path, runs crawl.crawlDir() in this case to visit the contents of that directory rather than the contents of an object, and runs two internal callback functions: one that removes a file when one has been found, and another that removes the directory once its depths have been cleared. Basically, fs-crawl gets to all the files at a certain point in the call stack fist, and into the directories depth-first.

crawl.copyOneToMany(fromPath, destinationsArray) copies the contents inside fromPath into an arbitrary number of destinations listed in destinationsArray. It first runs crawl.dirToObj to obtain a copy of the directory structure as an object (i.e. the opposite of crawl.objToDir), then runs callbacks that copy each directory and file it encounters into each of the destinations.

The pattern of running callback functions when a directory or a file is found allows for easily building composable and ever more powerful file system management tools all while staying within the asynchronous and promises territory.