Dryify.js

A utility module to reduce your LOC by abstracting the most repeated sequences into single function calls.

Dryify is installable via:

• npm: npm install dryify --save

Dryify provides a few functions that attempt to abstract the most common patterns for retrieving, changing and passing in JSON objects.

Documentation

Changing functions

• optionify

Working with JSON objects

• getval
• setval
• traverse

Changing functions

---

optionify(fn, [orderedParamNames])

Takes a single argument, a function, and returns a wrapper of the same function that can take the arguments in the form of an 'options' object.

This is a case of 'changing the function to suit the data' (usually the data is changed to suit the function). The returned function can potentially be cached for later use. This also allows the possibility of eliminating some of the steps required to massage data to fit a method, and improves readability of the supplied arguments.

Uses regex to extract the argument names if they are not explicitly supplied.

Arguments

• fn (function) the function to convert into an equivalent function that accepts a single options object instead of multiple parameter arguments
• orderedParamNames (Optional array) an array of strings specifying the names (and ordering) of acceptable keys as parameters. Usually used if a function has been minified and the options object keys don't match the real parameter names, in which case we rely on ordering

Examples

dryify.optionify( parseInt, ['string'] )({ string: "13579" })
// Evaluates to 13579 (integer)

var optionifiedFn = dryify.optionify(
  function simpleFn(arg1, arg2, arg3) {
    return (arg1 || "") + (arg2 || "") + (arg3 || "");
  },
  ['mapper1', 'mapper2', 'mapper3']
);

optionifiedFn({
  mapper3: "world",
  mapper1: "hello, "
})
// Evaluates to "hello, world"

---

Working with JSON objects

---

getval(startingReference, jsonPath, [ifNull])

Allows the elegant retrieval of a JSON value using a starting reference, an evaluated string, and a configurable return value or behaviour when not found.

Saves you from the repitition of multiple levels of 'if... exists...'

Arguments

• startingReference (object) the referenced JS object

• jsonPath (string) a string that evaluates to a path deep into the object, saving you from having to check if it exists at each step of the path.

                  The convention uses strings like:
  

  "[3].key1[2].key2"
  "key1.key2[1]"

                  etc...

• ifNull (Optional [any type, function]) if the path is not found, returns this if not a function, or if a function, calls the function

Examples

dryify.getval(
  {
    // deep object
  },
  "[1].key1[0].key2[0].key3[0].foo"
)
// Evaluates to the value of @foo

---

setval(startingReference, jsonPath, value, [ifPathNotFound])

Allows the elegant setting of a JSON value using a starting reference, an evaluated string, and configurable behaviour when not found.

Saves you from the repitition of multiple levels of 'if... exists...'

Arguments

• startingReference (object) the referenced JS object

• jsonPath (string) a string that evaluates to a path deep into the object, saving you from having to check if it exists at each step of the path.

                  The convention uses strings like:
  

  "[3].key1[2].key2"
  "key1.key2[1]"

                  etc...

• value ([any]) the value to assign

• ifPathNotFound (Optional [boolean, function]) defaults to false. If the path or part of the path is not found, should the path be created automatically.

                  If a function is passed, this function is executed with
                  the @startingReference and @value arguments passed in.
  

Examples

dryify.setval( [object], "[1].key1[0].key2[0].key3[0].foo", 13579, true)
// @object (path) => .foo === 13579

dryify.setval(
  [], // the starting object
  "[2].key1[0]", // path
  "foovalue", // the value to assign
  // the function to execute if the path does not exist at some point
  function(
    startingReference, // the starting object from before
    value // the value desired
  ) {

    // perform some arbitrary operations here

    return startingReference; // what to return up the chain
  }
)

---

traverse(json, callback)

Traverses an entire JSON object hierarchically, iterating over every key and value referentially.

Arguments

• json (object) the JSON to traverse
• callback (function) a function that passes in the value, index and path of the traversal as the arguments (v, i, path). The callback function now leaves the original value in place by default.

Examples

dryify.traverse(json, function(v, i, path) {

  // Your changes here

  return v; // the value to assign
});

---

noConflict()

Changes the value of dryify back to its original value, returning a reference to the dryify object.