Proversion

Upgrade versionable objects via immer produce

Install

npm i -S proversion

prerequisite immer 6.0.0

Usage

Provides a simple method to upgrade objects according to version rules.

Example

A simple upgrade of an object from version 1 to version 2.

const upgrades = proversion();
upgrades.add(2, (draft) => {
  draft.myAddedParam = true;
});

const original = { version: 1 };
const { applied, result } = upgrades.upgrade(original);

// Applied is an array of applied upgrades
console.log("applied", applied);
applied [ 2 ]

// result is the upgraded object
console.log("result", result);
result { version: 2, myAddedParam: true }

Note: Original is untouched thanks to Immer

Example 2

Multiple upgrades

const upgrades = proversion();
upgrades.add(2, (draft) => {
  draft.myAddedParam = true;
});
upgrades.add(3, (draft) => {
  draft.myAddedParam = false;
  draft.hi = 'There';
});
upgrades.add(4, (draft) => {
  draft.hi = 'Not today';
});
upgrades.add(5, (draft) => {
  draft.hi = draft.hi.toLowerCase();
});
upgrades.add(6, (draft) => {
  draft.hi = draft.hi.replace(/ /g, '_');
});

const original = { version: 1 };
const { applied, result } = upgrades.upgrade(original);

// Applied is an array of applied upgrades
console.log("applied", applied);
applied [ 2, 3, 4, 5, 6 ]

// result is the upgraded object
console.log("result", result);
result { version: 6, myAddedParam: false, hi: 'not_today' }

But notice what happens if we pass in a version 3 object.

const original = { version: 3, myAddedParam: false, hi: 'There' };
const { applied, result } = upgrades.upgrade(original);

// Applied is an array of applied upgrades
console.log("applied", applied);
applied [ 4, 5, 6 ]

// result is the upgraded object
console.log("result", result);
result { version: 6, myAddedParam: false, hi: 'not_today' }

we get the same result, but the version 1->2 and 2->3 upgrades are ignored.

Immer

Why use immer produce?

• Safe mutation of objects without affecting original
• Clean mutation API via draft object
• Converters are pure functions
• Immer is well maintained and has excellent documentation

License

MIT