enonic-fp

Enonic FP

Functional programming helpers for Enonic XP. This library covers a subset of the functionality. If there are other wrappers you need please raise an issue on Github, or file a pull request.

Requirements

1. Enonic 7 setup with Webpack
2. Individual Enonic client libraries installed (these are only wrappers)

Motivation

Currently this library just wraps an Either<Error, T> around the results from the standard Enonic XP libaries.

This gives us two things:

1. It forces the developer to handle the error case using fold
2. It allows us to pipe the results from one operation into the next using chain (or map). Chain expects another Either<Error, T> to be returned, and when the first left<Error> is returned the pipe will short circuit to the error case in fold.

This style of programming encourages us to write re-usable functions, that we can compose together using pipe.

Usage

Getting some content content by key.

import { Response, Request, Error } from "enonic-fp/lib/common";
import { Content, get as getContent } from 'enonic-fp/lib/content';
import { pipe } from "fp-ts/lib/pipeable";
import { fold } from "fp-ts/lib/Either";

export function get(req: Request): Response {
  return pipe(
    getContent({ 
      key: req.params.key 
    }),
    fold(
      (err: Error) => ({
        status: 500, // 500 = Internal Server Error
        contentType: 'application/json',
        body: err
      }),
      (content: Content) => ({
        status: 200, // 200 = Ok
        contentType: 'application/json',
        body: content
      })
    )
  );
}

Deleting some content by key. Deleting it first on the draft branch, and then publish it to the master branch.

import { Response, Request, Error } from "enonic-fp/lib/common";
import { remove, publish } from 'enonic-fp/lib/content';
import { run } from 'enonic-fp/lib/context';
import { pipe } from "fp-ts/lib/pipeable";
import { chain, fold } from "fp-ts/lib/Either";

function runInDraftContext<T>(f: () => T) {
  return run({ 
    branch: 'draft'
  }, f);
}

function publishToMaster(key) {
  return publish({
    keys: [key],
    sourceBranch: 'draft',
    targetBranch: 'master',
  });
}

const errorsKeyToStatus = {
  "InternalServerError": 500,
  "NotFoundError": 404,
  "PublishError": 500
};

function del(req: Request): Response {
  const key = req.params.key;

  return pipe(
    runInDraftContext(() => remove({ key })),
    chain(() => publishToMaster(key)),
    fold(
      (err: Error) => {
        return {
          status: errorsKeyToStatus[err.errorKey],
          contentType: 'application/json',
          body: err
        }
      },
      () => ({
        status: 204, // 204 = No content
        contentType: 'application/json',
        body: ''
      })
    )
  )
}

export { del as delete };

Building the project

npm run build