babel-plugin-redux-saga

NOTE: plugin is still in beta, so use it on your own risk. It does not work on React Native

Babel plugin for code instrumenting by extending redux-saga code fragments with additional meta-data. Meta-data contains information about code fragment location and other details, that could be consumed by developer tools or libraries. Adding the plugin improve logging for errors thrown in your sagas. Example of setup and demo are available here

Example

Error message without plugin

The above error occurred in task throwAnErrorSaga
    created by errorInCallAsyncSaga
    created by takeEvery(ACTION_ERROR_IN_CALL_ASYNC, errorInCallAsyncSaga)
    created by rootSaga

Error message with the plugin

The above error occurred in task throwAnErrorSaga  src/sagas/index.js?16
    created by errorInCallAsyncSaga  src/sagas/index.js?25
    created by takeEvery(ACTION_ERROR_IN_CALL_ASYNC, errorInCallAsyncSaga)
    created by rootSaga  src/sagas/index.js?78

Install

npm i --save-dev babel-plugin-redux-saga

Usage

1. with babel

    plugins: [
        'babel-plugin-redux-saga'
    ]

2. with webpack and babel-loader:

    loader: 'babel-loader',
    options: {
        plugins: [
            'babel-plugin-redux-saga'
        ]
    }

Options

All options are optional.

useAbsolutePath

• Type: Boolean
• Default: false

By default plugin generates relative to the current cwd file paths. But for some reasons absolute path may be required, for such cases configure useAbsolutePath option. For example, if option is not set:

    fileName: "path/to/filename.js"

But if useAbsolutePath is set to true,

    fileName: "/Users/name/git/project/path/to/filename.js"

How it transforms my code

Source:

// src/sagas/index.js
function* saga1(){
    yield call(foo, 1, 2, 3);
}

function* saga2(){
    yield 2;
}

Result:

function* saga1() {
    yield Object.defineProperty(call(foo, 1, 2, 3), "@@redux-saga/LOCATION", {
        value: {
            fileName: "src/sagas/index.js",
            lineNumber: 1,
            code: "call(foo, 1, 2, 3)"
        }
    })
}

Object.defineProperty(saga1, "@@redux-saga/LOCATION", {
  value: {
    fileName: "src/sagas/index.js",
    lineNumber: 1
  }
})
function* saga2() {
    yield 2;
}
Object.defineProperty(saga2, "@@redux-saga/LOCATION", {
  value: {
    fileName: "src/sagas/index.js",
    lineNumber: 5
  }
})

Problem solving

My source code became ugly, I can't read it anymore

Use source maps. It can't be set up in babel settings.

It also can be set up in your building tools setting. See webpack config for example.