rollbar-redux-middleware

Redux middleware that integrates with Rollbar. This middleware assumes the use of
actions that conform to the Flux Standard Action pattern. Essentially this means
that actions of the following form

``js
{
error: true,
payload: new Error()
}
`

are considered errors to be reported to Rollbar where the error is in the payload field.
We include the payload as well as the entire redux store state.
Additionally, we provide a configuration option to wrap all actions in a try/catch block rather than
simply using FSA style actions to denote errors.

__We provide mechanisms for easily santizing the store before logging (e.g. if you store access tokens in the redux store).__

Installation

Run npm install --save rollbar-redux-middleware.

Usage

Import rollbarMiddleware function from package:

`js
import rollbarMiddleware from 'rollbar-redux-middleware';
`

Import rollbar and configure:
`js
import rollbar from 'rollbar';
var Rollbar = new rollbar({accessToken: 'POST_CLIENT_ITEM_ACCESS_TOKEN'});
`

Create middleware in your store creator:
`js
export default function configureStore(initialState) {
const rollbarRedux = rollbarMiddleware(Rollbar);

return createStore(
rootReducer,
initialState,
applyMiddleware(rollbarRedux)
);
}
`

Wrapping actions in a try/catch

In order to wrap actions in a try/catch block, you must pass three parameters to the function
exported by this package:

`js
import rollbarMiddleware from 'rollbar-redux-middleware';
const rollbarRedux = rollbarMiddleware(Rollbar, keyPaths, true);
`

The second parameter is used for state sanitization described below. If you do not need or want that
functionality, simply pass an empty array, null, or the identity function as the second parameter.
The third parameter of true indicates that you do want to wrap actions in a try/catch block. The
first parameter is a configured Rollbar instance to use for reporting.

State sanitization

`js
{
user: {
credentials: {
token: 'ABC123',
name: 'Bob User'
},
(...)
},
billing: {
number: '1234 1234 1234 1234',
(...)
},
(...)
}
`

If you want to sanitize the state before sending to Rollbar, we provide two mechanisms. The first is
to include an array of keypaths that you wish to redact:

`js
const keyPaths = [
'billing.number',
'user.credentials.token'
]
`

Then just pass this as the second parameter to rollbarMiddleware:

`js
const rollbarRedux = rollbarMiddleware(Rollbar, keyPaths)
`

Alternatively, you can pass a function as the second argument to the rollbarMiddleware function.
It accepts current application state and should return a state that will be sent to Rollbar.

To sanitize the example state above the same as the given keypaths, the function provided should be
similar to:

`js
const stateSanitizer = function(state) {
// make sure you don't change state tree
const stateCopy = Object.assign({}, state);
// make sure you don't change billing object (by reference)
const billingCopy = Object.assign({}, stateCopy.billing);
// override number in billing copy
billingCopy.number = '**';
// pass billing copy to state copy
stateCopy.billing = billingCopy;

// similarly
const userCopy = Object.assign({}, stateCopy.user);
const credentialsCopy = Object.assign({}, userCopy.credentials)
credentialsCopy.token = '**'
userCopy.credentials = credentialsCopy;
stateCopy.user = userCopy;

// return sanitized state
return stateCopy;
}

export default function configureStore(initialState) {
const rollbarRedux = rollbarMiddleware(Rollbar, stateSanitizer);

return createStore(
rootReducer,
initialState,
applyMiddleware(rollbarRedux)
);
}
``