email-setup

Collection of utilities for checking email configuration settings.

Installation

npm install email-setup

Usage

SPF

SPF records exist as TXT records on a sending domain itself. spfSetup allows us to determine if a domain has a valid SPF record, and hasSPFSender allows us to detemine if a specific sender is allowed to send for the given domain. Note that hasSPFSender currently only support top level include detection, it does not currently resolve the SPF record to determine inclusion at a deeper level than the top level nor does it support IP based domain resolution querying at the moment.

spfSetup

spfSetup will return one of NOT_SETUP, INVALID or SETUP.

const { spfSetup } = require('email-setup');

let isSetup = await spfSetup('foo.com');

hasSPFSender

hasSPFSender returns either true or false depending on whether the sender explicitly exists at the top level of the SPF record.

const { hasSPFSender } = require('email-setup');

let isSetup = await hasSPFSender('foo.com', '_spf.google.com');

DKIM

DKIM records do not exist at any predetermined location, as such to check if a DKIM record is setup for a given system, we need to know the selector to look for the record under. Once we know that, we can determine whether a DKIM key has been setup for the given domain at the given selector.

hasDKIMRecordForSelector

hasDKIMRecordForSelector will return one of NOT_SETUP, INVALID or SETUP.

const { hasDKIMRecordForSelector } = require('email-setup');

let isSetup = await hasDKIMRecordForSelector('foo.com', 'google');

DMARC

DMARC records live as TXT records under _dmarc.<domain>, alongside whatever else a domain owner has published there. Only records that begin with the v=DMARC1 version tag are DMARC records; anything else under _dmarc is ignored.

A subdomain that publishes no record of its own is governed by the policy on its organizational domain — its sp tag, defaulting to p. So when no record is found on the domain itself, dmarcSetup makes one further lookup on the organizational domain, as RFC 7489 §6.6.3 requires. It never walks further up the tree than that.

dmarcSetup

dmarcSetup will return one of NOT_SETUP, INVALID or SETUP.

const { dmarcSetup } = require('email-setup');

let isSetup = await dmarcSetup('foo.com');

Publishing a new version

GH_TOKEN=xxx npx semantic-release --no-ci