What is acme-client?
The acme-client npm package is a client library for the ACME (Automated Certificate Management Environment) protocol, which is used to automate the process of obtaining and renewing SSL/TLS certificates. It is commonly used with Let's Encrypt, a free, automated, and open Certificate Authority.
What are acme-client's main functionalities?
Creating an ACME client instance
This code demonstrates how to create an instance of the ACME client. The client is configured to use Let's Encrypt's production directory and a newly generated account key.
const acme = require('acme-client');
const client = new acme.Client({
directoryUrl: acme.directory.letsencrypt.production,
accountKey: await acme.forge.createPrivateKey()
});
Creating a new account
This code shows how to create a new account with the ACME server. It agrees to the terms of service and provides a contact email.
await client.createAccount({
termsOfServiceAgreed: true,
contact: ['mailto:admin@example.com']
});
Generating a certificate
This code demonstrates how to generate a certificate signing request (CSR) and then use the ACME client to automatically obtain a certificate for the domain 'example.com'.
const [key, csr] = await acme.forge.createCsr({
commonName: 'example.com'
});
const cert = await client.auto({
csr,
email: 'admin@example.com',
termsOfServiceAgreed: true
});
Renewing a certificate
This code shows how to renew an existing certificate using the ACME client. It requires the existing certificate and CSR.
const renewedCert = await client.renewCertificate({
certificate: existingCert,
csr: existingCsr
});
Other packages similar to acme-client
greenlock
Greenlock is another ACME client for Node.js that simplifies the process of obtaining and renewing SSL/TLS certificates from Let's Encrypt. It provides a higher-level API compared to acme-client and includes additional features like automatic renewal and integration with various web servers.
letsencrypt
The letsencrypt package is a Node.js client for Let's Encrypt. It is designed to be simple and easy to use, providing basic functionality for obtaining and renewing certificates. It is less feature-rich compared to acme-client but can be a good choice for straightforward use cases.
certbot
Certbot is a popular ACME client developed by the Electronic Frontier Foundation (EFF). While it is not a Node.js package, it is widely used for obtaining and renewing Let's Encrypt certificates. It offers a comprehensive set of features and is highly configurable, making it suitable for a variety of environments.
acme-client
A simple and unopinionated ACME client.
This module is written to handle communication with a Boulder/Let's Encrypt-style ACME API.
ACME specification: https://github.com/ietf-wg-acme/acme/blob/master/draft-ietf-acme-acme.md
Information on how the Boulder/Let's Encrypt API diverges from the ACME spec:
https://github.com/letsencrypt/boulder/blob/master/docs/acme-divergences.md
ACME compatibility
acme-client | API | Style |
---|
v2.x | ACMEv2 | Promise |
v1.x | ACMEv1 | callback |
Installation
acme-client
requires OpenSSL to be installed and available in $PATH
.
$ npm install acme-client
$ openssl version
Usage
const acme = require('acme-client');
const accountPrivateKey = '<PEM encoded private key>';
const client = new acme.Client({
directoryUrl: acme.directory.letsencrypt.staging,
accountKey: accountPrivateKey
});
Directory URLs
acme.directory.letsencrypt.staging;
acme.directory.letsencrypt.production;
Auto mode
For convenience an auto()
method is included in the client that takes a single config object.
This method will handle the entire process of getting a certificate for one or multiple domains.
A full example can be found at examples/auto.js.
Documentation: docs/client.md#AcmeClient+auto
Example
const autoOpts = {
csr: '<PEM encoded CSR>',
email: 'test@example.com',
termsOfServiceAgreed: true,
challengeCreateFn: async (authz, challenge, keyAuthorization) => {},
challengeRemoveFn: async (authz, challenge, keyAuthorization) => {}
}
const certificate = await client.auto(autoOpts);
OpenSSL utils
Some OpenSSL utility methods are included for creating keys and Certificate Signing Requests, exposed through acme.openssl
.
Documentation: docs/openssl.md
Example
const privateKey = await acme.openssl.createPrivateKey();
const [certificateKey, certificateCsr] = await acme.openssl.createCsr({
commonName: '*.example.com',
altNames: ['example.com']
})
API
For more fine-grained control you can interact with the ACME API using the methods documented below.
A full example can be found at examples/api.js.
Documentation: docs/client.md
Example
const account = await client.createAccount({
termsOfServiceAgreed: true,
contact: ['mailto:test@example.com']
});
const order = await client.createOrder({
identifiers: [
{ type: 'dns', value: 'example.com' },
{ type: 'dns', value: '*.example.com' }
]
});
Debugging
acme-client
uses debug for debugging which can be enabled by running
DEBUG=acme-client node index.js
License
MIT