neulab/tldr huggingface dataset:
Example usage for DNS-01 (Cloudflare API v4) (for example purposes only, do not use as-is)
certbot certonly --manual --preferred-challenges=dns --manual-auth-hook /path/to/dns/authenticator.sh --manual-cleanup-hook /path/to/dns/cleanup.sh -d secure.example.com
/path/to/dns/authenticator.sh
# Get your API key from https://www.cloudflare.com/a/account/my-account API_KEY="your-api-key" EMAIL="your.email@example.com"
# Strip only the top domain to get the zone id DOMAIN=$(expr match "$CERTBOT_DOMAIN" '.*\.\(.*\..*\)')
# Get the Cloudflare zone id ZONE_EXTRA_PARAMS="status=active&page=1&per_page=20&order=status&direction=desc&match=all" ZONE_ID=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$DOMAIN&$ZONE_EXTRA_PARAMS" \ -H     "X-Auth-Email: $EMAIL" \ -H     "X-Auth-Key: $API_KEY" \ -H     "Content-Type: application/json" | python -c "import sys,json;print(json.load(sys.stdin)['result'][0]['id'])")
# Create TXT record CREATE_DOMAIN="_acme-challenge.$CERTBOT_DOMAIN" RECORD_ID=$(curl -s -X POST "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records" \ -H     "X-Auth-Email: $EMAIL" \ -H     "X-Auth-Key: $API_KEY" \ -H     "Content-Type: application/json" \ --data '{"type":"TXT","name":"'"$CREATE_DOMAIN"'","content":"'"$CERTBOT_VALIDATION"'","ttl":120}' \ | python -c "import sys,json;print(json.load(sys.stdin)['result']['id'])") # Save info for cleanup if [ ! -d /tmp/CERTBOT_$CERTBOT_DOMAIN ];then mkdir -m 0700 /tmp/CERTBOT_$CERTBOT_DOMAIN fi echo $ZONE_ID > /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID echo $RECORD_ID > /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID
# Sleep to make sure the change has time to propagate over to DNS sleep 25
/path/to/dns/cleanup.sh
if [ -f /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID ]; then ZONE_ID=$(cat /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID) rm -f /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID fi
if [ -f /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID ]; then RECORD_ID=$(cat /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID) rm -f /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID fi
# Remove the challenge TXT record from the zone if [ -n "${ZONE_ID}" ]; then if [ -n "${RECORD_ID}" ]; then curl -s -X DELETE "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records/$RECORD_ID" \ -H "X-Auth-Email: $EMAIL" \ -H "X-Auth-Key: $API_KEY" \ -H "Content-Type: application/json" fi fi
Changing the ACME Server By default, Certbot uses Let's Encrypt's production server at https://acme-v02.api.letsencrypt.org/. You can tell Certbot to use a different CA by providing --server on the command line or in a configuration file with the URL of the server's ACME directory. For example, if you would like to use Let's Encrypt's staging server, you would add --server https://acme-staging-v02.api.letsencrypt.org/directory to the command line.
If you use --server to specify an ACME CA that implements the standardized version of the spec, you may be able to obtain a certificate for a wildcard domain. Some CAs (such as Let's Encrypt) require that domain validation for wildcard domains must be done through modifications to DNS records which means that the dns-01 challenge type must be used. To see a list of Certbot plugins that support this challenge type and how to use them, see plugins.
Lock Files When processing a validation Certbot writes a number of lock files on your system to prevent multiple instances from overwriting each other's changes. This means that by default two instances of Certbot will not be able to run in parallel.
Since the directories used by Certbot are configurable, Certbot will write a lock file for all of the directories it uses. This include Certbot's --work-dir, --logs-dir, and --config-dir. By default these are /var/lib/letsencrypt, /var/log/letsencrypt, and /etc/letsencrypt respectively. Additionally if you are using Certbot with Apache or nginx it will lock the configuration folder for that program, which are typically also in the /etc directory.
Note that these lock files will only prevent other instances of Certbot from using those directories, not other processes. If you'd like to run multiple instances of Certbot simultaneously you should specify different directories as the --work-dir, --logs-dir, and --config-dir for each instance of Certbot that you would like to run.
Configuration file Certbot accepts a global configuration file that applies its options to all invocations of Certbot. Certificate specific configuration choices should be set in the .conf files that can be found in /etc/letsencrypt/renewal.
By default no cli.ini file is created (though it may exist already if you installed Certbot via a package manager, for instance).  After creating one it is possible to specify the location of this configuration file with certbot --config cli.ini (or shorter -c cli.ini). An example configuration file is shown below:
# This is an example of the kind of things you can do in a configuration file. # All flags used by the client can be configured here. Run Certbot with # "--help" to learn more about the available options. # # Note that these options apply automatically to all use of Certbot for # obtaining or renewing certificates, so options specific to a single # certificate on a system with several certificates should not be placed # here.
# Use ECC for the private key key-type = ecdsa elliptic-curve = secp384r1
# Use a 4096 bit RSA key instead of 2048 rsa-key-size = 4096
# Uncomment and update to register with the specified e-mail address # email = foo@example.com
# Uncomment to use the standalone authenticator on port 443 # authenticator = standalone
# Uncomment to use the webroot authenticator. Replace webroot-path with the # path to the public_html / webroot folder being served by your web server. # authenticator = webroot # webroot-path = /usr/share/nginx/html
By default, the following locations are searched:
• /etc/letsencrypt/cli.ini
• $XDG_CONFIG_HOME/letsencrypt/cli.ini (or ~/.config/letsencrypt/cli.ini if $XDG_CONFIG_HOME is not set).
Since this configuration file applies to all invocations of certbot it is incorrect to list domains in it. Listing domains in cli.ini may prevent renewal from working.  Additionally due to how arguments in cli.ini are parsed, options which wish to not be set should not be listed. Options set to false will instead be read as being set to true by older versions of Certbot, since they have been listed in the config file.
Log Rotation By default certbot stores status logs in /var/log/letsencrypt. By default certbot will begin rotating logs once there are 1000 logs in the log directory.  Meaning that once 1000 files are in /var/log/letsencrypt Certbot will delete the oldest one to make room for new logs. The number of subsequent logs can be changed by passing the desired number to the command line flag --max-log-backups.
NOTE: Some distributions, including Debian and Ubuntu, disable certbot's internal log rotation in favor of a more traditional logrotate script. If you are using a distribution's packages and want to alter the log rotation, check /etc/logrotate.d/ for a certbot rotation script.
Certbot command-line options Certbot supports a lot of command line options. Here's the full list, from certbot --help all:
usage: certbot [SUBCOMMAND] [options] [-d DOMAIN] [-d DOMAIN] ...
Certbot can obtain and install HTTPS/TLS/SSL certificates.  By default, it will attempt to use a webserver both for obtaining and installing the certificate. The most common SUBCOMMANDS and flags are:
obtain, install, and renew certificates: (default) run   Obtain & install a certificate in your current webserver certonly        Obtain or renew a certificate, but do not install it renew           Renew all previously obtained certificates that are near expiry enhance         Add security enhancements to your existing configuration -d DOMAINS       Comma-separated list of domains to obtain a certificate for
--apache          Use the Apache plugin for authentication & installation --standalone      Run a standalone webserver for authentication --nginx           Use the Nginx plugin for authentication & installation --webroot         Place files in a server's webroot folder for authentication --manual          Obtain certificates interactively, or using shell script hooks
-n               Run non-interactively --test-cert       Obtain a test certificate from a staging server --dry-run         Test "renew" or "certonly" without saving any certificates to disk
manage certificates: certificates    Display information about certificates you have from Certbot revoke          Revoke a certificate (supply --cert-name or --cert-path) delete          Delete a certificate (supply --cert-name)
manage your account: register        Create an ACME account unregister      Deactivate an ACME account update_account  Update an ACME account --agree-tos       Agree to the ACME server's Subscriber Agreement -m EMAIL         Email address for important account notifications
automation: Flags for automating execution & other tweaks
--keep-until-expiring, --keep, --reinstall If the requested certificate matches an existing certificate, always keep the existing one until it is due for renewal (for the 'run' subcommand this means reinstall the existing certificate). (default: Ask) --expand              If an existing certificate is a strict subset of the requested names, always expand and replace it with the additional names. (default: Ask) --version             show program's version number and exit --force-renewal, --renew-by-default If a certificate already exists for the requested domains, renew it now, regardless of whether it is near expiry. (Often --keep-until-expiring is more appropriate). Also implies --expand. (default: False) --renew-with-new-domains If a certificate already exists for the requested certificate name but does not match the requested domains, renew it now, regardless of whether it is near expiry. (default: False) --reuse-key           When renewing, use the same private key as the existing certificate. (default: False) --allow-subset-of-names When performing domain validation, do not consider it a failure if authorizations can not be obtained for a strict subset of the requested domains. This may be useful for allowing renewals for multiple domains to succeed even if some domains no longer point at this system. This option cannot be used with --csr. (default: False) --agree-tos           Agree to the ACME Subscriber Agreement (default: Ask) --duplicate           Allow making a certificate lineage that duplicates an existing one (both can be renewed in parallel) (default: False) --os-packages-only    (certbot-auto only) install OS package dependencies and then stop (default: False) --no-self-upgrade     (certbot-auto only) prevent the certbot-auto script from upgrading itself to newer released versions (default: Upgrade automatically) --no-bootstrap        (certbot-auto only) prevent the certbot-auto script from installing OS-level dependencies (default: Prompt to install OS-wide dependencies, but exit if the user says 'No') --no-permissions-check (certbot-auto only) skip the check on the file system permissions of the certbot-auto script (default: False) -q, --quiet           Silence all output except errors. Useful for automation via cron. Implies --non-interactive. (default: False)
security: Security parameters & server settings
--rsa-key-size N      Size of the RSA key. (default: 2048) --key-type {rsa,ecdsa} Type of generated private key(Only *ONE* per invocation can be provided at this time) (default: rsa) --elliptic-curve N    The SECG elliptic curve name to use. Please see RFC 8446 for supported values. (default: secp256r1) --must-staple         Adds the OCSP Must Staple extension to the certificate. Autoconfigures OCSP Stapling for supported setups (Apache version >= 2.3.3 ). (default: False) --redirect            Automatically redirect all HTTP traffic to HTTPS for the newly authenticated vhost. (default: redirect enabled for install and run, disabled for enhance) --no-redirect         Do not automatically redirect all HTTP traffic to HTTPS for the newly authenticated vhost. (default: redirect enabled for install and run, disabled for enhance) --hsts                Add the Strict-Transport-Security header to every HTTP response. Forcing browser to always use SSL for the domain. Defends against SSL Stripping. (default: None) --uir                 Add the "Content-Security-Policy: upgrade-insecure- requests" header to every HTTP response. Forcing the browser to use https:// for every http:// resource. (default: None) --staple-ocsp         Enables OCSP Stapling. A valid OCSP response is stapled to the certificate that the server offers during TLS. (default: None) --strict-permissions  Require that all configuration files are owned by the current user; only needed if your config is somewhere unsafe like /tmp/ (default: False) --auto-hsts           Gradually increasing max-age value for HTTP Strict Transport Security security header (default: False)
testing: The following flags are meant for testing and integration purposes only.
--test-cert, --staging Use the staging server to obtain or revoke test (invalid) certificates; equivalent to --server https://acme-staging-v02.api.letsencrypt.org/directory (default: False) --debug               Show tracebacks in case of errors, and allow certbot- auto execution on experimental platforms (default: False) --no-verify-ssl       Disable verification of the ACME server's certificate. (default: False) --http-01-port HTTP01_PORT Port used in the http-01 challenge. This only affects the port Certbot listens on. A conforming ACME server will still attempt to connect on port 80. (default: 80) --http-01-address HTTP01_ADDRESS The address the server listens to during http-01 challenge. (default: ) --https-port HTTPS_PORT Port used to serve HTTPS. This affects which port Nginx will listen on after a LE certificate is installed. (default: 443) --break-my-certs      Be willing to replace or renew valid certificates with invalid (testing/staging) certificates (default: False)
paths: Flags for changing execution paths & servers
--cert-path CERT_PATH Path to where certificate is saved (with auth --csr), installed from, or revoked. (default: None) --key-path KEY_PATH   Path to private key for certificate installation or revocation (if account key is missing) (default: None) --fullchain-path FULLCHAIN_PATH Accompanying path to a full certificate chain (certificate plus chain). (default: None) --chain-path CHAIN_PATH Accompanying path to a certificate chain. (default: None) --config-dir CONFIG_DIR Configuration directory. (default: /etc/letsencrypt) --work-dir WORK_DIR   Working directory. (default: /var/lib/letsencrypt) --logs-dir LOGS_DIR   Logs directory. (default: /var/log/letsencrypt) --server SERVER       ACME Directory Resource URI. (default: https://acme-v02.api.letsencrypt.org/directory)
manage: Various subcommands and flags are available for managing your certificates:
certificates          List certificates managed by Certbot delete                Clean up all files related to a certificate renew                 Renew all certificates (or one specified with --cert- name) revoke                Revoke a certificate specified with --cert-path or --cert-name update_symlinks       Recreate symlinks in your /etc/letsencrypt/live/ directory
run: Options for obtaining & installing certificates
certonly: Options for modifying how a certificate is obtained
--csr CSR             Path to a Certificate Signing Request (CSR) in DER or PEM format. Currently --csr only works with the 'certonly' subcommand. (default: None)
renew: The 'renew' subcommand will attempt to renew all certificates (or more precisely, certificate lineages) you have previously obtained if they are close to expiry, and print a summary of the results. By default, 'renew' will reuse the options used to create obtain or most recently successfully renew each certificate lineage. You can try it with `--dry-run` first. For more fine-grained control, you can renew individual lineages with the `certonly` subcommand. Hooks are available to run commands before and after renewal; see https://certbot.eff.org/docs/using.html#renewal for more information on these.
--pre-hook PRE_HOOK   Command to be run in a shell before obtaining any certificates. Intended primarily for renewal, where it can be used to temporarily shut down a webserver that might conflict with the standalone plugin. This will only be called if a certificate is actually to be obtained/renewed. When renewing several certificates that have identical pre-hooks, only the first will be executed. (default: None) --post-hook POST_HOOK Command to be run in a shell after attempting to obtain/renew certificates. Can be used to deploy renewed certificates, or to restart any servers that were stopped by --pre-hook. This is only run if an attempt was made to obtain/renew a certificate. If multiple renewed certificates have identical post- hooks, only one will be run. (default: None) --deploy-hook DEPLOY_HOOK Command to be run in a shell once for each successfully issued certificate. For this command, the shell variable $RENEWED_LINEAGE will point to the config live subdirectory (for example, "/etc/letsencrypt/live/example.com") containing the new certificates and keys; the shell variable $RENEWED_DOMAINS will contain a space-delimited list of renewed certificate domains (for example, "example.com www.example.com" (default: None) --disable-hook-validation Ordinarily the commands specified for --pre- hook/--post-hook/--deploy-hook will be checked for validity, to see if the programs being run are in the $PATH, so that mistakes can be caught early, even when the hooks aren't being run just yet. The validation is rather simplistic and fails if you use more advanced shell constructs, so you can use this switch to disable it. (default: False) --no-directory-hooks  Disable running executables found in Certbot's hook directories during renewal. (default: False) --disable-renew-updates Disable automatic updates to your server configuration that would otherwise be done by the selected installer plugin, and triggered when the user executes "certbot renew", regardless of if the certificate is renewed. This setting does not apply to important TLS configuration updates. (default: False) --no-autorenew        Disable auto renewal of certificates. (default: True)
certificates: List certificates managed by Certbot
delete: Options for deleting a certificate
revoke: Options for revocation of certificates
--reason {unspecified,keycompromise,affiliationchanged,superseded,cessationofoperation} Specify reason for revoking certificate. (default: unspecified) --delete-after-revoke Delete certificates after revoking them, along with all previous and later versions of those certificates. (default: None) --no-delete-after-revoke Do not delete certificates after revoking them. This option should be used with caution because the 'renew' subcommand will attempt to renew undeleted revoked certificates. (default: None)
register: Options for account registration
--register-unsafely-without-email Specifying this flag enables registering an account with no email address. This is strongly discouraged, because you will be unable to receive notice about impending expiration or revocation of your certificates or problems with your Certbot installation that will lead to failure to renew. (default: False) -m EMAIL, --email EMAIL Email used for registration and recovery contact. Use comma to register multiple emails, ex: u1@example.com,u2@example.com. (default: Ask). --eff-email           Share your e-mail address with EFF (default: None) --no-eff-email        Don't share your e-mail address with EFF (default: None)
update_account: Options for account modification
unregister: Options for account deactivation.
--account ACCOUNT_ID  Account ID to use (default: None)
install: Options for modifying how a certificate is deployed
rollback: Options for rolling back server configuration changes
--checkpoints N       Revert configuration N number of checkpoints. (default: 1)
plugins: Options for the "plugins" subcommand
--init                Initialize plugins. (default: False) --prepare             Initialize and prepare plugins. (default: False) --authenticators      Limit to authenticator plugins only. (default: None) --installers          Limit to installer plugins only. (default: None)
update_symlinks: Recreates certificate and key symlinks in /etc/letsencrypt/live, if you changed them by hand or edited a renewal configuration file
enhance: Helps to harden the TLS configuration by adding security enhancements to already existing configuration.
plugins: Plugin Selection: Certbot client supports an extensible plugins architecture. See 'certbot plugins' for a list of all installed plugins and their names. You can force a particular plugin by setting options provided below. Running --help <plugin_name> will list flags specific to that plugin.
--configurator CONFIGURATOR Name of the plugin that is both an authenticator and an installer. Should not be used together with --authenticator or --installer. (default: Ask) -a AUTHENTICATOR, --authenticator AUTHENTICATOR Authenticator plugin name. (default: None) -i INSTALLER, --installer INSTALLER Installer plugin name (also used to find domains). (default: None) --apache              Obtain and install certificates using Apache (default: False) --nginx               Obtain and install certificates using Nginx (default: False) --standalone          Obtain certificates using a "standalone" webserver. (default: False) --manual              Provide laborious manual instructions for obtaining a certificate (default: False) --webroot             Obtain certificates by placing files in a webroot directory. (default: False) --dns-cloudflare      Obtain certificates using a DNS TXT record (if you are using Cloudflare for DNS). (default: False) --dns-cloudxns        Obtain certificates using a DNS TXT record (if you are using CloudXNS for DNS). (default: False) --dns-digitalocean    Obtain certificates using a DNS TXT record (if you are using DigitalOcean for DNS). (default: False) --dns-dnsimple        Obtain certificates using a DNS TXT record (if you are using DNSimple for DNS). (default: False) --dns-dnsmadeeasy     Obtain certificates using a DNS TXT record (if you are using DNS Made Easy for DNS). (default: False) --dns-gehirn          Obtain certificates using a DNS TXT record (if you are using Gehirn Infrastructure Service for DNS). (default: False) --dns-google          Obtain certificates using a DNS TXT record (if you are using Google Cloud DNS). (default: False) --dns-linode          Obtain certificates using a DNS TXT record (if you are using Linode for DNS). (default: False) --dns-luadns          Obtain certificates using a DNS TXT record (if you are using LuaDNS for DNS). (default: False) --dns-nsone           Obtain certificates using a DNS TXT record (if you are using NS1 for DNS). (default: False) --dns-ovh             Obtain certificates using a DNS TXT record (if you are using OVH for DNS). (default: False) --dns-rfc2136         Obtain certificates using a DNS TXT record (if you are using BIND for DNS). (default: False) --dns-route53         Obtain certificates using a DNS TXT record (if you are using Route53 for DNS). (default: False) --dns-sakuracloud     Obtain certificates using a DNS TXT record (if you are using Sakura Cloud for DNS). (default: False)
apache: Apache Web Server plugin (Please note that the default values of the Apache plugin options change depending on the operating system Certbot is run on.)
--apache-enmod APACHE_ENMOD Path to the Apache 'a2enmod' binary (default: None) --apache-dismod APACHE_DISMOD Path to the Apache 'a2dismod' binary (default: None) --apache-le-vhost-ext APACHE_LE_VHOST_EXT SSL vhost configuration extension (default: -le- ssl.conf) --apache-server-root APACHE_SERVER_ROOT Apache server root directory (default: /etc/apache2) --apache-vhost-root APACHE_VHOST_ROOT Apache server VirtualHost configuration root (default: None) --apache-logs-root APACHE_LOGS_ROOT Apache server logs directory (default: /var/log/apache2) --apache-challenge-location APACHE_CHALLENGE_LOCATION Directory path for challenge configuration (default: /etc/apache2) --apache-handle-modules APACHE_HANDLE_MODULES Let installer handle enabling required modules for you (Only Ubuntu/Debian currently) (default: False) --apache-handle-sites APACHE_HANDLE_SITES Let installer handle enabling sites for you (Only Ubuntu/Debian currently) (default: False) --apache-ctl APACHE_CTL Full path to Apache control script (default: apache2ctl) --apache-bin APACHE_BIN Full path to apache2/httpd binary (default: None)
dns-cloudflare: Obtain certificates using a DNS TXT record (if you are using Cloudflare for DNS).
--dns-cloudflare-propagation-seconds DNS_CLOUDFLARE_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 10) --dns-cloudflare-credentials DNS_CLOUDFLARE_CREDENTIALS Cloudflare credentials INI file. (default: None)
dns-cloudxns: Obtain certificates using a DNS TXT record (if you are using CloudXNS for DNS).
--dns-cloudxns-propagation-seconds DNS_CLOUDXNS_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 30) --dns-cloudxns-credentials DNS_CLOUDXNS_CREDENTIALS CloudXNS credentials INI file. (default: None)
dns-digitalocean: Obtain certs using a DNS TXT record (if you are using DigitalOcean for DNS).
--dns-digitalocean-propagation-seconds DNS_DIGITALOCEAN_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 10) --dns-digitalocean-credentials DNS_DIGITALOCEAN_CREDENTIALS DigitalOcean credentials INI file. (default: None)
dns-dnsimple: Obtain certificates using a DNS TXT record (if you are using DNSimple for DNS).
--dns-dnsimple-propagation-seconds DNS_DNSIMPLE_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 30) --dns-dnsimple-credentials DNS_DNSIMPLE_CREDENTIALS DNSimple credentials INI file. (default: None)
dns-dnsmadeeasy: Obtain certificates using a DNS TXT record (if you are using DNS Made Easy for DNS).
--dns-dnsmadeeasy-propagation-seconds DNS_DNSMADEEASY_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 60) --dns-dnsmadeeasy-credentials DNS_DNSMADEEASY_CREDENTIALS DNS Made Easy credentials INI file. (default: None)
dns-gehirn: Obtain certificates using a DNS TXT record (if you are using Gehirn Infrastructure Service for DNS).
--dns-gehirn-propagation-seconds DNS_GEHIRN_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 30) --dns-gehirn-credentials DNS_GEHIRN_CREDENTIALS Gehirn Infrastructure Service credentials file. (default: None)
dns-google: Obtain certificates using a DNS TXT record (if you are using Google Cloud DNS for DNS).
--dns-google-propagation-seconds DNS_GOOGLE_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 60) --dns-google-credentials DNS_GOOGLE_CREDENTIALS Path to Google Cloud DNS service account JSON file. (See https://developers.google.com/identity/protocols/ OAuth2ServiceAccount#creatinganaccount forinformation about creating a service account and https://cloud.google.com/dns/access- control#permissions_and_roles for information about therequired permissions.) (default: None)
dns-linode: Obtain certs using a DNS TXT record (if you are using Linode for DNS).
--dns-linode-propagation-seconds DNS_LINODE_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 120) --dns-linode-credentials DNS_LINODE_CREDENTIALS Linode credentials INI file. (default: None)
dns-luadns: Obtain certificates using a DNS TXT record (if you are using LuaDNS for DNS).
--dns-luadns-propagation-seconds DNS_LUADNS_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 30) --dns-luadns-credentials DNS_LUADNS_CREDENTIALS LuaDNS credentials INI file. (default: None)
dns-nsone: Obtain certificates using a DNS TXT record (if you are using NS1 for DNS).
--dns-nsone-propagation-seconds DNS_NSONE_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 30) --dns-nsone-credentials DNS_NSONE_CREDENTIALS NS1 credentials file. (default: None)
dns-ovh: Obtain certificates using a DNS TXT record (if you are using OVH for DNS).
--dns-ovh-propagation-seconds DNS_OVH_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 30) --dns-ovh-credentials DNS_OVH_CREDENTIALS OVH credentials INI file. (default: None)
dns-rfc2136: Obtain certificates using a DNS TXT record (if you are using BIND for DNS).
--dns-rfc2136-propagation-seconds DNS_RFC2136_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 60) --dns-rfc2136-credentials DNS_RFC2136_CREDENTIALS RFC 2136 credentials INI file. (default: None)
dns-route53: Obtain certificates using a DNS TXT record (if you are using AWS Route53 for DNS).
--dns-route53-propagation-seconds DNS_ROUTE53_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 10)
dns-sakuracloud: Obtain certificates using a DNS TXT record (if you are using Sakura Cloud for DNS).
--dns-sakuracloud-propagation-seconds DNS_SAKURACLOUD_PROPAGATION_SECONDS The number of seconds to wait for DNS to propagate before asking the ACME server to verify the DNS record. (default: 90) --dns-sakuracloud-credentials DNS_SAKURACLOUD_CREDENTIALS Sakura Cloud credentials file. (default: None)
manual: Authenticate through manual configuration or custom shell scripts. When using shell scripts, an authenticator script must be provided. The environment variables available to this script depend on the type of challenge. $CERTBOT_DOMAIN will always contain the domain being authenticated. For HTTP-01 and DNS-01, $CERTBOT_VALIDATION is the validation string, and $CERTBOT_TOKEN is the filename of the resource requested when performing an HTTP-01 challenge. An additional cleanup script can also be provided and can use the additional variable $CERTBOT_AUTH_OUTPUT which contains the stdout output from the auth script. For both authenticator and cleanup script, on HTTP-01 and DNS-01 challenges, $CERTBOT_REMAINING_CHALLENGES will be equal to the number of challenges that remain after the current one, and $CERTBOT_ALL_DOMAINS contains a comma-separated list of all domains that are challenged for the current certificate.
--manual-auth-hook MANUAL_AUTH_HOOK Path or command to execute for the authentication script (default: None) --manual-cleanup-hook MANUAL_CLEANUP_HOOK Path or command to execute for the cleanup script (default: None)
nginx: Nginx Web Server plugin
--nginx-server-root NGINX_SERVER_ROOT Nginx server root directory. (default: /etc/nginx or /usr/local/etc/nginx) --nginx-ctl NGINX_CTL Path to the 'nginx' binary, used for 'configtest' and retrieving nginx version number. (default: nginx) --nginx-sleep-seconds NGINX_SLEEP_SECONDS Number of seconds to wait for nginx configuration changes to apply when reloading. (default: 1)
null: Null Installer
standalone: Spin up a temporary webserver
webroot: Place files in webroot directory
--webroot-path WEBROOT_PATH, -w WEBROOT_PATH public_html / webroot path. This can be specified multiple times to handle different domains; each domain will have the webroot path that preceded it. For instance: `-w /var/www/example -d example.com -d www.example.com -w /var/www/thing -d thing.net -d m.thing.net` (default: Ask) --webroot-map WEBROOT_MAP JSON dictionary mapping domains to webroot paths; this implies -d for each entry. You may need to escape this from your shell. E.g.: --webroot-map '{"eg1.is,m.eg1.is":"/www/eg1/", "eg2.is":"/www/eg2"}' This option is merged with, but takes precedence over, -w / -d entries. At present, if you put webroot-map in a config file, it needs to be on a single line, like: webroot-map = {"example.com":"/var/www"}. (default: {})
Getting help If you're having problems, we recommend posting on the Let's Encrypt Community Forum.
If you find a bug in the software, please do report it in our issue tracker. Remember to give us as much information as possible:
• copy and paste exact command line used and the output (though mind that the latter might include some personally identifiable information, including your email and domains)
• copy and paste logs from /var/log/letsencrypt (though mind they also might contain personally identifiable information)
• copy and paste certbot --version output
• your operating system, including specific version
• specify which installation method you've chosen
Table of Contents • Getting Started
• Running a local copy of the client
• Find issues to work on
• Testing
• Running automated unit tests
• Running automated integration tests
• Running manual integration tests
• Running tests in CI
• Code components and layout
• Plugin-architecture
• Authenticators
• Installer
• Installer Development
• Writing your own plugin
• Writing your own plugin snap
• Coding style
• Use certbot.compat.os instead of os
• Mypy type annotations
• Submitting a pull request
• Asking for help
• Building the Certbot and DNS plugin snaps
• Updating certbot-auto and letsencrypt-auto
• Updating the scripts
• Building letsencrypt-auto-source/letsencrypt-auto
• Opening a PR
• Updating the documentation
• Running the client with Docker
Getting Started Certbot has the same system requirements when set up for development. While the section below will help you install Certbot and its dependencies, Certbot needs to be run on a UNIX-like OS so if you're using Windows, you'll need to set up a (virtual) machine running an OS such as Linux and continue with these instructions on that UNIX-like OS.
Running a local copy of the client Running the client in developer mode from your local tree is a little different than running Certbot as a user. To get set up, clone our git repository by running:
git clone https://github.com/certbot/certbot
If you're on macOS, we recommend you skip the rest of this section and instead run Certbot in Docker. You can find instructions for how to do this here. If you're running on Linux, you can run the following commands to install dependencies and set up a virtual environment where you can run Certbot.
Install the OS system dependencies required to run Certbot.
# For APT-based distributions (e.g. Debian, Ubuntu ...) sudo apt update sudo apt install python3-dev python3-venv gcc libaugeas0 libssl-dev \ libffi-dev ca-certificates openssl # For RPM-based distributions (e.g. Fedora, CentOS ...) # NB1: old distributions will use yum instead of dnf # NB2: RHEL-based distributions use python3X-devel instead of python3-devel (e.g. python36-devel) sudo dnf install python3-devel gcc augeas-libs openssl-devel libffi-devel \ redhat-rpm-config ca-certificates openssl
Set up the Python virtual environment that will host your Certbot local instance.
cd certbot python tools/venv3.py
NOTE: You may need to repeat this when Certbot's dependencies change or when a new plugin is introduced.
You can now run the copy of Certbot from git either by executing venv3/bin/certbot, or by activating the virtual environment. You can do the latter by running:
source venv3/bin/activate
After running this command, certbot and development tools like ipdb, ipython, pytest, and tox are available in the shell where you ran the command. These tools are installed in the virtual environment and are kept separate from your global Python installation. This works by setting environment variables so the right executables are found and Python can pull in the versions of various packages needed by Certbot.  More information can be found in the virtualenv docs.
Find issues to work on You can find the open issues in the github issue tracker.  Comparatively easy ones are marked good first issue.  If you're starting work on something, post a comment to let others know and seek feedback on your plan where appropriate.
Once you've got a working branch, you can open a pull request.  All changes in your pull request must have thorough unit test coverage, pass our tests, and be compliant with the coding style.
Testing You can test your code in several ways:
• running the automated unit tests,
• running the automated integration tests
• running an ad hoc manual integration test
Running automated unit tests When you are working in a file foo.py, there should also be a file foo_test.py either in the same directory as foo.py or in the tests subdirectory (if there isn't, make one). While you are working on your code and tests, run python foo_test.py to run the relevant tests.
For debugging, we recommend putting import ipdb; ipdb.set_trace() statements inside the source code.
Once you are done with your code changes, and the tests in foo_test.py pass, run all of the unit tests for Certbot and check for coverage with tox -e py3-cover. You should then check for code style with tox -e lint (all files) or pylint --rcfile=.pylintrc path/to/file.py (single file at a time).
Once all of the above is successful, you may run the full test suite using tox --skip-missing-interpreters. We recommend running the commands above first, because running all tests like this is very slow, and the large amount of output can make it hard to find specific failures when they happen.
WARNING: The full test suite may attempt to modify your system's Apache config if your user has sudo permissions, so it should not be run on a production Apache server.
Running automated integration tests Generally it is sufficient to open a pull request and let Github and Azure Pipelines run integration tests for you. However, you may want to run them locally before submitting your pull request. You need Docker and docker-compose installed and working.
The tox environment integration will setup Pebble, the Let's Encrypt ACME CA server for integration testing, then launch the Certbot integration tests.
With a user allowed to access your local Docker daemon, run:
tox -e integration
Tests will be run using pytest. A test report and a code coverage report will be displayed at the end of the integration tests execution.
Running manual integration tests You can also manually execute Certbot against a local instance of the Pebble ACME server.  This is useful to verify that the modifications done to the code makes Certbot behave as expected.
To do so you need:
• Docker installed, and a user with access to the Docker client,
• an available local copy of Certbot.
The virtual environment set up with python tools/venv3.py contains two CLI tools that can be used once the virtual environment is activated:
run_acme_server
• Starts a local instance of Pebble and runs in the foreground printing its logs.
• Press CTRL+C to stop this instance.
• This instance is configured to validate challenges against certbot executed locally.
NOTE: Some options are available to tweak the local ACME server. You can execute run_acme_server --help to see the inline help of the run_acme_server tool.
certbot_test [ARGS...]
• Execute certbot with the provided arguments and other arguments useful for testing purposes, such as: verbose output, full tracebacks in case Certbot crashes, etc.
• Execution is preconfigured to interact with the Pebble CA started with run_acme_server.
• Any arguments can be passed as they would be to Certbot (eg. certbot_test certonly -d test.example.com).
Here is a typical workflow to verify that Certbot successfully issued a certificate using an HTTP-01 challenge on a machine with Python 3:
python tools/venv3.py source venv3/bin/activate run_acme_server & certbot_test certonly --standalone -d test.example.com # To stop Pebble, launch `fg` to get back the background job, then press CTRL+C
Running tests in CI Certbot uses Azure Pipelines to run continuous integration tests. If you are using our Azure setup, a branch whose name starts with test- will run all tests on that branch.
Code components and layout The following components of the Certbot repository are distributed to users:
acme   contains all protocol specific code
certbot main client code
certbot-apache and certbot-nginx client code to configure specific web servers
certbot-dns-* client code to configure DNS providers
certbot-auto and letsencrypt-auto shell scripts to install Certbot and its dependencies on UNIX systems
windows installer Installs Certbot on Windows and is built using the files in windows-installer/
Plugin-architecture Certbot has a plugin architecture to facilitate support for different webservers, other TLS servers, and operating systems.  The interfaces available for plugins to implement are defined in interfaces.py and plugins/common.py.
The main two plugin interfaces are IAuthenticator, which implements various ways of proving domain control to a certificate authority, and IInstaller, which configures a server to use a certificate once it is issued. Some plugins, like the built-in Apache and Nginx plugins, implement both interfaces and perform both tasks. Others, like the built-in Standalone authenticator, implement just one interface.
There are also IDisplay plugins, which can change how prompts are displayed to a user.
Authenticators Authenticators are plugins that prove control of a domain name by solving a challenge provided by the ACME server. ACME currently defines several types of challenges: HTTP, TLS-ALPN, and DNS, represented by classes in acme.challenges.  An authenticator plugin should implement support for at least one challenge type.
An Authenticator indicates which challenges it supports by implementing get_chall_pref(domain) to return a sorted list of challenge types in preference order.
An Authenticator must also implement perform(achalls), which "performs" a list of challenges by, for instance, provisioning a file on an HTTP server, or setting a TXT record in DNS. Once all challenges have succeeded or failed, Certbot will call the plugin's cleanup(achalls) method to remove any files or DNS records that were needed only during authentication.
Installer Installers plugins exist to actually setup the certificate in a server, possibly tweak the security configuration to make it more correct and secure (Fix some mixed content problems, turn on HSTS, redirect to HTTPS, etc).  Installer plugins tell the main client about their abilities to do the latter via the supported_enhancements() call. We currently have two Installers in the tree, the ApacheConfigurator. and the NginxConfigurator.  External projects have made some progress toward support for IIS, Icecast and Plesk.
Installers and Authenticators will oftentimes be the same class/object (because for instance both tasks can be performed by a webserver like nginx) though this is not always the case (the standalone plugin is an authenticator that listens on port 80, but it cannot install certs; a postfix plugin would be an installer but not an authenticator).
Installers and Authenticators are kept separate because it should be possible to use the StandaloneAuthenticator (it sets up its own Python server to perform challenges) with a program that cannot solve challenges itself (Such as MTA installers).
Installer Development There are a few existing classes that may be beneficial while developing a new IInstaller.  Installers aimed to reconfigure UNIX servers may use Augeas for configuration parsing and can inherit from AugeasConfigurator class to handle much of the interface. Installers that are unable to use Augeas may still find the Reverter class helpful in handling configuration checkpoints and rollback.
Writing your own plugin NOTE: The Certbot team is not currently accepting any new DNS plugins because we want to rethink our approach to the challenge and resolve some issues like #6464, #6503, and #6504 first.
In the meantime, you're welcome to release it as a third-party plugin. See certbot-dns-ispconfig for one example of that.
Certbot client supports dynamic discovery of plugins through the setuptools entry points using the certbot.plugins group. This way you can, for example, create a custom implementation of IAuthenticator or the IInstaller without having to merge it with the core upstream source code. An example is provided in examples/plugins/ directory.
While developing, you can install your plugin into a Certbot development virtualenv like this:
. venv/bin/activate pip install -e examples/plugins/ certbot_test plugins
Your plugin should show up in the output of the last command. If not, it was not installed properly.
Once you've finished your plugin and published it, you can have your users install it system-wide with pip install. Note that this will only work for users who have Certbot installed from OS packages or via pip.
Writing your own plugin snap If you'd like your plugin to be used alongside the Certbot snap, you will also have to publish your plugin as a snap. Plugin snaps are regular confined snaps, but normally do not provide any "apps" themselves. Plugin snaps export loadable Python modules to the Certbot snap.
When the Certbot snap runs, it will use its version of Python and prefer Python modules contained in its own snap over modules contained in external snaps. This means that your snap doesn't have to contain things like an extra copy of Python, Certbot, or their dependencies, but also that if you need a different version of a dependency than is already installed in the Certbot snap, the Certbot snap will have to be updated.
Certbot plugin snaps expose their Python modules to the Certbot snap via a snap content interface where certbot-1 is the value for the content attribute. The Certbot snap only uses this to find the names of connected plugin snaps and it expects to find the Python modules to be loaded under lib/python3.8/site-packages/ in the plugin snap. This location is the default when using the core20 base snap and the python snapcraft plugin.
The Certbot snap also provides a separate content interface which you can use to get metadata about the Certbot snap using the content identifier metadata-1.
The script used to generate the snapcraft.yaml files for our own externally snapped plugins can be found at https://github.com/certbot/certbot/blob/master/tools/snap/generate_dnsplugins_snapcraft.sh.
For more information on building externally snapped plugins, see the section on Building the Certbot and DNS plugin snaps.
Once you have created your own snap, if you have the snap file locally, it can be installed for use with Certbot by running:
snap install --classic certbot snap set certbot trust-plugin-with-root=ok snap install --dangerous your-snap-filename.snap sudo snap connect certbot:plugin your-snap-name sudo /snap/bin/certbot plugins
If everything worked, the last command should list your plugin in the list of plugins found by Certbot. Once your snap is published to the snap store, it will be installable through the name of the snap on the snap store without the --dangerous flag. If you are also using Certbot's metadata interface, you can run sudo snap connect your-snap-name:your-plug-name-for-metadata certbot:certbot-metadata to connect your snap to it.
Coding style Please:
1. Be consistent with the rest of the code.
2. Read PEP 8 - Style Guide for Python Code.
3. Follow the Google Python Style Guide, with the exception that we use Sphinx-style documentation:
def foo(arg): """Short description.
:param int arg: Some number.
:returns: Argument :rtype: int
""" return arg
4. Remember to use pylint.
5. You may consider installing a plugin for editorconfig in your editor to prevent some linting warnings.
6. Please avoid unittest.assertTrue or unittest.assertFalse when possible, and use assertEqual or more specific assert. They give better messages when it's failing, and are generally more correct.
Use certbot.compat.os instead of os Python's standard library os module lacks full support for several Windows security features about file permissions (eg. DACLs). However several files handled by Certbot (eg. private keys) need strongly restricted access on both Linux and Windows.