get-zones (was “convertzone”)

DNSControl has a stand-alone utility that will contact a provider, download the records of one or more zones, and output them to a file in a variety of formats.

get-zones relies on command line parameters and creds.json exclusively. It does not use dnsconfig.js. This is to assist bootstrapping a new system.

Use case 1: Bootstrapping a new system

If you are moving a DNS zone from a provider to DNSControl, this command will do most of the work for you by downloading the records and writing them out in dnsconfig.js format. It is intended to be “a decent first draft”, only requiring minimal editing.

Use --format=djs or --format=js (djs is recommended; djs format is a comma-leading formatting style for lists, sometimes also called Haskell style).

Minor editing is required. Not all record formats are supported. SOA records are commented out, since most providers do not support it. BIND supports it, but requires the data to be entered as meta data.

The NAMESERVER() command is generated commented out. This is usually not needed as DNSControl can get more accurate information via the API. Remove the comments only to override the DNS service provider.

Use case 2: Generating BIND ZONE files

The --format=zone generates BIND-style zonefiles. Pseudo records not supported by BIND are generated as comments.

This format is useful when moving zonedata between providers, since the format is relatively universal.

This format is also useful for generating backups of DNS zones. Unlike making a backup of the dnsconfig.js, this is the raw records, which may be useful.

Use case 3: TAB separated values

The goal of --format=tsv is to provide a high-fidelity format that is easy enough to parse with awk.

Use case 4: List zones

If a provider supports it, --format=nameonly lists the names of the zones at the provider.

Syntax

dnscontrol get-zones [command options] credkey provider zone [...]

--creds value   Provider credentials JSON file (default: "creds.json")
--format value  Output format: js djs zone tsv nameonly (default: "zone")
--out value     Instead of stdout, write to this file
--ttl value     Default TTL (0 picks the zone's most common TTL) (default: 0)

ARGUMENTS:
credkey:  The name used in creds.json (first parameter to NewDnsProvider() in dnsconfig.js)
provider: The name of the provider (second parameter to NewDnsProvider() in dnsconfig.js)
zone:     One or more zones (domains) to download; or "all".

FORMATS:
--format=js        dnsconfig.js format (not perfect, just a decent first draft)
--format=djs       js with disco commas (leading commas)
--format=zone      BIND zonefile format
--format=tsv       TAB separated value (useful for AWK)
--format=nameonly  Just print the zone names

The columns in --format=tsv are:

FQDN (the label with the domain)
ShortName (just the label, "@" if it is the naked domain)
TTL
Record Type (A, AAAA, CNAME, etc.)
Target and arguments (quoted like in a zonefile)

The --ttl flag only applies to zone/js/djs formats.

Examples

dnscontrol get-zones myr53 ROUTE53 example.com
dnscontrol get-zones gmain GANDI_V5 example.comn other.com
dnscontrol get-zones cfmain CLOUDFLAREAPI all
dnscontrol get-zones --format=tsv bind BIND example.com
dnscontrol get-zones --format=djs --out=draft.js glcoud GCLOUD example.com`,

Read a zonefile, generate a JS file, then use the JS file to see how different it is from the zonefile:

dnscontrol get-zone --format=djs -out=foo.djs bind BIND example.org
dnscontrol preview --config foo.js

Developer Notes

This command is not implemented for all providers.

To add this to a provider:

Step 1. Document the feature

In the *Provider.go file, change the setting to implemented.

Step 2. Update the docs

go generate

Step 3. Implement the GetZoneRecords function

Find the GetZoneRecords function in the *Provider.go file.

It currently returns fmt.Errorf("not implemented").

Instead, it should gather the records from the provider and return them as a list of RecordConfig structs.

The code to do that already exists in GetDomainCorrections. You should extract it into its own function (GetZoneRecords), rather than having it be buried in the middle of GetDomainCorrections. GetDomainCorrections should call GetZoneRecords.

Once that is done the get-zone subcommand should work.

Step 4. Optionally implement the ListZones function

If the ListZones function is implemented, the “all” special case will be activated. In this case, listing a single zone named all will query the provider for the list of zones.

(Technically what is happening is by implementing the ListZones function, you are completing the ZoneLister interface for that provider.)

Implementing the ListZones function also activates the check-creds subcommand for that provider. Please add to the provider documentation a list of error messages that people might see if the credentials are invalid. See docs/_providers/gcloud.md for examples.