Added support for DNS zone files (#1961)

This adds support for DNS zone files.

The highlighting is quite simple as every type and class is highlighted as `keyword`. This is intentional as other token names (e.g. `class-name`, `function`, `builtin`, ...) are not highlighted by every theme resulting in large portions of unstyled text for some themes.

Author: RunDevelopment

components.js

@@ -240,6 +240,11 @@
 			"alias": "jinja2",
 			"owner": "romanvm"
 		},
+		"dns-zone-file": {
+			"title": "DNS zone file",
+			"owner": "RunDevelopment",
+			"alias": "dns-zone"
+		},
 		"docker": {
 			"title": "Docker",
 			"alias": "dockerfile",

components.json

@@ -0,0 +1,33 @@
+Prism.languages['dns-zone-file'] = {
+	'comment': /;.*/,
+	'string': {
+		pattern: /"(?:\\.|[^"\\\r\n])*"/,
+		greedy: true
+	},
+	'variable': [
+		{
+			pattern: /(^\$ORIGIN[ \t]+)\S+/m,
+			lookbehind: true,
+		},
+		{
+			pattern: /(^|\s)@(?=\s|$)/,
+			lookbehind: true,
+		}
+	],
+	'keyword': /^\$(?:ORIGIN|INCLUDE|TTL)(?=\s|$)/m,
+	'class': {
+		// https://tools.ietf.org/html/rfc1035#page-13
+		pattern: /(^|\s)(?:IN|CH|CS|HS)(?=\s|$)/,
+		lookbehind: true,
+		alias: 'keyword'
+	},
+	'type': {
+		// https://en.wikipedia.org/wiki/List_of_DNS_record_types
+		pattern: /(^|\s)(?:A|A6|AAAA|AFSDB|APL|ATMA|CAA|CDNSKEY|CDS|CERT|CNAME|DHCID|DLV|DNAME|DNSKEY|DS|EID|GID|GPOS|HINFO|HIP|IPSECKEY|ISDN|KEY|KX|LOC|MAILA|MAILB|MB|MD|MF|MG|MINFO|MR|MX|NAPTR|NB|NBSTAT|NIMLOC|NINFO|NS|NSAP|NSAP-PTR|NSEC|NSEC3|NSEC3PARAM|NULL|NXT|OPENPGPKEY|PTR|PX|RKEY|RP|RRSIG|RT|SIG|SINK|SMIMEA|SOA|SPF|SRV|SSHFP|TA|TKEY|TLSA|TSIG|TXT|UID|UINFO|UNSPEC|URI|WKS|X25)(?=\s|$)/,
+		lookbehind: true,
+		alias: 'keyword'
+	},
+	'punctuation': /[()]/
+};
+
+Prism.languages['dns-zone'] = Prism.languages['dns-zone-file']

components/prism-dns-zone-file.js

@@ -0,0 +1,14 @@
+<h2>Full example</h2>
+<pre><code>$TTL 3d
+@ IN SOA root.localhost. root.sneaky.net. (
+    2015050503 ; serial
+    12h        ; refresh
+    15m        ; retry
+    3w         ; expire
+    3h         ; negative response TTL
+  )
+  IN NS root.localhost.
+  IN NS localhost. ; secondary name server is preferably externally maintained
+
+www IN A 3.141.59.26
+ww1 IN CNAME www</code></pre>

components/prism-dns-zone-file.min.js

@@ -133,6 +133,7 @@
 		"dotnet": "csharp",
 		"coffee": "coffeescript",
 		"jinja2": "django",
+		"dns-zone": "dns-zone-file",
 		"dockerfile": "docker",
 		"gamemakerlanguage": "gml",
 		"hs": "haskell",

examples/prism-dns-zone-file.html

@@ -45,6 +45,8 @@
 		"css-extras": "CSS Extras",
 		"django": "Django/Jinja2",
 		"jinja2": "Django/Jinja2",
+		"dns-zone-file": "DNS zone file",
+		"dns-zone": "DNS zone file",
 		"dockerfile": "Docker",
 		"ebnf": "Extended Backus–Naur form",
 		"ejs": "EJS",

plugins/autoloader/prism-autoloader.js

@@ -0,0 +1,17 @@
+IN
+CH
+CS
+HS
+
+----------------------------------------------------
+
+[
+	["class", "IN"],
+	["class", "CH"],
+	["class", "CS"],
+	["class", "HS"]
+]
+
+----------------------------------------------------
+
+Checks for all resource record classes.