NEW FEATURE: IMPORT_TRANSFORM_STRIP (#3181)

documentation/SUMMARY.md

@@ -53,6 +53,7 @@
     * [IGNORE_NAME](language-reference/domain-modifiers/IGNORE_NAME.md)
     * [IGNORE_TARGET](language-reference/domain-modifiers/IGNORE_TARGET.md)
     * [IMPORT_TRANSFORM](language-reference/domain-modifiers/IMPORT_TRANSFORM.md)
+    * [IMPORT_TRANSFORM_STRIP](language-reference/domain-modifiers/IMPORT_TRANSFORM_STRIP.md)
     * [INCLUDE](language-reference/domain-modifiers/INCLUDE.md)
     * [LOC](language-reference/domain-modifiers/LOC.md)
     * [LOC_BUILDER_DD](language-reference/domain-modifiers/LOC_BUILDER_DD.md)

documentation/language-reference/domain-modifiers/IMPORT_TRANSFORM.md

@@ -3,6 +3,7 @@ name: IMPORT_TRANSFORM
 parameters:
   - transform table
   - domain
+  - ttl
   - modifiers...
 ts_ignore: true
 ---

documentation/language-reference/domain-modifiers/IMPORT_TRANSFORM_STRIP.md

@@ -0,0 +1,25 @@
+---
+name: IMPORT_TRANSFORM_STRIP
+parameters:
+  - transform table
+  - domain
+  - ttl
+  - suffixstrip
+  - modifiers...
+ts_ignore: true
+---
+
+{% hint style="warning" %}
+Don't use this feature. It was added for a very specific situation at Stack Overflow.
+{% endhint %}
+
+`IMPORT_TRANSFORM_STRIP` is the same as `IMPORT_TRANSFORM` with an additional parameter: `suffixstrip`.
+
+When `IMPORT_TRANSFORM_STRIP` is generating the label for new records, it
+checks the label.  If the label ends with `suffixstrip`, that suffix is removed.
+If the label does not end with `suffixstrip`, an error is returned.
+
+For example, if the domain is `com.extra` and the label is `foo.com`,
+`IMPORT_TRANSFORM` would generate a label `foo.com.com.extra`.
+`IMPORT_TRANSFORM_STRIP(... , '.com')` would generate
+the label `foo.com.extra` instead.

pkg/js/helpers.js

@@ -1031,7 +1031,7 @@ function IGNORE_TARGET(target, rType) {
     return IGNORE('*', rType, target);
 }
 
-// IMPORT_TRANSFORM(translation_table, domain)
+// IMPORT_TRANSFORM(translation_table, domain, ttl)
 var IMPORT_TRANSFORM = recordBuilder('IMPORT_TRANSFORM', {
     args: [['translation_table'], ['domain'], ['ttl', _.isNumber]],
     transform: function (record, args, modifiers) {
@@ -1042,6 +1042,18 @@ var IMPORT_TRANSFORM = recordBuilder('IMPORT_TRANSFORM', {
     },
 });
 
+// IMPORT_TRANSFORM_STRIP(translation_table, domain, ttl, suffixstrip)
+var IMPORT_TRANSFORM_STRIP = recordBuilder('IMPORT_TRANSFORM', {
+    args: [['translation_table'], ['domain'], ['ttl', _.isNumber], ['suffixstrip']],
+    transform: function (record, args, modifiers) {
+        record.name = '@';
+        record.target = args.domain;
+        record.meta['transform_table'] = format_tt(args.translation_table);
+        record.ttl = args.ttl;
+        record.meta['transform_suffixstrip'] = args.suffixstrip;
+    },
+});
+
 // PURGE()
 function PURGE(d) {
     d.KeepUnknown = false;

pkg/js/parse_tests/007-importTransformTTL.js

@@ -1,5 +1,25 @@
-var TRANSFORM_INT = [
-    {low: "0.0.0.0", high: "1.1.1.1", newBase: "2.2.2.2" }
-]
-D("foo2.com","reg");
-D("foo.com","reg",IMPORT_TRANSFORM(TRANSFORM_INT,"foo2.com",60))
+var TRANSFORM_NEWIP = [{
+    low: "0.0.0.0",
+    high: "1.1.1.1",
+    newIP: "2.2.2.2"
+}];
+var TRANSFORM_BASE = [{
+    low: "0.0.0.0",
+    high: "1.1.1.1",
+    newBase: "4.4.4.4"
+}, {
+    low: "7.7.7.7",
+    high: "8.8.8.8",
+    newBase: "9.9.9.9"
+},
+];
+
+D("foo1.com", "reg");
+
+D("foo2.com", "reg",
+    IMPORT_TRANSFORM(TRANSFORM_BASE, "foo1.com", 60)
+);
+
+D("foo3.com", "reg",
+    IMPORT_TRANSFORM_STRIP(TRANSFORM_NEWIP, "foo1.com", 99, ".com")
+);

pkg/js/parse_tests/007-importTransformTTL.json

@@ -1,28 +1,45 @@
 {
+  "registrars": [],
   "dns_providers": [],
   "domains": [
     {
+      "name": "foo1.com",
+      "registrar": "reg",
       "dnsProviders": {},
-      "name": "foo2.com",
-      "records": [],
-      "registrar": "reg"
+      "records": []
     },
     {
+      "name": "foo2.com",
+      "registrar": "reg",
       "dnsProviders": {},
-      "name": "foo.com",
       "records": [
         {
-          "meta": {
-            "transform_table": "0.0.0.0 ~ 1.1.1.1 ~ 2.2.2.2 ~ "
-          },
+          "type": "IMPORT_TRANSFORM",
           "name": "@",
-          "target": "foo2.com",
           "ttl": 60,
-          "type": "IMPORT_TRANSFORM"
+          "meta": {
+            "transform_table": "0.0.0.0 ~ 1.1.1.1 ~ 4.4.4.4 ~  ; 7.7.7.7 ~ 8.8.8.8 ~ 9.9.9.9 ~ "
+          },
+          "target": "foo1.com"
         }
-      ],
-      "registrar": "reg"
+      ]
+    },
+    {
+      "name": "foo3.com",
+      "registrar": "reg",
+      "dnsProviders": {},
+      "records": [
+        {
+          "type": "IMPORT_TRANSFORM",
+          "name": "@",
+          "ttl": 99,
+          "meta": {
+            "transform_suffixstrip": ".com",
+            "transform_table": "0.0.0.0 ~ 1.1.1.1 ~  ~ 2.2.2.2"
+          },
+          "target": "foo1.com"
+        }
+      ]
     }
-  ],
-  "registrars": []
-}
+  ]
+}

pkg/normalize/validate.go

@@ -119,7 +119,7 @@ func checkLabel(label string, rType string, domain string, meta map[string]strin
 	}
 	if label == domain || strings.HasSuffix(label, "."+domain) {
 		if m := meta["skip_fqdn_check"]; m != "true" {
-			return fmt.Errorf(errorRepeat(label, domain))
+			return fmt.Errorf("%s", errorRepeat(label, domain))
 		}
 	}
 
@@ -247,8 +247,27 @@ func transformCNAME(target, oldDomain, newDomain string) string {
 	return dnsutil.AddOrigin(result, newDomain) + "."
 }
 
+func newRec(rec *models.RecordConfig, ttl uint32) *models.RecordConfig {
+	rec2, _ := rec.Copy()
+	if ttl != 0 {
+		rec2.TTL = ttl
+	}
+	return rec2
+}
+
+func transformLabel(label, suffixstrip string) (string, error) {
+	if suffixstrip == "" {
+		return label, nil
+	}
+	if !strings.HasSuffix(label, suffixstrip) {
+		return "", fmt.Errorf("label %q does not end with %q", label, suffixstrip)
+	}
+	return label[:len(label)-len(suffixstrip)], nil
+}
+
 // import_transform imports the records of one zone into another, modifying records along the way.
-func importTransform(srcDomain, dstDomain *models.DomainConfig, transforms []transform.IPConversion, ttl uint32) error {
+func importTransform(srcDomain, dstDomain *models.DomainConfig,
+	transforms []transform.IPConversion, ttl uint32, suffixstrip string) error {
 	// Read srcDomain.Records, transform, and append to dstDomain.Records:
 	// 1. Skip any that aren't A or CNAMEs.
 	// 2. Append destDomainname to the end of the label.
@@ -259,15 +278,6 @@ func importTransform(srcDomain, dstDomain *models.DomainConfig, transforms []tra
 		if dstDomain.Records.HasRecordTypeName(rec.Type, rec.GetLabelFQDN()) {
 			continue
 		}
-		newRec := func() *models.RecordConfig {
-			rec2, _ := rec.Copy()
-			newlabel := rec2.GetLabelFQDN()
-			rec2.SetLabel(newlabel, dstDomain.Name)
-			if ttl != 0 {
-				rec2.TTL = ttl
-			}
-			return rec2
-		}
 		switch rec.Type {
 		case "A":
 			trs, err := transform.IPToList(net.ParseIP(rec.GetTargetField()), transforms)
@@ -275,12 +285,22 @@ func importTransform(srcDomain, dstDomain *models.DomainConfig, transforms []tra
 				return fmt.Errorf("import_transform: TransformIP(%v, %v) returned err=%s", rec.GetTargetField(), transforms, err)
 			}
 			for _, tr := range trs {
-				r := newRec()
+				r := newRec(rec, ttl)
+				l, err := transformLabel(r.GetLabelFQDN(), suffixstrip)
+				if err != nil {
+					return err
+				}
+				r.SetLabel(l, dstDomain.Name)
 				r.SetTarget(tr.String())
 				dstDomain.Records = append(dstDomain.Records, r)
 			}
 		case "CNAME":
-			r := newRec()
+			r := newRec(rec, ttl)
+			l, err := transformLabel(r.GetLabelFQDN(), suffixstrip)
+			if err != nil {
+				return err
+			}
+			r.SetLabel(l, dstDomain.Name)
 			r.SetTarget(transformCNAME(r.GetTargetField(), srcDomain.Name, dstDomain.Name))
 			dstDomain.Records = append(dstDomain.Records, r)
 		default:
@@ -445,6 +465,7 @@ func ValidateAndNormalizeConfig(config *models.DNSConfig) (errs []error) {
 	for _, domain := range config.Domains {
 		for _, rec := range domain.Records {
 			if rec.Type == "IMPORT_TRANSFORM" {
+				suffixstrip := rec.Metadata["transform_suffixstrip"]
 				table, err := transform.DecodeTransformTable(rec.Metadata["transform_table"])
 				if err != nil {
 					errs = append(errs, err)
@@ -455,7 +476,7 @@ func ValidateAndNormalizeConfig(config *models.DNSConfig) (errs []error) {
 					err = fmt.Errorf("IMPORT_TRANSFORM mentions non-existant domain %q", rec.GetTargetField())
 					errs = append(errs, err)
 				}
-				err = importTransform(c, domain, table, rec.TTL)
+				err = importTransform(c, domain, table, rec.TTL, suffixstrip)
 				if err != nil {
 					errs = append(errs, err)
 				}