NEW FEATURE: NO_PURGE reports what is not purged (diff2 only) (#2031)

pkg/diff/diff2compat.go

@@ -1,6 +1,8 @@
 package diff
 
 import (
+	"fmt"
+
 	"github.com/StackExchange/dnscontrol/v3/models"
 	"github.com/StackExchange/dnscontrol/v3/pkg/diff2"
 )
@@ -62,6 +64,9 @@ func (d *differCompat) IncrementalDiff(existing []*models.RecordConfig) (unchang
 	for _, inst := range instructions {
 		cor := Correlation{d: d.OldDiffer}
 		switch inst.Type {
+		case diff2.REPORT:
+			// Sadly the NewCompat function doesn't have a way to do this.
+			// Purge reports are silently skipped.
 		case diff2.CREATE:
 			cor.Desired = inst.New[0]
 			create = append(create, cor)
@@ -72,6 +77,8 @@ func (d *differCompat) IncrementalDiff(existing []*models.RecordConfig) (unchang
 		case diff2.DELETE:
 			cor.Existing = inst.Old[0]
 			toDelete = append(toDelete, cor)
+		default:
+			panic(fmt.Sprintf("unhandled inst.Type %s", inst.Type))
 		}
 	}
 

pkg/diff2/diff2.go

@@ -19,6 +19,7 @@ const (
 	CREATE             // Create a record/recordset/label where none existed before.
 	CHANGE             // Change existing record/recordset/label
 	DELETE             // Delete existing record/recordset/label
+	REPORT             // No change, but boy do I have something to say!
 )
 
 type ChangeList []Change
@@ -48,28 +49,33 @@ General instructions:
 
   for _, change := range changes {
     switch change.Type {
+    case diff2.REPORT:
+      corr = &models.Correction{Msg: change.MsgsJoined}
     case diff2.CREATE:
       corr = &models.Correction{
         Msg: change.MsgsJoined,
         F: func() error {
-          return c.createRecord(FILL IN)
+          return c.createRecord(FILL_IN)
         },
       }
     case diff2.CHANGE:
       corr = &models.Correction{
         Msg: change.MsgsJoined,
         F: func() error {
-          return c.modifyRecord(FILL IN)
+          return c.modifyRecord(FILL_IN)
         },
       }
     case diff2.DELETE:
       corr = &models.Correction{
         Msg: change.MsgsJoined,
         F: func() error {
-          return c.deleteRecord(FILL IN)
+          return c.deleteRecord(FILL_IN)
         },
       }
+	  default:
+		  panic("unhandled change.TYPE %s", change.Type)
     }
+
     corrections = append(corrections, corr)
   }
 

pkg/diff2/nopurge.go

@@ -1,5 +1,7 @@
 package diff2
 
+import "strings"
+
 func processPurge(instructions ChangeList, nopurge bool) ChangeList {
 
 	if nopurge {
@@ -9,14 +11,30 @@ func processPurge(instructions ChangeList, nopurge bool) ChangeList {
 	// TODO(tlim): This can probably be done without allocations but it
 	// works and I won't want to prematurely optimize.
 
+	var msgs []string
+
 	newinstructions := make(ChangeList, 0, len(instructions))
 	for _, j := range instructions {
 		if j.Type == DELETE {
+			msgs = append(msgs, j.Msgs...)
 			continue
 		}
 		newinstructions = append(newinstructions, j)
 	}
 
+	// Report what would have been purged
+	if len(msgs) != 0 {
+		for i := range msgs {
+			msgs[i] = "NO_PURGE: Skipping " + msgs[i]
+		}
+		msgs = append([]string{"NO_PURGE Activated! Skipping these actions:"}, msgs...)
+		newinstructions = append(newinstructions, Change{
+			Type:       REPORT,
+			Msgs:       msgs,
+			MsgsJoined: strings.Join(msgs, "\n"),
+		})
+	}
+
 	return newinstructions
 
 }

providers/azuredns/azureDnsProvider.go

@@ -340,6 +340,9 @@ func (a *azurednsProvider) GetDomainCorrections(dc *models.DomainConfig) ([]*mod
 	for _, inst := range instructions {
 		switch inst.Type {
 
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: inst.MsgsJoined})
+
 		case diff2.CHANGE, diff2.CREATE:
 			var rrset *adns.RecordSet
 			var recordName string
@@ -390,6 +393,10 @@ func (a *azurednsProvider) GetDomainCorrections(dc *models.DomainConfig) ([]*mod
 						return nil
 					},
 				})
+
+		default:
+			panic(fmt.Sprintf("unhandled inst.Type %s", inst.Type))
+
 		}
 
 	}

providers/gandiv5/gandi_v5Provider.go

@@ -361,6 +361,9 @@ func (client *gandiv5Provider) GenerateDomainCorrections(dc *models.DomainConfig
 	for _, inst := range instructions {
 		switch inst.Type {
 
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: inst.MsgsJoined})
+
 		case diff2.CREATE:
 			// We have to create the label one rtype at a time.
 			natives := recordsToNative(inst.New, dc.Name)
@@ -420,6 +423,9 @@ func (client *gandiv5Provider) GenerateDomainCorrections(dc *models.DomainConfig
 						return nil
 					},
 				})
+
+		default:
+			panic(fmt.Sprintf("unhandled inst.Type %s", inst.Type))
 		}
 
 	}

providers/gcore/gcoreProvider.go

@@ -158,6 +158,7 @@ func (c *gcoreProvider) GenerateDomainCorrections(dc *models.DomainConfig, exist
 	// Make delete happen earlier than creates & updates.
 	var corrections []*models.Correction
 	var deletions []*models.Correction
+	var reports []*models.Correction
 
 	if !diff2.EnableDiff2 {
 
@@ -246,6 +247,8 @@ func (c *gcoreProvider) GenerateDomainCorrections(dc *models.DomainConfig, exist
 			msg := generateChangeMsg(change.Msgs)
 
 			switch change.Type {
+			case diff2.REPORT:
+				corrections = append(corrections, &models.Correction{Msg: change.MsgsJoined})
 			case diff2.CREATE:
 				corrections = append(corrections, &models.Correction{
 					Msg: msg,
@@ -267,9 +270,13 @@ func (c *gcoreProvider) GenerateDomainCorrections(dc *models.DomainConfig, exist
 						return c.provider.DeleteRRSet(c.ctx, zone, name, typ)
 					},
 				})
+			default:
+				panic(fmt.Sprintf("unhandled change.Type %s", change.Type))
 			}
 		}
 	}
 
-	return append(deletions, corrections...), nil
+	result := append(reports, deletions...)
+	result = append(result, corrections...)
+	return result, nil
 }

providers/hedns/hednsProvider.go

@@ -259,6 +259,8 @@ func (c *hednsProvider) getDiff2DomainCorrections(dc *models.DomainConfig, zoneI
 	var corrections []*models.Correction
 	for _, change := range changes {
 		switch change.Type {
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: change.MsgsJoined})
 		case diff2.CREATE:
 			record := change.New[0]
 			corrections = append(corrections, &models.Correction{
@@ -284,6 +286,8 @@ func (c *hednsProvider) getDiff2DomainCorrections(dc *models.DomainConfig, zoneI
 					return c.deleteZoneRecord(zoneID, recordID)
 				},
 			})
+		default:
+			panic(fmt.Sprintf("unhandled change.Type %s", change.Type))
 		}
 	}
 

providers/ns1/ns1Provider.go

@@ -212,25 +212,28 @@ func (n *nsone) GetDomainCorrections(dc *models.DomainConfig) ([]*models.Correct
 		recs := change.New
 		desc := strings.Join(change.Msgs, "\n")
 
-		if change.Type == diff2.CREATE {
+		switch change.Type {
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: change.MsgsJoined})
+		case diff2.CREATE:
 			corrections = append(corrections, &models.Correction{
 				Msg: desc,
 				F:   func() error { return n.add(recs, dc.Name) },
 			})
-		}
+		case diff2.CHANGE:
-		if change.Type == diff2.CHANGE {
 			corrections = append(corrections, &models.Correction{
 				Msg: desc,
 				F:   func() error { return n.modify(recs, dc.Name) },
 			})
-
+		case diff2.DELETE:
-		}
-		if change.Type == diff2.DELETE {
 			corrections = append(corrections, &models.Correction{
 				Msg: desc,
 				F:   func() error { return n.remove(key, dc.Name) },
 			})
+		default:
+			panic(fmt.Sprintf("unhandled inst.Type %s", change.Type))
 		}
+
 	}
 	return corrections, nil
 }

providers/ovh/ovhProvider.go

@@ -201,6 +201,8 @@ func (c *ovhProvider) getDiff2DomainCorrections(dc *models.DomainConfig, actual
 
 	for _, inst := range instructions {
 		switch inst.Type {
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: inst.MsgsJoined})
 		case diff2.CHANGE:
 			corrections = append(corrections, &models.Correction{
 				Msg: inst.Msgs[0],
@@ -217,6 +219,8 @@ func (c *ovhProvider) getDiff2DomainCorrections(dc *models.DomainConfig, actual
 				Msg: inst.Msgs[0],
 				F:   c.deleteRecordFunc(rec.ID, dc.Name),
 			})
+		default:
+			panic(fmt.Sprintf("unhandled inst.Type %s", inst.Type))
 		}
 	}
 	return corrections, nil

providers/porkbun/porkbunProvider.go

@@ -161,6 +161,8 @@ func (c *porkbunProvider) GetDomainCorrections(dc *models.DomainConfig) ([]*mode
 	for _, change := range changes {
 		var corr *models.Correction
 		switch change.Type {
+		case diff2.REPORT:
+			corr = &models.Correction{Msg: change.MsgsJoined}
 		case diff2.CREATE:
 			req, err := toReq(change.New[0])
 			if err != nil {
@@ -192,6 +194,8 @@ func (c *porkbunProvider) GetDomainCorrections(dc *models.DomainConfig) ([]*mode
 					return c.deleteRecord(dc.Name, id)
 				},
 			}
+		default:
+			panic(fmt.Sprintf("unhandled change.Type %s", change.Type))
 		}
 		corrections = append(corrections, corr)
 	}

providers/route53/route53Provider.go

@@ -488,6 +488,9 @@ func (r *route53Provider) GetDomainCorrections(dc *models.DomainConfig) ([]*mode
 
 		switch inst.Type {
 
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: inst.MsgsJoined})
+
 		case diff2.CREATE:
 			fallthrough
 		case diff2.CHANGE:
@@ -529,6 +532,10 @@ func (r *route53Provider) GetDomainCorrections(dc *models.DomainConfig) ([]*mode
 				Action:            r53Types.ChangeActionDelete,
 				ResourceRecordSet: &rrset,
 			}
+
+		default:
+			panic(fmt.Sprintf("unhandled inst.Type %s", inst.Type))
+
 		}
 
 		changes = append(changes, chg)

providers/vultr/vultrProvider.go

@@ -183,6 +183,8 @@ func (api *vultrProvider) GetDomainCorrections(dc *models.DomainConfig) ([]*mode
 
 	for _, change := range changes {
 		switch change.Type {
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: change.MsgsJoined})
 		case diff2.CREATE:
 			r := toVultrRecord(dc, change.New[0], "0")
 			corrections = append(corrections, &models.Correction{
@@ -208,6 +210,8 @@ func (api *vultrProvider) GetDomainCorrections(dc *models.DomainConfig) ([]*mode
 					return api.client.DomainRecord.Delete(context.Background(), dc.Name, id)
 				},
 			})
+		default:
+			panic(fmt.Sprintf("unhandled change.Type %s", change.Type))
 		}
 	}