coredns(plugin): Small fixes

* Update example Corefie and remove file directive
* Move the db-generator under plugin so the demo db can more easily be
  built and embedded in the coredns image.
* Add make target to generate demo db `make
  coredns-generate-demo-geo-db`.
* Fix imports and code formatting.

Signed-off-by: Michael Nairn <[email protected]>

Author: mikenairn

Makefile

@@ -155,6 +155,7 @@ lint: golangci-lint ## Run golangci-lint against code.
 .PHONY: imports
 imports: openshift-goimports ## Run openshift goimports against code.
 	$(OPENSHIFT_GOIMPORTS) -m github.com/kuadrant/dns-operator -i github.com/kuadrant
+	$(OPENSHIFT_GOIMPORTS) -p coredns/plugin -m github.com/kuadrant/coredns-kuadrant -i github.com/kuadrant
 
 .PHONY: test
 test: test-unit test-integration ## Run tests.

coredns/examples/Corefile

@@ -4,12 +4,7 @@ k.example.com {
    log
    geoip GeoLite2-City-demo.mmdb
    metadata
-   kuadrant {
-        kubeconfig /home/mnairn/.kube/config kind-kuadrant-dns-local-1
-   }
-}
-f.example.com {
-   file db.f.example.com
+   kuadrant
 }
 . {
    forward . /etc/resolv.conf

coredns/examples/db.f.example.com

@@ -1,5 +1,5 @@
 FROM alpine:3.21.0
 COPY coredns /
-COPY GeoLite2-City-demo.mmdb /
+COPY geoip/GeoLite2-City-demo.mmdb /
 EXPOSE 53 53/udp
 ENTRYPOINT ["/coredns"]

coredns/plugin/Dockerfile

@@ -1,6 +1,5 @@
 package main
 
-/*
 import (
 	"log"
 	"net"
@@ -110,4 +109,3 @@ func createCityDB(dbName, dbType string) {
 		log.Fatal(err)
 	}
 }
-*/

coredns/plugin/GeoLite2-City-demo.mmdb

@@ -0,0 +1,11 @@
+module geoip
+
+go 1.23.4
+
+require github.com/maxmind/mmdbwriter v1.0.0
+
+require (
+	github.com/oschwald/maxminddb-golang v1.13.1 // indirect
+	go4.org/netipx v0.0.0-20231129151722-fdeea329fbba // indirect
+	golang.org/x/sys v0.31.0 // indirect
+)

coredns/examples/GeoLite2-City-demo.mmdb coredns/plugin/geoip/GeoLite2-City-demo.mmdb

@@ -0,0 +1,22 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/maxmind/mmdbwriter v1.0.0 h1:bieL4P6yaYaHvbtLSwnKtEvScUKKD6jcKaLiTM3WSMw=
+github.com/maxmind/mmdbwriter v1.0.0/go.mod h1:noBMCUtyN5PUQ4H8ikkOvGSHhzhLok51fON2hcrpKj8=
+github.com/oschwald/maxminddb-golang v1.12.0 h1:9FnTOD0YOhP7DGxGsq4glzpGy5+w7pq50AS6wALUMYs=
+github.com/oschwald/maxminddb-golang v1.12.0/go.mod h1:q0Nob5lTCqyQ8WT6FYgS1L7PXKVVbgiymefNwIjPzgY=
+github.com/oschwald/maxminddb-golang v1.13.1 h1:G3wwjdN9JmIK2o/ermkHM+98oX5fS+k5MbwsmL4MRQE=
+github.com/oschwald/maxminddb-golang v1.13.1/go.mod h1:K4pgV9N/GcK694KSTmVSDTODk4IsCNThNdTmnaBZ/F8=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+go4.org/netipx v0.0.0-20220812043211-3cc044ffd68d h1:ggxwEf5eu0l8v+87VhX1czFh8zJul3hK16Gmruxn7hw=
+go4.org/netipx v0.0.0-20220812043211-3cc044ffd68d/go.mod h1:tgPU4N2u9RByaTN3NC2p9xOzyFpte4jYwsIIRF7XlSc=
+go4.org/netipx v0.0.0-20231129151722-fdeea329fbba h1:0b9z3AuHCjxk0x/opv64kcgZLBseWJUpBw5I82+2U4M=
+go4.org/netipx v0.0.0-20231129151722-fdeea329fbba/go.mod h1:PLyyIXexvUFg3Owu6p/WfdlivPbZJsZdgWZlrGope/Y=
+golang.org/x/sys v0.10.0 h1:SqMFp9UcQJZa+pmYuAKjd9xq1f0j5rLcDIk0mj4qAsA=
+golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.31.0 h1:ioabZlmFYtWhL+TRYpcnNlLwhyxaM9kWTDEmfnprqik=
+golang.org/x/sys v0.31.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

coredns/examples/db-generator.go coredns/plugin/geoip/db-generator.go

@@ -17,8 +17,9 @@ import (
 	"k8s.io/client-go/tools/cache"
 	"k8s.io/client-go/tools/clientcmd"
 
-	"github.com/kuadrant/coredns-kuadrant/dnsop"
 	"github.com/kuadrant/dns-operator/api/v1alpha1"
+
+	"github.com/kuadrant/coredns-kuadrant/dnsop"
 )
 
 const (

coredns/plugin/geoip/go.mod

@@ -6,14 +6,14 @@ import (
 	"strconv"
 	"strings"
 
-	"sigs.k8s.io/external-dns/endpoint"
-
 	"github.com/coredns/coredns/plugin/file"
 	"github.com/coredns/coredns/plugin/metadata"
 	"github.com/coredns/coredns/plugin/pkg/dnsutil"
 	"github.com/coredns/coredns/request"
 	"github.com/miekg/dns"
 
+	"sigs.k8s.io/external-dns/endpoint"
+
 	"github.com/kuadrant/dns-operator/api/v1alpha1"
 )
 
@@ -112,7 +112,7 @@ func (z *Zone) InsertEndpoint(ep *endpoint.Endpoint) error {
 		rrs = append(rrs, cname)
 	}
 
-	for i, _ := range rrs {
+	for i := range rrs {
 		rrd := rrData{}
 		if wProp, wExists := ep.GetProviderSpecificProperty(v1alpha1.ProviderSpecificWeight); wExists {
 			weight, err := strconv.ParseInt(wProp, 10, 64)

coredns/plugin/geoip/go.sum

@@ -22,7 +22,7 @@ coredns-run: ## Run coredns from your host.
 	cd ${COREDNS_PLUGIN_DIR} && go run --race ./cmd/coredns.go -dns.port ${DNS_PORT}
 
 .PHONY: coredns-docker-build
-coredns-docker-build: coredns-build ## Build docker image.
+coredns-docker-build: coredns-build coredns-generate-demo-geo-db ## Build docker image.
 	cd ${COREDNS_PLUGIN_DIR} && $(CONTAINER_TOOL) build . -t ${COREDNS_IMG}
 
 .PHONY: coredns-docker-push
@@ -33,3 +33,7 @@ coredns-docker-push: ## Push docker image.
 coredns-docker-run: DNS_PORT=1053
 coredns-docker-run: coredns-docker-build ## Build docker image and run coredns in a container.
 	cd ${COREDNS_PLUGIN_DIR} && $(CONTAINER_TOOL) run --rm -it -p ${DNS_PORT}:53/udp ${COREDNS_IMG}
+
+.PHONY: coredns-generate-demo-geo-db
+coredns-generate-demo-geo-db: ## Generate demo geo db embedded in coredns image.
+	cd ${COREDNS_PLUGIN_DIR}/geoip && go run db-generator.go