cluster/admitomatic: finish up service
This turns admitomatic into a self-standing service that can be used as
an admission controller.
I've tested this E2E on a local k3s server, and have some early test
code for that - but that'll land up in a follow up CR, as it first needs
to be cleaned up.
Change-Id: I46da0fc49f9d1a3a1a96700a36deb82e5057249b
diff --git a/cluster/admitomatic/BUILD.bazel b/cluster/admitomatic/BUILD.bazel
index 4d5aebc..55c7466 100644
--- a/cluster/admitomatic/BUILD.bazel
+++ b/cluster/admitomatic/BUILD.bazel
@@ -5,15 +5,18 @@
srcs = [
"ingress.go",
"main.go",
+ "service.go",
],
importpath = "code.hackerspace.pl/hscloud/cluster/admitomatic",
visibility = ["//visibility:private"],
deps = [
+ "//cluster/admitomatic/config:go_default_library",
"//go/mirko:go_default_library",
"@com_github_golang_glog//:go_default_library",
"@io_k8s_api//admission/v1beta1:go_default_library",
"@io_k8s_api//networking/v1beta1:go_default_library",
"@io_k8s_apimachinery//pkg/apis/meta/v1:go_default_library",
+ "@org_golang_google_protobuf//encoding/prototext:go_default_library",
],
)
diff --git a/cluster/admitomatic/config/BUILD.bazel b/cluster/admitomatic/config/BUILD.bazel
new file mode 100644
index 0000000..0344526
--- /dev/null
+++ b/cluster/admitomatic/config/BUILD.bazel
@@ -0,0 +1,23 @@
+load("@rules_proto//proto:defs.bzl", "proto_library")
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+load("@io_bazel_rules_go//proto:def.bzl", "go_proto_library")
+
+proto_library(
+ name = "config_proto",
+ srcs = ["config.proto"],
+ visibility = ["//visibility:public"],
+)
+
+go_proto_library(
+ name = "config_go_proto",
+ importpath = "code.hackerspace.pl/hscloud/cluster/admitomatic/config",
+ proto = ":config_proto",
+ visibility = ["//visibility:public"],
+)
+
+go_library(
+ name = "go_default_library",
+ embed = [":config_go_proto"],
+ importpath = "code.hackerspace.pl/hscloud/cluster/admitomatic/config",
+ visibility = ["//visibility:public"],
+)
diff --git a/cluster/admitomatic/config/config.proto b/cluster/admitomatic/config/config.proto
new file mode 100644
index 0000000..460c571
--- /dev/null
+++ b/cluster/admitomatic/config/config.proto
@@ -0,0 +1,37 @@
+syntax = "proto3";
+package config;
+option go_package = "code.hackerspace.pl/hscloud/cluster/admitomatic/config";
+
+// Admitomatic configuration, passed as a text proto, for
+// example:
+//
+// $ cat sample.pb.text
+// allow_domain { namespace: "example" dns: "*.example.com" }
+// allow_domain {
+// namespace: "personal-q3k" dns: "foo.q3k.org"
+// }
+// allow_domain {
+// namespace: "personal-q3k" dns: "bar.q3k.org"
+// }
+//
+message Config {
+ // List of domains that are allowed to be configured as
+ // ingresses in a given namespace. If a domain does not
+ // appear in this list, it will be allowed to run in any
+ // namespace.
+ repeated AllowDomain allow_domain = 1;
+}
+
+message AllowDomain {
+ // namespace is a kubernetes namespace. An empty string is
+ // treated as the 'default' namespace.
+ string namespace = 1;
+ // dns is a domain name like 'example.com' or a wildcard
+ // like '*.foo.example.com'.
+ // Wildcards match domains at any level beneath the root,
+ // so the example above would match 'bar.foo.example.com'
+ // and 'baz.bar.foo.example.com'. However, they do not
+ // catch the root itself, ie. the above would not catch
+ // 'foo.example.com'.
+ string dns = 2;
+}
diff --git a/cluster/admitomatic/config/sample.pb.text b/cluster/admitomatic/config/sample.pb.text
new file mode 100644
index 0000000..21e98bc
--- /dev/null
+++ b/cluster/admitomatic/config/sample.pb.text
@@ -0,0 +1,7 @@
+allow_domain { namespace: "example" dns: "*.example.com" }
+allow_domain {
+ namespace: "personal-q3k" dns: "foo.q3k.org"
+}
+allow_domain {
+ namespace: "personal-q3k" dns: "bar.q3k.org"
+}
diff --git a/cluster/admitomatic/ingress.go b/cluster/admitomatic/ingress.go
index 298318f..a1d57a5 100644
--- a/cluster/admitomatic/ingress.go
+++ b/cluster/admitomatic/ingress.go
@@ -6,7 +6,6 @@
"strings"
"github.com/golang/glog"
-
admission "k8s.io/api/admission/v1beta1"
networking "k8s.io/api/networking/v1beta1"
meta "k8s.io/apimachinery/pkg/apis/meta/v1"
diff --git a/cluster/admitomatic/main.go b/cluster/admitomatic/main.go
index 3178818..b05ff2f 100644
--- a/cluster/admitomatic/main.go
+++ b/cluster/admitomatic/main.go
@@ -3,6 +3,7 @@
import (
"context"
"flag"
+ "io/ioutil"
"net/http"
"time"
@@ -11,13 +12,29 @@
)
var (
- flagListen = "127.0.0.1:8080"
+ flagListen = "127.0.0.1:8080"
+ flagConfig = ""
+ flagTLSKey = ""
+ flagTLSCert = ""
)
func main() {
- flag.StringVar(&flagListen, "pub_listen", flagListen, "Address to listen on for HTTP traffic")
+ flag.StringVar(&flagListen, "admitomatic_listen", flagListen, "Address to listen on for HTTP traffic")
+ flag.StringVar(&flagTLSKey, "admitomatic_tls_key", flagTLSKey, "TLS key to serve HTTP with")
+ flag.StringVar(&flagTLSCert, "admitomatic_tls_cert", flagTLSCert, "TLS certificate to serve HTTP with")
+ flag.StringVar(&flagConfig, "admitomatic_config", flagConfig, "Config path (prototext format)")
flag.Parse()
+ if flagConfig == "" {
+ glog.Exitf("-admitomatic_config must be set")
+ }
+ if flagTLSKey == "" {
+ glog.Exitf("-admitomatic_tls_key must be set")
+ }
+ if flagTLSCert == "" {
+ glog.Exitf("-admitomatic_tls_cert must be set")
+ }
+
m := mirko.New()
if err := m.Listen(); err != nil {
glog.Exitf("Listen(): %v", err)
@@ -27,13 +44,24 @@
glog.Exitf("Serve(): %v", err)
}
+ configData, err := ioutil.ReadFile(flagConfig)
+ if err != nil {
+ glog.Exitf("Could not read config: %v", err)
+ }
+
+ s, err := newService(configData)
+ if err != nil {
+ glog.Exitf("Could not start service: %v", err)
+ }
+
mux := http.NewServeMux()
+ mux.HandleFunc("/", s.handler)
// TODO(q3k): implement admission controller
srv := &http.Server{Addr: flagListen, Handler: mux}
glog.Infof("Listening on %q...", flagListen)
go func() {
- if err := srv.ListenAndServe(); err != nil {
+ if err := srv.ListenAndServeTLS(flagTLSCert, flagTLSKey); err != nil {
glog.Error(err)
}
}()
diff --git a/cluster/admitomatic/service.go b/cluster/admitomatic/service.go
new file mode 100644
index 0000000..8fa2698
--- /dev/null
+++ b/cluster/admitomatic/service.go
@@ -0,0 +1,105 @@
+package main
+
+import (
+ "encoding/json"
+ "fmt"
+ "io/ioutil"
+ "net/http"
+
+ "github.com/golang/glog"
+ "google.golang.org/protobuf/encoding/prototext"
+ admission "k8s.io/api/admission/v1beta1"
+ meta "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+ pb "code.hackerspace.pl/hscloud/cluster/admitomatic/config"
+)
+
+type service struct {
+ ingress ingressFilter
+}
+
+// newService creates an admitomatic service from a given prototext config.
+func newService(configuration []byte) (*service, error) {
+ var cfg pb.Config
+ if err := prototext.Unmarshal(configuration, &cfg); err != nil {
+ return nil, fmt.Errorf("parsing config: %v", err)
+ }
+
+ s := service{}
+
+ for i, ad := range cfg.AllowDomain {
+ if ad.Namespace == "" {
+ ad.Namespace = "default"
+ }
+ if ad.Dns == "" {
+ return nil, fmt.Errorf("config entry %d: dns must be set", i)
+ }
+ if err := s.ingress.allow(ad.Namespace, ad.Dns); err != nil {
+ return nil, fmt.Errorf("config entry %d: %v", i, err)
+ }
+ glog.Infof("Ingress: allowing %s in %s", ad.Dns, ad.Namespace)
+ }
+ return &s, nil
+}
+
+// handler is the main HTTP handler of the admitomatic service. It servers the
+// AdmissionReview API, and is called by the Kubernetes API server to
+// permit/deny creation/updating of resources.
+func (s *service) handler(w http.ResponseWriter, r *http.Request) {
+ var body []byte
+ if r.Body != nil {
+ if data, err := ioutil.ReadAll(r.Body); err == nil {
+ body = data
+ }
+ }
+
+ if r.Method != "POST" {
+ glog.Errorf("%s %s: invalid method", r.Method, r.URL)
+ return
+ }
+
+ contentType := r.Header.Get("Content-Type")
+ if contentType != "application/json" {
+ glog.Errorf("%s %s: invalid content-type", r.Method, r.URL)
+ return
+ }
+
+ var review admission.AdmissionReview
+ if err := json.Unmarshal(body, &review); err != nil {
+ glog.Errorf("%s %s: cannot decode: %v", r.Method, r.URL, err)
+ return
+ }
+
+ if review.Kind != "AdmissionReview" {
+ glog.Errorf("%s %s: invalid Kind (%q)", r.Method, r.URL, review.Kind)
+ return
+ }
+
+ var err error
+ req := review.Request
+ resp := &admission.AdmissionResponse{
+ UID: req.UID,
+ Allowed: true,
+ }
+ switch {
+ case req.Kind.Group == "networking.k8s.io" && req.Kind.Kind == "Ingress":
+ resp, err = s.ingress.admit(req)
+ if err != nil {
+ glog.Errorf("%s %s %s: %v", req.Operation, req.Name, req.Namespace, err)
+ // Fail safe.
+ // TODO(q3k): monitor this?
+ resp = &admission.AdmissionResponse{
+ UID: req.UID,
+ Allowed: false,
+ Result: &meta.Status{
+ Code: 500,
+ Message: "admitomatic: internal server error",
+ },
+ }
+ }
+ }
+
+ glog.Infof("%s %s %s in %s: %v (%v)", req.Operation, req.Kind.Kind, req.Name, req.Namespace, resp.Allowed, resp.Result)
+ review.Response = resp
+ json.NewEncoder(w).Encode(review)
+}