controller/bootstrap: use files with multiple yaml documents

Users can push manifests during bootstrap that of the form:

```yaml
---
```

Especially for the installer: setting authorizes_keys [1] and setting hyperthreading [2] will push a manifest that includes multiple machineconfig objects for
control-plane (master) and compute (worker) roles.

Single file with multiple k8s objects separated by `---` is also a supported structure for `oc create|apply` ie. there is a high chance that users trying to push machineconfigs at
install time might create such files.

This commit allows bootstrap controller to read all k8s objects, even ones described above to find all the `machineconfiguration.openshift.io` Objects.

[1]: openshift/installer#1150
[2]: openshift/installer#1392

pkg/controller/bootstrap/bootstrap.go

@@ -1,7 +1,10 @@
 package bootstrap
 
 import (
+	"bytes"
+	"errors"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -10,6 +13,7 @@ import (
 	"github.com/golang/glog"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	yamlutil "k8s.io/apimachinery/pkg/util/yaml"
 	kscheme "k8s.io/client-go/kubernetes/scheme"
 
 	"github.com/openshift/machine-config-operator/pkg/apis/machineconfiguration.openshift.io/v1"
@@ -63,28 +67,35 @@ func (b *Bootstrap) Run(destDir string) error {
 			continue
 		}
 
-		path := filepath.Join(b.manifestDir, info.Name())
-		raw, err := ioutil.ReadFile(path)
+		file, err := os.Open(filepath.Join(b.manifestDir, info.Name()))
 		if err != nil {
-			return err
+			return fmt.Errorf("error opening %s: %v", file.Name(), err)
 		}
+		defer file.Close()
 
-		obji, err := runtime.Decode(scheme.Codecs.UniversalDecoder(v1.SchemeGroupVersion), raw)
+		manifests, err := parseManifests(file.Name(), file)
 		if err != nil {
-			glog.V(4).Infof("skipping path because of error: %v", err)
-			// don't care
-			continue
+			return fmt.Errorf("error parsing manifests from %s: %v", file.Name(), err)
 		}
 
-		switch obj := obji.(type) {
-		case *v1.MachineConfigPool:
-			pools = append(pools, obj)
-		case *v1.MachineConfig:
-			configs = append(configs, obj)
-		case *v1.ControllerConfig:
-			cconfig = obj
-		default:
-			glog.Infof("skipping %q %T", path, obji)
+		for idx, m := range manifests {
+			obji, err := runtime.Decode(scheme.Codecs.UniversalDecoder(v1.SchemeGroupVersion), m.Raw)
+			if err != nil {
+				glog.V(4).Infof("skipping path %q [%d] manifest because of error: %v", file.Name(), idx+1, err)
+				// don't care
+				continue
+			}
+
+			switch obj := obji.(type) {
+			case *v1.MachineConfigPool:
+				pools = append(pools, obj)
+			case *v1.MachineConfig:
+				configs = append(configs, obj)
+			case *v1.ControllerConfig:
+				cconfig = obj
+			default:
+				glog.Infof("skipping %q [%d] manifest because %T", file.Name(), idx+1, obji)
+			}
 		}
 	}
 
@@ -148,3 +159,48 @@ func getPullSecretFromSecret(sData []byte) ([]byte, error) {
 	}
 	return s.Data[corev1.DockerConfigJsonKey], nil
 }
+
+type manifest struct {
+	Raw []byte
+}
+
+// UnmarshalJSON unmarshals bytes of single kubernetes object to manifest.
+func (m *manifest) UnmarshalJSON(in []byte) error {
+	if m == nil {
+		return errors.New("Manifest: UnmarshalJSON on nil pointer")
+	}
+
+	// This happens when marshalling
+	// <yaml>
+	// ---	(this between two `---`)
+	// ---
+	// <yaml>
+	if bytes.Equal(in, []byte("null")) {
+		m.Raw = nil
+		return nil
+	}
+
+	m.Raw = append(m.Raw[0:0], in...)
+	return nil
+}
+
+// parseManifests parses a YAML or JSON document that may contain one or more
+// kubernetes resources.
+func parseManifests(filename string, r io.Reader) ([]manifest, error) {
+	d := yamlutil.NewYAMLOrJSONDecoder(r, 1024)
+	var manifests []manifest
+	for {
+		m := manifest{}
+		if err := d.Decode(&m); err != nil {
+			if err == io.EOF {
+				return manifests, nil
+			}
+			return manifests, fmt.Errorf("error parsing %q: %v", filename, err)
+		}
+		m.Raw = bytes.TrimSpace(m.Raw)
+		if len(m.Raw) == 0 || bytes.Equal(m.Raw, []byte("null")) {
+			continue
+		}
+		manifests = append(manifests, m)
+	}
+}

pkg/controller/bootstrap/bootstrap_test.go

@@ -0,0 +1,119 @@
+package bootstrap
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+
+	"k8s.io/apimachinery/pkg/util/diff"
+)
+
+func TestParseManifests(t *testing.T) {
+	tests := []struct {
+		name string
+		raw  string
+		want []manifest
+	}{{
+		name: "ingress",
+		raw: `
+apiVersion: extensions/v1beta1
+kind: Ingress
+metadata:
+  name: test-ingress
+  namespace: test-namespace
+spec:
+  rules:
+  - http:
+      paths:
+      - path: /testpath
+        backend:
+          serviceName: test
+          servicePort: 80
+`,
+		want: []manifest{{
+			Raw: []byte(`{"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"name":"test-ingress","namespace":"test-namespace"},"spec":{"rules":[{"http":{"paths":[{"backend":{"serviceName":"test","servicePort":80},"path":"/testpath"}]}}]}}`),
+		}},
+	}, {
+		name: "two-resources",
+		raw: `
+apiVersion: extensions/v1beta1
+kind: Ingress
+metadata:
+  name: test-ingress
+  namespace: test-namespace
+spec:
+  rules:
+  - http:
+      paths:
+      - path: /testpath
+        backend:
+          serviceName: test
+          servicePort: 80
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: a-config
+  namespace: default
+data:
+  color: "red"
+  multi-line: |
+    hello world
+    how are you?
+`,
+		want: []manifest{{
+			Raw: []byte(`{"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"name":"test-ingress","namespace":"test-namespace"},"spec":{"rules":[{"http":{"paths":[{"backend":{"serviceName":"test","servicePort":80},"path":"/testpath"}]}}]}}`),
+		}, {
+			Raw: []byte(`{"apiVersion":"v1","data":{"color":"red","multi-line":"hello world\nhow are you?\n"},"kind":"ConfigMap","metadata":{"name":"a-config","namespace":"default"}}`),
+		}},
+	}, {
+		name: "two-resources-with-empty",
+		raw: `
+---
+apiVersion: extensions/v1beta1
+kind: Ingress
+metadata:
+  name: test-ingress
+  namespace: test-namespace
+spec:
+  rules:
+  - http:
+      paths:
+      - path: /testpath
+        backend:
+          serviceName: test
+          servicePort: 80
+---
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: a-config
+  namespace: default
+data:
+  color: "red"
+  multi-line: |
+    hello world
+    how are you?
+---
+`,
+		want: []manifest{{
+			Raw: []byte(`{"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"name":"test-ingress","namespace":"test-namespace"},"spec":{"rules":[{"http":{"paths":[{"backend":{"serviceName":"test","servicePort":80},"path":"/testpath"}]}}]}}`),
+		}, {
+			Raw: []byte(`{"apiVersion":"v1","data":{"color":"red","multi-line":"hello world\nhow are you?\n"},"kind":"ConfigMap","metadata":{"name":"a-config","namespace":"default"}}`),
+		}},
+	}}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			got, err := parseManifests("dummy-file-name", strings.NewReader(test.raw))
+			if err != nil {
+				t.Fatalf("failed to parse manifest: %v", err)
+			}
+
+			if !reflect.DeepEqual(got, test.want) {
+				t.Fatalf("mismatch found %s", diff.ObjectDiff(got, test.want))
+			}
+		})
+	}
+
+}