Merge pull request #28 from garethr/schema-location-support

Schema location support

Dockerfile.offline

@@ -0,0 +1,20 @@
+FROM golang:1.8-alpine as builder
+RUN apk --no-cache add make git
+RUN mkdir -p /go/src/github.com/garethr/kubeval/
+COPY . /go/src/github.com/garethr/kubeval/
+WORKDIR /go/src/github.com/garethr/kubeval/
+RUN make linux
+
+FROM alpine:latest as schemas
+RUN apk --no-cache add git
+RUN git clone https://github.com/garethr/kubernetes-json-schema.git
+RUN git clone https://github.com/garethr/openshift-json-schema.git
+
+FROM alpine:latest
+RUN apk --no-cache add ca-certificates
+COPY --from=builder /go/src/github.com/garethr/kubeval/bin/linux/amd64/kubeval .
+COPY --from=schemas /kubernetes-json-schema /schemas/kubernetes-json-schema/master
+COPY --from=schemas /openshift-json-schema /schemas/openshift-json-schema/master
+ENV KUBEVAL_SCHEMA_LOCATION=file:///schemas
+ENTRYPOINT ["/kubeval"]
+CMD ["--help"]

Makefile

@@ -74,9 +74,15 @@ docker:
 	docker build -t garethr/kubeval:$(TAG) .
 	docker tag garethr/kubeval:$(TAG) garethr/kubeval:latest
 
-publish: docker
+docker-offline:
+	docker build -f Dockerfile.offline -t garethr/kubeval:$(TAG)-offline .
+	docker tag garethr/kubeval:$(TAG)-offline garethr/kubeval:offline
+
+publish: docker docker-offline
 	docker push garethr/kubeval:$(TAG)
 	docker push garethr/kubeval:latest
+	docker push garethr/kubeval:$(TAG)-offline
+	docker push garethr/kubeval:offline
 
 vet:
 	go vet `glide novendor`

README.md

@@ -118,9 +118,13 @@ Validate a Kubernetes YAML file against the relevant schema
 Usage:
   kubeval <file> [file...] [flags]
 
-Flags:
-  -v, --kubernetes-version string   Version of Kubernetes to validate against (default "master")
-      --openshift                   Use OpenShift schemas instead of upstream Kubernetes
+  Flags:
+    -h, --help                        help for kubeval
+    -v, --kubernetes-version string   Version of Kubernetes to validate against (default "master")
+        --openshift                   Use OpenShift schemas instead of upstream Kubernetes
+        --schema-location string      Base URL used to download schemas. Can also be specified with the environment variable KUBEVAL_SCHEMA_LOCATION (default "https://raw.githubusercontent.com/garethr")
+        --version                     Display the kubeval version information and exit
+
 ```
 
 The command has three important features:

cmd/root.go

@@ -9,6 +9,7 @@ import (
 	"runtime"
 
 	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
 
 	"github.com/garethr/kubeval/kubeval"
 	"github.com/garethr/kubeval/log"
@@ -102,7 +103,11 @@ func Execute() {
 }
 
 func init() {
+	viper.SetEnvPrefix("KUBEVAL")
+	viper.AutomaticEnv()
 	RootCmd.Flags().StringVarP(&kubeval.Version, "kubernetes-version", "v", "master", "Version of Kubernetes to validate against")
+	RootCmd.Flags().StringVarP(&kubeval.SchemaLocation, "schema-location", "", kubeval.DefaultSchemaLocation, "Base URL used to download schemas. Can also be specified with the environment variable KUBEVAL_SCHEMA_LOCATION")
 	RootCmd.Flags().BoolVarP(&kubeval.OpenShift, "openshift", "", false, "Use OpenShift schemas instead of upstream Kubernetes")
 	RootCmd.Flags().BoolVarP(&Version, "version", "", false, "Display the kubeval version information and exit")
+	viper.BindPFlag("schema_location", RootCmd.Flags().Lookup("schema-location"))
 }

glide.yaml

@@ -6,3 +6,5 @@ import:
 - package: github.com/fatih/color
   version: ^1.5.0
 - package: github.com/hashicorp/go-multierror
+- package: github.com/spf13/viper
+  version: ^1.0.0

kubeval/kubeval.go

@@ -4,9 +4,10 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	"strings"
 	"runtime"
+	"strings"
 
+	"github.com/spf13/viper"
 	"github.com/hashicorp/go-multierror"
 	"github.com/xeipuuv/gojsonschema"
 	"gopkg.in/yaml.v2"
@@ -16,6 +17,14 @@ import (
 // for which we should load the schema
 var Version string
 
+// SchemaLocation represents what is the schema location,
+/// where default value is maintener github project, but can be overriden
+/// to either different github repo, or a local file
+var SchemaLocation string
+
+// DefaultSchemaLocation is the default value for
+var DefaultSchemaLocation = "https://raw.githubusercontent.com/garethr"
+
 // OpenShift represents whether to test against
 // upstream Kubernetes of the OpenShift schemas
 var OpenShift bool
@@ -69,7 +78,20 @@ func determineSchema(kind string) string {
 		normalisedVersion = "v" + normalisedVersion
 	}
 
-	return fmt.Sprintf("https://raw.githubusercontent.com/garethr/%s-json-schema/master/%s-standalone/%s.json", schemaType, normalisedVersion, strings.ToLower(kind))
+	// Check Viper for environment variable support first.
+	// Then check for an override in SchemaLocation
+	// Finally settle on the default value
+	baseURLFromEnv := viper.GetString("schema_location")
+	var baseURL string
+	if baseURLFromEnv != "" {
+		baseURL = baseURLFromEnv
+	} else if SchemaLocation == "" {
+		baseURL = DefaultSchemaLocation
+	} else {
+		baseURL = SchemaLocation
+	}
+
+	return fmt.Sprintf("%s/%s-json-schema/master/%s-standalone/%s.json", baseURL, schemaType, normalisedVersion, strings.ToLower(kind))
 }
 
 func determineKind(body interface{}) (string, error) {
@@ -113,7 +135,7 @@ func validateResource(data []byte, fileName string) (ValidationResult, error) {
 
 	results, err := gojsonschema.Validate(schemaLoader, documentLoader)
 	if err != nil {
-		return result, errors.New("Problem loading schema from the network")
+		return result, fmt.Errorf("Problem loading schema from the network at %s: %s", schema, err)
 	}
 
 	if results.Valid() {
@@ -132,7 +154,7 @@ func Validate(config []byte, fileName string) ([]ValidationResult, error) {
 		return nil, errors.New("The document " + fileName + " appears to be empty")
 	}
 
-	bits := bytes.Split(config, []byte("---" + detectLineBreak(config)))
+	bits := bytes.Split(config, []byte("---"+detectLineBreak(config)))
 
 	results := make([]ValidationResult, 0)
 	var errors *multierror.Error

kubeval/kubeval_test.go

@@ -86,6 +86,15 @@ func TestDetermineSchemaForVersions(t *testing.T) {
 	}
 }
 
+func TestDetermineSchemaForSchemaLocation(t *testing.T) {
+	SchemaLocation = "file:///home/me"
+	schema := determineSchema("sample")
+	expectedSchema := "file:///home/me/openshift-json-schema/master/v1.0-standalone/sample.json"
+	if schema != expectedSchema {
+		t.Errorf("Should be able to specify a schema location, expected %s, got %s instead ", expectedSchema, schema)
+	}
+}
+
 func TestDetermineKind(t *testing.T) {
 	_, err := determineKind("sample")
 	if err == nil {