Added a Docker image with bundled schemas

For cases where you don't want to hit the network the new offline images
contain the downloaded schemas.

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`

kubeval/kubeval.go

@@ -135,7 +135,7 @@ func validateResource(data []byte, fileName string) (ValidationResult, error) {
 
 	results, err := gojsonschema.Validate(schemaLoader, documentLoader)
 	if err != nil {
-		return result, fmt.Errorf("Problem loading schema from the network at %s", schema)
+		return result, fmt.Errorf("Problem loading schema from the network at %s: %s", schema, err)
 	}
 
 	if results.Valid() {