From 07883b8bb44904a95843189d3f9d53b348220093 Mon Sep 17 00:00:00 2001
From: Yann Hamon <yann.hamon@contentful.com>
Date: Sat, 17 Oct 2020 17:21:33 +0200
Subject: [PATCH] Update Readme, converter helper script can now reads straight
 from http

---
 Readme.md                      | 10 ++++++++++
 cmd/openapi2jsonschema/main.py |  7 ++++++-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/Readme.md b/Readme.md
index 4602fde..3d24d87 100644
--- a/Readme.md
+++ b/Readme.md
@@ -118,6 +118,16 @@ in a local folder - for example schemas. Then we specify this folder as an addit
 $ ./bin/kubeconform -registry kubernetesjsonschema.dev -registry 'schemas/{{ .ResourceKind }}{{ .KindSuffix }}.json' fixtures/custom-resource.yaml
 ```
 
+### Generating a JSON schema from an OpenAPI file
+
+Kubeconform uses JSON schemas to validate Kubernetes resources. For Custom Resource, the CustomResourceDefinition
+first needs to be converted to JSON Schema. A script is provided to convert these CustomResourceDefinitions 
+to JSON schema. Here is an example how to use it:
+
+```
+$ ./cmd/openapi2jsonschema/main.py https://raw.githubusercontent.com/aws/amazon-sagemaker-operator-for-k8s/master/config/crd/bases/sagemaker.aws.amazon.com_trainingjobs.yaml > fixtures/registry/trainingjob-sagemaker-v1.json
+```
+
 ### Credits
 
  * @garethr for the [Kubeval](https://github.com/instrumenta/kubeval) and
diff --git a/cmd/openapi2jsonschema/main.py b/cmd/openapi2jsonschema/main.py
index 95f7ebb..77eb3ee 100755
--- a/cmd/openapi2jsonschema/main.py
+++ b/cmd/openapi2jsonschema/main.py
@@ -4,6 +4,7 @@
 import yaml
 import json
 import sys
+import urllib.request
 
 def iteritems(d):
     if hasattr(dict, "iteritems"):
@@ -90,7 +91,11 @@ if len(sys.argv) == 0:
     print("missing file")
     exit(1)
 
-with open(sys.argv[1]) as f:
+if sys.argv[1].startswith("http"):
+  f = urllib.request.urlopen(sys.argv[1])
+else:
+  f = open(sys.argv[1])
+with f:
     y = yaml.load(f, Loader=yaml.SafeLoader)
     schema = y["spec"]["validation"]["openAPIV3Schema"]
     schema = additional_properties(schema)