1 files changed, 72 insertions, 0 deletions
diff --git a/lib/spack/external/jsonschema/cli.py b/lib/spack/external/jsonschema/cli.py
new file mode 100644
index 0000000000..0126564f46
--- /dev/null
+++ b/lib/spack/external/jsonschema/cli.py
@@ -0,0 +1,72 @@
+from __future__ import absolute_import
+import argparse
+import json
+import sys
+
+from jsonschema._reflect import namedAny
+from jsonschema.validators import validator_for
+
+
+def _namedAnyWithDefault(name):
+    if "." not in name:
+        name = "jsonschema." + name
+    return namedAny(name)
+
+
+def _json_file(path):
+    with open(path) as file:
+        return json.load(file)
+
+
+parser = argparse.ArgumentParser(
+    description="JSON Schema Validation CLI",
+)
+parser.add_argument(
+    "-i", "--instance",
+    action="append",
+    dest="instances",
+    type=_json_file,
+    help="a path to a JSON instance to validate "
+         "(may be specified multiple times)",
+)
+parser.add_argument(
+    "-F", "--error-format",
+    default="{error.instance}: {error.message}\n",
+    help="the format to use for each error output message, specified in "
+         "a form suitable for passing to str.format, which will be called "
+         "with 'error' for each error",
+)
+parser.add_argument(
+    "-V", "--validator",
+    type=_namedAnyWithDefault,
+    help="the fully qualified object name of a validator to use, or, for "
+         "validators that are registered with jsonschema, simply the name "
+         "of the class.",
+)
+parser.add_argument(
+    "schema",
+    help="the JSON Schema to validate with",
+    type=_json_file,
+)
+
+
+def parse_args(args):
+    arguments = vars(parser.parse_args(args=args or ["--help"]))
+    if arguments["validator"] is None:
+        arguments["validator"] = validator_for(arguments["schema"])
+    return arguments
+
+
+def main(args=sys.argv[1:]):
+    sys.exit(run(arguments=parse_args(args=args)))
+
+
+def run(arguments, stdout=sys.stdout, stderr=sys.stderr):
+    error_format = arguments["error_format"]
+    validator = arguments["validator"](schema=arguments["schema"])
+    errored = False
+    for instance in arguments["instances"] or ():
+        for error in validator.iter_errors(instance):
+            stderr.write(error_format.format(error=error))
+            errored = True
+    return errored