Updated validation readme with python validator

.circleci/config.yml

@@ -35,4 +35,4 @@ jobs:
             python ~/stac-validator/stac_validator.py item-spec/examples/planet-sample.json
             python ~/stac-validator/stac_validator.py item-spec/examples/landsat8-sample.json
             python ~/stac-validator/stac_validator.py item-spec/examples/digitalglobe-sample.json
-            python ~/stac-validator/stac_validator.py item-spec/examples/CBERS_4_MUX_20170528_090_084_L2.json
+            python ~/stac-validator/stac_validator.py item-spec/examples/CBERS_4_MUX_20181029_177_106_L4.json

validation/README.md

@@ -1,10 +1,53 @@
 # STAC Schema Validation
 
+
 Any JSON Schema validation tool can be used, just run the JSON data to test against the various STAC schema, and be sure to include any remote schema like the geojson.json schema in the testing. 
 
-This directory includes installation instructions for a JavaScript validator, the following shows how to use it.
+This directory includes installation instructions for a Python validator and a JavaScript validator. The python validator is more complete and the recommnded tool for validation. The Javascript validator has been deprecated and will be removed in the next release.
+
+## Python Validator
+Install the validator from the [stac-validator](https://github.com/sparkgeo/stac-validator) repository and follow the instructions.
+
+The validator can be run as a command line tool and will report on nested catalogs as well as single items. There is no need to specifically identify 
+
+```
+stac_validator.py --help
+
+Description: Validate a STAC item or catalog against the STAC specification.
+
+Usage:
+    stac_validator.py <stac_file> [-version] [--verbose] [--timer]
+
+Arguments:
+    stac_file  Fully qualified path or url to a STAC file.
+
+Options:
+    -v, --version STAC_VERSION   Version to validate against. [default: master]
+    -h, --help                   Show this screen.
+    --verbose                    Verbose output. [default: False]
+    --timer                      Reports time to validate the STAC (seconds)
+
+
+stac_validator.py https://earth-stac.s3.amazonaws.com/eo/landsat-8-l1/catalog.json -v latest
+
+{
+    "catalogs": {
+        "valid": 1,
+        "invalid": 0
+    },
+    "collections": {
+        "valid": 0,
+        "invalid": 0
+    },
+    "items": {
+        "valid": 0,
+        "invalid": 0
+    }
+}
+```
 
-## Initialization
+## JavaScript Validator
+### Initialization
 
 In this directory run:
 
@@ -14,7 +57,7 @@ npm install
 
 This installs node.js validation modules, in a node_modules directory created in this directory.
 
-## Validation
+### Validation
 
 In the following chapter there are commands to run a validation of any STAC against the JSON Schema.