support for stdin

TurtleValidator.js

@@ -1,27 +1,22 @@
 #!/usr/bin/env node
 
-var N3 = require('n3'), fs = require('fs'), N3Util = N3.Util;
+var N3 = require('n3'),
+    fs = require('fs'),
+    N3Util = N3.Util,
+    http = require('http'),
+    fs = require('fs');
 
-if (!process.argv[2]) {
-	console.log('RDF N3/NTriples/Turtle file validator');
-	console.log('Usage: $ ttl <path-to-file>');
-	process.exit(1);
-}
-
-console.log('Validating ' + process.argv[2]);
-
-var parser = N3.Parser(), turtleStream = fs.createReadStream(process.argv[2]);
-
-var errorCount = 0, warningCount = 0;
-
-var regexp = {
+var validateStream = function (turtleStream) {
+  var parser = N3.Parser();
+  var errorCount = 0, warningCount = 0;
+  var regexp = {
     'dateTime' : /^(-?(?:[1-9][0-9]*)?[0-9]{4})-(1[0-2]|0[1-9])-(3[0-1]|0[1-9]|[1-2][0-9])?T(2[0-3]|[0-1][0-9]):([0-5][0-9]):([0-5][0-9])(\.[0-9]+)??(Z|[+-](?:2[0-3]|[0-1][0-9]):[0-5][0-9])?$/,
     'double' : /[-+]?\d*([.]\d+)?/,
     'float' : /[-+]?\d*[.]\d+/,
     'int' : /^[-+]?(0|[1-9]\d*)$/
-};
+  };
 
-parser.parse(turtleStream, function(error, triple, prefixes) {
+  parser.parse(turtleStream, function(error, triple, prefixes) {
     if (error) {
       console.log(error);
       errorCount++;
@@ -42,4 +37,48 @@ parser.parse(turtleStream, function(error, triple, prefixes) {
     } else {
       console.log('Validation done:', errorCount, 'errors and', warningCount ,'warnings found.');
     }
-});
+  });
+};
+
+var help = function () {
+  // In all other cases, let's help the user and return some help
+  console.log('RDF NTriples/Turtle validator using Ruben Verborgh\'s N3 nodejs library');
+  console.log('© 2014 - MMLab - Ghent University - iMinds');
+  console.log('Source code: https://github.com/MMLab/TurtleValidator');
+  console.log('');
+  console.log('Examples:');
+  console.log('');
+  console.log('  $ ttl <path-to-file>');
+  console.log('  $ curl http://data.linkeddatafragments.org/dbpedia -H "accept: text/turtle" | ttl');
+  console.log('  $ ttl http://triples.demo.thedatatank.com/demo.ttl');
+};
+
+if (process.argv[2] && (process.argv[2] === "-h" || process.argv[2] === "--help") ) {
+  help();
+} else if (process.argv.length === 2) {
+  // Use stdio as an input stream
+  validateStream(process.stdin);
+} else if (process.argv.length === 3 ) {
+  // Create a stream from the file, whether it is a local file or a http stream
+  var filename = process.argv[2];
+  fs.exists(filename, function (exists) {
+    if (exists) {
+      try{
+        validateStream(fs.createReadStream(filename));
+      } catch ( e ) {
+        console.error(e);
+      } 
+    } else {
+      try{
+        validateStream(http.get(process.argv[2]));
+      } catch ( e ) {
+        console.error(e);
+      }
+    }
+  });
+
+} else {
+  help();
+}
+
+

package.json

@@ -3,7 +3,9 @@
   "version": "0.1.0",
   "description": "This command line tool validates Turtle documents and does XSD datatype checks",
   "main": "TurtleValidator.js",
-  "bin" : { "ttl" : "./TurtleValidator.js" },
+  "bin": {
+    "ttl": "./TurtleValidator.js"
+  },
   "dependencies": {
     "n3": "~0.2.6"
   },