basic validation of add-on results (aimed to aid development)

server.js

@@ -1,5 +1,6 @@
 var url = require("url");
 var rpc = require("./rpc");
+var validate = require("./validate"); // simply console-log warnings in case of wrong args; aimed to aid development
 var extend = require("extend");
 var async = require("async");
 
@@ -10,6 +11,8 @@ var CACHE_TTL = 2.5 * 60 * 60; // seconds to live for the cache
 
 var CENTRAL = "https://api9.strem.io";
 
+var IS_DEVEL = process.env.NODE_ENV !== "production";
+
 function Server(methods, options, manifest)
 {
 	var self = this;
@@ -66,7 +69,11 @@ function Server(methods, options, manifest)
 		var auth = params[0], // AUTH is obsolete
 			args = params[1] || { };
 
-		return methods[method](args, cb, { stremioget: true }); // everything is allowed without auth in stremioget mode
+		return methods[method](args, function(err, res) {
+			if (err) return cb(err);
+			if (IS_DEVEL) validate(method, res); // This would simply console-log warnings in case of wrong args; aimed to aid development
+			cb(null, res);
+		}, { stremioget: true }); // everything is allowed without auth in stremioget mode
 	};
 
 	// HTTP middleware

validate.js

@@ -0,0 +1,30 @@
+// simply console-log warnings in case of wrong args; aimed to aid development
+
+module.exports = function(method, res) {
+	if (method === "meta.find" || method === "stream.find") {
+		if (! Array.isArray(res)) warning('result from '+method+' is not an array, but should be, but is ',res)
+		else res.forEach(function(o) {
+			if (method === "meta.find") validateMetadata(o)
+			if (method === "stream.find") validateStream(o)
+		})
+	}
+
+	if (method === "meta.get") {
+		if (res) validateMetadata(res)
+	}
+}
+
+function warning(msg) {
+	console.log.apply(console, ['stremio-addons warning:'].concat(Array.prototype.slice.call(arguments)))
+}
+
+function validateMetadata(o) {
+	if (! o) warning('empty metadata object') 
+	else if (! o.id) warning('metadata object does not contain id')
+	else if (! o.type) warning('metadata object with id:'+o.id+' does not contain type')
+}
+
+function validateStream(o) {
+	if (! o) warning('empty stream object') 
+	else if (! (o.url || o.yt_id || o.infoHash)) warning('stream object does not contain any stremable property')
+}