Kill ffprobe after 30 seconds; add logging

lib/ffmpeg.js

@@ -4,9 +4,11 @@ var spawn = require("child_process").spawn;
 var https = require("https");
 var http = require("http");
 var urlparse = require("url");
+var path = require("path");
 require("status-message-polyfill");
 
 var USE_JSON = true;
+var TIMEOUT = 30000;
 
 var acceptedCodecs = {
     "mov/h264": true,
@@ -25,6 +27,15 @@ var audioOnlyContainers = {
     "mp3": true
 };
 
+function fflog() { }
+
+function initFFLog() {
+    var logger = new Logger.Logger(path.resolve(__dirname, "..", "ffmpeg.log"));
+    fflog = function () {
+        logger.log.apply(logger, arguments);
+    };
+}
+
 function testUrl(url, cb, redirCount) {
     if (!redirCount) redirCount = 0;
     var data = urlparse.parse(url);
@@ -137,12 +148,19 @@ function reformatData(data) {
 }
 
 exports.ffprobe = function ffprobe(filename, cb) {
+    fflog("Spawning ffprobe for " + filename);
     var childErr;
     var args = ["-show_streams", "-show_format", filename];
     if (USE_JSON) args = ["-of", "json"].concat(args);
     var child = spawn(Config.get("ffmpeg.ffprobe-exec"), args);
     var stdout = "";
     var stderr = "";
+    var timer = setTimeout(function () {
+        Logger.errlog.log("Possible runaway ffprobe process for file " + filename);
+        fflog("Killing ffprobe for " + filename + " after " + (TIMEOUT/1000) + " seconds");
+        childErr = new Error("File query exceeded time limit of 10 seconds");
+        child.kill('SIGKILL');
+    }, TIMEOUT);
 
     child.on("error", function (err) {
         childErr = err;
@@ -157,6 +175,8 @@ exports.ffprobe = function ffprobe(filename, cb) {
     });
 
     child.on("close", function (code) {
+        clearTimeout(timer);
+        fflog("ffprobe exited with code " + code + " for file " + filename);
         if (code !== 0) {
             if (stderr.match(/unrecognized option|json/i) && USE_JSON) {
                 Logger.errlog.log("Warning: ffprobe does not support -of json.  " +
@@ -189,6 +209,10 @@ exports.ffprobe = function ffprobe(filename, cb) {
 }
 
 exports.query = function (filename, cb) {
+    if (Config.get("ffmpeg.log")) {
+        initFFLog();
+    }
+
     if (!Config.get("ffmpeg.enabled")) {
         return cb("Raw file playback is not enabled on this server");
     }
@@ -215,6 +239,10 @@ exports.query = function (filename, cb) {
                         return cb("Link uses a protocol unsupported by this server's " +
                                   "version of ffmpeg");
 
+                    if (err.message.match(/exceeded time limit/)) {
+                        return cb(err.message);
+                    }
+
                     // Ignore ffprobe error messages, they are common and most often
                     // indicate a problem with the remote file, not with this code.
                     if (!/(av|ff)probe/.test(String(err)))