Added PluginError exception to make error handling nicer.

Also added a utility function to do HTTP requests.

7 files changed, 64 insertions, 36 deletions

diff --git a/src/livestreamer/__init__.py b/src/livestreamer/__init__.py
index 6a0b463..9eb2264 100644
--- a/src/livestreamer/__init__.py
+++ b/src/livestreamer/__init__.py
@@ -16,4 +16,7 @@ def resolve_url(url):
 def get_plugins():
     return plugins.get_plugins()
 
+
+PluginError = plugins.PluginError
+
 plugins.load_plugins(plugins)
diff --git a/src/livestreamer/cli.py b/src/livestreamer/cli.py
index 179b80d..6d7aac5 100644
--- a/src/livestreamer/cli.py
+++ b/src/livestreamer/cli.py
@@ -24,7 +24,10 @@ def handle_url(args):
     if not channel:
         exit(("No plugin can handle url: {0}").format(args.url))
 
-    streams = channel.get_streams()
+    try:
+        streams = channel.get_streams()
+    except livestreamer.PluginError as err:
+        exit(("Error from plugin while retrieving streams: {0}").format(err))
 
     if len(streams) == 0:
         exit(("No streams found on url: {0}").format(args.url))
diff --git a/src/livestreamer/plugins/__init__.py b/src/livestreamer/plugins/__init__.py
index fe62179..d24b4de 100644
--- a/src/livestreamer/plugins/__init__.py
+++ b/src/livestreamer/plugins/__init__.py
@@ -35,6 +35,9 @@ class Plugin(object):
     def _get_streams(self):
         raise NotImplementedError
 
+class PluginError(Exception):
+    pass
+
 def load_plugins(plugins):
     for loader, name, ispkg in pkgutil.iter_modules(plugins.__path__):
         file, pathname, desc = imp.find_module(name, plugins.__path__)
diff --git a/src/livestreamer/plugins/justintv.py b/src/livestreamer/plugins/justintv.py
index f8e4e0b..620db63 100644
--- a/src/livestreamer/plugins/justintv.py
+++ b/src/livestreamer/plugins/justintv.py
@@ -1,8 +1,8 @@
 #!/usr/bin/env python3
 
-from livestreamer.plugins import Plugin, register_plugin
+from livestreamer.plugins import Plugin, PluginError, register_plugin
 from livestreamer.stream import RTMPStream
-from livestreamer.utils import swfverify
+from livestreamer.utils import swfverify, urlget
 from livestreamer.compat import urllib, str
 
 import xml.dom.minidom, re, sys, random
@@ -28,11 +28,9 @@ class JustinTV(Plugin):
         self.cookie = args.jtv_cookie
 
     def _get_channel_name(self, url):
-        fd = urllib.urlopen(url)
-        data = fd.read()
-        fd.close()
-
+        data = urlget(url)
         match = re.search(b"live_facebook_embed_player\.swf\?channel=(\w+)", data)
+
         if match:
             return str(match.group(1), "ascii")
 
@@ -43,12 +41,13 @@ class JustinTV(Plugin):
         else:
             req = urllib.Request(self.MetadataURL.format(channel))
 
+        data = urlget(req)
 
-        fd = urllib.urlopen(req)
-        data = fd.read()
-        fd.close()
+        try:
+            dom = xml.dom.minidom.parseString(data)
+        except Exception as err:
+            raise PluginError(("Unable to parse config XML: {0})").format(err))
 
-        dom = xml.dom.minidom.parseString(data)
         meta = dom.getElementsByTagName("meta")[0]
         metadata = {}
 
@@ -80,19 +79,23 @@ class JustinTV(Plugin):
         randomp = int(random.random() * 999999)
 
         if "chansub_guid" in metadata:
-            fd = urllib.urlopen(self.StreamInfoURLSub.format(channelname, randomp, metadata["chansub_guid"]))
+            url = self.StreamInfoURLSub.format(channelname, randomp, metadata["chansub_guid"])
         else:
-            fd = urllib.urlopen(self.StreamInfoURL.format(channelname, randomp))
+            url = self.StreamInfoURL.format(channelname, randomp)
 
-        data = fd.read()
-        fd.close()
+        data = urlget(url)
 
         # fix invalid xml
         data = re.sub(b"<(\d+)", b"<_\g<1>", data)
         data = re.sub(b"</(\d+)", b"</_\g<1>", data)
 
         streams = {}
-        dom = xml.dom.minidom.parseString(data)
+
+        try:
+            dom = xml.dom.minidom.parseString(data)
+        except Exception as err:
+            raise PluginError(("Unable to parse config XML: {0})").format(err))
+
         nodes = dom.getElementsByTagName("nodes")[0]
 
         swfhash, swfsize = swfverify(self.SWFURL)
diff --git a/src/livestreamer/plugins/ownedtv.py b/src/livestreamer/plugins/ownedtv.py
index 6461c15..c15e8c4 100644
--- a/src/livestreamer/plugins/ownedtv.py
+++ b/src/livestreamer/plugins/ownedtv.py
@@ -1,8 +1,9 @@
 #!/usr/bin/env python3
 
-from livestreamer.plugins import Plugin, register_plugin
-from livestreamer.stream import RTMPStream
 from livestreamer.compat import urllib
+from livestreamer.plugins import Plugin, PluginError, register_plugin
+from livestreamer.stream import RTMPStream
+from livestreamer.utils import urlget
 
 import xml.dom.minidom, re
 
@@ -34,9 +35,7 @@ class OwnedTV(Plugin):
         return "own3d.tv" in url
 
     def _get_channel_id(self, url):
-        fd = urlopener.open(url)
-        data = fd.read()
-        fd.close()
+        data = urlget(url, opener=urlopener)
 
         match = re.search(b"document.location.hash='/live/(\d+)'", data)
         if match:
@@ -51,11 +50,13 @@ class OwnedTV(Plugin):
         streams = {}
 
         if channelid:
-            fd = urllib.urlopen(self.ConfigURL.format(channelid))
-            data = fd.read()
-            fd.close()
+            data = urlget(self.ConfigURL.format(channelid))
+
+            try:
+                dom = xml.dom.minidom.parseString(data)
+            except Exception as err:
+                raise PluginError(("Unable to parse config XML: {0})").format(err))
 
-            dom = xml.dom.minidom.parseString(data)
             channels = dom.getElementsByTagName("channels")[0]
             clip = channels.getElementsByTagName("clip")[0]
 
diff --git a/src/livestreamer/plugins/ustreamtv.py b/src/livestreamer/plugins/ustreamtv.py
index 63a3134..063923e 100644
--- a/src/livestreamer/plugins/ustreamtv.py
+++ b/src/livestreamer/plugins/ustreamtv.py
@@ -1,8 +1,9 @@
 #!/usr/bin/env python3
 
-from livestreamer.plugins import Plugin, register_plugin
+from livestreamer.compat import str, bytes
+from livestreamer.plugins import Plugin, PluginError, register_plugin
 from livestreamer.stream import RTMPStream
-from livestreamer.compat import urllib, str, bytes
+from livestreamer.utils import urlget
 
 import xml.dom.minidom, re
 
@@ -15,9 +16,7 @@ class UStreamTV(Plugin):
         return "ustream.tv" in url
 
     def _get_channel_id(self, url):
-        fd = urllib.urlopen(url)
-        data = fd.read()
-        fd.close()
+        data = urlget(url)
 
         match = re.search(b"channelId=(\d+)", data)
         if match:
@@ -34,9 +33,7 @@ class UStreamTV(Plugin):
         channelid = self._get_channel_id(self.url)
 
         if channelid:
-            fd = urllib.urlopen(self.AMFURL.format(channelid))
-            data = fd.read()
-            fd.close()
+            data = urlget(self.AMFURL.format(channelid))
 
             playpath = get_amf_value(data, "streamName")
             cdnurl = get_amf_value(data, "cdnUrl")
diff --git a/src/livestreamer/utils.py b/src/livestreamer/utils.py
index 60a4d6a..5ab8a63 100644
--- a/src/livestreamer/utils.py
+++ b/src/livestreamer/utils.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 
 from livestreamer.compat import urllib, bytes
+from livestreamer.plugins import PluginError
 import hmac, hashlib, zlib, argparse
 
 SWF_KEY = b"Genuine Adobe Flash Player 001"
@@ -36,10 +37,26 @@ class ArgumentParser(argparse.ArgumentParser):
         val = line[split+1:].strip()
         yield "--%s=%s" % (key, val)
 
+def urlget(url, data=None, timeout=None, opener=None):
+    try:
+        if opener is not None:
+            fd = opener.open(url)
+        else:
+            fd = urllib.urlopen(url, data, timeout)
+
+        data = fd.read()
+        fd.close()
+
+    except IOError as err:
+        if type(err) is urllib.URLError:
+            raise PluginError(err.reason)
+        else:
+            raise PluginError(err)
+
+    return data
+
 def swfverify(url):
-    fd = urllib.urlopen(url)
-    swf = fd.read()
-    fd.close()
+    swf = urlget(url)
 
     if swf[:3] == b"CWS":
         swf = b"F" + swf[1:8] + zlib.decompress(swf[8:])
@@ -47,3 +64,4 @@ def swfverify(url):
     h = hmac.new(SWF_KEY, swf, hashlib.sha256)
 
     return h.hexdigest(), len(swf)
+