Metalink: optimize size calculation (#582)

* optimize size calculation in metalink

* added metalink size tests

Author: cehbrecht

pywps/inout/basic.py

@@ -498,7 +498,7 @@ def post_data(self, value):
     @property
     def size(self):
         """Get content-length of URL without download"""
-        req = requests.head(self.url)
+        req = self._openurl(self.url)
         if req.ok:
             size = int(req.headers.get('content-length', '0'))
         else:

pywps/inout/outputs.py

@@ -320,6 +320,7 @@ def __init__(self, identity=None, description=None, fmt=None):
         The metalink document is created by a `MetaLink` instance, which
         holds a number of `MetaFile` instances.
         """
+        self._size = None
         self._output = ComplexOutput(
             identifier=identity or '',
             title=description or '',
@@ -360,8 +361,15 @@ def name(self):
 
     @property
     def size(self):
-        """Length of the linked content in octets."""
-        return self._output.size
+        """Size of the linked content in bytes."""
+        if self._size is None:
+            self._size = self._output.size
+        return self._size
+
+    @size.setter
+    def size(self, value):
+        """Set size to avoid size calculation."""
+        self._size = int(value)
 
     @property
     def urls(self):

tests/test_inout.py

@@ -832,6 +832,20 @@ def test_size(self):
         ml4.append(self.metafile_with_url())
         assert 'size' in ml4.xml
 
+    def test_no_size(self):
+        ml4 = self.metalink4()
+        mf = self.metafile_with_url()
+        mf.size = 0
+        ml4.files = [mf]
+        assert 'size' not in ml4.xml
+
+    def test_set_size(self):
+        ml4 = self.metalink4()
+        mf = self.metafile_with_url()
+        mf.size = 100
+        ml4.files = [mf]
+        assert '<size>100</size>' in ml4.xml
+
 
 def load_tests(loader=None, tests=None, pattern=None):
     if not loader: