Merge remote-tracking branch 'clebergnu/archive_uncompress_gz_v3'

Signed-off-by: NCaio Carrara <ccarrara@redhat.com>

avocado/utils/archive.py

@@ -15,6 +15,7 @@
 Module to help extract and create compressed archives.
 """
 
+import gzip
 import logging
 import os
 import platform
@@ -39,6 +40,37 @@ except ImportError:
         LZMA_CAPABLE = False
 
 
+#: The first two bytes that all gzip files start with
+GZIP_MAGIC = b'\037\213'
+
+
+def is_gzip_file(path):
+    """
+    Checks if file given by path has contents that suggests gzip file
+    """
+    with open(path, 'rb') as gzip_file:
+        return gzip_file.read(len(GZIP_MAGIC)) == GZIP_MAGIC
+
+
+def gzip_uncompress(path, output_path):
+    """
+    Uncompress a gzipped file at path, to either a file or dir at output_path
+    """
+    with gzip.GzipFile(filename=path, mode='rb') as input_file:
+        if os.path.isdir(output_path):
+            basename = os.path.basename(path)
+            if basename.endswith('.gz'):
+                basename = basename[:-3]
+            output_path = os.path.join(output_path, basename)
+        with open(output_path, 'wb') as output_file:
+            while True:
+                chunk = input_file.read(4096)
+                if not chunk:
+                    break
+                output_file.write(chunk)
+        return output_path
+
+
 class ArchiveException(Exception):
     """
     Base exception for all archive errors.
@@ -243,7 +275,8 @@ def is_archive(filename):
     :param filename: file to test.
     :return: `True` if it is an archive.
     """
-    return zipfile.is_zipfile(filename) or tarfile.is_tarfile(filename)
+    return (zipfile.is_zipfile(filename) or tarfile.is_tarfile(filename) or
+            is_gzip_file(filename))
 
 
 def compress(filename, path):
@@ -272,6 +305,9 @@ def uncompress(filename, path):
     :param filename: archive file name.
     :param path: destination path to extract to.
     """
+    if is_gzip_file(filename) and not tarfile.is_tarfile(filename):
+        return gzip_uncompress(filename, path)
+    else:
         with ArchiveFile.open(filename) as x:
             return x.extract(path)
 

selftests/unit/test_archive.py

@@ -155,6 +155,32 @@ class ArchiveTest(unittest.TestCase):
         self.assertEqual(ret, None, "Empty archive should return None (%s)"
                          % ret)
 
+    def test_is_gzip_file(self):
+        gz_path = os.path.join(BASEDIR, 'selftests', '.data', 'avocado.gz')
+        self.assertTrue(archive.is_gzip_file(gz_path))
+
+    def test_gzip_uncompress_to_dir(self):
+        gz_path = os.path.join(BASEDIR, 'selftests', '.data', 'avocado.gz')
+        ret = archive.gzip_uncompress(gz_path, self.decompressdir)
+        self.assertEqual(ret, os.path.join(self.decompressdir, 'avocado'))
+
+    def test_gzip_uncompress_to_file(self):
+        gz_path = os.path.join(BASEDIR, 'selftests', '.data', 'avocado.gz')
+        filename = os.path.join(self.decompressdir, 'other')
+        ret = archive.gzip_uncompress(gz_path, filename)
+        self.assertEqual(ret, filename)
+
+    def test_gzip_is_archive(self):
+        gz_path = os.path.join(BASEDIR, 'selftests', '.data', 'avocado.gz')
+        self.assertTrue(archive.is_archive(gz_path))
+
+    def test_uncompress_gzip(self):
+        gz_path = os.path.join(BASEDIR, 'selftests', '.data', 'avocado.gz')
+        ret = archive.uncompress(gz_path, self.decompressdir)
+        self.assertEqual(ret, os.path.join(self.decompressdir, 'avocado'))
+        with open(ret, 'rb') as decompressed:
+            self.assertEqual(decompressed.read(), b'avocado\n')
+
     def tearDown(self):
         try:
             shutil.rmtree(self.basedir)