Implement snapcraft search (#608)

LP: #1596222

Signed-off-by: Sergio Schvezov <sergio.schvezov@ubuntu.com>

.bzrignore

@@ -15,3 +15,4 @@ dist
 htmlcov
 __pycache__
 docs/**.html
+*.swp

snapcraft/internal/common.py

@@ -212,6 +212,16 @@ def _search_and_replace_contents(file_path, search_pattern, replacement):
             f.write(replaced)
 
 
+def get_terminal_width(max_width=MAX_CHARACTERS_WRAP):
+    if os.isatty(sys.stdout.fileno()):
+        width = shutil.get_terminal_size().columns
+    else:
+        width = MAX_CHARACTERS_WRAP
+    if max_width:
+        width = min(max_width, width)
+    return width
+
+
 def format_output_in_columns(elements_list, max_width=MAX_CHARACTERS_WRAP,
                              num_col_spaces=2):
     """Return a formatted list of strings ready to be printed line by line

snapcraft/internal/parts.py

@@ -14,6 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import difflib
 import logging
 import os
 import sys
@@ -29,7 +30,13 @@
 )
 from xdg import BaseDirectory
 
+from snapcraft.internal.common import get_terminal_width
+
+
 PARTS_URI = 'https://parts.snapcraft.io/v1/parts.yaml'
+_MATCH_RATIO = 0.6
+_HEADER_PART_NAME = 'PART NAME'
+_HEADER_DESCRIPTION = 'DESCRIPTION'
 
 logging.getLogger("urllib3").setLevel(logging.CRITICAL)
 logger = logging.getLogger(__name__)
@@ -117,6 +124,22 @@ def get_part(self, part_name, full=False):
                 remote_part.pop(key)
         return remote_part
 
+    def matches_for(self, part_match, max_len=0):
+        matcher = difflib.SequenceMatcher(isjunk=None, autojunk=False)
+        matcher.set_seq2(part_match)
+
+        matching_parts = {}
+        for part_name in self._parts.keys():
+            matcher.set_seq1(part_name)
+            add_part_name = matcher.ratio() >= _MATCH_RATIO
+
+            if add_part_name or (part_match in part_name):
+                matching_parts[part_name] = self._parts[part_name]
+                if len(part_name) > max_len:
+                    max_len = len(part_name)
+
+        return matching_parts, max_len
+
     def compose(self, part_name, properties):
         """Return properties composed with the ones from part name in the wiki.
         :param str part_name: The name of the part to query from the wiki
@@ -151,5 +174,30 @@ def define(part_name):
               default_flow_style=False, stream=sys.stdout)
 
 
+def search(part_match):
+    header_len = len(_HEADER_PART_NAME)
+    matches, part_length = _RemoteParts().matches_for(part_match, header_len)
+
+    terminal_width = get_terminal_width(max_width=None)
+    part_length = max(part_length, header_len)
+    # <space> + <space> + <description> + ... = 5
+    description_space = terminal_width - part_length - 5
+
+    if not matches:
+        # apt search does not return error, we probably shouldn't either.
+        logger.info('No matches found, try to run `snapcraft update` to '
+                    'refresh the remote parts cache.')
+        return
+
+    print('{}  {}'.format(
+        _HEADER_PART_NAME.ljust(part_length, ' '), _HEADER_DESCRIPTION))
+    for part_key in matches.keys():
+        description = matches[part_key]['description']
+        if len(description) > description_space:
+            description = '{}...'.format(description[0:description_space])
+        print('{}  {}'.format(
+            part_key.ljust(part_length, ' '), description))
+
+
 def get_remote_parts():
     return _RemoteParts()

snapcraft/main.py

@@ -37,6 +37,7 @@
   snapcraft [options] tour [<directory>]
   snapcraft [options] update
   snapcraft [options] define <part-name>
+  snapcraft [options] search [<query> ...]
   snapcraft [options] help (topics | <plugin> | <topic>) [--devel]
   snapcraft (-h | --help)
   snapcraft --version
@@ -93,6 +94,7 @@
 Parts ecosystem commands
   update       Updates the parts listing from the cloud.
   define       Shows the definition for the cloud part.
+  search       Searches the remotes part cache for matching parts.
 
 Calling snapcraft without a COMMAND will default to 'snap'
 
@@ -106,22 +108,22 @@
 http://developer.ubuntu.com/snappy/snapcraft
 """
 
-from contextlib import suppress
 import logging
 import os
 import pkg_resources
 import pkgutil
 import shutil
 import sys
-import subprocess
 import textwrap
 
 from docopt import docopt
 
 import snapcraft
 from snapcraft.internal import lifecycle, log, parts
 from snapcraft.internal.common import (
-    format_output_in_columns, MAX_CHARACTERS_WRAP, get_tourdir)
+    format_output_in_columns,
+    get_terminal_width,
+    get_tourdir)
 
 
 logger = logging.getLogger(__name__)
@@ -169,16 +171,7 @@ def _list_plugins():
         plugins.append(modname.replace('_', '-'))
 
     # we wrap the output depending on terminal size
-    width = MAX_CHARACTERS_WRAP
-    with suppress(OSError):
-        with suppress(subprocess.CalledProcessError):
-            # this is the only way to get current terminal size reliably
-            # without duplicating a bunch of logic
-            command = ['tput', 'cols']
-            candidate_width = \
-                subprocess.check_output(command, stderr=subprocess.DEVNULL)
-            width = min(int(candidate_width), width)
-
+    width = get_terminal_width()
     for line in format_output_in_columns(plugins, max_width=width):
         print(line)
 
@@ -260,6 +253,8 @@ def run(args, project_options):  # noqa
         parts.update()
     elif args['define']:
         parts.define(args['<part-name>'])
+    elif args['search']:
+        parts.search(' '.join(args['<query>']))
     else:  # snap by default:
         lifecycle.snap(project_options, args['<directory>'], args['--output'])
 

snapcraft/tests/fake_servers.py

@@ -64,10 +64,16 @@ def do_GET(self):
                     'description': 'test entry for part1',
                     'maintainer': 'none',
                 },
+                'long-described-part': {
+                    'plugin': 'go',
+                    'source': 'http://source.tar.gz',
+                    'description': 'this is a repetitive description ' * 3,
+                    'maintainer': 'none',
+                },
             }
         self.send_header('Content-Type', 'text/plain')
         if 'NO_CONTENT_LENGTH' not in os.environ:
-            self.send_header('Content-Length', '300')
+            self.send_header('Content-Length', '1000')
         self.send_header('ETag', '1111')
         self.end_headers()
         self.wfile.write(yaml.dump(response).encode())

snapcraft/tests/fixture_setup.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
+import io
 import threading
 import urllib.parse
 from unittest import mock
@@ -79,6 +80,44 @@ def setUp(self):
         self.addCleanup(os.environ.update, current_environment)
 
 
+class _FakeStdout(io.StringIO):
+    """A fake stdout using StringIO implementing the missing fileno attrib."""
+
+    def fileno(self):
+        return 1
+
+
+class _FakeTerminalSize:
+
+    def __init__(self, columns=80):
+        self.columns = columns
+
+
+class FakeTerminal(fixtures.Fixture):
+
+    def __init__(self, columns=80, isatty=True):
+        self.columns = columns
+        self.isatty = isatty
+
+    def _setUp(self):
+        patcher = mock.patch('shutil.get_terminal_size')
+        mock_terminal_size = patcher.start()
+        mock_terminal_size.return_value = _FakeTerminalSize(self.columns)
+        self.addCleanup(patcher.stop)
+
+        patcher = mock.patch('sys.stdout', new_callable=_FakeStdout)
+        self.mock_stdout = patcher.start()
+        self.addCleanup(patcher.stop)
+
+        patcher = mock.patch('os.isatty')
+        mock_isatty = patcher.start()
+        mock_isatty.return_value = self.isatty
+        self.addCleanup(patcher.stop)
+
+    def getvalue(self):
+        return self.mock_stdout.getvalue()
+
+
 class FakeParts(fixtures.Fixture):
 
     def setUp(self):

snapcraft/tests/test_commands_list_plugins.py

@@ -14,12 +14,9 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import io
-import subprocess
-from unittest import mock
-
 from snapcraft.main import main
 from snapcraft import tests
+from snapcraft.tests import fixture_setup
 
 
 class ListPluginsCommandTestCase(tests.TestCase):
@@ -31,41 +28,28 @@ class ListPluginsCommandTestCase(tests.TestCase):
         'autotools  cmake   go    jdk   kernel  maven  nodejs  python3  '
         'scons\n')
 
-    @mock.patch('sys.stdout', new_callable=io.StringIO)
-    @mock.patch('subprocess.check_output')
-    def test_list_plugins_large_terminal(self, mock_subprocess, mock_stdout):
-        mock_subprocess.return_value = "999"
+    def test_list_plugins_non_tty(self):
+        fake_terminal = fixture_setup.FakeTerminal(isatty=False)
+        self.useFixture(fake_terminal)
+
+        main(['list-plugins'])
+        self.assertEqual(fake_terminal.getvalue(), self.default_plugin_output)
+
+    def test_list_plugins_large_terminal(self):
+        fake_terminal = fixture_setup.FakeTerminal(columns=999)
+        self.useFixture(fake_terminal)
+
         main(['list-plugins'])
-        self.assertEqual(mock_stdout.getvalue(), self.default_plugin_output)
+        self.assertEqual(fake_terminal.getvalue(), self.default_plugin_output)
+
+    def test_list_plugins_small_terminal(self):
+        fake_terminal = fixture_setup.FakeTerminal(columns=60)
+        self.useFixture(fake_terminal)
 
-    @mock.patch('sys.stdout', new_callable=io.StringIO)
-    @mock.patch('subprocess.check_output')
-    def test_list_plugins_small_terminal(self, mock_subprocess, mock_stdout):
-        mock_subprocess.return_value = "60"
         expected_output = (
             'ant        copy  kbuild  nil      qmake      \n'
             'autotools  go    kernel  nodejs   scons      \n'
             'catkin     gulp  make    python2  tar-content\n'
             'cmake      jdk   maven   python3\n')
         main(['list-plugins'])
-        self.assertEqual(mock_stdout.getvalue(), expected_output)
-
-    @mock.patch('sys.stdout', new_callable=io.StringIO)
-    @mock.patch('subprocess.check_output')
-    def test_list_plugins_error_invalid_terminal_size(self, mock_subprocess,
-                                                      mock_stdout):
-        def raise_error(cmd, stderr):
-            raise OSError()
-        mock_subprocess.side_effect = raise_error
-        main(['list-plugins'])
-        self.assertEqual(mock_stdout.getvalue(), self.default_plugin_output)
-
-    @mock.patch('sys.stdout', new_callable=io.StringIO)
-    @mock.patch('subprocess.check_output')
-    def test_list_plugins_error_invalid_subprocess_call(self, mock_subprocess,
-                                                        mock_stdout):
-        def raise_error(cmd, stderr):
-            raise subprocess.CalledProcessError(returncode=1, cmd=cmd)
-        mock_subprocess.side_effect = raise_error
-        main(['list-plugins'])
-        self.assertEqual(mock_stdout.getvalue(), self.default_plugin_output)
+        self.assertEqual(fake_terminal.getvalue(), expected_output)