Update install progress controller

Provide streaming updates to the UI during non blocking
commands. For the progress controller specifically this
is the output from curtin_wrap and subsequent curtin
execs.

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>

subiquity/controllers/installprogress.py

@@ -14,7 +14,9 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import logging
-import subprocess
+from tornado.gen import coroutine
+import subiquity.utils as utils
+from subiquity.models import InstallProgressModel
 from subiquity.ui.views import ProgressView, ProgressOutput
 from subiquity.controller import ControllerPolicy
 
@@ -22,9 +24,39 @@ log = logging.getLogger("subiquity.controller.installprogress")
 
 
 class InstallProgressController(ControllerPolicy):
-    def __init__(self, ui, signal):
+    def __init__(self, ui, signal, opts):
         self.ui = ui
         self.signal = signal
+        self.opts = opts
+        self.model = InstallProgressModel()
+        self.progress_output_w = ProgressOutput(
+            self.signal,
+            "Waiting...")
+
+    def exit_cb(self, ret):
+        log.debug("Exit: {}".format(ret))
+
+    @coroutine
+    def run_curtin(self):
+        try:
+            yield utils.run_command_async(
+                "/usr/local/bin/curtin_wrap.sh",
+                self.install_progress_status)
+        except Exception as e:
+            # TODO: Implement an Error View/Controller for displaying
+            # exceptions rather than kicking out of installer.
+            log.error("Problem running curtin_wrap: {}".format(e))
+
+    @coroutine
+    def run_test_curtin(self):
+        """ testing streaming output
+        """
+        self.install_progress_status("Starting run")
+        yield utils.run_command_async(
+            "cat /var/log/syslog",
+            self.install_progress_status)
+        log.debug("done")
+        return
 
     def install_progress(self):
         title = ("Installing system")
@@ -33,6 +65,7 @@ class InstallProgressController(ControllerPolicy):
         footer = ("Thank you for using Ubuntu!")
         self.ui.set_header(title, excerpt)
         self.ui.set_footer(footer)
+        self.ui.set_body(ProgressView(self.signal, self.progress_output_w))
         if self.opts.dry_run:
             log.debug("Filesystem: this is a dry-run")
             banner = [
@@ -43,15 +76,14 @@ class InstallProgressController(ControllerPolicy):
                 "",
                 "Press (Q) to Quit."
             ]
-            self.progress_output_w = ProgressOutput("\n".join(banner))
+            self.install_progress_status("\n".join(banner))
+            # XXX: Test routine to verify the callback streaming
+            # self.run_test_curtin()
         else:
             log.debug("filesystem: this is the *real* thing")
-            subprocess.Popen(["/usr/local/bin/curtin_wrap.sh"],
-                             stdout=self.install_progress_fd,
-                             bufsize=1,
-                             universal_newlines=True)
-            self.progress_output_w = ProgressOutput("Wait for it...\n\n")
-        self.ui.set_body(ProgressView(self.signal, self.progress_output_w))
+            self.run_curtin()
 
     def install_progress_status(self, data):
+        log.debug("Running status output: {}".format(data))
         self.progress_output_w.set_text(data)
+        self.signal.emit_signal('refresh')

subiquity/core.py

@@ -47,7 +47,8 @@ class Controller:
             "network": NetworkController(self.ui, self.signal),
             "filesystem": FilesystemController(self.ui, self.signal),
             "identity": IdentityController(self.ui, self.signal),
-            "progress": InstallProgressController(self.ui, self.signal),
+            "progress": InstallProgressController(self.ui, self.signal,
+                                                  self.opts)
         }
         self._connect_base_signals()
 
@@ -58,6 +59,7 @@ class Controller:
 
         # Add quit signal
         signals.append(('quit', self.exit))
+        signals.append(('refresh', self.redraw_screen))
         self.signal.connect_signals(signals)
 
         # Registers signals from each controller

subiquity/models/__init__.py

@@ -13,8 +13,9 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from .filesystem import FilesystemModel
-from .installpath import InstallpathModel
-from .network import NetworkModel
-from .welcome import WelcomeModel
-from .identity import IdentityModel
+from .filesystem import FilesystemModel  # NOQA
+from .installpath import InstallpathModel  # NOQA
+from .network import NetworkModel  # NOQA
+from .welcome import WelcomeModel  # NOQA
+from .identity import IdentityModel  # NOQA
+from .installprogress import InstallProgressModel  # NOQA

subiquity/models/installprogress.py

@@ -0,0 +1,47 @@
+# Copyright 2015 Canonical, Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+from subiquity.model import ModelPolicy
+
+
+log = logging.getLogger('subiquity.models.installprogress')
+
+
+class InstallProgressModel(ModelPolicy):
+    """ Model representing install progress
+    """
+    # FIXME: Decide what to do here if ESC is pressed, it's probably in
+    # a state of no return so may be better to just exit with error.
+    prev_signal = None
+
+    signals = [
+        ("Installprogress view",
+         'installprogress:show',
+         'install_progress')
+    ]
+
+    installprogress_menu = []
+
+    def get_signals(self):
+        return self.signals
+
+    def get_menu(self):
+        return self.installprogress_menu
+
+    def get_signal_by_name(self, selection):
+        for x, y, z in self.get_menu():
+            if x == selection:
+                return y

subiquity/ui/views/identity.py

@@ -73,7 +73,7 @@ class IdentityView(ViewPolicy):
             "confirm_password": self.confirm_password.value
         }
         log.debug("User input: {}".format(result))
-        # emit_signal(self.signal, 'installpath:show')
+        emit_signal(self.signal, 'installprogress:show')
 
     def cancel(self, button):
         self.signal.emit_signal("quit")

subiquity/ui/views/installprogress.py

@@ -13,27 +13,25 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from urwid import (Text, Filler, WidgetWrap,
+import logging
+from urwid import (Text, Filler,
                    ListBox, BoxAdapter)
 from subiquity.view import ViewPolicy
 from subiquity.ui.utils import Color, Padding
 
+log = logging.getLogger("subiquity.ui.views.installprogress")
 
-class ProgressOutput(WidgetWrap):
-    def __init__(self, txt):
+
+class ProgressOutput(ViewPolicy):
+    def __init__(self, signal, txt):
+        self.signal = signal
         self.txt = Text(txt)
         flr = Filler(Color.info_minor(self.txt),
-                     valign="bottom")
+                     valign="top")
         super().__init__(BoxAdapter(flr, height=20))
 
-    def split_text(self):
-        return self.txt.text.splitlines()
-
     def set_text(self, data):
-        data = data.decode("utf8")
-        lines = self.split_text() + data.splitlines()
-        out = "\n".join(lines[-20:])
-        self.txt.set_text(out)
+        self.txt.set_text(data)
 
 
 class ProgressView(ViewPolicy):
@@ -41,6 +39,7 @@ class ProgressView(ViewPolicy):
         """
         :param output_w: Filler widget to display updated status text
         """
+        self.signal = signal
         self.body = [
             Padding.center_79(output_w)
         ]