Start a new builder class

1 files changed, 328 insertions, 0 deletions

diff --git a/morphlib/builder2.py b/morphlib/builder2.py
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+++ b/morphlib/builder2.py
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+# Copyright (C) 2012  Codethink Limited
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; version 2 of the License.
+# 
+# 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 General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+
+import json
+import logging
+import os
+
+import morphlib
+
+
+class BuilderBase(object):
+
+    '''Base class for building artifacts.'''
+
+    def __init__(self, staging_area, artifact_cache, artifact, build_env, 
+                 max_jobs):
+        self.staging_area = staging_area
+        self.artifact_cache = artifact_cache
+        self.artifact = artifact
+        self.build_env = build_env
+        self.max_jobs = max_jobs
+    
+    def create_metadata(self, artifact_name):
+        '''Create metadata to artifact to allow it to be reproduced later.
+        
+        The metadata is represented as a dict, which later on will be
+        written out as a JSON file.
+        
+        '''
+        
+        meta = {
+            'artifact-name': artifact_name,
+            'source-name': self.artifact.source.morphology['name'],
+            'kind': self.artifact.source.morphology['kind'],
+            'description': self.artifact.source.morphology['description'],
+            'repo': self.artifact.source.repo,
+            'original_ref': self.artifact.source.original_ref,
+            'sha1': self.artifact.source.sha1,
+            'morphology': self.artifact.source.filename,
+        }
+        
+        return meta
+
+    # Wrapper around open() to allow it to be overridden by unit tests.
+    def _open(self, filename, mode): # pragma: no cover
+        dirname = os.path.dirname(filename)
+        if not os.path.exists(dirname):
+            os.makedirs(dirname)
+        return open(filename, mode)
+
+    def write_metadata(self, instdir, artifact_name):
+        '''Write the metadata for an artifact.
+        
+        The file will be located under the ``baserock`` directory under
+        instdir, named after ``cache_key`` with ``.meta`` as the suffix.
+        It will be in JSON format.
+        
+        '''
+        
+        meta = self.create_metadata(artifact_name)
+
+        basename = '%s.meta' % artifact_name
+        filename = os.path.join(instdir, 'baserock', basename)
+
+        # Unit tests use StringIO, which in Python 2.6 isn't usable with
+        # the "with" statement. So we don't do it with "with".
+        f = self._open(filename, 'w')
+        f.write(json.dumps(meta))
+        f.close()
+        
+    def new_artifact(self, artifact_name):
+        '''Return an Artifact object for something built from our source.'''
+        return morphlib.artifact.Artifact(self.artifact.source, artifact_name,
+                                          self.artifact.cache_key)
+        
+    def runcmd(self, *args, **kwargs):
+        return self.staging_area.runcmd(*args, **kwargs)
+
+
+class ChunkBuilder(BuilderBase):
+
+    '''Build chunk artifacts.'''
+    
+    def get_commands(self, which, morphology, build_system):
+        '''Return the commands to run from a morphology or the build system.'''
+        if morphology[which] is None:
+            attr = '_'.join(which.split('-'))
+            return getattr(build_system, attr)
+        else:
+            return morphology[which]
+
+    def build_and_cache(self): # pragma: no cover
+        destdir = self.staging_area.destdir(self.artifact.source)
+        self.run_commands(destdir)
+        self.assemble_chunk_artifacts(destdir)
+
+    def run_commands(self, destdir): # pragma: no cover
+        m = self.artifact.source.morphology
+        bs = morphlib.buildsystem.lookup_build_system(m['build-system'])
+
+        relative_destdir = self.staging_area.relative(destdir)
+        self.build_env.env['DESTDIR'] = relative_destdir
+
+        steps = [('configure', False), 
+                 ('build', True),
+                 ('test', False),
+                 ('install', False)]
+        for step, in_parallel in steps:
+            cmds = self.get_commands('%s-commands' % step, m, bs)
+            for cmd in cmds:
+                if in_parallel:
+                    max_jobs = self.artifact.source.morphology['max-jobs']
+                    if max_jobs is None:
+                        max_jobs = self.max_jobs
+                    self.build_env.env['MAKEFLAGS'] = '-j%s' % max_jobs
+                else:
+                    self.build_env.env['MAKEFLAGS'] = '-j1'
+                self.runcmd(['sh', '-c', cmd], cwd=relative_destdir)
+
+    def assemble_chunk_artifacts(self, destdir): # pragma: no cover
+        ex = None # create_chunk doesn't actually use this
+        specs = self.artifact.source.morphology['chunks']
+        if len(specs) == 0:
+            specs = {
+                self.artifact.source.morphology['name']: ['.'],
+            }
+        for artifact_name in specs:
+            self.write_metadata(destdir, artifact_name)
+            patterns = specs[artifact_name]
+            patterns += [r'baserock/%s\.' % artifact_name]
+
+            artifact = self.new_artifact(artifact_name)
+            with self.artifact_cache.put(artifact) as f:
+                logging.debug('assembling chunk %s' % artifact_name)
+                logging.debug('assembling into %s' % f.name)
+                morphlib.bins.create_chunk(destdir, f, patterns, ex)
+
+        files = os.listdir(destdir)
+        if files:
+            raise Exception('DESTDIR %s is not empty: %s' % (destdir, files))
+
+
+class StratumBuilder(BuilderBase):
+
+    '''Build stratum artifacts.'''
+
+    def build_and_cache(self): # pragma: no cover
+        destdir = self.staging_area.destdir(self.artifact.source)
+
+        constituents = [dependency
+                        for dependency in self.artifact.dependencies
+                        if dependency.source.morphology['kind'] == 'chunk']
+        for chunk_artifact in constituents:
+            with self.artifact_cache.get(chunk_artifact) as f:
+                morphlib.bins.unpack_binary_from_file(f, destdir)
+
+        artifact_name = self.artifact.source.morphology['name']
+        self.write_metadata(destdir, artifact_name)
+        artifact = self.new_artifact(artifact_name)
+        with self.artifact_cache.put(artifact) as f:
+            morphlib.bins.create_stratum(destdir, f, ex)
+
+
+class SystemBuilder(BuilderBase): # pragma: no cover
+
+    '''Build system image artifacts.'''
+
+    def build_and_cache(self):
+        logging.debug('SystemBuilder.do_build called')
+        self.ex = morphlib.execute.Execute(self.staging_area.dirname,
+                                           logging.debug)
+        
+        image_name = os.path.join(self.staging_area.dirname,
+                                  '%s.img' % self.artifact.name)
+        self._create_image(image_name)
+        self._partition_image(image_name)
+        self._install_mbr(image_name)
+        partition = self._setup_device_mapping(image_name)
+
+        mount_point = None
+        try:
+            self._create_fs(partition)
+            mount_point = self.staging_area.destdir(self.artifact.source)
+            self._mount(partition, mount_point)
+            factory_path = os.path.join(mount_point, 'factory')
+            self._create_subvolume(factory_path)
+            self._unpack_strata(factory_path)
+            self._create_fstab(factory_path)
+            self._create_extlinux_config(factory_path)
+            self._create_subvolume_snapshot(
+                    mount_point, 'factory', 'factory-run')
+            factory_run_path = os.path.join(mount_point, 'factory-run')
+            self._install_boot_files(factory_run_path, mount_point)
+            self._install_extlinux(mount_point)
+            self._unmount(mount_point)
+        except BaseException:
+            self._unmount(mount_point)
+            self._undo_device_mapping(image_name)
+            raise
+
+        self._undo_device_mapping(image_name)
+        self._move_image_to_cache(image_name)
+
+    def _create_image(self, image_name):
+        morphlib.fsutils.create_image(self.ex, image_name,
+                                      self.artifact.morphology['disk-size'])
+
+    def _partition_image(self, image_name):
+        morphlib.fsutils.partition_image(self.ex, image_name)
+
+    def _install_mbr(self, image_name):
+        morphlib.fsutils.install_mbr(self.ex, image_name)
+
+    def _setup_device_mapping(self, image_name):
+        return morphlib.fsutils.setup_device_mapping(self.ex, image_name)
+
+    def _create_fs(self, partition):
+        morphlib.fsutils.create_fs(self.ex, partition)
+
+    def _mount(self, partition, mount_point):
+        morphlib.fsutils.mount(self.ex, partition, mount_point)
+
+    def _create_subvolume(self, path):
+        self.ex.runv(['btrfs', 'subvolume', 'create', path])
+
+    def _unpack_strata(self, path):
+        for stratum_artifact in self.artifact.dependencies:
+            with self.artifact_cache.get(stratum_artifact) as f:
+                morphlib.bins.unpack_binary_from_file(f, path, self.ex)
+        morphlib.builder.ldconfig(self.ex, path)
+
+    def _create_fstab(self, path):
+        fstab = os.path.join(path, 'etc', 'fstab')
+        if not os.path.exists(os.path.dirname(fstab)): # FIXME: should exist
+            os.makedirs(os.path.dirname(fstab))
+        with open(fstab, 'w') as f:
+            f.write('proc      /proc proc  defaults          0 0\n')
+            f.write('sysfs     /sys  sysfs defaults          0 0\n')
+            f.write('/dev/sda1 / btrfs errors=remount-ro 0 1\n')
+
+    def _create_extlinux_config(self, path):
+        config = os.path.join(path, 'extlinux.conf')
+        with open(config, 'w') as f:
+            f.write('default linux\n')
+            f.write('timeout 1\n')
+            f.write('label linux\n')
+            f.write('kernel /boot/vmlinuz\n')
+            f.write('append root=/dev/sda1 rootflags=subvol=factory-run '
+                                           'init=/sbin/init quiet rw\n')
+
+    def _create_subvolume_snapshot(self, path, source, target):
+        self.ex.runv(['btrfs', 'subvolume', 'snapshot', source, target],
+                     cwd=path)
+
+    def _install_boot_files(self, sourcefs, targetfs):
+        logging.debug('installing boot files into root volume')
+        shutil.copy2(os.path.join(sourcefs, 'extlinux.conf'),
+                     os.path.join(targetfs, 'extlinux.conf'))
+        os.mkdir(os.path.join(targetfs, 'boot'))
+        shutil.copy2(os.path.join(sourcefs, 'boot', 'vmlinuz'),
+                     os.path.join(targetfs, 'boot', 'vmlinuz'))
+        shutil.copy2(os.path.join(sourcefs, 'boot', 'System.map'),
+                     os.path.join(targetfs, 'boot', 'System.map'))
+
+    def _install_extlinux(self, path):
+        self.ex.runv(['extlinux', '--install', path])
+
+        # FIXME this hack seems to be necessary to let extlinux finish
+        self.ex.runv(['sync'])
+        time.sleep(2)
+
+    def _unmount(self, mount_point):
+        if mount_point is not None:
+            morphlib.fsutils.unmount(self.ex, mount_point)
+
+    def _undo_device_mapping(self, image_name):
+        morphlib.fsutils.undo_device_mapping(self.ex, image_name)
+
+    def _move_image_to_cache(self, image_name):
+        # FIXME: Need to create file directly in cache to avoid costly
+        # copying here.
+        with self.artifact_cache.put(self.artifact) as outf:
+            with open(image_name) as inf:
+                while True:
+                    data = inf.read(1024**2)
+                    if not data:
+                        break
+                    outf.write(data)
+
+
+class Builder(object): # pragma: no cover
+
+    '''Helper class to build with the right BuilderBase subclass.'''
+    
+    classes = {
+        'chunk': ChunkBuilder,
+        'stratum': StratumBuilder,
+        'system': SystemBuilder,
+    }
+
+    def __init__(self, staging_area, artifact_cache, build_env, max_jobs):
+        self.staging_area = staging_area
+        self.artifact_cache = artifact_cache
+        self.build_env = build_env
+        self.max_jobs = max_jobs
+        
+    def build_and_cache(self, artifact):
+        kind = artifact.source.morphology['kind']
+        o = self.classes[kind](self.staging_area, self.artifact_cache, 
+                               artifact, self.build_env, self.max_jobs)
+        logging.debug('Builder.build: artifact %s with %s' %
+                      (artifact.name, repr(o)))
+        o.build_and_cache()
+        logging.debug('Builder.build: done')
+