models.py

# -*- coding: utf-8 -*-
"""Models for the builds app."""

from __future__ import (
    absolute_import,
    division,
    print_function,
    unicode_literals,
)

import logging
import os.path
import re
from shutil import rmtree

from builtins import object
from django.conf import settings
from django.core.urlresolvers import reverse
from django.db import models
from django.utils import timezone
from django.utils.encoding import python_2_unicode_compatible
from django.utils.translation import ugettext
from django.utils.translation import ugettext_lazy as _
from guardian.shortcuts import assign
from jsonfield import JSONField
from taggit.managers import TaggableManager

from readthedocs.core.utils import broadcast
from readthedocs.projects.constants import (
    BITBUCKET_URL,
    GITHUB_URL,
    GITLAB_URL,
    PRIVACY_CHOICES,
    PRIVATE,
)
from readthedocs.projects.models import APIProject, Project

from .constants import (
    BRANCH,
    BUILD_STATE,
    BUILD_STATE_FINISHED,
    BUILD_TYPES,
    LATEST,
    NON_REPOSITORY_VERSIONS,
    STABLE,
    TAG,
    VERSION_TYPES,
)
from .managers import VersionManager
from .querysets import BuildQuerySet, RelatedBuildQuerySet, VersionQuerySet
from .utils import (
    get_bitbucket_username_repo,
    get_github_username_repo,
    get_gitlab_username_repo,
)
from .version_slug import VersionSlugField

DEFAULT_VERSION_PRIVACY_LEVEL = getattr(
    settings, 'DEFAULT_VERSION_PRIVACY_LEVEL', 'public')

log = logging.getLogger(__name__)


@python_2_unicode_compatible
class Version(models.Model):

    """Version of a ``Project``."""

    project = models.ForeignKey(
        Project,
        verbose_name=_('Project'),
        related_name='versions',
    )
    type = models.CharField(
        _('Type'),
        max_length=20,
        choices=VERSION_TYPES,
        default='unknown',
    )
    # used by the vcs backend

    #: The identifier is the ID for the revision this is version is for. This
    #: might be the revision number (e.g. in SVN), or the commit hash (e.g. in
    #: Git). If the this version is pointing to a branch, then ``identifier``
    #: will contain the branch name.
    identifier = models.CharField(_('Identifier'), max_length=255)

    #: This is the actual name that we got for the commit stored in
    #: ``identifier``. This might be the tag or branch name like ``"v1.0.4"``.
    #: However this might also hold special version names like ``"latest"``
    #: and ``"stable"``.
    verbose_name = models.CharField(_('Verbose Name'), max_length=255)

    #: The slug is the slugified version of ``verbose_name`` that can be used
    #: in the URL to identify this version in a project. It's also used in the
    #: filesystem to determine how the paths for this version are called. It
    #: must not be used for any other identifying purposes.
    slug = VersionSlugField(
        _('Slug'), max_length=255, populate_from='verbose_name')

    supported = models.BooleanField(_('Supported'), default=True)
    active = models.BooleanField(_('Active'), default=False)
    built = models.BooleanField(_('Built'), default=False)
    uploaded = models.BooleanField(_('Uploaded'), default=False)
    privacy_level = models.CharField(
        _('Privacy Level'),
        max_length=20,
        choices=PRIVACY_CHOICES,
        default=DEFAULT_VERSION_PRIVACY_LEVEL,
        help_text=_('Level of privacy for this Version.'),
    )
    tags = TaggableManager(blank=True)
    machine = models.BooleanField(_('Machine Created'), default=False)

    objects = VersionManager.from_queryset(VersionQuerySet)()

    class Meta(object):
        unique_together = [('project', 'slug')]
        ordering = ['-verbose_name']
        permissions = (
            # Translators: Permission around whether a user can view the
            #              version
            ('view_version', _('View Version')),)

    def __str__(self):
        return ugettext(
            'Version {version} of {project} ({pk})'.format(
                version=self.verbose_name,
                project=self.project,
                pk=self.pk,
            ))

    @property
    def config(self):
        """Returns the configuration used in the last successful build."""
        last_build = (
            self.builds.filter(state='finished', success=True)
            .order_by('-date')
            .first()
        )
        return last_build.get_config()

    @property
    def commit_name(self):
        """
        Return the branch name, the tag name or the revision identifier.

        The result could be used as ref in a git repo, e.g. for linking to
        GitHub, Bitbucket or GitLab.
        """
        # LATEST is special as it is usually a branch but does not contain the
        # name in verbose_name.
        if self.slug == LATEST:
            if self.project.default_branch:
                return self.project.default_branch
            return self.project.vcs_repo().fallback_branch

        if self.slug == STABLE:
            if self.type == BRANCH:
                # Special case, as we do not store the original branch name
                # that the stable version works on. We can only interpolate the
                # name from the commit identifier, but it's hacky.
                # TODO: Refactor ``Version`` to store more actual info about
                # the underlying commits.
                if self.identifier.startswith('origin/'):
                    return self.identifier[len('origin/'):]
            return self.identifier

        # By now we must have handled all special versions.
        assert self.slug not in NON_REPOSITORY_VERSIONS

        if self.type in (BRANCH, TAG):
            # If this version is a branch or a tag, the verbose_name will
            # contain the actual name. We cannot use identifier as this might
            # include the "origin/..." part in the case of a branch. A tag
            # would contain the hash in identifier, which is not as pretty as
            # the actual tag name.
            return self.verbose_name

        # If we came that far it's not a special version nor a branch or tag.
        # Therefore just return the identifier to make a safe guess.
        log.debug('TODO: Raise an exception here. Testing what cases it happens')
        return self.identifier

    def get_absolute_url(self):
        if not self.built and not self.uploaded:
            return reverse(
                'project_version_detail',
                kwargs={
                    'project_slug': self.project.slug,
                    'version_slug': self.slug,
                },
            )
        private = self.privacy_level == PRIVATE
        return self.project.get_docs_url(
            version_slug=self.slug, private=private)

    def save(self, *args, **kwargs):  # pylint: disable=arguments-differ
        """Add permissions to the Version for all owners on save."""
        from readthedocs.projects import tasks
        obj = super(Version, self).save(*args, **kwargs)
        for owner in self.project.users.all():
            assign('view_version', owner, self)
        try:
            self.project.sync_supported_versions()
        except Exception:
            log.exception('failed to sync supported versions')
        broadcast(
            type='app', task=tasks.symlink_project, args=[self.project.pk])
        return obj

    def delete(self, *args, **kwargs):  # pylint: disable=arguments-differ
        from readthedocs.projects import tasks
        log.info('Removing files for version %s', self.slug)
        broadcast(type='app', task=tasks.clear_artifacts, args=[self.get_artifact_paths()])
        broadcast(
            type='app', task=tasks.symlink_project, args=[self.project.pk])
        super(Version, self).delete(*args, **kwargs)

    @property
    def identifier_friendly(self):
        """Return display friendly identifier."""
        if re.match(r'^[0-9a-f]{40}$', self.identifier, re.I):
            return self.identifier[:8]
        return self.identifier

    def get_subdomain_url(self):
        private = self.privacy_level == PRIVATE
        return self.project.get_docs_url(
            version_slug=self.slug,
            lang_slug=self.project.language,
            private=private,
        )

    def get_downloads(self, pretty=False):
        project = self.project
        data = {}
        if pretty:
            if project.has_pdf(self.slug):
                data['PDF'] = project.get_production_media_url('pdf', self.slug)
            if project.has_htmlzip(self.slug):
                data['HTML'] = project.get_production_media_url(
                    'htmlzip', self.slug)
            if project.has_epub(self.slug):
                data['Epub'] = project.get_production_media_url(
                    'epub', self.slug)
        else:
            if project.has_pdf(self.slug):
                data['pdf'] = project.get_production_media_url('pdf', self.slug)
            if project.has_htmlzip(self.slug):
                data['htmlzip'] = project.get_production_media_url(
                    'htmlzip', self.slug)
            if project.has_epub(self.slug):
                data['epub'] = project.get_production_media_url(
                    'epub', self.slug)
        return data

    def get_conf_py_path(self):
        conf_py_path = self.project.conf_dir(self.slug)
        checkout_prefix = self.project.checkout_path(self.slug)
        conf_py_path = os.path.relpath(conf_py_path, checkout_prefix)
        return conf_py_path

    def get_build_path(self):
        """Return version build path if path exists, otherwise `None`."""
        path = self.project.checkout_path(version=self.slug)
        if os.path.exists(path):
            return path
        return None

    def get_artifact_paths(self):
        """
        Return a list of all production artifacts/media path for this version.

        :rtype: list
        """
        paths = []

        for type_ in ('pdf', 'epub', 'htmlzip'):
            paths.append(
                self.project.get_production_media_path(
                    type_=type_,
                    version_slug=self.slug),
            )
        paths.append(self.project.rtd_build_path(version=self.slug))

        return paths

    def clean_build_path(self):
        """
        Clean build path for project version.

        Ensure build path is clean for project version. Used to ensure stale
        build checkouts for each project version are removed.
        """
        try:
            path = self.get_build_path()
            if path is not None:
                log.debug('Removing build path %s for %s', path, self)
                rmtree(path)
        except OSError:
            log.exception('Build path cleanup failed')

    def get_github_url(
            self, docroot, filename, source_suffix='.rst', action='view'):
        """
        Return a GitHub URL for a given filename.

        :param docroot: Location of documentation in repository
        :param filename: Name of file
        :param source_suffix: File suffix of documentation format
        :param action: `view` (default) or `edit`
        """
        repo_url = self.project.repo
        if 'github' not in repo_url:
            return ''

        if not docroot:
            return ''

        if docroot[0] != '/':
            docroot = '/{}'.format(docroot)
        if docroot[-1] != '/':
            docroot = '{}/'.format(docroot)

        if action == 'view':
            action_string = 'blob'
        elif action == 'edit':
            action_string = 'edit'

        user, repo = get_github_username_repo(repo_url)
        if not user and not repo:
            return ''
        repo = repo.rstrip('/')

        return GITHUB_URL.format(
            user=user,
            repo=repo,
            version=self.commit_name,
            docroot=docroot,
            path=filename,
            source_suffix=source_suffix,
            action=action_string,
        )

    def get_gitlab_url(
            self, docroot, filename, source_suffix='.rst', action='view'):
        repo_url = self.project.repo
        if 'gitlab' not in repo_url:
            return ''

        if not docroot:
            return ''

        if docroot[0] != '/':
            docroot = '/{}'.format(docroot)
        if docroot[-1] != '/':
            docroot = '{}/'.format(docroot)

        if action == 'view':
            action_string = 'blob'
        elif action == 'edit':
            action_string = 'edit'

        user, repo = get_gitlab_username_repo(repo_url)
        if not user and not repo:
            return ''
        repo = repo.rstrip('/')

        return GITLAB_URL.format(
            user=user,
            repo=repo,
            version=self.commit_name,
            docroot=docroot,
            path=filename,
            source_suffix=source_suffix,
            action=action_string,
        )

    def get_bitbucket_url(self, docroot, filename, source_suffix='.rst'):
        repo_url = self.project.repo
        if 'bitbucket' not in repo_url:
            return ''
        if not docroot:
            return ''

        user, repo = get_bitbucket_username_repo(repo_url)
        if not user and not repo:
            return ''
        repo = repo.rstrip('/')

        return BITBUCKET_URL.format(
            user=user,
            repo=repo,
            version=self.commit_name,
            docroot=docroot,
            path=filename,
            source_suffix=source_suffix,
        )


class APIVersion(Version):

    """
    Version proxy model for API data deserialization.

    This replaces the pattern where API data was deserialized into a mocked
    :py:class:`Version` object.
    This pattern was confusing, as it was not explicit
    as to what form of object you were working with -- API backed or database
    backed.

    This model preserves the Version model methods, allowing for overrides on
    model field differences. This model pattern will generally only be used on
    builder instances, where we are interacting solely with API data.
    """

    project = None

    class Meta:
        proxy = True

    def __init__(self, *args, **kwargs):
        self.project = APIProject(**kwargs.pop('project', {}))
        # These fields only exist on the API return, not on the model, so we'll
        # remove them to avoid throwing exceptions due to unexpected fields
        for key in ['resource_uri', 'absolute_url', 'downloads']:
            try:
                del kwargs[key]
            except KeyError:
                pass
        super(APIVersion, self).__init__(*args, **kwargs)

    def save(self, *args, **kwargs):
        return 0


@python_2_unicode_compatible
class VersionAlias(models.Model):

    """Alias for a ``Version``."""

    project = models.ForeignKey(
        Project, verbose_name=_('Project'), related_name='aliases')
    from_slug = models.CharField(_('From slug'), max_length=255, default='')
    to_slug = models.CharField(
        _('To slug'), max_length=255, default='', blank=True)
    largest = models.BooleanField(_('Largest'), default=False)

    def __str__(self):
        return ugettext(
            'Alias for {project}: {_from} -> {to}'.format(
                project=self.project,
                _from=self.from_slug,
                to=self.to_slug,
            ))


@python_2_unicode_compatible
class Build(models.Model):

    """Build data."""

    project = models.ForeignKey(
        Project, verbose_name=_('Project'), related_name='builds')
    version = models.ForeignKey(
        Version, verbose_name=_('Version'), null=True, related_name='builds')
    type = models.CharField(
        _('Type'), max_length=55, choices=BUILD_TYPES, default='html')
    state = models.CharField(
        _('State'), max_length=55, choices=BUILD_STATE, default='finished')
    date = models.DateTimeField(_('Date'), auto_now_add=True)
    success = models.BooleanField(_('Success'), default=True)

    setup = models.TextField(_('Setup'), null=True, blank=True)
    setup_error = models.TextField(_('Setup error'), null=True, blank=True)
    output = models.TextField(_('Output'), default='', blank=True)
    error = models.TextField(_('Error'), default='', blank=True)
    exit_code = models.IntegerField(_('Exit code'), null=True, blank=True)
    commit = models.CharField(
        _('Commit'), max_length=255, null=True, blank=True)
    config = JSONField(_('Configuration used in the build'), default=dict)

    length = models.IntegerField(_('Build Length'), null=True, blank=True)

    builder = models.CharField(
        _('Builder'), max_length=255, null=True, blank=True)

    cold_storage = models.NullBooleanField(
        _('Cold Storage'), help_text='Build steps stored outside the database.')

    # Manager

    objects = BuildQuerySet.as_manager()

    class Meta(object):
        ordering = ['-date']
        get_latest_by = 'date'
        index_together = [['version', 'state', 'type']]

    @property
    def previous(self):
        """Returns the previous build to this one."""
        date = self.date or timezone.now()
        if self.project is not None and self.version is not None:
            return (
                Build.objects
                .filter(
                    project=self.project,
                    version=self.version,
                    date__lt=date,
                )
                .order_by('-date')
                .first()
            )
        return None

    def get_config(self):
        """Get the config from correct object."""
        if '__config' in self.config:
            return Build.objects.get(pk=self.config['__config']).config
        return self.config

    def save(self, *args, **kwargs):  # noqa
        """
        Save object.

        To save space on the db we only save the config if it's different
        from the previous one.

        If the config is the same, we save the pk of the object
        that has the **real** config under the ``__config`` key.
        """
        previous = self.previous
        if previous is not None and self.config == previous.get_config():
            previous_pk = previous.pk
            if '__config' in previous.config:
                previous_pk = previous.config['__config']
            self.config = {'__config': previous_pk}
        super(Build, self).save(*args, **kwargs)

    def __str__(self):
        return ugettext(
            'Build {project} for {usernames} ({pk})'.format(
                project=self.project,
                usernames=' '.join(
                    self.project.users.all().values_list('username', flat=True),
                ),
                pk=self.pk,
            ))

    @models.permalink
    def get_absolute_url(self):
        return ('builds_detail', [self.project.slug, self.pk])

    @property
    def finished(self):
        """Return if build has a finished state."""
        return self.state == BUILD_STATE_FINISHED


class BuildCommandResultMixin(object):

    """
    Mixin for common command result methods/properties.

    Shared methods between the database model :py:class:`BuildCommandResult` and
    non-model respresentations of build command results from the API
    """

    @property
    def successful(self):
        """Did the command exit with a successful exit code."""
        return self.exit_code == 0

    @property
    def failed(self):
        """
        Did the command exit with a failing exit code.

        Helper for inverse of :py:meth:`successful`
        """
        return not self.successful


@python_2_unicode_compatible
class BuildCommandResult(BuildCommandResultMixin, models.Model):

    """Build command for a ``Build``."""

    build = models.ForeignKey(
        Build, verbose_name=_('Build'), related_name='commands')

    command = models.TextField(_('Command'))
    description = models.TextField(_('Description'), blank=True)
    output = models.TextField(_('Command output'), blank=True)
    exit_code = models.IntegerField(_('Command exit code'))

    start_time = models.DateTimeField(_('Start time'))
    end_time = models.DateTimeField(_('End time'))

    class Meta(object):
        ordering = ['start_time']
        get_latest_by = 'start_time'

    objects = RelatedBuildQuerySet.as_manager()

    def __str__(self):
        return (
            ugettext('Build command {pk} for build {build}')
            .format(pk=self.pk, build=self.build))

    @property
    def run_time(self):
        """Total command runtime in seconds."""
        if self.start_time is not None and self.end_time is not None:
            diff = self.end_time - self.start_time
            return diff.seconds