quay/data/registry_model/registry_oci_model.py

# pylint: disable=protected-access
import logging

from contextlib import contextmanager

from data import database
from data import model
from data.model import oci, DataModelException
from data.model.oci.retriever import RepositoryContentRetriever
from data.database import db_transaction, Image
from data.registry_model.interface import RegistryDataInterface
from data.registry_model.datatypes import Tag, Manifest, LegacyImage, Label, SecurityScanStatus
from data.registry_model.shared import SharedModel
from data.registry_model.label_handlers import apply_label_to_manifest
from image.docker import ManifestException
from image.docker.schema2 import DOCKER_SCHEMA2_MANIFESTLIST_CONTENT_TYPE


logger = logging.getLogger(__name__)


class OCIModel(SharedModel, RegistryDataInterface):
  """
  OCIModel implements the data model for the registry API using a database schema
  after it was changed to support the OCI specification.
  """
  def supports_schema2(self, namespace_name):
    """ Returns whether the implementation of the data interface supports schema 2 format
        manifests. """
    return True

  def get_legacy_tags_map(self, repository_ref, storage):
    """ Returns a map from tag name to its legacy image ID, for all tags with legacy images in
        the repository. Note that this can be a *very* heavy operation.
    """
    tags = oci.tag.list_alive_tags(repository_ref._db_id)
    legacy_images_map = oci.tag.get_legacy_images_for_tags(tags)

    tags_map = {}
    for tag in tags:
      legacy_image = legacy_images_map.get(tag.id)
      if legacy_image is not None:
        tags_map[tag.name] = legacy_image.docker_image_id
      else:
        manifest = Manifest.for_manifest(tag.manifest, None)
        if legacy_image is None and manifest.media_type == DOCKER_SCHEMA2_MANIFESTLIST_CONTENT_TYPE:
          # See if we can lookup a schema1 legacy image.
          v1_compatible = self.get_schema1_parsed_manifest(manifest, '', '', '', storage)
          if v1_compatible is not None:
            v1_id = v1_compatible.leaf_layer_v1_image_id
            if v1_id is not None:
              tags_map[tag.name] = v1_id


    return tags_map

  def _get_legacy_compatible_image_for_manifest(self, manifest, storage):
    # Check for a legacy image directly on the manifest.
    if manifest.media_type != DOCKER_SCHEMA2_MANIFESTLIST_CONTENT_TYPE:
      return oci.shared.get_legacy_image_for_manifest(manifest._db_id)
    
    # Otherwise, lookup a legacy image associated with the v1-compatible manifest
    # in the list.
    try:
      manifest_obj = database.Manifest.get(id=manifest._db_id)
    except database.Manifest.DoesNotExist:
      logger.exception('Could not find manifest for manifest `%s`', manifest._db_id)
      return None

    # See if we can lookup a schema1 legacy image.
    v1_compatible = self.get_schema1_parsed_manifest(manifest, '', '', '', storage)
    if v1_compatible is None:
      return None

    v1_id = v1_compatible.leaf_layer_v1_image_id
    if v1_id is None:
      return None

    return model.image.get_image(manifest_obj.repository_id, v1_id)

  def find_matching_tag(self, repository_ref, tag_names):
    """ Finds an alive tag in the repository matching one of the given tag names and returns it
        or None if none.
    """
    found_tag = oci.tag.find_matching_tag(repository_ref._db_id, tag_names)
    assert found_tag is None or not found_tag.hidden
    return Tag.for_tag(found_tag)

  def get_most_recent_tag(self, repository_ref):
    """ Returns the most recently pushed alive tag in the repository, if any. If none, returns
        None.
    """
    found_tag = oci.tag.get_most_recent_tag(repository_ref._db_id)
    assert found_tag is None or not found_tag.hidden
    return Tag.for_tag(found_tag)

  def get_manifest_for_tag(self, tag, backfill_if_necessary=False):
    """ Returns the manifest associated with the given tag. """
    legacy_image = oci.shared.get_legacy_image_for_manifest(tag._manifest)
    return Manifest.for_manifest(tag._manifest, LegacyImage.for_image(legacy_image))

  def lookup_manifest_by_digest(self, repository_ref, manifest_digest, allow_dead=False,
                                include_legacy_image=False):
    """ Looks up the manifest with the given digest under the given repository and returns it
        or None if none. """
    manifest = oci.manifest.lookup_manifest(repository_ref._db_id, manifest_digest,
                                            allow_dead=allow_dead)
    if manifest is None:
      return None

    legacy_image = None
    if include_legacy_image:
      try:
        legacy_image_id = database.ManifestLegacyImage.get(manifest=manifest).image.docker_image_id
        legacy_image = self.get_legacy_image(repository_ref, legacy_image_id, include_parents=True)
      except database.ManifestLegacyImage.DoesNotExist:
        return None

    return Manifest.for_manifest(manifest, legacy_image)

  def create_manifest_label(self, manifest, key, value, source_type_name, media_type_name=None):
    """ Creates a label on the manifest with the given key and value. """
    label_data = dict(key=key, value=value, source_type_name=source_type_name,
                      media_type_name=media_type_name)

    with db_transaction():
      # Create the label itself.
      label = oci.label.create_manifest_label(manifest._db_id, key, value, source_type_name,
                                              media_type_name)
      if label is None:
        return None

      # Apply any changes to the manifest that the label prescribes.
      apply_label_to_manifest(label_data, manifest, self)

    return Label.for_label(label)

  @contextmanager
  def batch_create_manifest_labels(self, manifest):
    """ Returns a context manager for batch creation of labels on a manifest.

        Can raise InvalidLabelKeyException or InvalidMediaTypeException depending
        on the validation errors.
    """
    labels_to_add = []
    def add_label(key, value, source_type_name, media_type_name=None):
      labels_to_add.append(dict(key=key, value=value, source_type_name=source_type_name,
                                media_type_name=media_type_name))

    yield add_label

    # TODO: make this truly batch once we've fully transitioned to V2_2 and no longer need
    # the mapping tables.
    for label_data in labels_to_add:
      with db_transaction():
        # Create the label itself.
        oci.label.create_manifest_label(manifest._db_id, **label_data)

        # Apply any changes to the manifest that the label prescribes.
        apply_label_to_manifest(label_data, manifest, self)

  def list_manifest_labels(self, manifest, key_prefix=None):
    """ Returns all labels found on the manifest. If specified, the key_prefix will filter the
        labels returned to those keys that start with the given prefix.
    """
    labels = oci.label.list_manifest_labels(manifest._db_id, prefix_filter=key_prefix)
    return [Label.for_label(l) for l in labels]

  def get_manifest_label(self, manifest, label_uuid):
    """ Returns the label with the specified UUID on the manifest or None if none. """
    return Label.for_label(oci.label.get_manifest_label(label_uuid, manifest._db_id))

  def delete_manifest_label(self, manifest, label_uuid):
    """ Delete the label with the specified UUID on the manifest. Returns the label deleted
        or None if none.
    """
    return Label.for_label(oci.label.delete_manifest_label(label_uuid, manifest._db_id))

  def list_repository_tags(self, repository_ref, include_legacy_images=False,
                           start_pagination_id=None,
                           limit=None):
    """
    Returns a list of all the active tags in the repository. Note that this can be a *heavy*
    operation on repositories with a lot of tags, and should be avoided for more targetted
    operations wherever possible.
    """
    tags = list(oci.tag.list_alive_tags(repository_ref._db_id, start_pagination_id, limit))
    legacy_images_map = {}
    if include_legacy_images:
      legacy_images_map = oci.tag.get_legacy_images_for_tags(tags)

    return [Tag.for_tag(tag, legacy_image=LegacyImage.for_image(legacy_images_map.get(tag.id)))
            for tag in tags]

  def list_repository_tag_history(self, repository_ref, page=1, size=100, specific_tag_name=None,
                                  active_tags_only=False):
    """
    Returns the history of all tags in the repository (unless filtered). This includes tags that
    have been made in-active due to newer versions of those tags coming into service.
    """
    tags, has_more = oci.tag.list_repository_tag_history(repository_ref._db_id,
                                                         page, size,
                                                         specific_tag_name,
                                                         active_tags_only)

    # TODO: do we need legacy images here?
    legacy_images_map = oci.tag.get_legacy_images_for_tags(tags)
    return [Tag.for_tag(tag, LegacyImage.for_image(legacy_images_map.get(tag.id))) for tag in tags], has_more

  def has_expired_tag(self, repository_ref, tag_name):
    """
    Returns true if and only if the repository contains a tag with the given name that is expired.
    """
    return bool(oci.tag.get_expired_tag(repository_ref._db_id, tag_name))

  def get_repo_tag(self, repository_ref, tag_name, include_legacy_image=False):
    """
    Returns the latest, *active* tag found in the repository, with the matching name
    or None if none.
    """
    assert isinstance(tag_name, basestring)

    tag = oci.tag.get_tag(repository_ref._db_id, tag_name)
    if tag is None:
      return None

    legacy_image = None
    if include_legacy_image:
      legacy_images = oci.tag.get_legacy_images_for_tags([tag])
      legacy_image = legacy_images.get(tag.id)

    return Tag.for_tag(tag, legacy_image=LegacyImage.for_image(legacy_image))

  def create_manifest_and_retarget_tag(self, repository_ref, manifest_interface_instance, tag_name,
                                       storage):
    """ Creates a manifest in a repository, adding all of the necessary data in the model.

        The `manifest_interface_instance` parameter must be an instance of the manifest
        interface as returned by the image/docker package.

        Note that all blobs referenced by the manifest must exist under the repository or this
        method will fail and return None.

        Returns a reference to the (created manifest, tag) or (None, None) on error.
    """
    # Get or create the manifest itself.
    created_manifest = oci.manifest.get_or_create_manifest(repository_ref._db_id,
                                                           manifest_interface_instance,
                                                           storage)
    if created_manifest is None:
      return (None, None)

    # Re-target the tag to it.
    tag = oci.tag.retarget_tag(tag_name, created_manifest.manifest)
    if tag is None:
      return (None, None)

    legacy_image = oci.shared.get_legacy_image_for_manifest(created_manifest.manifest)
    li = LegacyImage.for_image(legacy_image)
    wrapped_manifest = Manifest.for_manifest(created_manifest.manifest, li)

    # Apply any labels that should modify the created tag.
    if created_manifest.labels_to_apply:
      for key, value in created_manifest.labels_to_apply.iteritems():
        apply_label_to_manifest(dict(key=key, value=value), wrapped_manifest, self)

      # Reload the tag in case any updates were applied.
      tag = database.Tag.get(id=tag.id)

    return (wrapped_manifest, Tag.for_tag(tag, li))

  def retarget_tag(self, repository_ref, tag_name, manifest_or_legacy_image, storage,
                   is_reversion=False):
    """
    Creates, updates or moves a tag to a new entry in history, pointing to the manifest or
    legacy image specified. If is_reversion is set to True, this operation is considered a
    reversion over a previous tag move operation. Returns the updated Tag or None on error.
    """
    manifest_id = manifest_or_legacy_image._db_id
    if isinstance(manifest_or_legacy_image, LegacyImage):
      # If a legacy image was required, build a new manifest for it and move the tag to that.
      try:
        image_row = database.Image.get(id=manifest_or_legacy_image._db_id)
      except database.Image.DoesNotExist:
        return None

      manifest_instance = self._build_manifest_for_legacy_image(tag_name, image_row)
      if manifest_instance is None:
        return None

      created = oci.manifest.get_or_create_manifest(repository_ref._db_id, manifest_instance,
                                                    storage)
      if created is None:
        return None

      manifest_id = created.manifest.id

    tag = oci.tag.retarget_tag(tag_name, manifest_id, is_reversion=is_reversion)
    legacy_image = LegacyImage.for_image(oci.shared.get_legacy_image_for_manifest(manifest_id))
    return Tag.for_tag(tag, legacy_image)

  def delete_tag(self, repository_ref, tag_name):
    """
    Deletes the latest, *active* tag with the given name in the repository.
    """
    deleted_tag = oci.tag.delete_tag(repository_ref._db_id, tag_name)
    if deleted_tag is None:
      # TODO(jschorr): This is only needed because preoci raises an exception. Remove and fix
      # expected status codes once PreOCIModel is gone.
      msg = ('Invalid repository tag \'%s\' on repository' % tag_name)
      raise DataModelException(msg)

    return Tag.for_tag(deleted_tag)

  def delete_tags_for_manifest(self, manifest):
    """
    Deletes all tags pointing to the given manifest, making the manifest inaccessible for pulling.
    Returns the tags deleted, if any. Returns None on error.
    """
    deleted_tags = oci.tag.delete_tags_for_manifest(manifest._db_id)
    return [Tag.for_tag(tag) for tag in deleted_tags]

  def change_repository_tag_expiration(self, tag, expiration_date):
    """ Sets the expiration date of the tag under the matching repository to that given. If the
        expiration date is None, then the tag will not expire. Returns a tuple of the previous
        expiration timestamp in seconds (if any), and whether the operation succeeded.
    """
    return oci.tag.change_tag_expiration(tag._db_id, expiration_date)

  def get_legacy_images_owned_by_tag(self, tag):
    """ Returns all legacy images *solely owned and used* by the given tag. """
    tag_obj = oci.tag.get_tag_by_id(tag._db_id)
    if tag_obj is None:
      return None

    tags = oci.tag.list_alive_tags(tag_obj.repository_id)
    legacy_images = oci.tag.get_legacy_images_for_tags(tags)

    tag_legacy_image = legacy_images.get(tag._db_id)
    if tag_legacy_image is None:
      return None

    assert isinstance(tag_legacy_image, Image)

    # Collect the IDs of all images that the tag uses.
    tag_image_ids = set()
    tag_image_ids.add(tag_legacy_image.id)
    tag_image_ids.update(tag_legacy_image.ancestor_id_list())

    # Remove any images shared by other tags.
    for current in tags:
      if current == tag_obj:
        continue

      current_image = legacy_images.get(current.id)
      if current_image is None:
        continue

      tag_image_ids.discard(current_image.id)
      tag_image_ids = tag_image_ids.difference(current_image.ancestor_id_list())
      if not tag_image_ids:
        return []

    if not tag_image_ids:
      return []

    # Load the images we need to return.
    images = database.Image.select().where(database.Image.id << list(tag_image_ids))
    all_image_ids = set()
    for image in images:
      all_image_ids.add(image.id)
      all_image_ids.update(image.ancestor_id_list())

    # Build a map of all the images and their parents.
    images_map = {}
    all_images = database.Image.select().where(database.Image.id << list(all_image_ids))
    for image in all_images:
      images_map[image.id] = image

    return [LegacyImage.for_image(image, images_map=images_map) for image in images]

  def get_security_status(self, manifest_or_legacy_image):
    """ Returns the security status for the given manifest or legacy image or None if none. """
    image = None

    if isinstance(manifest_or_legacy_image, Manifest):
      image = oci.shared.get_legacy_image_for_manifest(manifest_or_legacy_image._db_id)
      if image is None:
        return SecurityScanStatus.UNSUPPORTED
    else:
      try:
        image = database.Image.get(id=manifest_or_legacy_image._db_id)
      except database.Image.DoesNotExist:
        return None

    if image.security_indexed_engine is not None and image.security_indexed_engine >= 0:
      return SecurityScanStatus.SCANNED if image.security_indexed else SecurityScanStatus.FAILED

    return SecurityScanStatus.QUEUED

  def backfill_manifest_for_tag(self, tag):
    """ Backfills a manifest for the V1 tag specified.
        If a manifest already exists for the tag, returns that manifest.

        NOTE: This method will only be necessary until we've completed the backfill, at which point
        it should be removed.
    """
    # Nothing to do for OCI tags.
    manifest = tag.manifest
    if manifest is None:
      return None

    legacy_image = oci.shared.get_legacy_image_for_manifest(manifest)
    return Manifest.for_manifest(manifest, LegacyImage.for_image(legacy_image))

  def list_manifest_layers(self, manifest, include_placements=False):
    """ Returns an *ordered list* of the layers found in the manifest, starting at the base and
        working towards the leaf, including the associated Blob and its placements (if specified).
        Returns None if the manifest could not be parsed and validated.
    """
    try:
      manifest_obj = database.Manifest.get(id=manifest._db_id)
    except database.Manifest.DoesNotExist:
      logger.exception('Could not find manifest for manifest `%s`', manifest._db_id)
      return None

    try:
      parsed = manifest.get_parsed_manifest()
    except ManifestException:
      logger.exception('Could not parse and validate manifest `%s`', manifest._db_id)
      return None

    return self._list_manifest_layers(manifest_obj.repository_id, parsed, include_placements)

  def lookup_derived_image(self, manifest, verb, varying_metadata=None, include_placements=False):
    """
    Looks up the derived image for the given manifest, verb and optional varying metadata and
    returns it or None if none.
    """
    legacy_image = oci.shared.get_legacy_image_for_manifest(manifest._db_id)
    if legacy_image is None:
      return None

    derived = model.image.find_derived_storage_for_image(legacy_image, verb, varying_metadata)
    return self._build_derived(derived, verb, varying_metadata, include_placements)

  def lookup_or_create_derived_image(self, manifest, verb, storage_location, storage,
                                    varying_metadata=None,
                                     include_placements=False):
    """
    Looks up the derived image for the given maniest, verb and optional varying metadata
    and returns it. If none exists, a new derived image is created.
    """
    legacy_image = self._get_legacy_compatible_image_for_manifest(manifest, storage)
    if legacy_image is None:
      return None

    derived = model.image.find_or_create_derived_storage(legacy_image, verb, storage_location,
                                                         varying_metadata)
    return self._build_derived(derived, verb, varying_metadata, include_placements)

  def set_tags_expiration_for_manifest(self, manifest, expiration_sec):
    """
    Sets the expiration on all tags that point to the given manifest to that specified.
    """
    oci.tag.set_tag_expiration_sec_for_manifest(manifest._db_id, expiration_sec)

  def get_schema1_parsed_manifest(self, manifest, namespace_name, repo_name, tag_name, storage):
    """ Returns the schema 1 manifest for this manifest, or None if none. """
    try:
      parsed = manifest.get_parsed_manifest()
    except ManifestException:
      return None

    try:
      manifest_row = database.Manifest.get(id=manifest._db_id)
    except database.Manifest.DoesNotExist:
      return None

    retriever = RepositoryContentRetriever(manifest_row.repository_id, storage)
    return parsed.get_v1_compatible_manifest(namespace_name, repo_name, tag_name, retriever)

  def create_manifest_with_temp_tag(self, repository_ref, manifest_interface_instance,
                                    expiration_sec, storage):
    """ Creates a manifest under the repository and sets a temporary tag to point to it.
        Returns the manifest object created or None on error.
    """
    # Get or create the manifest itself.
    created_manifest = oci.manifest.get_or_create_manifest(repository_ref._db_id,
                                                           manifest_interface_instance,
                                                           storage)
    if created_manifest is None:
      return None

    # Point a temporary tag to the manifest.
    tag = oci.tag.create_temporary_tag(created_manifest.manifest, expiration_sec)
    if tag is None:
      return None

    legacy_image = oci.shared.get_legacy_image_for_manifest(created_manifest.manifest)
    li = LegacyImage.for_image(legacy_image)
    return Manifest.for_manifest(created_manifest.manifest, li)


oci_model = OCIModel()