#!/usr/bin/env python
"""Tests for the FileFinder flow."""

import glob
import hashlib
import io
import os
import shutil
import stat
import struct
import time
from typing import Any, List, Optional, Sequence
from unittest import mock

from absl import app

from grr_response_client import vfs
from grr_response_client.client_actions.file_finder_utils import uploading
from grr_response_core.lib import rdfvalue
from grr_response_core.lib.rdfvalues import client as rdf_client
from grr_response_core.lib.rdfvalues import client_fs as rdf_client_fs
from grr_response_core.lib.rdfvalues import file_finder as rdf_file_finder
from grr_response_core.lib.rdfvalues import paths as rdf_paths
from grr_response_core.lib.util import temp
from grr_response_proto import flows_pb2
from grr_response_proto import objects_pb2
from grr_response_server import data_store
from grr_response_server import file_store
from grr_response_server.databases import db
from grr_response_server.databases import db_test_utils
from grr_response_server.flows.general import file_finder
from grr_response_server.flows.general import transfer
from grr_response_server.rdfvalues import mig_objects
from grr_response_server.rdfvalues import objects as rdf_objects
from grr.test_lib import action_mocks
from grr.test_lib import filesystem_test_lib
from grr.test_lib import flow_test_lib
from grr.test_lib import test_lib
from grr.test_lib import vfs_test_lib

# pylint:mode=test


class TestFileFinderFlow(vfs_test_lib.VfsTestCase,
                         flow_test_lib.FlowTestsBaseclass):
  """Test the FileFinder flow."""

  def FileNameToURN(self, fname):
    return rdfvalue.RDFURN(self.client_id).Add("/fs/os").Add(
        os.path.join(self.base_path, "searching", fname))

  def FilenameToPathComponents(self, fname):
    path = os.path.join(self.base_path, "searching", fname).lstrip("/")
    return tuple(path.split(os.path.sep))

  EXPECTED_SHA256_HASHES = {
      "auth.log": (
          "91c8d6287a095a6fa6437dac50ffe3fe5c5e0d06dff3ae830eedfce515ad6451"
      ),
      "dpkg.log": (
          "48303a1e7ceec679f6d417b819f42779575ffe8eabf9c880d286a1ee074d8145"
      ),
      "dpkg_false.log": (
          "a35aface4b45e3f1a95b0df24efc50e14fbedcaa6a750ba32358eaaffe3c4fb0"
      ),
  }

  def CheckFilesHashed(self, fnames):
    """Checks the returned hashes."""

    for fname in fnames:
      try:
        file_hash = self.EXPECTED_SHA256_HASHES[fname]
      except KeyError:
        raise RuntimeError("Can't check unexpected result for correct "
                           "hashes: %s" % fname)

      proto_path_info = data_store.REL_DB.ReadPathInfo(
          self.client_id,
          rdf_objects.PathInfo.PathType.OS,
          components=self.FilenameToPathComponents(fname),
      )
      path_info = mig_objects.ToRDFPathInfo(proto_path_info)
      hash_obj = path_info.hash_entry

      self.assertEqual(str(hash_obj.sha256), file_hash)

  def CheckFilesNotHashed(self, fnames):
    for fname in fnames:
      try:
        path_info = data_store.REL_DB.ReadPathInfo(
            self.client_id,
            rdf_objects.PathInfo.PathType.OS,
            components=self.FilenameToPathComponents(fname))
        self.assertFalse(path_info.HasField("hash_entry"))
      except db.UnknownPathError:
        pass  # No path at all, everything is okay.

  def CheckFilesDownloaded(self, fnames):
    for fname in fnames:
      path_info = data_store.REL_DB.ReadPathInfo(
          self.client_id,
          rdf_objects.PathInfo.PathType.OS,
          components=self.FilenameToPathComponents(fname))
      size = path_info.stat_entry.st_size

      filepath = os.path.join(self.base_path, "searching", fname)
      with io.open(filepath, mode="rb") as fd:
        test_data = fd.read()

      self.assertEqual(size, len(test_data))

      fd = file_store.OpenFile(
          db.ClientPath(
              self.client_id,
              rdf_objects.PathInfo.PathType.OS,
              components=self.FilenameToPathComponents(fname)))

      # Make sure we can actually read the file.
      self.assertEqual(fd.read(), test_data)

  def CheckFilesNotDownloaded(self, fnames):
    for fname in fnames:
      try:
        file_store.OpenFile(
            db.ClientPath(
                self.client_id,
                rdf_objects.PathInfo.PathType.OS,
                components=self.FilenameToPathComponents(fname)))
        self.fail("Found downloaded file: %s" % fname)
      except (file_store.FileHasNoContentError, file_store.FileNotFoundError):
        pass

  def CheckFiles(self, expected_fnames, skipped_fnames, results):
    if expected_fnames is None:
      self.assertFalse(results)
      return

    # If results are expected, check that they are present in the results.
    # Also check that there are no other files.
    self.assertLen(results, len(set(expected_fnames + skipped_fnames)))

    for r in results:
      self.assertIsInstance(r, rdf_file_finder.FileFinderResult)

    self.assertCountEqual(
        [os.path.basename(r.stat_entry.pathspec.path) for r in results],
        expected_fnames + skipped_fnames,
    )

  def CheckReplies(self, replies, action, expected_files, skipped_files):
    reply_count = 0
    for reply in replies:
      self.assertIsInstance(reply, rdf_file_finder.FileFinderResult)

      is_skipped = reply.stat_entry.pathspec.Basename() in skipped_files

      reply_count += 1
      if action == rdf_file_finder.FileFinderAction.Action.STAT:
        self.assertTrue(reply.stat_entry)
        self.assertFalse(reply.hash_entry)
      elif action == rdf_file_finder.FileFinderAction.Action.DOWNLOAD:
        self.assertTrue(reply.stat_entry)
        if not is_skipped:
          self.assertTrue(reply.hash_entry)
      elif action == rdf_file_finder.FileFinderAction.Action.HASH:
        self.assertTrue(reply.stat_entry)
        if not is_skipped:
          self.assertTrue(reply.hash_entry)

      if (
          action != rdf_file_finder.FileFinderAction.Action.STAT
          and not is_skipped
      ):
        # Check that file's hash is correct.
        file_basename = reply.stat_entry.pathspec.Basename()
        try:
          file_hash = self.EXPECTED_SHA256_HASHES[file_basename]
        except KeyError:
          raise RuntimeError("Can't check unexpected result for correct "
                             "hashes: %s" % file_basename)

        self.assertEqual(str(reply.hash_entry.sha256), file_hash)

    # Skipped files are reported, but not collected/hashed (i.e. the action is
    # skipped).
    self.assertEqual(reply_count, len(expected_files) + len(skipped_files))

  def RunFlow(
      self,
      paths: Optional[List[str]] = None,
      conditions: Optional[List[rdf_file_finder.FileFinderCondition]] = None,
      action: Optional[rdf_file_finder.FileFinderAction] = None,
  ) -> Sequence[Any]:
    self.last_session_id = flow_test_lib.TestFlowHelper(
        file_finder.FileFinder.__name__,
        self.client_mock,
        client_id=self.client_id,
        paths=paths or [self.path],
        pathtype=rdf_paths.PathSpec.PathType.OS,
        action=action,
        conditions=conditions,
        creator=self.test_username,
    )
    return flow_test_lib.GetFlowResults(self.client_id, self.last_session_id)

  def RunFlowAndCheckResults(
      self,
      conditions=None,
      action=rdf_file_finder.FileFinderAction.Action.STAT,
      expected_files=None,
      non_expected_files=None,
      skipped_files=None,
      paths=None,
  ):
    if not isinstance(action, rdf_file_finder.FileFinderAction):
      action = rdf_file_finder.FileFinderAction(action_type=action)
    action_type = action.action_type

    conditions = conditions or []
    expected_files = expected_files or []
    non_expected_files = non_expected_files or []
    skipped_files = skipped_files or []

    results = self.RunFlow(paths=paths, conditions=conditions, action=action)
    self.CheckReplies(results, action_type, expected_files, skipped_files)

    self.CheckFiles(expected_files, skipped_files, results)

    if action_type == rdf_file_finder.FileFinderAction.Action.STAT:
      self.CheckFilesNotDownloaded(
          expected_files + non_expected_files + skipped_files
      )
      self.CheckFilesNotHashed(
          expected_files + non_expected_files + skipped_files
      )
    elif action_type == rdf_file_finder.FileFinderAction.Action.DOWNLOAD:
      self.CheckFilesHashed(expected_files)
      self.CheckFilesNotHashed(non_expected_files + skipped_files)
      self.CheckFilesDownloaded(expected_files)
      self.CheckFilesNotDownloaded(non_expected_files + skipped_files)
      # Downloaded files are hashed to allow for deduping.
    elif action_type == rdf_file_finder.FileFinderAction.Action.HASH:
      self.CheckFilesNotDownloaded(
          expected_files + non_expected_files + skipped_files
      )
      self.CheckFilesHashed(expected_files)
      self.CheckFilesNotHashed(non_expected_files + skipped_files)
    return results

  def setUp(self):
    super().setUp()
    self.client_mock = action_mocks.ClientFileFinderClientMock()

    self.fixture_path = os.path.join(self.base_path, "searching")
    self.path = os.path.join(self.fixture_path, "*.log")
    self.client_id = self.SetupClient(0)
    vfs.Init()

  def testFileFinderStatActionWithoutConditions(self):
    self.RunFlowAndCheckResults(
        action=rdf_file_finder.FileFinderAction.Action.STAT,
        expected_files=["auth.log", "dpkg.log", "dpkg_false.log"])

  def testCollectingSingleFileCreatesNecessaryPathInfos(self):
    path = os.path.join(self.fixture_path, "auth.log")
    self.RunFlowAndCheckResults(
        action=rdf_file_finder.FileFinderAction.Action.DOWNLOAD,
        paths=[path],
        expected_files=[os.path.basename(path)])

    # If the call below doesn't raise, then we have a correct entry in the DB.
    data_store.REL_DB.ReadPathInfo(
        self.client_id, rdf_objects.PathInfo.PathType.OS,
        tuple(path.strip(os.path.sep).split(os.path.sep)))

  def testFileFinderStat(self):
    files_to_check = [
        # Some files.
        "VFSFixture/etc/netgroup",
        "osx_fsdata",
        # Matches lsb-release, lsb-release-bad, lsb-release-notubuntu
        "parser_test/lsb-release*",
        # Some directories.
        "a",
        "profiles"
    ]

    paths = [os.path.join(self.base_path, name) for name in files_to_check]
    expected_paths = []
    for name in paths:
      for result in glob.glob(name):
        expected_paths.append(result)

    # There was a bug in FileFinder with files/directories in the root dir.
    paths.append("/bin")
    expected_paths.append("/bin")

    # Make sure all the files still exist.
    self.assertLen(expected_paths, 8)

    results = self.RunFlow(
        action=rdf_file_finder.FileFinderAction(
            action_type=rdf_file_finder.FileFinderAction.Action.STAT),
        paths=paths)

    result_paths = [r.stat_entry.pathspec.path for r in results]

    self.assertCountEqual(expected_paths, result_paths)

  FS_NODUMP_FL = 0x00000040
  FS_UNRM_FL = 0x00000002

  def testFileFinderStatExtFlags(self):
    with temp.AutoTempFilePath() as temp_filepath:
      filesystem_test_lib.Chattr(temp_filepath, attrs=["+d"])

      action = rdf_file_finder.FileFinderAction.Stat()
      results = self.RunFlow(action=action, paths=[temp_filepath])
      self.assertLen(results, 1)

      stat_entry = results[0].stat_entry
      self.assertTrue(stat_entry.st_flags_linux & self.FS_NODUMP_FL)
      self.assertFalse(stat_entry.st_flags_linux & self.FS_UNRM_FL)

  def testFileFinderStatExtAttrs(self):
    with temp.AutoTempFilePath() as temp_filepath:
      filesystem_test_lib.SetExtAttr(
          temp_filepath, name=b"user.bar", value=b"quux")
      filesystem_test_lib.SetExtAttr(
          temp_filepath, name=b"user.baz", value=b"norf")

      action = rdf_file_finder.FileFinderAction.Stat(collect_ext_attrs=True)
      results = self.RunFlow(action=action, paths=[temp_filepath])
      self.assertLen(results, 1)

      stat_entry = results[0].stat_entry
      self.assertCountEqual(stat_entry.ext_attrs, [
          rdf_client_fs.ExtAttr(name=b"user.bar", value=b"quux"),
          rdf_client_fs.ExtAttr(name=b"user.baz", value=b"norf"),
      ])

  def testFileFinderDownloadActionWithMultiplePathsAndFilesInFilestore(self):
    # Do a first run to put all files into the file store.
    self.RunFlowAndCheckResults(
        action=rdf_file_finder.FileFinderAction.Action.DOWNLOAD,
        expected_files=["auth.log", "dpkg.log", "dpkg_false.log"])

    # This will get the file contents from the filestore instead of collecting
    # them.
    self.RunFlowAndCheckResults(
        action=rdf_file_finder.FileFinderAction.Action.DOWNLOAD,
        expected_files=["auth.log", "dpkg.log", "dpkg_false.log"])

  def testFileFinderDownloadActionWithoutConditions(self):
    self.RunFlowAndCheckResults(
        action=rdf_file_finder.FileFinderAction.Action.DOWNLOAD,
        expected_files=["auth.log", "dpkg.log", "dpkg_false.log"])

  def testFileFinderHashActionWithoutConditions(self):
    self.RunFlowAndCheckResults(
        action=rdf_file_finder.FileFinderAction.Action.HASH,
        expected_files=["auth.log", "dpkg.log", "dpkg_false.log"])

  CONDITION_TESTS_ACTIONS = sorted(
      set(rdf_file_finder.FileFinderAction.Action.enum_dict.values()))

  def testLiteralMatchConditionWithEmptyLiteral(self):
    match = rdf_file_finder.FileFinderContentsLiteralMatchCondition(
        mode=rdf_file_finder.FileFinderContentsLiteralMatchCondition.Mode
        .ALL_HITS,
        bytes_before=10,
        bytes_after=10)  # No `literal=` provided.
    literal_condition = rdf_file_finder.FileFinderCondition(
        condition_type=rdf_file_finder.FileFinderCondition.Type
        .CONTENTS_LITERAL_MATCH,
        contents_literal_match=match)

    for action in self.CONDITION_TESTS_ACTIONS:
      # Flow arguments validation should fail with an empty literal.
      with self.assertRaises(ValueError):
        self.RunFlowAndCheckResults(
            action=action, conditions=[literal_condition])

  def testLiteralMatchConditionWithDifferentActions(self):
    expected_files = ["auth.log"]
    non_expected_files = ["dpkg.log", "dpkg_false.log"]

    match = rdf_file_finder.FileFinderContentsLiteralMatchCondition(
        mode=rdf_file_finder.FileFinderContentsLiteralMatchCondition.Mode
        .ALL_HITS,
        bytes_before=10,
        bytes_after=10,
        literal=b"session opened for user dearjohn")
    literal_condition = rdf_file_finder.FileFinderCondition(
        condition_type=rdf_file_finder.FileFinderCondition.Type
        .CONTENTS_LITERAL_MATCH,
        contents_literal_match=match)

    for action in self.CONDITION_TESTS_ACTIONS:
      results = self.RunFlowAndCheckResults(
          action=action,
          conditions=[literal_condition],
          expected_files=expected_files,
          non_expected_files=non_expected_files)

      # Check that the results' matches fields are correctly filled.
      self.assertLen(results, 1)
      self.assertLen(results[0].matches, 1)
      # The match is at offset 350, but we have bytes_before=10, so the offset
      # of the returned BufferReference is 350-10=340.
      self.assertEqual(results[0].matches[0].offset, 340)
      self.assertEqual(results[0].matches[0].data,
                       b"session): session opened for user dearjohn by (uid=0")

  def testLiteralMatchConditionWithHexEncodedValue(self):
    match = rdf_file_finder.FileFinderContentsLiteralMatchCondition(
        mode=rdf_file_finder.FileFinderContentsLiteralMatchCondition.Mode
        .FIRST_HIT,
        bytes_before=10,
        bytes_after=10,
        literal=b"\x4D\x5A\x90")
    literal_condition = rdf_file_finder.FileFinderCondition(
        condition_type=rdf_file_finder.FileFinderCondition.Type
        .CONTENTS_LITERAL_MATCH,
        contents_literal_match=match)

    paths = [os.path.join(os.path.dirname(self.fixture_path), "win_hello.exe")]

    results = self.RunFlow(paths=paths, conditions=[literal_condition])

    # Check that the results' matches fields are correctly filled. Expecting a
    # match from win_hello.exe
    self.assertLen(results, 1)
    self.assertLen(results[0].matches, 1)
    self.assertEqual(results[0].matches[0].offset, 0)
    self.assertEqual(results[0].matches[0].data,
                     b"MZ\x90\x00\x03\x00\x00\x00\x04\x00\x00\x00\xff")

  def testRegexMatchConditionWithDifferentActions(self):
    expected_files = ["auth.log"]
    non_expected_files = ["dpkg.log", "dpkg_false.log"]

    regex_condition = rdf_file_finder.FileFinderCondition(
        condition_type=(
            rdf_file_finder.FileFinderCondition.Type.CONTENTS_REGEX_MATCH),
        contents_regex_match=(
            rdf_file_finder.FileFinderContentsRegexMatchCondition(
                mode="ALL_HITS",
                bytes_before=10,
                bytes_after=10,
                regex=b"session opened for user .*?john")))

    for action in self.CONDITION_TESTS_ACTIONS:
      results = self.RunFlowAndCheckResults(
          action=action,
          conditions=[regex_condition],
          expected_files=expected_files,
          non_expected_files=non_expected_files)

      self.assertLen(results, 1)
      self.assertLen(results[0].matches, 1)
      # The match is at offset 350, but we have bytes_before=10, so the offset
      # of the returned BufferReference is 350-10=340.
      self.assertEqual(results[0].matches[0].offset, 340)
      self.assertEqual(results[0].matches[0].data,
                       b"session): session opened for user dearjohn by (uid=0")

  def testTwoRegexMatchConditionsWithDifferentActions1(self):
    expected_files = ["auth.log"]
    non_expected_files = ["dpkg.log", "dpkg_false.log"]

    regex_condition1 = rdf_file_finder.FileFinderCondition(
        condition_type=(
            rdf_file_finder.FileFinderCondition.Type.CONTENTS_REGEX_MATCH),
        contents_regex_match=(
            rdf_file_finder.FileFinderContentsRegexMatchCondition(
                mode="ALL_HITS",
                bytes_before=10,
                bytes_after=10,
                regex=b"session opened for user .*?john")))
    regex_condition2 = rdf_file_finder.FileFinderCondition(
        condition_type=(
            rdf_file_finder.FileFinderCondition.Type.CONTENTS_REGEX_MATCH),
        contents_regex_match=(
            rdf_file_finder.FileFinderContentsRegexMatchCondition(
                mode="ALL_HITS",
                bytes_before=10,
                bytes_after=10,
                regex=b"format.*should")))

    for action in self.CONDITION_TESTS_ACTIONS:
      results = self.RunFlowAndCheckResults(
          action=action,
          conditions=[regex_condition1, regex_condition2],
          expected_files=expected_files,
          non_expected_files=non_expected_files)

      self.assertLen(results, 1)
      self.assertLen(results[0].matches, 2)
      # The match is at offset 350, but we have bytes_before=10, so the offset
      # of the returned BufferReference is 350-10=340.
      self.assertEqual(results[0].matches[0].offset, 340)
      self.assertEqual(results[0].matches[0].data,
                       b"session): session opened for user dearjohn by (uid=0")
      # The match is at offset 513, but we have bytes_before=10, so the offset
      # of the returned BufferReference is 513-10=503.
      self.assertEqual(results[0].matches[1].offset, 503)
      self.assertEqual(results[0].matches[1].data,
                       b"rong line format.... should not be he")

  def testTwoRegexMatchConditionsWithDifferentActions2(self):
    expected_files = ["auth.log"]
    non_expected_files = ["dpkg.log", "dpkg_false.log"]

    regex_condition1 = rdf_file_finder.FileFinderCondition(
        condition_type=(
            rdf_file_finder.FileFinderCondition.Type.CONTENTS_REGEX_MATCH),
        contents_regex_match=(
            rdf_file_finder.FileFinderContentsRegexMatchCondition(
                mode="ALL_HITS",
                bytes_before=10,
                bytes_after=10,
                regex=b"session opened for user .*?john")))
    regex_condition2 = rdf_file_finder.FileFinderCondition(
        condition_type=(
            rdf_file_finder.FileFinderCondition.Type.CONTENTS_REGEX_MATCH),
        contents_regex_match=(
            rdf_file_finder.FileFinderContentsRegexMatchCondition(
                mode="FIRST_HIT", bytes_before=10, bytes_after=10,
                regex=b".*")))

    for action in self.CONDITION_TESTS_ACTIONS:
      results = self.RunFlowAndCheckResults(
          action=action,
          conditions=[regex_condition1, regex_condition2],
          expected_files=expected_files,
          non_expected_files=non_expected_files)

      self.assertLen(results, 1)
      self.assertLen(results[0].matches, 2)
      # The match is at offset 350, but we have bytes_before=10, so the offset
      # of the returned BufferReference is 350-10=340.
      self.assertEqual(results[0].matches[0].offset, 340)
      self.assertEqual(results[0].matches[0].data,
                       b"session): session opened for user dearjohn by (uid=0")
      self.assertEqual(results[0].matches[1].offset, 0)
      self.assertEqual(results[0].matches[1].length, 770)

  def testSizeConditionWithDifferentActions(self):
    expected_files = ["dpkg.log", "dpkg_false.log"]
    non_expected_files = ["auth.log"]

    sizes = [
        os.stat(os.path.join(self.fixture_path, f)).st_size
        for f in expected_files
    ]

    size_condition = rdf_file_finder.FileFinderCondition(
        condition_type=rdf_file_finder.FileFinderCondition.Type.SIZE,
        size=rdf_file_finder.FileFinderSizeCondition(
            max_file_size=max(sizes) + 1))

    for action in self.CONDITION_TESTS_ACTIONS:
      self.RunFlowAndCheckResults(
          action=action,
          conditions=[size_condition],
          expected_files=expected_files,
          non_expected_files=non_expected_files)

  def testDownloadAndHashActionSizeLimitWithSkipPolicy(self):
    expected_files = ["dpkg.log", "dpkg_false.log"]
    skipped_files = ["auth.log"]
    sizes = [
        os.stat(os.path.join(self.fixture_path, f)).st_size
        for f in expected_files
    ]

    hash_action = rdf_file_finder.FileFinderAction.Hash(
        max_size=max(sizes) + 1, oversized_file_policy="SKIP")
    download_action = rdf_file_finder.FileFinderAction.Download(
        max_size=max(sizes) + 1, oversized_file_policy="SKIP")

    for action in [hash_action, download_action]:
      self.RunFlowAndCheckResults(
          paths=[self.path],
          action=action,
          expected_files=expected_files,
          skipped_files=skipped_files,
      )

  def testDownloadAndHashActionSizeLimitWithHashTruncatedPolicy(self):
    image_path = os.path.join(self.base_path, "test_img.dd")
    # Read a bit more than a typical chunk (600 * 1024).
    expected_size = 750 * 1024
    with io.open(image_path, "rb") as fd:
      expected_data = fd.read(expected_size)

    d = hashlib.sha1()
    d.update(expected_data)
    expected_hash = d.digest()

    hash_action = rdf_file_finder.FileFinderAction.Hash(
        max_size=expected_size, oversized_file_policy="HASH_TRUNCATED")
    download_action = rdf_file_finder.FileFinderAction.Download(
        max_size=expected_size, oversized_file_policy="HASH_TRUNCATED")

    for action in [hash_action, download_action]:
      self.RunFlow(paths=[image_path], action=action)

      with self.assertRaises(file_store.FileHasNoContentError):
        self._ReadTestFile(["test_img.dd"],
                           path_type=rdf_objects.PathInfo.PathType.OS)

      path_info = self._ReadTestPathInfo(
          ["test_img.dd"], path_type=rdf_objects.PathInfo.PathType.OS)
      self.assertEqual(path_info.hash_entry.sha1, expected_hash)
      self.assertEqual(path_info.hash_entry.num_bytes, expected_size)

  def testDownloadActionSizeLimitWithDownloadTruncatedPolicy(self):
    image_path = os.path.join(self.base_path, "test_img.dd")
    # Read a bit more than a typical chunk (600 * 1024).
    expected_size = 750 * 1024

    action = rdf_file_finder.FileFinderAction.Download(
        max_size=expected_size, oversized_file_policy="DOWNLOAD_TRUNCATED")

    self.RunFlow(paths=[image_path], action=action)
    with io.open(image_path, "rb") as fd:
      expected_data = fd.read(expected_size)

    d = hashlib.sha256()
    d.update(expected_data)
    expected_hash = d.digest()

    data = self._ReadTestFile(["test_img.dd"],
                              path_type=rdf_objects.PathInfo.PathType.OS)
    self.assertEqual(data, expected_data)

    path_info = self._ReadTestPathInfo(
        ["test_img.dd"], path_type=rdf_objects.PathInfo.PathType.OS
    )
    self.assertEqual(path_info.hash_entry.num_bytes, expected_size)
    self.assertEqual(path_info.hash_entry.sha256, expected_hash)

  def testDownloadActionWithMultipleAttemptsWithMultipleSizeLimits(self):
    total_num_chunks = 10
    total_size = (
        total_num_chunks * uploading.TransferStoreUploader.DEFAULT_CHUNK_SIZE
    )

    path = os.path.join(self.temp_dir, "test_big.txt")
    with io.open(path, "wb") as fd:
      for i in range(total_num_chunks):
        fd.write(
            struct.pack("b", i)
            * uploading.TransferStoreUploader.DEFAULT_CHUNK_SIZE
        )

    da = rdf_file_finder.FileFinderDownloadActionOptions

    # Read a truncated version of the file. This tests against a bug in
    # MultiGetFileLogic when first N chunks of the file were already
    # fetched during a previous MultiGetFileLogic run, and as a consequence
    # the file was considered fully fetched, even if the max_file_size value
    # of the current run was much bigger than the size of the previously
    # fetched file.
    action = rdf_file_finder.FileFinderAction.Download(
        max_size=2 * uploading.TransferStoreUploader.DEFAULT_CHUNK_SIZE,
        oversized_file_policy=da.OversizedFilePolicy.DOWNLOAD_TRUNCATED,
    )
    self.RunFlow(paths=[path], action=action)

    action = rdf_file_finder.FileFinderAction.Download(
        max_size=total_size,
        oversized_file_policy=da.OversizedFilePolicy.DOWNLOAD_TRUNCATED)
    self.RunFlow(paths=[path], action=action)

    # Check that the first FileFinder run that downloaded a smaller version
    # of the file, hasn't influenced the next runs.
    pathspec = rdf_paths.PathSpec(
        pathtype=rdf_paths.PathSpec.PathType.OS, path=path)
    client_path = db.ClientPath.FromPathSpec(self.client_id, pathspec)
    fd = file_store.OpenFile(client_path)
    self.assertEqual(fd.size, total_size)

  def testSizeAndRegexConditionsWithDifferentActions(self):
    files_over_size_limit = ["auth.log"]
    filtered_files = ["dpkg.log", "dpkg_false.log"]
    expected_files = []
    non_expected_files = files_over_size_limit + filtered_files

    sizes = [
        os.stat(os.path.join(self.fixture_path, f)).st_size
        for f in files_over_size_limit
    ]

    size_condition = rdf_file_finder.FileFinderCondition(
        condition_type=rdf_file_finder.FileFinderCondition.Type.SIZE,
        size=rdf_file_finder.FileFinderSizeCondition(
            max_file_size=min(sizes) - 1))

    regex_condition = rdf_file_finder.FileFinderCondition(
        condition_type=(
            rdf_file_finder.FileFinderCondition.Type.CONTENTS_REGEX_MATCH),
        contents_regex_match=rdf_file_finder
        .FileFinderContentsRegexMatchCondition(
            mode=(rdf_file_finder.FileFinderContentsRegexMatchCondition.Mode
                  .ALL_HITS),
            bytes_before=10,
            bytes_after=10,
            regex=b"session opened for user .*?john"))

    for action in self.CONDITION_TESTS_ACTIONS:
      self.RunFlowAndCheckResults(
          action=action,
          conditions=[size_condition, regex_condition],
          expected_files=expected_files,
          non_expected_files=non_expected_files)

    # Check that order of conditions doesn't influence results
    for action in self.CONDITION_TESTS_ACTIONS:
      self.RunFlowAndCheckResults(
          action=action,
          conditions=[regex_condition, size_condition],
          expected_files=expected_files,
          non_expected_files=non_expected_files)

  def testModificationTimeConditionWithDifferentActions(self):
    expected_files = ["dpkg.log", "dpkg_false.log"]
    non_expected_files = ["auth.log"]
    change_time = rdfvalue.RDFDatetime.FromSecondsSinceEpoch(1444444440)

    with temp.AutoTempDirPath(remove_non_empty=True) as tempdir:
      os.mkdir(os.path.join(tempdir, "searching"))
      for fname in expected_files + non_expected_files:
        shutil.copyfile(
            os.path.join(self.fixture_path, fname),
            os.path.join(tempdir, "searching", fname),
        )

      # TODO: the complexity of these tests and their reliance on
      # shared state is horrible. All these tests should be rewritten.
      self.base_path = tempdir
      self.fixture_path = os.path.join(self.base_path, "searching")

      os.utime(
          os.path.join(self.fixture_path, "dpkg.log"),
          times=(
              change_time.AsSecondsSinceEpoch() + 1,
              change_time.AsSecondsSinceEpoch() + 1,
          ),
      )
      os.utime(
          os.path.join(self.fixture_path, "dpkg_false.log"),
          times=(
              change_time.AsSecondsSinceEpoch() + 2,
              change_time.AsSecondsSinceEpoch() + 2,
          ),
      )
      os.utime(
          os.path.join(self.fixture_path, "auth.log"),
          times=(
              change_time.AsSecondsSinceEpoch() - 1,
              change_time.AsSecondsSinceEpoch() - 1,
          ),
      )

      modification_time_condition = rdf_file_finder.FileFinderCondition(
          condition_type=rdf_file_finder.FileFinderCondition.Type.MODIFICATION_TIME,
          modification_time=rdf_file_finder.FileFinderModificationTimeCondition(
              min_last_modified_time=change_time
          ),
      )

      for action in self.CONDITION_TESTS_ACTIONS:
        with self.subTest(action):
          self.RunFlowAndCheckResults(
              paths=[os.path.join(self.fixture_path, "*.log")],
              action=action,
              conditions=[modification_time_condition],
              expected_files=expected_files,
              non_expected_files=non_expected_files,
          )

  def testAccessTimeConditionWithDifferentActions(self):
    expected_files = ["dpkg.log", "dpkg_false.log"]
    non_expected_files = ["auth.log"]
    change_time = rdfvalue.RDFDatetime.FromSecondsSinceEpoch(1444444440)

    with temp.AutoTempDirPath(remove_non_empty=True) as tempdir:
      os.mkdir(os.path.join(tempdir, "searching"))
      for fname in expected_files + non_expected_files:
        shutil.copyfile(
            os.path.join(self.fixture_path, fname),
            os.path.join(tempdir, "searching", fname),
        )

      # TODO: the complexity of these tests and their reliance on
      # shared state is horrible. All these tests should be rewritten.
      self.base_path = tempdir
      self.fixture_path = os.path.join(self.base_path, "searching")

      os.utime(
          os.path.join(self.fixture_path, "dpkg.log"),
          times=(
              change_time.AsSecondsSinceEpoch() + 1,
              change_time.AsSecondsSinceEpoch() + 1,
          ),
      )
      os.utime(
          os.path.join(self.fixture_path, "dpkg_false.log"),
          times=(
              change_time.AsSecondsSinceEpoch() + 2,
              change_time.AsSecondsSinceEpoch() + 2,
          ),
      )
      os.utime(
          os.path.join(self.fixture_path, "auth.log"),
          times=(
              change_time.AsSecondsSinceEpoch() - 1,
              change_time.AsSecondsSinceEpoch() - 1,
          ),
      )

      modification_time_condition = rdf_file_finder.FileFinderCondition(
          condition_type=rdf_file_finder.FileFinderCondition.Type.ACCESS_TIME,
          access_time=rdf_file_finder.FileFinderAccessTimeCondition(
              min_last_access_time=change_time
          ),
      )

      for action in self.CONDITION_TESTS_ACTIONS:
        with self.subTest(action):
          self.RunFlowAndCheckResults(
              paths=[os.path.join(self.fixture_path, "*.log")],
              action=action,
              conditions=[modification_time_condition],
              expected_files=expected_files,
              non_expected_files=non_expected_files,
          )

  def testInodeChangeTimeConditionWithDifferentActions(self):
    expected_files = ["dpkg.log", "dpkg_false.log"]
    non_expected_files = ["auth.log"]

    with temp.AutoTempDirPath(remove_non_empty=True) as tempdir:
      os.mkdir(os.path.join(tempdir, "searching"))
      for fname in non_expected_files + expected_files:
        time.sleep(0.1)
        shutil.copyfile(
            os.path.join(self.fixture_path, fname),
            os.path.join(tempdir, "searching", fname),
        )

      # In the loop above auth.log is written first, so if we take a timestamp
      # that's right after its inode change time, it should filter out auth.log,
      # but keep dpkg.log and dpkg_false.log, as they would match the condition.
      auth_log_ctime_ns = int(
          os.stat(os.path.join(tempdir, "searching", "auth.log")).st_ctime_ns
          * 1e-3
      )
      change_time = rdfvalue.RDFDatetime.FromMicrosecondsSinceEpoch(
          auth_log_ctime_ns + 1
      )

      # TODO: the complexity of these tests and their reliance on
      # shared state is horrible. All these tests should be rewritten.
      self.base_path = tempdir
      self.fixture_path = os.path.join(self.base_path, "searching")

      inode_change_time_condition = rdf_file_finder.FileFinderCondition(
          condition_type=rdf_file_finder.FileFinderCondition.Type.INODE_CHANGE_TIME,
          inode_change_time=rdf_file_finder.FileFinderInodeChangeTimeCondition(
              min_last_inode_change_time=change_time
          ),
      )

      for action in self.CONDITION_TESTS_ACTIONS:
        with self.subTest(action):
          self.RunFlowAndCheckResults(
              paths=[os.path.join(self.fixture_path, "*.log")],
              action=action,
              conditions=[inode_change_time_condition],
              expected_files=expected_files,
              non_expected_files=non_expected_files,
          )

  def _RunTSKFileFinder(self, paths):
    image_path = os.path.join(self.base_path, "ntfs_img.dd")
    with mock.patch.object(
        vfs, "_VFS_VIRTUALROOTS", {
            rdf_paths.PathSpec.PathType.TSK:
                rdf_paths.PathSpec(
                    path=image_path, pathtype="OS", offset=63 * 512)
        }):

      action = rdf_file_finder.FileFinderAction.Action.DOWNLOAD
      with test_lib.SuppressLogs():
        flow_test_lib.TestFlowHelper(
            file_finder.FileFinder.__name__,
            client_mock=action_mocks.ClientFileFinderWithVFS(),
            client_id=self.client_id,
            paths=paths,
            pathtype=rdf_paths.PathSpec.PathType.TSK,
            action=rdf_file_finder.FileFinderAction(action_type=action),
            creator=self.test_username,
        )

  def _ListTestChildPathInfos(self,
                              path_components,
                              path_type=rdf_objects.PathInfo.PathType.TSK):
    components = self.base_path.strip("/").split("/")
    components += path_components
    return data_store.REL_DB.ListChildPathInfos(self.client_id, path_type,
                                                tuple(components))

  def _ReadTestPathInfo(self,
                        path_components,
                        path_type=rdf_objects.PathInfo.PathType.TSK):
    components = self.base_path.strip("/").split("/")
    components += path_components
    return mig_objects.ToRDFPathInfo(
        data_store.REL_DB.ReadPathInfo(
            self.client_id, path_type, tuple(components)
        )
    )

  def _ReadTestFile(self,
                    path_components,
                    path_type=rdf_objects.PathInfo.PathType.TSK):
    components = self.base_path.strip("/").split("/")
    components += path_components

    fd = file_store.OpenFile(
        db.ClientPath(self.client_id, path_type, components=tuple(components)))
    return fd.read(10000000)

  def testEmptyPathListDoesNothing(self):
    flow_test_lib.TestFlowHelper(
        file_finder.FileFinder.__name__,
        self.client_mock,
        client_id=self.client_id,
        paths=[],
        pathtype=rdf_paths.PathSpec.PathType.OS,
        creator=self.test_username)

  def testUseExternalStores(self):
    with temp.AutoTempDirPath(remove_non_empty=True) as tempdir:
      path = os.path.join(tempdir, "foo")
      with io.open(path, "w") as fd:
        fd.write("some content")

      paths = [path]
      action = rdf_file_finder.FileFinderAction(
          action_type=rdf_file_finder.FileFinderAction.Action.DOWNLOAD)

      action.download.use_external_stores = False

      with mock.patch.object(file_store.EXTERNAL_FILE_STORE, "AddFiles") as efs:
        flow_id = flow_test_lib.TestFlowHelper(
            file_finder.FileFinder.__name__,
            self.client_mock,
            client_id=self.client_id,
            paths=paths,
            pathtype=rdf_paths.PathSpec.PathType.OS,
            action=action,
            process_non_regular_files=True,
            creator=self.test_username)

      results = flow_test_lib.GetFlowResults(self.client_id, flow_id)

      self.assertLen(results, 1)

      self.assertEqual(efs.call_count, 0)

      # Change the file or the file finder will see that it was downloaded
      # already and skip it.
      with io.open(path, "w") as fd:
        fd.write("some other content")

      action.download.use_external_stores = True

      with mock.patch.object(file_store.EXTERNAL_FILE_STORE, "AddFiles") as efs:
        flow_id = flow_test_lib.TestFlowHelper(
            file_finder.FileFinder.__name__,
            self.client_mock,
            client_id=self.client_id,
            paths=paths,
            pathtype=rdf_paths.PathSpec.PathType.OS,
            action=action,
            process_non_regular_files=True,
            creator=self.test_username)

      results = flow_test_lib.GetFlowResults(self.client_id, flow_id)
      self.assertLen(results, 1)

      self.assertEqual(efs.call_count, 1)

  def testFollowLinks(self):
    with temp.AutoTempDirPath(remove_non_empty=True) as tempdir:
      path = os.path.join(tempdir, "foo")
      lnk_path = os.path.join(tempdir, "foo_lnk")
      path_glob = os.path.join(tempdir, "*")
      with io.open(path, "w") as fd:
        fd.write("some content")

      os.symlink(path, lnk_path)

      results = self.RunFlow(
          action=rdf_file_finder.FileFinderAction.Stat(resolve_links=False),
          paths=[path_glob])

      self.assertLen(results, 2)

      lnk_stats = [
          r.stat_entry
          for r in results
          if stat.S_ISLNK(int(r.stat_entry.st_mode))
      ]
      self.assertNotEmpty(lnk_stats, "No stat entry containing a link found.")

      self.assertNotEqual(results[0].stat_entry.st_ino,
                          results[1].stat_entry.st_ino)

      results = self.RunFlow(
          action=rdf_file_finder.FileFinderAction.Stat(resolve_links=True),
          paths=[path_glob])

      self.assertLen(results, 2)

      lnk_stats = [
          r.stat_entry
          for r in results
          if stat.S_ISLNK(int(r.stat_entry.st_mode))
      ]
      self.assertEmpty(lnk_stats, "Stat entry containing a link found.")

      self.assertEqual(results[0].stat_entry.st_ino,
                       results[1].stat_entry.st_ino)

  def testLinksAndContent(self):
    with temp.AutoTempDirPath(remove_non_empty=True) as tempdir:
      # This sets up a structure as follows:
      # <dir>  tempdir/dir
      # <file> tempdir/foo
      # <lnk>  tempdir/foo_lnk
      # <lnk>  tempdir/dir_lnk

      # foo_lnk is a symbolic link to foo (a file).
      # dir_lnk is a symbolic link to dir (a directory).

      path = os.path.join(tempdir, "foo")
      with io.open(path, "w") as fd:
        fd.write("some content")

      dir_path = os.path.join(tempdir, "dir")
      os.mkdir(dir_path)

      lnk_path = os.path.join(tempdir, "foo_lnk")
      os.symlink(path, lnk_path)

      dir_lnk_path = os.path.join(tempdir, "dir_lnk")
      os.symlink(dir_path, dir_lnk_path)

      path_glob = os.path.join(tempdir, "**3")
      condition = rdf_file_finder.FileFinderCondition.ContentsLiteralMatch(
          literal=b"some")
      results = self.RunFlow(
          action=rdf_file_finder.FileFinderAction.Stat(resolve_links=False),
          conditions=[condition],
          paths=[path_glob])

      self.assertLen(results, 2)

      results = self.RunFlow(
          action=rdf_file_finder.FileFinderAction.Stat(resolve_links=True),
          conditions=[condition],
          paths=[path_glob])

      self.assertLen(results, 2)


class TestClientFileFinderFlow(flow_test_lib.FlowTestsBaseclass):
  """Test the ClientFileFinder flow."""

  def setUp(self):
    super().setUp()
    self.client_id = self.SetupClient(0)

  def _RunCFF(self, paths, action, conditions=None):
    flow_id = flow_test_lib.TestFlowHelper(
        file_finder.ClientFileFinder.__name__,
        action_mocks.ClientFileFinderClientMock(),
        client_id=self.client_id,
        paths=paths,
        pathtype=rdf_paths.PathSpec.PathType.OS,
        action=rdf_file_finder.FileFinderAction(action_type=action),
        conditions=conditions,
        process_non_regular_files=True,
        creator=self.test_username)

    results = flow_test_lib.GetFlowResults(self.client_id, flow_id)
    return results, flow_id

  def testClientFileFinder(self):
    paths = [os.path.join(self.base_path, "{**,.}/*.plist")]
    action = rdf_file_finder.FileFinderAction.Action.STAT
    results, _ = self._RunCFF(paths, action)

    self.assertLen(results, 5)
    relpaths = [
        os.path.relpath(p.stat_entry.pathspec.path, self.base_path)
        for p in results
    ]
    self.assertCountEqual(relpaths, [
        "History.plist", "History.xml.plist", "test.plist",
        "parser_test/com.google.code.grr.plist",
        "parser_test/InstallHistory.plist"
    ])

  @mock.patch.object(
      file_finder.ClientFileFinder, "BLOB_CHECK_DELAY", rdfvalue.Duration(0)
  )
  def testErrorsWhenDownloadingFileAndNotReceivingBlobs(self):
    paths = [os.path.join(self.base_path, "test.plist")]
    action = rdf_file_finder.FileFinderAction(
        action_type=rdf_file_finder.FileFinderAction.Action.DOWNLOAD
    )

    # Make sure BlobHandler doesn't accept any incoming blobs. Thus
    # ClientFileFinder will timeout waiting for one.
    with mock.patch.object(transfer.BlobHandler, "ProcessMessages"):
      flow_id = flow_test_lib.StartFlow(
          file_finder.ClientFileFinder,
          client_id=self.client_id,
          paths=paths,
          pathtype=rdf_paths.PathSpec.PathType.OS,
          action=action,
          creator=self.test_username,
      )
      with self.assertRaisesRegex(
          RuntimeError, "Could not find one of referenced blobs"
      ):
        flow_test_lib.RunFlow(
            client_id=self.client_id,
            flow_id=flow_id,
            client_mock=action_mocks.ClientFileFinderClientMock(),
        )

    flow_state = flow_test_lib.GetFlowState(self.client_id, flow_id)
    # Check that the flow has actually reached the maximum number of checks.
    self.assertEqual(
        flow_state.num_blob_waits,
        file_finder.ClientFileFinder.MAX_BLOB_CHECKS + 1,
    )

  def testUseExternalStores(self):
    paths = [os.path.join(self.base_path, "test.plist")]
    action = rdf_file_finder.FileFinderAction(
        action_type=rdf_file_finder.FileFinderAction.Action.DOWNLOAD)

    action.download.use_external_stores = False

    with mock.patch.object(file_store.EXTERNAL_FILE_STORE, "AddFiles") as efs:
      flow_id = flow_test_lib.TestFlowHelper(
          file_finder.ClientFileFinder.__name__,
          action_mocks.ClientFileFinderClientMock(),
          client_id=self.client_id,
          paths=paths,
          pathtype=rdf_paths.PathSpec.PathType.OS,
          action=action,
          process_non_regular_files=True,
          creator=self.test_username)

    results = flow_test_lib.GetFlowResults(self.client_id, flow_id)
    self.assertLen(results, 1)

    self.assertEqual(efs.call_count, 0)

    action.download.use_external_stores = True

    with mock.patch.object(file_store.EXTERNAL_FILE_STORE, "AddFiles") as efs:
      flow_id = flow_test_lib.TestFlowHelper(
          file_finder.ClientFileFinder.__name__,
          action_mocks.ClientFileFinderClientMock(),
          client_id=self.client_id,
          paths=paths,
          pathtype=rdf_paths.PathSpec.PathType.OS,
          action=action,
          process_non_regular_files=True,
          creator=self.test_username)

    results = flow_test_lib.GetFlowResults(self.client_id, flow_id)
    self.assertLen(results, 1)

    self.assertEqual(efs.call_count, 1)

  def _VerifyDownloadedFiles(self, results):
    for r in results:
      original_path = r.stat_entry.pathspec.path
      fd = file_store.OpenFile(
          db.ClientPath(
              self.client_id,
              rdf_objects.PathInfo.PathType.OS,
              components=original_path.strip("/").split("/")))

      with io.open(original_path, "rb") as orig_fd:
        orig_content = orig_fd.read()

      orig_sha256 = hashlib.sha256(orig_content).digest()

      self.assertEqual(fd.read(), orig_content)
      self.assertEqual(r.hash_entry.sha256, orig_sha256)

  def testFileWithMoreThanOneChunk(self):
    path = os.path.join(self.base_path, "History.plist")
    s = os.stat(path).st_size
    action = rdf_file_finder.FileFinderAction.Download(chunk_size=s // 4)

    flow_id = flow_test_lib.TestFlowHelper(
        file_finder.ClientFileFinder.__name__,
        action_mocks.ClientFileFinderClientMock(),
        client_id=self.client_id,
        paths=[path],
        pathtype=rdf_paths.PathSpec.PathType.OS,
        action=action,
        process_non_regular_files=True,
        creator=self.test_username)

    results = flow_test_lib.GetFlowResults(self.client_id, flow_id)

    self.assertLen(results, 1)

    self._VerifyDownloadedFiles(results)

  def testFileWithExactlyThanOneChunk(self):
    path = os.path.join(self.base_path, "History.plist")
    s = os.stat(path).st_size
    action = rdf_file_finder.FileFinderAction.Download(chunk_size=s * 2)

    flow_id = flow_test_lib.TestFlowHelper(
        file_finder.ClientFileFinder.__name__,
        action_mocks.ClientFileFinderClientMock(),
        client_id=self.client_id,
        paths=[path],
        pathtype=rdf_paths.PathSpec.PathType.OS,
        action=action,
        process_non_regular_files=True,
        creator=self.test_username)

    results = flow_test_lib.GetFlowResults(self.client_id, flow_id)

    self.assertLen(results, 1)

    self._VerifyDownloadedFiles(results)

  def testClientFileFinderDownload(self):
    paths = [os.path.join(self.base_path, "{**,.}/*.plist")]
    action = rdf_file_finder.FileFinderAction.Action.DOWNLOAD
    results, _ = self._RunCFF(paths, action)

    self.assertLen(results, 5)
    relpaths = [
        os.path.relpath(p.stat_entry.pathspec.path, self.base_path)
        for p in results
    ]
    self.assertCountEqual(relpaths, [
        "History.plist", "History.xml.plist", "test.plist",
        "parser_test/com.google.code.grr.plist",
        "parser_test/InstallHistory.plist"
    ])

    self._VerifyDownloadedFiles(results)

  def testClientFileFinderPathCasing(self):
    paths = [
        os.path.join(self.base_path, "PARSER_TEST/*.plist"),
        os.path.join(self.base_path, "history.plist"),
        os.path.join(self.base_path, "InstallHistory.plist")
    ]
    action = rdf_file_finder.FileFinderAction.Action.STAT
    results, _ = self._RunCFF(paths, action)
    self.assertLen(results, 3)
    relpaths = [
        os.path.relpath(p.stat_entry.pathspec.path, self.base_path)
        for p in results
    ]
    self.assertCountEqual(relpaths, [
        "History.plist", "parser_test/InstallHistory.plist",
        "parser_test/com.google.code.grr.plist"
    ])

  def _SetupUnicodePath(self, path):
    try:
      dir_path = os.path.join(path, u"厨房")
      os.mkdir(dir_path)
    except UnicodeEncodeError:
      self.skipTest("Test needs a unicode capable file system.")

    file_path = os.path.join(dir_path, u"卫浴洁.txt")

    with io.open(file_path, "w") as f:
      f.write(u"hello world!")

  def testClientFileFinderUnicodeRegex(self):
    self._SetupUnicodePath(self.temp_dir)
    paths = [
        os.path.join(self.temp_dir, "*"),
        os.path.join(self.temp_dir, u"厨房/*.txt")
    ]
    action = rdf_file_finder.FileFinderAction.Action.STAT
    results, _ = self._RunCFF(paths, action)
    self.assertLen(results, 2)
    relpaths = [
        os.path.relpath(p.stat_entry.pathspec.path, self.temp_dir)
        for p in results
    ]
    self.assertCountEqual(relpaths, [u"厨房", u"厨房/卫浴洁.txt"])

  def testClientFileFinderUnicodeLiteral(self):
    self._SetupUnicodePath(self.temp_dir)

    paths = [os.path.join(self.temp_dir, u"厨房/卫浴洁.txt")]
    action = rdf_file_finder.FileFinderAction.Action.STAT
    results, _ = self._RunCFF(paths, action)
    self.assertLen(results, 1)
    relpaths = [
        os.path.relpath(p.stat_entry.pathspec.path, self.temp_dir)
        for p in results
    ]
    self.assertCountEqual(relpaths, [u"厨房/卫浴洁.txt"])

  def testPathInterpolation(self):
    bar = rdf_client.User(username="bar")
    baz = rdf_client.User(username="baz")
    self.client_id = self.SetupClient(
        0, system="foo", fqdn="norf", users=[bar, baz])

    with temp.AutoTempDirPath(remove_non_empty=True) as temp_dirpath:
      self._Touch(os.path.join(temp_dirpath, "foo", "bar"))
      self._Touch(os.path.join(temp_dirpath, "foo", "baz"))
      self._Touch(os.path.join(temp_dirpath, "foo", "quux"))
      self._Touch(os.path.join(temp_dirpath, "thud", "norf", "plugh"))
      self._Touch(os.path.join(temp_dirpath, "thud", "norf", "blargh"))

      paths = [
          os.path.join(temp_dirpath, "%%os%%", "%%users.username%%"),
          os.path.join(temp_dirpath, "thud", "%%fqdn%%", "plugh"),
      ]

      action = rdf_file_finder.FileFinderAction.Action.STAT
      results, flow_id = self._RunCFF(paths, action)

      result_paths = [result.stat_entry.pathspec.path for result in results]
      self.assertCountEqual(result_paths, [
          os.path.join(temp_dirpath, "foo", "bar"),
          os.path.join(temp_dirpath, "foo", "baz"),
          os.path.join(temp_dirpath, "thud", "norf", "plugh")
      ])

    # Also check that the argument protobuf still has the original values.
    flow_obj = flow_test_lib.GetFlowObj(self.client_id, flow_id)
    args = flow_obj.args
    self.assertCountEqual(args.paths, paths)

  # TODO(hanuszczak): Similar function can be found in other modules. It should
  # be implemented once in the test library.
  def _Touch(self, filepath):
    dirpath = os.path.dirname(filepath)
    if not os.path.exists(dirpath):
      os.makedirs(dirpath)

    with io.open(filepath, "wb"):
      pass

  def testLinksAndContent(self):
    with temp.AutoTempDirPath(remove_non_empty=True) as tempdir:
      # This sets up a structure as follows:
      # <dir>  tempdir/dir
      # <file> tempdir/foo
      # <lnk>  tempdir/foo_lnk
      # <lnk>  tempdir/dir_lnk

      # foo_lnk is a symbolic link to foo (a file).
      # dir_lnk is a symbolic link to dir (a directory).

      path = os.path.join(tempdir, "foo")
      with io.open(path, "w") as fd:
        fd.write("some content")

      dir_path = os.path.join(tempdir, "dir")
      os.mkdir(dir_path)

      lnk_path = os.path.join(tempdir, "foo_lnk")
      os.symlink(path, lnk_path)

      dir_lnk_path = os.path.join(tempdir, "dir_lnk")
      os.symlink(dir_path, dir_lnk_path)

      path_glob = os.path.join(tempdir, "**3")
      action = rdf_file_finder.FileFinderAction.Action.STAT
      condition = rdf_file_finder.FileFinderCondition.ContentsLiteralMatch(
          literal=b"some")

      results, _ = self._RunCFF([path_glob], action, conditions=[condition])

      # ClientFileFinder follows links that point to regulat files by default,
      # hence 2 results: one for the link and one for the file.
      self.assertLen(results, 2)
      self.assertCountEqual(
          [
              results[0].stat_entry.pathspec.path,
              results[1].stat_entry.pathspec.path,
          ],
          [path, lnk_path],
      )

  def testInterpolationMissingAttributes(self):
    creator = db_test_utils.InitializeUser(data_store.REL_DB)
    client_id = db_test_utils.InitializeClient(data_store.REL_DB)

    # We need to write some dummy snapshot to ensure the knowledgebase is there.
    snapshot = objects_pb2.ClientSnapshot()
    snapshot.client_id = client_id
    snapshot.knowledge_base.fqdn = "foobar.example.com"
    data_store.REL_DB.WriteClientSnapshot(snapshot)

    flow_args = rdf_file_finder.FileFinderArgs()
    flow_args.action = rdf_file_finder.FileFinderAction.Stat()
    flow_args.paths = ["%%environ_path%%", "%%environ_temp%%"]

    flow_id = flow_test_lib.StartFlow(
        file_finder.ClientFileFinder,
        creator=creator,
        client_id=client_id,
        flow_args=flow_args)

    flow_obj = data_store.REL_DB.ReadFlowObject(client_id, flow_id)
    self.assertEqual(flow_obj.flow_state, flows_pb2.Flow.FlowState.ERROR)
    self.assertIn("Missing knowledgebase attributes", flow_obj.error_message)

    log_entries = data_store.REL_DB.ReadFlowLogEntries(
        client_id=client_id, flow_id=flow_id, offset=0, count=1024)
    self.assertLen(log_entries, 2)
    self.assertIn("environ_path", log_entries[0].message)
    self.assertIn("environ_temp", log_entries[1].message)

  def testInterpolationUnknownAttributes(self):
    creator = db_test_utils.InitializeUser(data_store.REL_DB)
    client_id = db_test_utils.InitializeClient(data_store.REL_DB)

    # We need to write some dummy snapshot to ensure the knowledgebase is there.
    snapshot = objects_pb2.ClientSnapshot()
    snapshot.client_id = client_id
    snapshot.knowledge_base.fqdn = "foobar.example.com"
    data_store.REL_DB.WriteClientSnapshot(snapshot)

    flow_args = rdf_file_finder.FileFinderArgs()
    flow_args.action = rdf_file_finder.FileFinderAction.Stat()
    flow_args.paths = ["%%foo%%", "%%bar%%"]

    flow_id = flow_test_lib.StartFlow(
        file_finder.ClientFileFinder,
        creator=creator,
        client_id=client_id,
        flow_args=flow_args)

    flow_obj = data_store.REL_DB.ReadFlowObject(client_id, flow_id)
    self.assertEqual(flow_obj.flow_state, flows_pb2.Flow.FlowState.ERROR)
    self.assertIn("Unknown knowledgebase attributes", flow_obj.error_message)

    log_entries = data_store.REL_DB.ReadFlowLogEntries(
        client_id=client_id, flow_id=flow_id, offset=0, count=1024)
    self.assertLen(log_entries, 2)
    self.assertIn("foo", log_entries[0].message)
    self.assertIn("bar", log_entries[1].message)

  def testSkipsGlobsWithInterpolationWhenNoKnowledgeBase(self):
    creator = db_test_utils.InitializeUser(data_store.REL_DB)
    client_id = db_test_utils.InitializeClient(data_store.REL_DB)

    # We do not write any snapshot not to have any knowledgebase for the client.

    flow_args = rdf_file_finder.FileFinderArgs()
    flow_args.action = rdf_file_finder.FileFinderAction.Stat()
    flow_args.paths = ["/var/foo", "%%os%%"]

    flow_id = flow_test_lib.StartFlow(
        file_finder.ClientFileFinder,
        creator=creator,
        client_id=client_id,
        flow_args=flow_args,
    )

    flow_obj = data_store.REL_DB.ReadFlowObject(client_id, flow_id)
    self.assertEqual(flow_obj.flow_state, flows_pb2.Flow.FlowState.RUNNING)
    log_entries = data_store.REL_DB.ReadFlowLogEntries(
        client_id=client_id, flow_id=flow_id, offset=0, count=1024
    )
    self.assertLen(log_entries, 1)
    self.assertIn(
        "Skipping glob '%%os%%': can't interpolate with an empty knowledge"
        " base",
        log_entries[0].message,
    )

  def testFailsIfAllGlobsWithAreSkippedDueToNoKnowledgeBase(self):
    creator = db_test_utils.InitializeUser(data_store.REL_DB)
    client_id = db_test_utils.InitializeClient(data_store.REL_DB)

    # We do not write any snapshot not to have any knowledgebase for the client.

    flow_args = rdf_file_finder.FileFinderArgs()
    flow_args.action = rdf_file_finder.FileFinderAction.Stat()
    flow_args.paths = ["%%os%%"]

    flow_id = flow_test_lib.StartFlow(
        file_finder.ClientFileFinder,
        creator=creator,
        client_id=client_id,
        flow_args=flow_args)

    flow_obj = data_store.REL_DB.ReadFlowObject(client_id, flow_id)
    self.assertEqual(flow_obj.flow_state, flows_pb2.Flow.FlowState.ERROR)
    self.assertIn(
        "All globs skipped, as there's no knowledgebase available for"
        " interpolation",
        flow_obj.error_message,
    )


def main(argv):
  # Run the full test suite
  test_lib.main(argv)


if __name__ == "__main__":
  app.run(main)
