How to use pyfuse3 - 10 common examples

def entry_attributes(self):
        attr = pyfuse3.EntryAttributes()
        attr.st_nlink = self.refcount
        attr.st_blocks = (self.size + 511) // 512
        attr.st_ino = self.id

        # Timeout, can effectively be infinite since attribute changes
        # are only triggered by the kernel's own requests
        attr.attr_timeout = 3600
        attr.entry_timeout = 3600

        # We want our blocksize for IO as large as possible to get large
        # write requests
        attr.st_blksize = 128 * 1024

        attr.st_mode = self.mode
        attr.st_uid = self.uid
        attr.st_gid = self.gid

async def statfs(self, ctx):
        log.debug('started')

        stat_ = pyfuse3.StatvfsData()

        # Get number of blocks & inodes
        blocks = self.db.get_val("SELECT COUNT(id) FROM objects")
        inodes = self.db.get_val("SELECT COUNT(id) FROM inodes")
        size = self.db.get_val('SELECT SUM(size) FROM blocks')

        if size is None:
            size = 0

        # file system block size, i.e. the minimum amount of space that can
        # be allocated. This doesn't make much sense for S3QL, so we just
        # return the average size of stored blocks.
        stat_.f_frsize = max(4096, size // blocks) if blocks != 0 else 4096

        # This should actually be the "preferred block size for doing IO.  However, `df` incorrectly
        # interprets f_blocks, f_bfree and f_bavail in terms of f_bsize rather than f_frsize as it

def tst_bug382(self):
        dirname = self.newname()
        fullname = self.mnt_dir + "/" + dirname
        os.mkdir(fullname)
        assert stat.S_ISDIR(os.stat(fullname).st_mode)
        assert dirname in pyfuse3.listdir(self.mnt_dir)
        cmd = ('(%d, %r)' % (pyfuse3.ROOT_INODE, path2bytes(dirname))).encode()
        pyfuse3.setxattr('%s/%s' % (self.mnt_dir, CTRL_NAME), 'rmtree', cmd)
        # Invalidation is asynchronous...
        try:
            retry(5, lambda: not os.path.exists(fullname))
        except RetryTimeoutError:
            pass # assert_raises should fail
        assert_raises(FileNotFoundError, os.stat, fullname)
        assert dirname not in pyfuse3.listdir(self.mnt_dir)

async def test_getxattr(ctx):
    (fh, inode) = await ctx.server.create(ROOT_INODE, newname(ctx),
                                     file_mode(), os.O_RDWR, some_ctx)
    await ctx.server.release(fh)

    with assert_raises(FUSEError):
        await ctx.server.getxattr(inode.st_ino, b'nonexistant-attr', some_ctx)

    await ctx.server.setxattr(inode.st_ino, b'my-attr', b'strabumm!', some_ctx)
    assert await ctx.server.getxattr(inode.st_ino, b'my-attr', some_ctx) == b'strabumm!'

    await ctx.server.forget([(inode.st_ino, 1)])
    await fsck(ctx)

await ctx.server.release(fh)

    # Create
    with assert_raises(FUSEError) as cm:
        ctx.server._create(inode2.st_ino, b'dir1', dir_mode(), os.O_RDWR, some_ctx)
    assert cm.value.errno == errno.EPERM

    # Setattr
    attr = await ctx.server.getattr(inode2a.st_ino, some_ctx)
    with assert_raises(FUSEError) as cm:
        await ctx.server.setattr(inode2a.st_ino, attr, SetattrFields(update_mtime=True),
                            None, some_ctx)
    assert cm.value.errno == errno.EPERM

    # xattr
    with assert_raises(FUSEError) as cm:
        await ctx.server.setxattr(inode2.st_ino, b'name', b'value', some_ctx)
    assert cm.value.errno == errno.EPERM
    with assert_raises(FUSEError) as cm:
        await ctx.server.removexattr(inode2.st_ino, b'name', some_ctx)
    assert cm.value.errno == errno.EPERM
    await ctx.server.forget(list(ctx.server.open_inodes.items()))
    await fsck(ctx)

def tst_mkdir(self):
        dirname = self.newname()
        fullname = self.mnt_dir + "/" + dirname
        os.mkdir(fullname)
        fstat = os.stat(fullname)
        assert stat.S_ISDIR(fstat.st_mode)
        assert pyfuse3.listdir(fullname) ==  []
        assert fstat.st_nlink == 1
        assert dirname in pyfuse3.listdir(self.mnt_dir)
        os.rmdir(fullname)
        assert_raises(FileNotFoundError, os.stat, fullname)
        assert dirname not in pyfuse3.listdir(self.mnt_dir)

def tst_link(self):
        name1 = os.path.join(self.mnt_dir, self.newname())
        name2 = os.path.join(self.mnt_dir, self.newname())
        src = self.src
        shutil.copyfile(src, name1)
        assert filecmp.cmp(name1, src, False)
        os.link(name1, name2)

        fstat1 = os.lstat(name1)
        fstat2 = os.lstat(name2)

        assert fstat1 == fstat2
        assert fstat1.st_nlink == 2

        assert basename(name2) in pyfuse3.listdir(self.mnt_dir)
        assert filecmp.cmp(name1, name2, False)
        os.unlink(name2)
        fstat1 = os.lstat(name1)
        assert fstat1.st_nlink == 1
        os.unlink(name1)

def tst_readdir(self):
        dir_ = os.path.join(self.mnt_dir, self.newname())
        file_ = dir_ + "/" + self.newname()
        subdir = dir_ + "/" + self.newname()
        subfile = subdir + "/" + self.newname()
        src = self.src

        os.mkdir(dir_)
        shutil.copyfile(src, file_)
        os.mkdir(subdir)
        shutil.copyfile(src, subfile)

        listdir_is = pyfuse3.listdir(dir_)
        listdir_is.sort()
        listdir_should = [ basename(file_), basename(subdir) ]
        listdir_should.sort()
        assert listdir_is == listdir_should

        os.unlink(file_)
        os.unlink(subfile)
        os.rmdir(subdir)
        os.rmdir(dir_)

def tst_symlink(self):
        linkname = self.newname()
        fullname = self.mnt_dir + "/" + linkname
        os.symlink("/imaginary/dest", fullname)
        fstat = os.lstat(fullname)
        assert stat.S_ISLNK(fstat.st_mode)
        assert os.readlink(fullname) == "/imaginary/dest"
        assert fstat.st_nlink == 1
        assert linkname in pyfuse3.listdir(self.mnt_dir)
        os.unlink(fullname)
        assert_raises(FileNotFoundError, os.lstat, fullname)
        assert linkname not in pyfuse3.listdir(self.mnt_dir)

# Try to delete
        assert_raises(PermissionError, os.unlink, filename)

        # Try to write
        with pytest.raises(PermissionError):
            open(filename, 'w+').write('Hello')

        # delete properly
        try:
            s3ql.remove.main([tempdir])
        except:
            sys.excepthook(*sys.exc_info())
            pytest.fail("s3qlrm raised exception")

        assert 'lock_dir' not in pyfuse3.listdir(self.mnt_dir)