Images file format 1.0

images.json files provide details about images included in composes.

File Format

Compose images metadata is stored as a JSON serialized dictionary. It’s recommended to sort keys alphabetically and use 4 spaces for indentation in order to read and diff images.json files easily.

    "header": {
        "version": "1.0"                            # metadata version; format: $major<int>.$minor<int>
    "payload": {
        "compose": {                                # see composeinfo for details
            "date": <str>,
            "id": <str>,
            "respin": <int>,
            "type": <str>
        "images": {
            variant_uid<str>: {                     # compose variant UID
                arch<str>: [                        # compose variant arch
                        "arch": <str>,              # image arch
                        "bootable": <bool>,         # can the image be booted?
                        "checksums": {
                            type<str>: <str>        #
                        "disc_count": <int>,        # number of discs in media set
                        "disc_number": <int>,       # disc number
                        "format": <str>,            # see productmd.images.SUPPORTED_IMAGE_FORMATS
                        "implant_md5": <str|null>,  # md5 checksum implanted directly on media (see implantisomd5 and checkisomd5 commands)
                        "mtime": <int>,             # mtime of the image stored as a decimal unix timestamp
                        "path": <str>,              # relative path to the image
                        "size": <int>,              # file size of the image
                        "type": <str>,              # see productmd.images.SUPPORTED_IMAGE_TYPES
                        "volume_id": <str|null>     # volume ID; null if not available/applicable