Data Object: object_tags

The hops::MHO_ObjectTags class is used as a means to attach arbitrary information to a separate object or collection of objects. The object collection associated with a particular object tag object is specified by a list of object unique identifiers (UUIDs) stored as strings. The objects with the associated UUIDs are generally contained in the same file, or if in memory, in the same hops::MHO_ContainerStore. The underlying type of the MHO_ObjectTags class is a json object provided by the external nlohmann::json library.

General Information

Class: hops::MHO_ObjectTags
Class UUID: 330c5f9889eaa350f8955c6e709a536c

Tags

The object collection is referenced by a list of 128 bit object UUIDs. The object UUIDs are stored as hex-strings (e.g. “c159826f284e416985db47c926080274”) under a list object called object_uuids. The UUIDs stored here are also present in the object file keys (hops::MHO_FileKey) that precede the binary data of each respective object in a file. In memory objects can also be retrieved from the container store (hops::MHO_ContainerStore) using the same unique object UUID as a key.

The meta-data tags (key:value pairs) that are associated with the object collection, can take on any nested structure that is available to the json format. However, the top level object which contains all such information is called tags. For example, in the fourfit4 fringe output, much of the fringe-fitting parameters, and plotting data are stored in an MHO_ObjectTags object, under “/tags/parameters” and “/tags/plot_data”. A example portion of which looks like:

"class_name": "MHO_ObjectTags",
    "class_uuid": "330c5f9889eaa350f8955c6e709a536c",
    "object_uuids": [
        "c159826f284e416985db47c926080274"
    ],
    "tags": {
        "parameters": {
            "cmdline": {
                "accounting": false,
                "ap_per_seg": 0,
                "args": [
                    "fourfit4",
                    "-c",
                    "../../cf_3686_GEHSVY_pstokes",
                    "-P",
                    "XX",
                    "-b",
                    "GE",
                    "-m",
                    "-1",
                    "./"
                ],
                "baseline": "GE",
                "control_file": "../../cf_3686_GEHSVY_pstokes",
                "directory": "./",
                "disk_file": "",
                "exclude_autos": false,
                "first_plot_channel": 0,
                "frequency_group": "?",
                "message_level": -1,
                "polprod": "XX",
                ...
                ...
                ...
        "plot_data": {
            "AP(sec)": 1.0,
            "Amp": 4.555523059968371,
            "AprioriAccel(us/s/s)": -2.351127226975069e-06,
            "AprioriClock(usec)": 96.58727777,
            "AprioriClockrate(us/s)": 1.238e-06,
            "AprioriDelay(usec)": -426.7657403524763,
            "AprioriRate(us/s)": 0.01546835364977025,
            "BuildTime": "2025:154:194416",
            "ChannelsPlotted": [
                "a",
                "b",
                "c",
                ...
                ...
                ...