Hieroglyph

"In Neoplatonism, especially during the Renaissance, a 'hieroglyph' was an artistic representation of an esoteric idea" - https://en.wikipedia.org/wiki/Hieroglyph

This Cloud Foundry CLI plugin, and Golang library, allows you to attach and retrieve data for a Cloud Foundry Service Instance, useful for non-core systems to attach data to a service instance (such as the URL for the latest backup of a postgresql or redis database).

As a CLI, first target the org/space:

cf target -o org -s space

To set a key-value pair for a service instance:

cf hieroglyph <service-instance-name> author drnic

To get a value stored for a key on a service instance:

cf hieroglyph <service-instance-name> author
drnic

To delete a key-value pair:

cf hieroglyph <service-instance-name> -d author

To view all key-valye pairs:

cf hieroglyph <service-instance-name>

Implementation details

This data is stored in the only available read-writeable aspect of a service instance: its tags.

cf curl "/v2/service_instances?q=name:<service-instance-name>"
{
   "resources": [
      {
         "entity": {
            "name": "restore-mydb",
            "tags": ["author:drnic"],
            ...
         }
      }
   ]
}

Non-trivial values are first base64 encoded, and the above might appear as:

"tags": ["author:ZHJuaWMK"],

Yeah, that's esoteric. But its the only way we could figure out how to store data against a service instance that was available to the majority of Cloud Foundry installations in 2015.

drnic/cf-hieroglyph.md

Hieroglyph

Implementation details