Capabilities

A group member’s capabilities are a u32 bitmask, carried as a Long in Kotlin (so the full unsigned range stays a positive value). Capabilities exposes the bit constants core assigns, plus helpers for reading and editing a mask. Use them with the group capability methods on mero.admin (getMemberCapabilities, setMemberCapabilities, getDefaultCapabilities, setDefaultCapabilities). The groups & governance guide shows a full flow.

Constants

Core MemberCapabilities, bits 0–8 (all const val … : Long):

object Capabilities {
    const val CAN_CREATE_CONTEXT     = 1L       // 1 shl 0
    const val CAN_INVITE_MEMBERS      = 2L       // 1 shl 1
    const val CAN_JOIN_OPEN_SUBGROUPS = 4L       // 1 shl 2
    const val MANAGE_MEMBERS          = 8L       // 1 shl 3
    const val MANAGE_APPLICATION      = 16L      // 1 shl 4
    const val CAN_CREATE_SUBGROUP     = 32L      // 1 shl 5
    const val CAN_DELETE_SUBGROUP     = 64L      // 1 shl 6
    const val CAN_MANAGE_VISIBILITY   = 128L     // 1 shl 7
    const val CAN_MANAGE_METADATA     = 256L     // 1 shl 8
}

Caution

Bits 9 and above are unassigned and reserved for future core releases — do not repurpose them for application data.

Helpers

All normalize to the unsigned 32-bit range.

fun hasCap(mask: Long, cap: Long): Boolean   // every bit of cap set?
fun withCap(mask: Long, cap: Long): Long     // mask with cap set
fun withoutCap(mask: Long, cap: Long): Long  // mask with cap cleared

Example

import com.calimero.mero.Capabilities

// MemberCapabilities.capabilities is an Int; the helpers work on Long.
val current = mero.admin.getMemberCapabilities(groupId, identity = id).capabilities
var mask = current.toLong()

if (!Capabilities.hasCap(mask, Capabilities.CAN_INVITE_MEMBERS)) {
    mask = Capabilities.withCap(mask, Capabilities.CAN_INVITE_MEMBERS)
    mask = Capabilities.withCap(mask, Capabilities.CAN_CREATE_SUBGROUP)
    mask = Capabilities.withoutCap(mask, Capabilities.CAN_MANAGE_METADATA)
    mero.admin.setMemberCapabilities(
        groupId, identity = id, SetMemberCapabilitiesRequest(capabilities = mask.toInt())
    )
}