// GetPrincipal returns the result of calling PrincipalName() and
// converting it to a tag, on each given unit.
func (u *UniterAPI) GetPrincipal(args params.Entities) (params.StringBoolResults, error) {
result := params.StringBoolResults{
Results: make([]params.StringBoolResult, len(args.Entities)),
}
canAccess, err := u.accessUnit()
if err != nil {
return params.StringBoolResults{}, err
}
for i, entity := range args.Entities {
err := common.ErrPerm
if canAccess(entity.Tag) {
var unit *state.Unit
unit, err = u.getUnit(entity.Tag)
if err == nil {
principal, ok := unit.PrincipalName()
if principal != "" {
result.Results[i].Result = names.UnitTag(principal)
}
result.Results[i].Ok = ok
}
}
result.Results[i].Error = common.ServerError(err)
}
return result, nil
}
// matchUnit attempts to match a state.Unit to one of
// a set of patterns, taking into account subordinate
// relationships.
func (m unitMatcher) matchUnit(u *state.Unit) bool {
if m.matchesAny() {
return true
}
// Keep the unit if:
// (a) its name matches a pattern, or
// (b) it's a principal and one of its subordinates matches, or
// (c) it's a subordinate and its principal matches.
//
// Note: do *not* include a second subordinate if the principal is
// only matched on account of a first subordinate matching.
if m.matchString(u.Name()) {
return true
}
if u.IsPrincipal() {
for _, s := range u.SubordinateNames() {
if m.matchString(s) {
return true
}
}
return false
}
principal, valid := u.PrincipalName()
if !valid {
panic("PrincipalName failed for subordinate unit")
}
return m.matchString(principal)
}
