func addRU(c *gc.C, svc *state.Service, rel *state.Relation, principal *state.Unit) (*state.Unit, *state.RelationUnit) {
// Given the service svc in the relation rel, add a unit of svc and create
// a RelationUnit with rel. If principal is supplied, svc is assumed to be
// subordinate and the unit will be created by temporarily entering the
// relation's scope as the principal.
var u *state.Unit
if principal == nil {
unit, err := svc.AddUnit()
c.Assert(err, gc.IsNil)
u = unit
} else {
origUnits, err := svc.AllUnits()
c.Assert(err, gc.IsNil)
pru, err := rel.Unit(principal)
c.Assert(err, gc.IsNil)
err = pru.EnterScope(nil) // to create the subordinate
c.Assert(err, gc.IsNil)
err = pru.LeaveScope() // to reset to initial expected state
c.Assert(err, gc.IsNil)
newUnits, err := svc.AllUnits()
c.Assert(err, gc.IsNil)
for _, unit := range newUnits {
found := false
for _, old := range origUnits {
if unit.Name() == old.Name() {
found = true
break
}
}
if !found {
u = unit
break
}
}
c.Assert(u, gc.NotNil)
}
preventUnitDestroyRemove(c, u)
ru, err := rel.Unit(u)
c.Assert(err, gc.IsNil)
return u, ru
}
func (u *UniterAPI) prepareRelationResult(rel *state.Relation, unit *state.Unit) (params.RelationResult, error) {
nothing := params.RelationResult{}
ep, err := rel.Endpoint(unit.ServiceName())
if err != nil {
// An error here means the unit's service is not part of the
// relation.
return nothing, err
}
return params.RelationResult{
Id: rel.Id(),
Key: rel.String(),
Life: params.Life(rel.Life().String()),
Endpoint: params.Endpoint{
ServiceName: ep.ServiceName,
Relation: ep.Relation,
},
}, nil
}