func (i *importer) constraints(cons description.Constraints) constraints.Value {
var result constraints.Value
if cons == nil {
return result
}
if arch := cons.Architecture(); arch != "" {
result.Arch = &arch
}
if container := instance.ContainerType(cons.Container()); container != "" {
result.Container = &container
}
if cores := cons.CpuCores(); cores != 0 {
result.CpuCores = &cores
}
if power := cons.CpuPower(); power != 0 {
result.CpuPower = &power
}
if inst := cons.InstanceType(); inst != "" {
result.InstanceType = &inst
}
if mem := cons.Memory(); mem != 0 {
result.Mem = &mem
}
if disk := cons.RootDisk(); disk != 0 {
result.RootDisk = &disk
}
if spaces := cons.Spaces(); len(spaces) > 0 {
result.Spaces = &spaces
}
if tags := cons.Tags(); len(tags) > 0 {
result.Tags = &tags
}
return result
}
// MatchingInstanceTypes returns all instance types matching constraints and available
// in region, sorted by increasing region-specific cost (if known).
func MatchingInstanceTypes(allInstanceTypes []InstanceType, region string, cons constraints.Value) ([]InstanceType, error) {
var itypes []InstanceType
// Rules used to select instance types:
// - non memory constraints like cpu-cores etc are always honoured
// - if no mem constraint specified and instance-type not specified,
// try opinionated default with enough mem to run a server.
// - if no matches and no mem constraint specified, try again and
// return any matching instance with the largest memory
origCons := cons
if !cons.HasInstanceType() && cons.Mem == nil {
minMem := uint64(minMemoryHeuristic)
cons.Mem = &minMem
}
itypes = matchingTypesForConstraint(allInstanceTypes, cons)
// No matches using opinionated default, so if no mem constraint specified,
// look for matching instance with largest memory.
if len(itypes) == 0 && cons.Mem != origCons.Mem {
itypes = matchingTypesForConstraint(allInstanceTypes, origCons)
if len(itypes) > 0 {
sort.Sort(byMemory(itypes))
itypes = []InstanceType{itypes[len(itypes)-1]}
}
}
// If we have matching instance types, we can return those, sorted by cost.
if len(itypes) > 0 {
sort.Sort(byCost(itypes))
return itypes, nil
}
// No luck, so report the error.
return nil, fmt.Errorf("no instance types in %s matching constraints %q", region, origCons)
}
func (s *constraintsSuite) TestConstraints(c *gc.C) {
for i, t := range newConstraintTests {
var cv constraints.Value
if t.arch != nil {
cv.Arch = &t.arch.v
}
if t.cores != nil {
cv.CpuCores = &t.cores.v
}
if t.power != nil {
cv.CpuPower = &t.power.v
}
if t.mem != nil {
cv.Mem = &t.mem.v
}
if t.disk != nil {
cv.RootDisk = &t.disk.v
}
v := newConstraints(t.bootstrap, cv, img)
if !c.Check(*v, gc.Equals, t.expected) {
c.Logf("test (%d): %+v", i, t)
}
}
}
