func getUsedTools(model description.Model) []params.SerializedModelTools {
// Iterate through the model for all tools, and make a map of them.
usedVersions := make(map[version.Binary]bool)
// It is most likely that the preconditions will limit the number of
// tools versions in use, but that is not relied on here.
for _, machine := range model.Machines() {
addToolsVersionForMachine(machine, usedVersions)
}
for _, application := range model.Applications() {
for _, unit := range application.Units() {
tools := unit.Tools()
usedVersions[tools.Version()] = true
}
}
out := make([]params.SerializedModelTools, 0, len(usedVersions))
for v := range usedVersions {
out = append(out, params.SerializedModelTools{
Version: v.String(),
URI: common.ToolsURL("", v),
})
}
return out
}