| 1 | package legatus |
| 2 | |
| 3 | // Host is a single SSH target the orchestrator can act on. |
| 4 | type Host struct { |
| 5 | Name string |
| 6 | Addr string |
| 7 | Port int |
| 8 | User string |
| 9 | Tags []string |
| 10 | Groups []string |
| 11 | Vars map[string]any |
| 12 | } |
| 13 | |
| 14 | // Selector reports whether a host belongs to a selection. Selectors are pure |
| 15 | // predicates over a Host so they compose without reaching back into Inventory. |
| 16 | type Selector func(*Host) bool |
| 17 | |
| 18 | // ByName selects hosts whose Name is in names. |
| 19 | func ByName(names ...string) Selector { |
| 20 | set := make(map[string]struct{}, len(names)) |
| 21 | for _, n := range names { |
| 22 | set[n] = struct{}{} |
| 23 | } |
| 24 | return func(h *Host) bool { |
| 25 | _, ok := set[h.Name] |
| 26 | return ok |
| 27 | } |
| 28 | } |
| 29 | |
| 30 | // ByTag selects hosts carrying any of the given tags. |
| 31 | func ByTag(tags ...string) Selector { |
| 32 | return func(h *Host) bool { |
| 33 | return containsAny(h.Tags, tags) |
| 34 | } |
| 35 | } |
| 36 | |
| 37 | // InGroup selects hosts that are members of the named group. |
| 38 | func InGroup(group string) Selector { |
| 39 | return func(h *Host) bool { |
| 40 | return containsAny(h.Groups, []string{group}) |
| 41 | } |
| 42 | } |
| 43 | |
| 44 | func containsAny(have, want []string) bool { |
| 45 | for _, w := range want { |
| 46 | for _, h := range have { |
| 47 | if h == w { |
| 48 | return true |
| 49 | } |
| 50 | } |
| 51 | } |
| 52 | return false |
| 53 | } |
| 54 | |
| 55 | // Inventory is the set of hosts an orchestration runs against. |
| 56 | type Inventory struct { |
| 57 | hosts []*Host |
| 58 | } |
| 59 | |
| 60 | // NewInventory builds an inventory from the given hosts. |
| 61 | func NewInventory(hosts ...*Host) *Inventory { |
| 62 | inv := &Inventory{} |
| 63 | inv.hosts = append(inv.hosts, hosts...) |
| 64 | return inv |
| 65 | } |
| 66 | |
| 67 | // Add appends a host to the inventory. |
| 68 | func (inv *Inventory) Add(h *Host) { inv.hosts = append(inv.hosts, h) } |
| 69 | |
| 70 | // Hosts returns the hosts matching every selector (logical AND). With no |
| 71 | // selectors it returns all hosts. |
| 72 | func (inv *Inventory) Hosts(sel ...Selector) []*Host { |
| 73 | var out []*Host |
| 74 | for _, h := range inv.hosts { |
| 75 | if matchAll(h, sel) { |
| 76 | out = append(out, h) |
| 77 | } |
| 78 | } |
| 79 | return out |
| 80 | } |
| 81 | |
| 82 | // Group returns the hosts that are members of the named group. |
| 83 | func (inv *Inventory) Group(name string) []*Host { |
| 84 | return inv.Hosts(InGroup(name)) |
| 85 | } |
| 86 | |
| 87 | func matchAll(h *Host, sel []Selector) bool { |
| 88 | for _, s := range sel { |
| 89 | if !s(h) { |
| 90 | return false |
| 91 | } |
| 92 | } |
| 93 | return true |
| 94 | } |
| 95 | |