From 84451b2bd83be63651bf9ac5c0aca2eb7caa62f5 Mon Sep 17 00:00:00 2001
From: Virgil <virgil@lethean.io>
Date: Thu, 2 Apr 2026 02:07:09 +0000
Subject: [PATCH] feat(ansible): support top-level inventory groups

Co-authored-by: Virgil <virgil@lethean.io>
---
 parser_test.go |  35 +++++++++++++++++
 types.go       | 100 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 135 insertions(+)

diff --git a/parser_test.go b/parser_test.go
index 7a5af56..e7432fc 100644
--- a/parser_test.go
+++ b/parser_test.go
@@ -525,6 +525,41 @@ all:
 	assert.Len(t, inv.All.Children["databases"].Hosts, 1)
 }
 
+func TestParser_ParseInventory_Good_TopLevelGroups(t *testing.T) {
+	dir := t.TempDir()
+	path := joinPath(dir, "inventory.yml")
+
+	yaml := `---
+webservers:
+  vars:
+    tier: web
+  hosts:
+    web1:
+      ansible_host: 10.0.0.1
+    web2:
+      ansible_host: 10.0.0.2
+databases:
+  hosts:
+    db1:
+      ansible_host: 10.0.1.1
+`
+	require.NoError(t, writeTestFile(path, []byte(yaml), 0644))
+
+	p := NewParser(dir)
+	inv, err := p.ParseInventory(path)
+
+	require.NoError(t, err)
+	require.NotNil(t, inv.All)
+	require.NotNil(t, inv.All.Children["webservers"])
+	require.NotNil(t, inv.All.Children["databases"])
+	assert.Len(t, inv.All.Children["webservers"].Hosts, 2)
+	assert.Len(t, inv.All.Children["databases"].Hosts, 1)
+	assert.Equal(t, "web", inv.All.Children["webservers"].Vars["tier"])
+	assert.ElementsMatch(t, []string{"web1", "web2", "db1"}, GetHosts(inv, "all"))
+	assert.Equal(t, []string{"web1", "web2"}, GetHosts(inv, "webservers"))
+	assert.Equal(t, "web", GetHostVars(inv, "web1")["tier"])
+}
+
 func TestParser_ParseInventory_Good_WithVars(t *testing.T) {
 	dir := t.TempDir()
 	path := joinPath(dir, "inventory.yml")
diff --git a/types.go b/types.go
index 295743d..1ca06ab 100644
--- a/types.go
+++ b/types.go
@@ -2,6 +2,9 @@ package ansible
 
 import (
 	"time"
+
+	coreerr "dappco.re/go/core/log"
+	"gopkg.in/yaml.v3"
 )
 
 // Playbook represents an Ansible playbook.
@@ -205,6 +208,103 @@ type Inventory struct {
 	All *InventoryGroup `yaml:"all"`
 }
 
+// UnmarshalYAML supports both the explicit `all:` root and inventories that
+// declare top-level groups directly.
+func (i *Inventory) UnmarshalYAML(unmarshal func(any) error) error {
+	var raw map[string]any
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	root := &InventoryGroup{}
+	rootInput := make(map[string]any)
+	if all, ok := raw["all"]; ok {
+		group, err := decodeInventoryGroupValue(all)
+		if err != nil {
+			return coreerr.E("Inventory.UnmarshalYAML", "decode all group", err)
+		}
+		root = group
+	}
+
+	for name, value := range raw {
+		if name == "all" {
+			continue
+		}
+
+		switch name {
+		case "hosts", "children", "vars":
+			rootInput[name] = value
+			continue
+		}
+
+		group, err := decodeInventoryGroupValue(value)
+		if err != nil {
+			return coreerr.E("Inventory.UnmarshalYAML", "decode group "+name, err)
+		}
+
+		if root.Children == nil {
+			root.Children = make(map[string]*InventoryGroup)
+		}
+		root.Children[name] = group
+	}
+
+	if len(rootInput) > 0 {
+		extra, err := decodeInventoryGroupValue(rootInput)
+		if err != nil {
+			return coreerr.E("Inventory.UnmarshalYAML", "decode root group", err)
+		}
+		mergeInventoryGroups(root, extra)
+	}
+
+	i.All = root
+	return nil
+}
+
+func decodeInventoryGroupValue(value any) (*InventoryGroup, error) {
+	if value == nil {
+		return &InventoryGroup{}, nil
+	}
+
+	data, err := yaml.Marshal(value)
+	if err != nil {
+		return nil, err
+	}
+
+	var group InventoryGroup
+	if err := yaml.Unmarshal(data, &group); err != nil {
+		return nil, err
+	}
+
+	return &group, nil
+}
+
+func mergeInventoryGroups(dst, src *InventoryGroup) {
+	if dst == nil || src == nil {
+		return
+	}
+
+	if dst.Hosts == nil && len(src.Hosts) > 0 {
+		dst.Hosts = make(map[string]*Host, len(src.Hosts))
+	}
+	for name, host := range src.Hosts {
+		dst.Hosts[name] = host
+	}
+
+	if dst.Children == nil && len(src.Children) > 0 {
+		dst.Children = make(map[string]*InventoryGroup, len(src.Children))
+	}
+	for name, child := range src.Children {
+		dst.Children[name] = child
+	}
+
+	if dst.Vars == nil && len(src.Vars) > 0 {
+		dst.Vars = make(map[string]any, len(src.Vars))
+	}
+	for key, value := range src.Vars {
+		dst.Vars[key] = value
+	}
+}
+
 // InventoryGroup represents a group in inventory.
 //
 // Example: