Implement dynamic inventory based on files only

18 files changed, 223 insertions, 15 deletions

diff --git a/dynamic.py b/dynamic.py
new file mode 100755
index 0000000..78ebdb2
--- /dev/null
+++ b/dynamic.py
@@ -0,0 +1,194 @@
+#!/usr/bin/env python3
+#
+# This is a dynamic inventory script for Ansible at
+# rgoncalves.se infrastructure.
+#
+# Only groups_vars/ and host_vars/ directory are used for setting up devices
+# and nodes.
+# > Files, files, files, ... only files, everything files!
+#
+# The main goal here is to allow flexible code reviews and edits, POSIX
+# compliant actions over files, and using "less is more" moto. Moreover, each
+# host/group/node is individually track on version control.
+
+import os
+import yaml
+import logging
+import json
+
+from typing import Final
+from optparse import OptionParser
+
+
+HOST_DIR: Final = "./host_vars"
+GROUP_DIR: Final = "./group_vars"
+
+
+class AnsibleInput:
+    """
+    AnsibleInput class mixin.
+    Meta methods and inits for reading and processing yaml files.
+    """
+
+    data = None
+    name = None
+
+    def __init__(self, filepath):
+        with open(filepath) as file:
+            self.data = yaml.load(file, Loader=yaml.FullLoader)
+            self.name = os.path.splitext(os.path.basename(filepath))[0]
+
+
+def pprint(data):
+    """
+    Json pretty print for ansible hosts/groups or whatever output we get.
+    """
+
+    try:
+        print(json.dumps(data, indent=4, sort_keys=True))
+    except TypeError:
+        print(data)
+
+
+def create_nodes(directory):
+    """
+    Build-up and ansible node (Host or Group),
+    then return the full type list.
+    """
+
+    nodes = {}
+    for file in os.scandir(directory):
+        node = AnsibleInput(file.path)
+        nodes[node.name] = node
+    return nodes
+
+
+def get_hostvars(host):
+    """
+    Retrieve and build dynamic variables for a specific host.
+    """
+
+    data = host.data
+    if "ansible_host" not in host.data:
+        data["ansible_host"] = host.name
+    return data
+
+
+def get_subgroups(groups, og):
+    """
+    Get and return all children of a specific group, in a given subset.
+    """
+
+    # specific return for group "all" 
+    if og.name in "all":
+        groups = list(groups.keys())
+        groups.remove("all")
+        return groups
+
+    # usual behavior
+    valid_groups = []
+    if "_groups" not in og.data:
+        logging.warning(f"group { og.name } does not have any _groups var!")
+    else:
+        for group in og.data["_groups"]:
+            if group in groups:
+                valid_groups.append(group)
+    return valid_groups
+
+
+def get_meta(hosts):
+    """
+    For performance reasons, return all the hosts in a meta dict.
+    """
+
+    _meta = {}
+    _meta["hostvars"] = {}
+    for hostname, host in hosts.items():
+        _meta["hostvars"][hostname] = get_hostvars(host)
+        # _meta["hostvars"][hostname] = host.data
+    return "{}"
+    return _meta
+
+
+def get_list(hosts, groups):
+    """
+    Return list of groups with all hosts.
+    """
+
+    _list = {}
+    _list["_meta"] = get_meta(hosts)
+    # init group array
+    for groupname, group in groups.items():
+        _list[groupname] = {}
+        _list[groupname]["hosts"] = []
+        _list[groupname]["vars"] = {}
+        _list[groupname]["children"] = get_subgroups(groups, group)
+    # append each hosts to their corresponding groups
+    for hostname, host in hosts.items():
+        _list["all"]["hosts"].append(hostname)
+        if "_groups" not in host.data:
+            logging.info(f"no _groups data found for host { hostname }")
+            continue
+        # retrieve _groups variables and force conversion to list
+        cleangr = host.data["_groups"]
+        cleangr = [cleangr] if isinstance(cleangr, str) else cleangr
+        for group in cleangr:
+            # skip group assignement on non-existence!
+            logging.info(f"searching for group : { group }")
+            if group not in groups:
+                logging.error(f"group { group } does not exist!")
+                continue
+            _list[group]["hosts"].append(hostname)
+    return _list
+
+
+def main():
+    """
+    Main entry.
+    """
+
+    # logging config
+    logging.basicConfig(level=logging.INFO)
+    logging.disable()
+
+    # parse cli arguments
+    parser = OptionParser()
+    parser.add_option("--host",
+                      dest="host",
+                      default="_empty",
+                      help="show specific host")
+    parser.add_option("--list",
+                      action="store_true",
+                      help="list all groups")
+    parser.add_option("--debug",
+                      action="store_true",
+                      help="show logging informations")
+    (options, args) = parser.parse_args()
+
+    # enable debug if required
+    if options.debug:
+        logging.disable(0)
+
+    # retrieve hosts and groups
+    hosts = create_nodes(HOST_DIR)
+    groups = create_nodes(GROUP_DIR)
+
+    # return specific hostname
+    if options.host != "_empty":
+        if options.host in hosts:
+            pprint(get_hostvars(hosts[options.host]))
+        else:
+            pprint("{}")
+        exit(0)
+
+    # return all groups
+    if options.list:
+        pprint(get_list(hosts, groups))
+        exit(0)
+
+    # return all hosts
+    exit(0)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/group_vars/bsd.yml b/group_vars/bsd.yml
index d2027af..95f6a17 100644
--- a/group_vars/bsd.yml
+++ b/group_vars/bsd.yml
@@ -4,6 +4,10 @@
 
 ---
 
+_groups:
+  - openbsd
+  - freebsd
+
 ansible_become_method: "doas"
 
 group_root: "wheel"
diff --git a/group_vars/linux.yml b/group_vars/linux.yml
index c11daa7..81ffaf1 100644
--- a/group_vars/linux.yml
+++ b/group_vars/linux.yml
@@ -4,6 +4,11 @@
 
 ---
 
+_groups:
+  - alpine
+  - archlinux
+  - debian
+
 ansible_become_method: "sudo"
 
 group_root: "root"
diff --git a/host_vars/dc0.yml b/host_vars/dc0.yml
index 3ef714b..c2b9df6 100644
--- a/host_vars/dc0.yml
+++ b/host_vars/dc0.yml
@@ -1,4 +1,5 @@
-ansible_host: dc0
+_groups: openbsd
+
 virtual: true
 
 ip:
diff --git a/host_vars/emb0.yml b/host_vars/emb0.yml
index 1895e48..ddb8695 100644
--- a/host_vars/emb0.yml
+++ b/host_vars/emb0.yml
@@ -1,4 +1,5 @@
-ansible_host: emb0
+_groups: debian
+
 virtual: false
 
 ip:
diff --git a/host_vars/guest0.yml b/host_vars/guest0.yml
index 76f7242..60300c2 100644
--- a/host_vars/guest0.yml
+++ b/host_vars/guest0.yml
@@ -1,4 +1,3 @@
-ansible_host: guest0
 ip:
   in: 10.10.0.100
   out: 192.168.5.100
diff --git a/host_vars/guest1.yml b/host_vars/guest1.yml
index 48702bd..8df6714 100644
--- a/host_vars/guest1.yml
+++ b/host_vars/guest1.yml
@@ -1,4 +1,3 @@
-ansible_host: guest1
 ip:
   in: 10.10.0.101
   out: 192.168.5.101
diff --git a/host_vars/guest2.yml b/host_vars/guest2.yml
index ee49906..0c10ace 100644
--- a/host_vars/guest2.yml
+++ b/host_vars/guest2.yml
@@ -1,4 +1,3 @@
-ansible_host: guest2
 ip:
   in: 10.10.0.102
   out: 192.168.5.102
diff --git a/host_vars/st0cld0.yml b/host_vars/st0cld0.yml
index 40abf08..45b4f8e 100644
--- a/host_vars/st0cld0.yml
+++ b/host_vars/st0cld0.yml
@@ -1,4 +1,5 @@
-ansible_host: st0cld0
+_groups: openbsd
+
 ip:
   in: 10.10.0.61
   out: 192.168.5.61
diff --git a/host_vars/st0dev0.yml b/host_vars/st0dev0.yml
index 2487ab6..88ddd14 100644
--- a/host_vars/st0dev0.yml
+++ b/host_vars/st0dev0.yml
@@ -1,4 +1,4 @@
-ansible_host: st0dev0
+_groups: openbsd
 ip:
   in: 10.10.0.60
   out: 192.168.5.60
diff --git a/host_vars/st0gme0.yml b/host_vars/st0gme0.yml
index 6db5411..1bdd70d 100644
--- a/host_vars/st0gme0.yml
+++ b/host_vars/st0gme0.yml
@@ -1,4 +1,4 @@
-ansible_host: st0gme0
+_groups: openbsd
 ip:
   in: 10.10.0.62
   out: 192.168.5.62
diff --git a/host_vars/st0gme1.yml b/host_vars/st0gme1.yml
index 8875f68..ad68490 100644
--- a/host_vars/st0gme1.yml
+++ b/host_vars/st0gme1.yml
@@ -1,4 +1,4 @@
-ansible_host: st0gme1
+_groups: alpine
 ip:
   in: 10.10.0.63
   out: 192.168.5.63
diff --git a/host_vars/st0sbx0.yml b/host_vars/st0sbx0.yml
index 09f9c46..e67d1cc 100644
--- a/host_vars/st0sbx0.yml
+++ b/host_vars/st0sbx0.yml
@@ -1,4 +1,4 @@
-ansible_host: st0sbx0
+_groups: openbsd
 ip:
   in: 10.10.0.64
   out: 192.168.5.64
diff --git a/host_vars/st0sbx1.yml b/host_vars/st0sbx1.yml
index 6f71178..c4f692f 100644
--- a/host_vars/st0sbx1.yml
+++ b/host_vars/st0sbx1.yml
@@ -1,4 +1,4 @@
-ansible_host: st0sbx1
+_groups: alpine
 ip:
   in: 10.10.0.65
   out: 192.168.5.65
diff --git a/host_vars/stack0.yml b/host_vars/stack0.yml
index 46afa0d..3c89dd1 100644
--- a/host_vars/stack0.yml
+++ b/host_vars/stack0.yml
@@ -1,4 +1,5 @@
-ansible_host: stack0
+_groups: freebsd
+
 ip:
   in: 10.10.0.40
   out: 192.168.5.40
@@ -20,6 +21,13 @@ vms:
     disks:
       - { id: 0, size: "32G" }
 
+  - name: st0dev1
+    image: openbsd
+    memory: 1G
+    cpu: 1
+    disks:
+      - { id: 0, size: "8G" }
+
   - name: st0cld0
     image: openbsd
     memory: 4G
diff --git a/host_vars/ws-bentonite.yml b/host_vars/ws-bentonite.yml
index d911ba1..755df94 100644
--- a/host_vars/ws-bentonite.yml
+++ b/host_vars/ws-bentonite.yml
@@ -1,4 +1,3 @@
-ansible_host: ws-bentonite
 ip:
   in: 10.10.0.81
   out: 192.168.5.81
diff --git a/host_vars/ws-think01.yml b/host_vars/ws-think01.yml
index 8fab600..724cfb3 100644
--- a/host_vars/ws-think01.yml
+++ b/host_vars/ws-think01.yml
@@ -1,4 +1,3 @@
-ansible_host: ws-think01
 ip:
   in: 10.10.0.82
   out: 192.168.5.82
diff --git a/host_vars/ws-xps01.yml b/host_vars/ws-xps01.yml
index ee09d6b..448ae10 100644
--- a/host_vars/ws-xps01.yml
+++ b/host_vars/ws-xps01.yml
@@ -1,4 +1,3 @@
-ansible_host: ws-xps01
 ip:
   in: 10.10.0.80
   out: 192.168.5.80