[re2o_lookup] Make use of cache.

ansible.cfg

@@ -45,3 +45,10 @@ api_hostname = intranet.crans.org
 
 # Whether or not using vault_cranspasswords
 use_cpasswords = True
+
+# Specify cache plugin for re2o API. By default, cache nothing
+cache = jsonfile
+
+# Time in second before the cache expired. 0 means never expire cache.
+# Default is 120 seconds.
+timeout = 120

lookup_plugins/re2oapi.py

@@ -7,6 +7,8 @@ For a detailed example look at https://github.com/ansible/ansible/blob/3dbf89e8a
 The API Client has been adapted from https://gitlab.federez.net/re2o/re2oapi
 """
 
+from ansible.plugins.loader import cache_loader
+
 from pathlib import Path
 import datetime
 import requests
@@ -340,6 +342,73 @@ class LookupModule(LookupBase):
         - debug: var=dnszones
     """
 
+    def _readconfig(self, section="re2o", key=None, boolean=False,
+                    integer=False):
+        config = self._config
+        if not config:
+            return None
+        else:
+            if config.has_option(section, key):
+                display.vvv("Found key {} in configuration file".format(key))
+                if boolean:
+                    return config.getboolean(section, key)
+                elif integer:
+                    return config.getint(section, key)
+                else:
+                    return config.get(section, key)
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        config_manager = ConfigManager()
+        config_file = config_manager.data.get_setting(name="CONFIG_FILE").value
+        self._config = ConfigParser()
+        self._config.read(config_file)
+
+        display.vvv("Using {} as configuration file.".format(config_file))
+
+        self._api_hostname = None
+        self._api_username = None
+        self._api_password = None
+        self._use_cpasswords = None
+        self._cache_plugin = None
+        self._cache = None
+        self._timeout = 120
+
+        if self._config.has_section("re2o"):
+            display.vvv("Found section re2o in configuration file")
+
+            self._api_hostname = self._readconfig(key="api_hostname")
+            self._use_cpasswords = self._readconfig(key="use_cpasswords",
+                                                    boolean=True)
+            self._cache_plugin = self._readconfig(key="cache")
+            self._timeout = self._readconfig(key="timeout", integer=True)
+
+        if self._cache_plugin is not None:
+            display.vvv("Using {} as cache plugin".format(self._cache_plugin))
+
+            if self._cache_plugin == 'jsonfile':
+                self._cachedir = Path.home() / ".cache/Ansible/re2oapi"
+                display.vvv("Cache directory is {}".format(self._cachedir))
+                if not self._cachedir.exists():
+                    # Creates Ansible cache directory with right permissions
+                    # if it doesn't exist yet.
+                    display.vvv("Cache directory doesn't exist. Creating it.")
+                    try:
+                        self._cachedir.mkdir(mode=0o700, parents=True)
+                    except Exception as e:
+                        raise AnsibleError("""Unable to create {dir}.
+                        Original error was : {err}"""
+                                           .format(dir=self._cachedir,
+                                                   err=to_native(e)))
+                self._cache = cache_loader.get('jsonfile',
+                                               _uri=self._cachedir,
+                                               _timeout=self._timeout,
+                                               )
+            else:
+                raise AnsibleError("Cache plugin {} not supported"
+                                   .format(self._cache_plugin))
+
     def run(self, terms, variables=None, api_hostname=None, api_username=None,
             api_password=None, use_tls=True):
 
@@ -354,33 +423,20 @@ class LookupModule(LookupBase):
            :returns: A list of results to the specific queries.
         """
 
-        config_manager = ConfigManager()
+        # Use the hostname specified by the user if it exists.
-        config_file = config_manager.data.get_setting(name="CONFIG_FILE").value
+        if api_hostname is not None:
-        config = ConfigParser()
+            display.vvv("Overriding api_hostname with {}".format(api_hostname))
-        config.read(config_file)
+        else:
+            api_hostname = self._api_hostname
 
-        use_cpasswords = False
+        if self._api_hostname is None:
-
-        if config.has_section("re2o"):
-            display.vvv("Found section re2o in configuration file")
-            if config.has_option("re2o", "api_hostname"):
-                display.vvv("Found option api_hostname in config file")
-                api_hostname = config.get("re2o", "api_hostname")
-                display.vvv("Override api_hostname with {} from configuration"
-                            .format(api_hostname))
-            if config.has_option("re2o", "use_cpasswords"):
-                display.vvv("Found option use_cpasswords in config file")
-                use_cpasswords = config.getboolean("re2o", "use_cpasswords")
-                display.vvv("Override api_hostname with {} from configuration"
-                            .format(use_cpasswords))
-
-        if api_hostname is None:
             raise AnsibleError(to_native(
                 'You must specify a hostname to contact re2oAPI'
             ))
 
-        if api_username is None and api_password is None and use_cpasswords:
+        if (api_username is None and api_password is None
-            display.vvv("Use cpasswords vault to get API credentials.")
+                and self._use_cpasswords):
+            display.vvv("Using cpasswords vault to get API credentials.")
             api_username = variables.get('vault_re2o_service_user')
             api_password = variables.get('vault_re2o_service_password')
 
@@ -399,7 +455,7 @@ class LookupModule(LookupBase):
 
         res = []
         dterms = collections.deque(terms)
-        machines_roles = None  # TODO : Cache this.
+
         display.vvv("Lookup terms are {}".format(terms))
         while dterms:
             term = dterms.popleft()
@@ -411,10 +467,7 @@ class LookupModule(LookupBase):
             elif term == 'get_role':
                 try:
                     role_name = dterms.popleft()
-                    roles, machines_roles = self._get_role(api_client,
+                    roles = self._get_role(api_client, role_name)
-                                                           role_name,
-                                                           machines_roles,
-                                                           )
                     res.append(roles)
                 except IndexError:
                     display.v("Error in re2oapi : No role_name provided")
@@ -429,17 +482,72 @@ class LookupModule(LookupBase):
                                        .format(to_native(e)))
         return res
 
+    def _get_cache(self, key):
+        if self._cache:
+            return self._cache.get(key)
+        else:
+            return None
+
+    def _set_cache(self, key, value):
+        if self._cache:
+            return self._cache.set(key, value)
+        else:
+            return None
+
+    def _is_cached(self, key):
+        if self._cache:
+            return self._cache.contains(key)
+        else:
+            return False
+
     def _getzones(self, api_client):
         display.v("Getting dns zone names")
+        zones, zones_name = None, None
+
+        if self._is_cached('dnszones'):
+            zones_name = self._get_cache('dnszones')
+
+        if zones_name is not None:
+            display.vvv("Found dnszones in cache.")
+
+        else:
+            if self._is_cached('dns_zones'):
+                zones = self._get_cache('dns_zones')
+            if zones is not None:
+                display.vvv("Found dns/zones in cache.")
+            else:
+                display.vvv("Contacting the API, endpoint dns/zones...")
                 zones = api_client.list('dns/zones')
+                display.vvv("...Done")
             zones_name = [zone["name"][1:] for zone in zones]
+            display.vvv("Storing dnszones in cache.")
+            self._set_cache('dnszones', zones_name)
+
         return zones_name
 
     def _getreverse(self, api_client):
         display.v("Getting dns reverse zones")
-        display.vvv("Contacting the API, endpoint dns/reverse-zones...")
+
+        zones, res = None, None
+
+        if self._is_cached('dnsreverse'):
+            res = self._get_cache('dnsreverse')
+
+        if res is not None:
+            display.vvv("Found dnsreverse in cache.")
+
+        else:
+            if self._is_cached('dns_reverse-zones'):
+                zones = self._get_cache('dns_reverse-zones')
+
+            if zones is not None:
+                display.vvv("Found dns/reverse-zones in cache.")
+            else:
+                display.vvv("Contacting the API, endpoint dns/reverse-zones..")
                 zones = api_client.list('dns/reverse-zones')
                 display.vvv("...Done")
+
+            display.vvv("Trying to format dns reverse in a nice way.")
             res = []
             for zone in zones:
                 if zone['ptr_records']:
@@ -455,6 +563,7 @@ class LookupModule(LookupBase):
                             subnets.extend(net.subnet(16))
                         else:
                             subnets.extend(net.subnet(8))
+
                     for subnet in subnets:
                         _address = netaddr.IPAddress(subnet.first)
                         rev_dns_a = _address.reverse_dns.split('.')[:-1]
@@ -466,22 +575,60 @@ class LookupModule(LookupBase):
                             zone_name = '.'.join(rev_dns_a[1:])
                         res.append(zone_name)
                         display.vvv("Found reverse zone {}".format(zone_name))
+
                 if zone['ptr_v6_records']:
                     display.vvv("Found PTR v6 record")
-                    net = netaddr.IPNetwork(zone['prefix_v6']+'/'+str(zone['prefix_v6_length']))
+                    net = netaddr.IPNetwork(zone['prefix_v6']
+                                            + '/'
+                                            + str(zone['prefix_v6_length']))
                     net_class = max(((net.prefixlen - 1) // 4) + 1, 1)
                     zone6_name = ".".join(
-                        netaddr.IPAddress(net.first).reverse_dns.split('.')[32 - net_class:])[:-1]
+                        netaddr.IPAddress(net.first)
+                        .reverse_dns.split('.')[32 - net_class:])[:-1]
                     res.append(zone6_name)
                     display.vvv("Found reverse zone {}".format(zone6_name))
-        return list(set(res))
+
+            display.vvv("Storing dns reverse zones in cache.")
+            self._set_cache('dnsreverse', list(set(res)))
+
+        return res
 
     def _rawquery(self, api_client, endpoint):
-        display.v("Make a raw query to endpoint {}".format(endpoint))
+        res = None
-        return api_client.list(endpoint)
+        if self._is_cached(endpoint.replace('/', '_')):
+            res = self._get_cache(endpoint.replace('/', '_'))
+        if res is not None:
+            display.vvv("Found {} in cache.".format(endpoint))
+        else:
+            display.v("Making a raw query {host}/api/{endpoint}"
+                      .format(host=self.api_hostname, endpoint=endpoint))
+            res = api_client.list(endpoint)
+            display.vvv("Storing result in cache.")
+            self._set_cache(endpoint.replace('/', '_'), res)
+        return res
 
-    def _get_role(self, api_client, role_name, machines_roles):
+    def _get_role(self, api_client, role_name):
-        if machines_roles is None:
+        res, machines_roles = None, None
+
+        if self._is_cached(role_name):
+            res = self._get_cache(role_name)
+
+        if res is not None:
+            display.vvv("Found {} in cache.".format(role_name))
+        else:
+            if self._is_cached("machines_role"):
+                machines_roles = self._get_cache("machines_role")
+
+            if machines_roles is not None:
+                display.vvv("Found machines/roles in cache.")
+            else:
                 machines_roles = api_client.list("machines/role")
-        return list(filter(lambda machine: machine["role_type"] == role_name,
+                display.vvv("Storing machines/role in cache.")
-                           machines_roles)), machines_roles
+                self._set_cache("machines_role", machines_roles)
+
+            res = list(filter(lambda m: m["role_type"] == role_name,
+                              machines_roles))
+            display.vvv("Storing {} in cache.".format(role_name))
+            self._set_cache(role_name, res)
+
+        return res