Source code for ecs_composex.dns.dns_lookup

#  -*- coding: utf-8 -*-
# SPDX-License-Identifier: MPL-2.0
# Copyright 2020-2021 John Mille <john@compose-x.io>

import re

from compose_x_common.compose_x_common import keyisset

from ecs_composex.common import LOG
from ecs_composex.dns.dns_params import ZONES_PATTERN

LAST_DOT_RE = re.compile(r"(\.{1}$)")


[docs]def validate_zone_id_input(zone_id): """ Function to validate the ZoneID is conform to expectations :param str zone_id: :return: True/False :rtype: str """ zones_re = re.compile(ZONES_PATTERN) zones_groups = zones_re.findall(zone_id) if not zones_groups: raise ValueError("ZoneID is not valid. Got", zone_id, "Expected", ZONES_PATTERN) return zones_groups[0]
[docs]def get_all_dns_namespaces(session, namespaces=None, next_token=None): """ Function to recursively fetch all namespaces in account :param list namespaces: :param boto3.session.Session session: :param str next_token: :return: """ if namespaces is None: namespaces = [] filters = [{"Name": "TYPE", "Values": ["DNS_PRIVATE"], "Condition": "EQ"}] client = session.client("servicediscovery") if not next_token: namespaces_r = client.list_namespaces(Filters=filters) else: namespaces_r = client.list_namespaces(Filters=filters, NextToken=next_token) namespaces += namespaces_r["Namespaces"] if "NextToken" in namespaces_r: return get_all_dns_namespaces(session, namespaces, namespaces_r["NextToken"]) return namespaces
[docs]def lookup_service_discovery_namespace(zone, session, private): client = session.client("servicediscovery") try: namespaces = get_all_dns_namespaces(session) if zone.name not in [z["Name"] for z in namespaces]: raise LookupError("No private namespace found for zone", zone.name) the_zone = None for l_zone in namespaces: if zone.name == l_zone["Name"]: the_zone = l_zone zone_r = client.get_namespace(Id=the_zone["Id"]) properties = zone_r["Namespace"]["Properties"] if zone_r["Namespace"]["Type"] == "HTTP": raise TypeError( "Unsupported CloudMap namespace HTTP. " "Only DNS namespaces, private or public, are supported" ) return { "Route53ID": properties["DnsProperties"]["HostedZoneId"], "ZoneTld": LAST_DOT_RE.sub("", properties["HttpProperties"]["HttpName"]), "ZoneId": zone_r["Namespace"]["Id"], } except client.exceptions.NamespaceNotFound: LOG.error(f"Namespace not found for {zone.name}") raise except client.exceptions.InvalidInput: LOG.error("Failed to retrieve the zone info") raise
[docs]def filter_out_cloudmap_zones(zones, zone_name): """ Function to filter out the Hosted Zones linked to CloudMap :param list zones: :return: The only valid zone :rtype: dict """ new_zones = [] for zone in zones: if ( keyisset("LinkedService", zone) and keyisset("ServicePrincipal", zone["LinkedService"]) and zone["LinkedService"]["ServicePrincipal"] == "servicediscovery.amazonaws.com" ): continue else: new_zones.append(zone) if not zone_name.endswith("."): zone_name = f"{zone_name}." if not new_zones or not new_zones[0]["Name"] == zone_name: raise LookupError( "The first zone found does not match the DNS zone we are looking for." "As per API definition, this means the zone was not found", new_zones, ) return new_zones[0]
[docs]def lookup_route53_namespace(zone, session, private): client = session.client("route53") try: zones_req = client.list_hosted_zones_by_name(DNSName=zone.name)["HostedZones"] zones_r = filter_out_cloudmap_zones(zones_req, zone.name) zone_r = client.get_hosted_zone(Id=zones_r["Id"])["HostedZone"] if zone_r["Config"]["PrivateZone"] != private: raise ValueError(f"The zone {zone.name} is not a private zone.") return { "ZoneId": zone_r["Id"].split(r"/")[-1], "ZoneTld": LAST_DOT_RE.sub("", zone_r["Name"]), } except client.exceptions.InvalidDomainName: LOG.warning(f"Zone {zone.name} is invalid or malformed.")
[docs]def lookup_namespace(zone, session): """ Function to find the namespace infos :param ecs_composex.dns.DnsZone zone: :param boto3.session.Session session: boto3 session to make API call :return: """ zone_info = None if zone.key == "PrivateNamespace": zone_info = lookup_service_discovery_namespace(zone, session, private=True) elif zone.key == "PublicZone": zone_info = lookup_route53_namespace(zone, session, private=False) return zone_info