Implement APIGateway get_base_path_mapping (#4531)

moto/apigateway/exceptions.py

@@ -265,3 +265,12 @@ class BasePathConflictException(ConflictException):
         super(BasePathConflictException, self).__init__(
             "ConflictException", "Base path already exists for this domain name"
         )
+
+
+class BasePathNotFoundException(NotFoundException):
+    code = 404
+
+    def __init__(self):
+        super(BasePathNotFoundException, self).__init__(
+            "NotFoundException", "Invalid base path mapping identifier specified"
+        )

moto/apigateway/models.py

@@ -47,6 +47,7 @@ from .exceptions import (
     InvalidRestApiIdForBasePathMappingException,
     InvalidStageException,
     BasePathConflictException,
+    BasePathNotFoundException,
 )
 from ..core.models import responses_mock
 from moto.apigateway.exceptions import MethodNotFoundException
@@ -1769,6 +1770,16 @@ class APIGatewayBackend(BaseBackend):
 
         return list(self.base_path_mappings[domain_name].values())
 
+    def get_base_path_mapping(self, domain_name, base_path):
+
+        if domain_name not in self.domain_names:
+            raise DomainNameNotFound()
+
+        if base_path not in self.base_path_mappings[domain_name]:
+            raise BasePathNotFoundException()
+
+        return self.base_path_mappings[domain_name][base_path]
+
 
 apigateway_backends = {}
 for region_name in Session().get_available_regions("apigateway"):

moto/apigateway/responses.py

@@ -1,4 +1,5 @@
 import json
+from urllib.parse import unquote
 
 from moto.utilities.utils import merge_multiple_dicts
 from moto.core.responses import BaseResponse
@@ -876,3 +877,23 @@ class APIGatewayResponse(BaseResponse):
             return self.error("NotFoundException", e.message, 404)
         except ConflictException as e:
             return self.error("ConflictException", e.message, 409)
+
+    def base_path_mapping_individual(self, request, full_url, headers):
+
+        self.setup_class(request, full_url, headers)
+
+        url_path_parts = self.path.split("/")
+        domain_name = url_path_parts[2]
+        base_path = unquote(url_path_parts[4])
+
+        try:
+            if self.method == "GET":
+                base_path_mapping = self.backend.get_base_path_mapping(
+                    domain_name, base_path
+                )
+                return 200, {}, json.dumps(base_path_mapping)
+            elif self.method == "DELETE":
+                # TODO Implements
+                pass
+        except NotFoundException as e:
+            return self.error("NotFoundException", e.message, 404)

moto/apigateway/urls.py

@@ -28,6 +28,7 @@ url_paths = {
     "{0}/restapis/(?P<function_id>[^/]+)/models/(?P<model_name>[^/]+)/?$": response.model_induvidual,
     "{0}/domainnames/(?P<domain_name>[^/]+)/?$": response.domain_name_induvidual,
     "{0}/domainnames/(?P<domain_name>[^/]+)/basepathmappings$": response.base_path_mappings,
+    "{0}/domainnames/(?P<domain_name>[^/]+)/basepathmappings/(?P<base_path_mapping>[^/]+)$": response.base_path_mapping_individual,
     "{0}/usageplans/(?P<usage_plan_id>[^/]+)/?$": response.usage_plan_individual,
     "{0}/usageplans/(?P<usage_plan_id>[^/]+)/keys$": response.usage_plan_keys,
     "{0}/usageplans/(?P<usage_plan_id>[^/]+)/keys/(?P<api_key_id>[^/]+)/?$": response.usage_plan_key_individual,

tests/test_apigateway/test_apigateway.py

@@ -2559,3 +2559,71 @@ def test_get_base_path_mappings_with_unknown_domain():
     )
     ex.value.response["Error"]["Code"].should.equal("NotFoundException")
     ex.value.response["ResponseMetadata"]["HTTPStatusCode"].should.equal(404)
+
+
+@mock_apigateway
+def test_get_base_path_mapping():
+    client = boto3.client("apigateway", region_name="us-west-2")
+    domain_name = "testDomain"
+    test_certificate_name = "test.certificate"
+    client.create_domain_name(
+        domainName=domain_name, certificateName=test_certificate_name
+    )
+
+    response = client.create_rest_api(name="my_api", description="this is my api")
+    api_id = response["id"]
+
+    stage_name = "dev"
+    create_method_integration(client, api_id)
+    client.create_deployment(
+        restApiId=api_id, stageName=stage_name, description="1.0.1"
+    )
+
+    client.create_base_path_mapping(
+        domainName=domain_name, restApiId=api_id, stage=stage_name
+    )
+
+    response = client.get_base_path_mapping(domainName=domain_name, basePath="(none)")
+    response["ResponseMetadata"]["HTTPStatusCode"].should.equal(200)
+    response["basePath"].should.equal("(none)")
+    response["restApiId"].should.equal(api_id)
+    response["stage"].should.equal(stage_name)
+
+
+@mock_apigateway
+def test_get_base_path_mapping_with_unknown_domain():
+    client = boto3.client("apigateway", region_name="us-west-2")
+
+    with pytest.raises(ClientError) as ex:
+        client.get_base_path_mapping(domainName="unknown-domain", basePath="v1")
+
+    ex.value.response["Error"]["Message"].should.equal(
+        "Invalid domain name identifier specified"
+    )
+    ex.value.response["Error"]["Code"].should.equal("NotFoundException")
+    ex.value.response["ResponseMetadata"]["HTTPStatusCode"].should.equal(404)
+
+
+@mock_apigateway
+def test_get_base_path_mapping_with_unknown_base_path():
+    client = boto3.client("apigateway", region_name="us-west-2")
+    domain_name = "testDomain"
+    test_certificate_name = "test.certificate"
+    client.create_domain_name(
+        domainName=domain_name, certificateName=test_certificate_name
+    )
+
+    response = client.create_rest_api(name="my_api", description="this is my api")
+    api_id = response["id"]
+    client.create_base_path_mapping(
+        domainName=domain_name, restApiId=api_id, basePath="v1"
+    )
+
+    with pytest.raises(ClientError) as ex:
+        client.get_base_path_mapping(domainName=domain_name, basePath="unknown")
+
+    ex.value.response["Error"]["Message"].should.equal(
+        "Invalid base path mapping identifier specified"
+    )
+    ex.value.response["Error"]["Code"].should.equal("NotFoundException")
+    ex.value.response["ResponseMetadata"]["HTTPStatusCode"].should.equal(404)