Add support for extra_hosts in build config

compose/config/config.py

@@ -1023,6 +1023,7 @@ def to_dict(service):
     md.merge_mapping('args', parse_build_arguments)
     md.merge_field('cache_from', merge_unique_items_lists, default=[])
     md.merge_mapping('labels', parse_labels)
+    md.merge_mapping('extra_hosts', parse_extra_hosts)
     return dict(md)
 
 

compose/config/config_schema_v2.3.json

@@ -92,7 +92,8 @@
                 "cache_from": {"$ref": "#/definitions/list_of_strings"},
                 "network": {"type": "string"},
                 "target": {"type": "string"},
-                "shm_size": {"type": ["integer", "string"]}
+                "shm_size": {"type": ["integer", "string"]},
+                "extra_hosts": {"$ref": "#/definitions/list_or_dict"}
               },
               "additionalProperties": false
             }

compose/service.py

@@ -930,6 +930,7 @@ def build(self, no_cache=False, pull=False, force_rm=False, build_args_override=
             network_mode=build_opts.get('network', None),
             target=build_opts.get('target', None),
             shmsize=parse_bytes(build_opts.get('shm_size')) if build_opts.get('shm_size') else None,
+            extra_hosts=build_opts.get('extra_hosts', None),
         )
 
         try:

tests/integration/service_test.py

@@ -833,6 +833,29 @@ def test_build_with_target(self):
         assert service.image()
         assert service.image()['Config']['Labels']['com.docker.compose.test.target'] == 'one'
 
+    @v2_3_only()
+    def test_build_with_extra_hosts(self):
+        self.require_api_version('1.27')
+        base_dir = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, base_dir)
+
+        with open(os.path.join(base_dir, 'Dockerfile'), 'w') as f:
+            f.write('\n'.join([
+                'FROM busybox',
+                'RUN ping -c1 foobar',
+                'RUN ping -c1 baz',
+            ]))
+
+        service = self.create_service('build_extra_hosts', build={
+            'context': text_type(base_dir),
+            'extra_hosts': {
+                'foobar': '127.0.0.1',
+                'baz': '127.0.0.1'
+            }
+        })
+        service.build()
+        assert service.image()
+
     def test_start_container_stays_unprivileged(self):
         service = self.create_service('web')
         container = create_and_start_container(service).inspect()

tests/unit/service_test.py

@@ -498,6 +498,7 @@ def test_create_container(self):
             network_mode=None,
             target=None,
             shmsize=None,
+            extra_hosts=None,
         )
 
     def test_ensure_image_exists_no_build(self):
@@ -538,7 +539,8 @@ def test_ensure_image_exists_force_build(self):
             cache_from=None,
             network_mode=None,
             target=None,
-            shmsize=None
+            shmsize=None,
+            extra_hosts=None,
         )
 
     def test_build_does_not_pull(self):

tox.ini

@@ -18,7 +18,6 @@ deps =
     -rrequirements-dev.txt
 commands =
     py.test -v \
-        --full-trace \
         --cov=compose \
         --cov-report html \
         --cov-report term \