Added ability to specify Docker build stage (fixes #329) (#330)

* added build_stage to BuildInstructions

* extract build stage

* specify build stage

* updated version

* updated docs

* bug fix: stage -> target

CHANGELOG.md

@@ -1,3 +1,10 @@
+## 2.1.27 (2019-05-08)
+
+### Features
+
+* Added ability to specify a particular Docker build stage.
+
+
 ## 2.1.26 (2019-03-14)
 
 ### Bug Fixes

bugzoo/core/build.py

@@ -53,6 +53,12 @@ class BuildInstructions(object):
     """
     depends_on = attr.ib(type=Optional[str])
 
+    """
+    The name of the build stage, if any, that should be used when building this
+    image.
+    """
+    build_stage = attr.ib(type=Optional[str], default=None)
+
     @property
     def name(self) -> str:
         return self.tag

bugzoo/mgr/build.py

@@ -114,6 +114,7 @@ def build(self,
                                                tag=name,
                                                # pull=force,
                                                buildargs=instructions.arguments,
+                                               target=instructions.build_stage,
                                                decode=True,
                                                rm=True)
 

bugzoo/mgr/source.py

@@ -165,6 +165,7 @@ def __parse_blueprint(self, source: Source, fn: str, d: dict) -> BuildInstructio
                                  filename=d.get('file', 'Dockerfile'),
                                  arguments=d.get('arguments', {}),
                                  source=source.name,
+                                 build_stage=d.get('build-stage', None),
                                  depends_on=d.get('depends-on', None))
 
     def __parse_bug(self, source: Source, fn: str, d: dict) -> Bug:

bugzoo/version.py

@@ -1 +1 @@
-__version__ = '2.1.26'
+__version__ = '2.1.27'

docs/file-format.rst

@@ -68,6 +68,8 @@ Below, we discuss each of the properties used to describe a blueprint:
   image.
 * The :code:`depends-on` property optionally specifies the name of the Docker
   image, if any, that the Docker image described by the blueprint relies on.
+* The :code:`build-stage` property optionally specifies the name of the Docker
+  build stage that should be used to construct the image.
 
 Bugs
 ----