Build args (#16)

* Build args docs

* Small fix

source/pages/pipelines/building_template.rst

@@ -13,6 +13,7 @@ Currently the fields supporting interpolations are:
   - :attr:`ContainerBuild<ContainerBuild>`:
 
     - ``tags``
+    - ``buildArgs``
 
   - :attr:`ServiceRun<ServiceRun>`:
 
@@ -34,10 +35,13 @@ Here are examples of using interpolation to create a Docker tag containing the n
       tags:
       - "build-{{ ICECI_BUILD_NUMBER }}"
       - latest
+      buildArgs:
+      - name: BRANCH
+        value: "{{ ICECI_GIT_BRANCH_NAME }}"
   - name: pipeline-service
     serviceRun:
       name: example-service
-      image: "myapp:build-{{ ICE_BUILD_NUMBER }}"
+      image: "myapp:build-{{ ICECI_BUILD_NUMBER }}"
       dockerSecret: dockerhub
 
 

source/pages/pipelines/structure.rst

@@ -225,6 +225,11 @@ Definitions of all objects and types used in the pipeline definition.
 
     Name of the Docker secret used for communicating with Docker registry. Used for pulling image from private registries.
 
+  .. py:data:: buildArgs
+    :type: list(BuildArg)
+
+    A list of build-time arguments.
+
 
 .. py:attribute:: ServiceRun
   :type: Object
@@ -390,6 +395,20 @@ Definitions of all objects and types used in the pipeline definition.
     Name of a secret from which the value should be retrieved to mount into the container as a file.
 
 
+.. py:attribute:: BuildArg
+  :type: Object
+
+  The BuildArg object represents a build-time parameter that will be set during the build. Equivalent to ``--build-arg`` parameter in the ``docker build`` command.
+
+  .. py:attribute:: name
+
+    The name of the build argument
+
+  ..  py:attribute:: value
+
+    The value of the build argument
+
+
 .. py:attribute:: When
   :type: Object