Add dev mode install playbook for source installs

The following playbook will produce a modified image with Python source
code installed via pip. To minimize dependencies within the container
we generate the sdist locally and then copy it into the resulting
container image as an sdist tarball to run pip install locally.

Useful for local ad-hoc testing of upstream patches without
having to build and RPM in those cases.

Change-Id: I93c0e86b2e421b0bcb777d536fcb0d30e0ee3b68

README.md

@@ -26,6 +26,18 @@ A role to allow modification to container images built for the TripleO project.
 | `yum_repos_dir_path` | `None` | Optional path of directory to be used as `/etc/yum.repos.d` during the update |
 | `container_build_tool` | `docker` | See modify image variables |
 
+
+**Variables used for dev install**
+
+| Name              | Default Value       | Description          |
+|-------------------|---------------------|----------------------|
+| `source_image` | `[undefined]` | See modify image variables |
+| `modified_append_tag` | `date +-modified-%Y%m%d%H%M%S` | See modify image variables |
+| `target_image` | `''` | See modify image variables |
+| `container_build_tool` | `docker` | See modify image variables |
+| `refspecs` | `[]` | An array of project/refspec pairs that will be installed into the generated container. Currently only supports python source projects. |
+
+
 ## Requirements ##
 
  - ansible >= 2.4
@@ -112,6 +124,28 @@ network connectivity.
           rpms_path: /foo/bar
           modified_append_tag: -hotfix
 
+### Dev install ###
+
+The following playbook will produce a modified image with Python source
+code installed via pip. To minimize dependencies within the container
+we generate the sdist locally and then copy it into the resulting
+container image as an sdist tarball to run pip install locally.
+
+    - hosts: localhost
+      connection: local
+      tasks:
+      - name: dev install heat-api
+        import_role:
+          name: tripleo-modify-image
+        vars:
+          tasks_from: dev_install.yml
+          source_image: docker.io/tripleomaster/centos-binary-heat-api:current-tripleo
+          refspecs:
+            -
+              project: heat
+              refspec: refs/changes/12/1234/3
+          modified_append_tag: -devel
+
 ## License ##
 
 Apache 2.0

files/dev_install.sh

@@ -0,0 +1,32 @@
+set -e
+
+# Cherry-pick a refspec
+# $1 : project name e.g. keystone
+# $2 : Gerrit refspec(s) to cherry pick
+function cherrypick(){
+    local PROJ_NAME=$1
+    local REFSPECS="$2"
+
+    # check that git is installed
+    if ! rpm -qi git &> /dev/null; then
+        echo "Please install git before using this module."
+        exit 1
+    fi
+
+    if [ ! -d "$PROJ_NAME" ]; then
+        git clone "https://git.openstack.org/openstack/$PROJ_NAME"
+    fi
+    cd "$PROJ_NAME"
+    for REFSPEC in $REFSPECS; do
+        git fetch "https://review.openstack.org/openstack/$PROJ_NAME" "$REFSPEC"
+        git cherry-pick FETCH_HEAD || git cherry-pick --abort
+    done
+
+    SKIP_GENERATE_AUTHORS=1 SKIP_WRITE_GIT_CHANGELOG=1 python setup.py sdist
+    cp dist/*.tar.gz ../
+
+}
+
+mkdir -p refspec_projects
+cd refspec_projects
+cherrypick $1 $2

tasks/dev_install.yml

@@ -0,0 +1,34 @@
+- import_tasks: precheck.yml
+  tags:
+    - always
+
+- import_tasks: get_original_user.yml
+
+- name: Create image build context directory
+  tempfile:
+    state: directory
+    prefix: tripleo-modify-image
+  register: context_dir
+
+- name: Set modify_dir_path
+  set_fact:
+    modify_dir_path: "{{ context_dir.path }}"
+
+- name: Write Dockerfile to {{ modify_dir_path }}
+  template:
+    src: Dockerfile-dev.j2
+    dest: "{{ modify_dir_path }}/Dockerfile"
+
+- name: Write dev_install.sh
+  copy:
+    src: dev_install.sh
+    dest: "{{ modify_dir_path }}/dev_install.sh"
+    mode: '0555'
+
+- name: Git checkout the refspecs into local temp dir
+  command: "/bin/bash dev_install.sh {{ item.project }} {{ item.refspec }}"
+  args:
+    chdir: "{{ modify_dir_path }}"
+  loop: "{{ refspecs }}"
+
+- include_tasks: modify_image.yml

templates/Dockerfile-dev.j2

@@ -0,0 +1,9 @@
+FROM {{ source_image }}
+LABEL modified_append_tag={{ modified_append_tag }}
+
+USER root
+
+COPY refspec_projects /root/refspec_projects
+RUN /bin/bash -c 'rpm -qi python-pip || yum install -y python-pip; cd /; for X in $(ls /root/refspec_projects/*.tar.gz); do pip install $X; done; rm -Rf /root/refspec_projects'
+
+USER "{{ original_user }}"