From 6ff519aecd49d7991a30086c8001bb96aa68dbff Mon Sep 17 00:00:00 2001
From: "Dustin C. Hatch" <dustin@hatch.name>
Date: Sun, 7 Aug 2022 10:36:18 -0500
Subject: [PATCH] Initial commit

---
 .gitignore                   |  1 +
 Config.in                    |  0
 README.md                    | 42 ++++++++++++++++++++++++++++++++++++
 configs/pythonctnr_defconfig | 14 ++++++++++++
 external.desc                |  2 ++
 external.mk                  |  0
 6 files changed, 59 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 Config.in
 create mode 100644 README.md
 create mode 100644 configs/pythonctnr_defconfig
 create mode 100644 external.desc
 create mode 100644 external.mk

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ba65b13
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/_build/
diff --git a/Config.in b/Config.in
new file mode 100644
index 0000000..e69de29
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..04bef10
--- /dev/null
+++ b/README.md
@@ -0,0 +1,42 @@
+# Minimal Base Python Container Image
+
+The *pythonctnr* image contains ONLY the Python runtime, and nothing else.  It
+is suitable for deploying applications written in pure Python, without any
+external library dependencies.  No shell or other OS utilities are included.
+Just `/usr/bin/python3` and the libraries it needs to run.
+
+
+## Building
+
+The contents of the container image are built with [buildroot][0].
+
+```sh
+make -C ~/src/buildroot O=${PWD}/_build pythonctnr_defconfig
+make -C _build
+```
+
+This will produce a `rootfs.tar` tarball in `_build/images`, which is then
+converted to a container image using `buildah`.
+
+```sh
+ctnr=$(buildah from scratch)
+buildah add ${ctnr} _build/images/rootfs.tar /
+buildah commit ${ctnr} pythonctnr:latest
+```
+
+[0]: https://buildroot.org/
+
+
+## Usage
+
+The container image can be used like any other image, e.g. in a `Dockerfile`.
+*pip* is included, to allow installing Python distribution packages.
+
+```Dockerfile
+FROM pythonctnr
+
+RUN ["/usr/bin/python3", "-m", "pip", "install", "mypkg"]
+```
+
+**NOTE**: Because there is no shell, the default string form of the `RUN`
+instruction does not work.  You must use the *exec* form.
diff --git a/configs/pythonctnr_defconfig b/configs/pythonctnr_defconfig
new file mode 100644
index 0000000..aca678d
--- /dev/null
+++ b/configs/pythonctnr_defconfig
@@ -0,0 +1,14 @@
+BR2_x86_64=y
+BR2_TOOLCHAIN_BUILDROOT_GLIBC=y
+BR2_TARGET_GENERIC_HOSTNAME="pythonctnr"
+BR2_TARGET_GENERIC_ISSUE=""
+BR2_INIT_NONE=y
+BR2_ROOTFS_MERGED_USR=y
+# BR2_TARGET_ENABLE_ROOT_LOGIN is not set
+BR2_SYSTEM_BIN_SH_NONE=y
+# BR2_TARGET_GENERIC_GETTY is not set
+# BR2_TARGET_GENERIC_REMOUNT_ROOTFS_RW is not set
+BR2_SYSTEM_DEFAULT_PATH="/bin:/sbin:/usr/bin:/usr/sbin"
+# BR2_PACKAGE_BUSYBOX is not set
+BR2_PACKAGE_PYTHON3=y
+BR2_PACKAGE_PYTHON_PIP=y
diff --git a/external.desc b/external.desc
new file mode 100644
index 0000000..7d5a4da
--- /dev/null
+++ b/external.desc
@@ -0,0 +1,2 @@
+name: pythonctnr
+desc: Python container image
diff --git a/external.mk b/external.mk
new file mode 100644
index 0000000..e69de29