[PATCH v1] dts: add Dockerfile

["Juraj Linkeš" <juraj.linkes@pantheon.tech>]

The Dockerfile defines development and CI runner images.

Signed-off-by: Juraj Linkeš <juraj.linkes@pantheon.tech>
---
 dts/.devcontainer/devcontainer.json | 30 ++++++++++++++++
 dts/Dockerfile                      | 38 ++++++++++++++++++++
 dts/README.md                       | 55 +++++++++++++++++++++++++++++
 3 files changed, 123 insertions(+)
 create mode 100644 dts/.devcontainer/devcontainer.json
 create mode 100644 dts/Dockerfile
 create mode 100644 dts/README.md

diff --git a/dts/.devcontainer/devcontainer.json b/dts/.devcontainer/devcontainer.json
new file mode 100644
index 0000000000..41ca28fc17
--- /dev/null
+++ b/dts/.devcontainer/devcontainer.json
@@ -0,0 +1,30 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the README at:
+// https://github.com/microsoft/vscode-dev-containers/tree/v0.241.1/containers/docker-existing-dockerfile
+{
+	"name": "Existing Dockerfile",
+
+	// Sets the run context to one level up instead of the .devcontainer folder.
+	"context": "..",
+
+	// Update the 'dockerFile' property if you aren't using the standard 'Dockerfile' filename.
+	"dockerFile": "../Dockerfile",
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Uncomment the next line to run commands after the container is created - for example installing curl.
+	"postCreateCommand": "poetry install",
+
+	"extensions": [
+		"ms-python.vscode-pylance",
+	]
+
+	// Uncomment when using a ptrace-based debugger like C++, Go, and Rust
+	// "runArgs": [ "--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined" ],
+
+	// Uncomment to use the Docker CLI from inside the container. See https://aka.ms/vscode-remote/samples/docker-from-docker.
+	// "mounts": [ "source=/var/run/docker.sock,target=/var/run/docker.sock,type=bind" ],
+
+	// Uncomment to connect as a non-root user if you've added one. See https://aka.ms/vscode-remote/containers/non-root.
+	// "remoteUser": "vscode"
+}
diff --git a/dts/Dockerfile b/dts/Dockerfile
new file mode 100644
index 0000000000..9a91949eeb
--- /dev/null
+++ b/dts/Dockerfile
@@ -0,0 +1,38 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2022 University of New Hampshire
+
+# There are two Docker images defined in this Dockerfile.
+# One is to be used in CI for automated testing.
+# The other provides a DTS development environment, simplifying Python dependency management.
+
+FROM ubuntu:22.04 AS base
+
+RUN apt-get -y update && apt-get -y upgrade && \
+    apt-get -y install --no-install-recommends \
+        python3 \
+        python3-pip \
+        python3-pexpect \
+        python3-poetry \
+        python3-cachecontrol \
+        openssh-client
+WORKDIR /dpdk/dts
+
+
+FROM base AS runner
+
+# This image is intended to be used as the base for automated systems.
+# It bakes DTS into the image during the build.
+
+COPY . /dpdk/dts
+RUN poetry install --no-dev
+
+CMD ["poetry", "run", "python", "main.py"]
+
+FROM base AS dev
+
+# This image is intended to be used as DTS development environment. It doesn't need C compilation
+# capabilities, only Python dependencies. Once a container mounting DTS using this image is running,
+# the dependencies should be installed using Poetry.
+
+RUN apt-get -y install --no-install-recommends \
+        vim emacs git
diff --git a/dts/README.md b/dts/README.md
new file mode 100644
index 0000000000..fd9f32595c
--- /dev/null
+++ b/dts/README.md
@@ -0,0 +1,55 @@
+# DTS Environment
+The execution and development environments for DTS are the same, a
+[Docker](https://docs.docker.com/) container defined by our [Dockerfile](./Dockerfile).
+Using a container for the development environment helps with a few things.
+
+1. It helps enforce the boundary between the DTS environment and the TG/SUT, something
+   which caused issues in the past.
+2. It makes creating containers to run DTS inside automated tooling much easier, since
+   they can be based off of a known-working environment that will be updated as DTS is.
+3. It abstracts DTS from the server it is running on. This means that the bare-metal os
+   can be whatever corporate policy or your personal preferences dictate, and DTS does
+   not have to try to support all distros that are supported by DPDK CI.
+4. It makes automated testing for DTS easier, since new dependencies can be sent in with
+  the patches.
+5. It fixes the issue of undocumented dependencies, where some test suites require
+   python libraries that are not installed.
+6. Allows everyone to use the same python version easily, even if they are using a
+   distribution or Windows with out-of-date packages.
+7. Allows you to run the tester on Windows while developing via Docker for Windows.
+
+## Tips for setting up a development environment
+
+### Getting a docker shell
+These commands will give you a bash shell inside the container with all the python
+dependencies installed. This will place you inside a python virtual environment. DTS is
+mounted via a volume, which is essentially a symlink from the host to the container.
+This enables you to edit and run inside the container and then delete the container when
+you are done, keeping your work.
+
+```shell
+docker build --target dev -t dpdk-dts .
+docker run -v $(pwd)/..:/dpdk -it dpdk-dts bash
+$ poetry install
+$ poetry shell
+```
+
+### Vim/Emacs
+Any editor in the ubuntu repos should be easy to use, with vim and emacs already
+installed. You can add your normal config files as a volume, enabling you to use your
+preferred settings.
+
+```shell
+docker run -v ${HOME}/.vimrc:/root/.vimrc -v $(pwd)/..:/dpdk -it dpdk-dts bash
+```
+
+### Visual Studio Code
+VSCode has first-class support for developing with containers. You may need to run the
+non-docker setup commands in the integrated terminal. DTS contains a .devcontainer
+config, so if you open the folder in vscode it should prompt you to use the dev
+container assuming you have the plugin installed. Please refer to
+[VS Development Containers Docs](https://code.visualstudio.com/docs/remote/containers)
+to set it all up.
+
+### Other
+Searching for '$IDE dev containers' will probably lead you in the right direction.
-- 
2.30.2