require ubuntu 20.04, test on debian 10

.github/workflows/integration-test.yaml

@@ -58,36 +58,28 @@ jobs:
           echo $matrix_post_filter | jq -C '.'
         env:
           matrix_include_pre_filter: |
-            - name: "Int. tests: Ubuntu 18.04, Py 3.6"
-              ubuntu_version: "18.04"
-              python_version: "3.6"
+            - name: "Int. tests: Debian 10, Py 3.7"
+              distro_image: "debian:10"
+              runs_on: "ubuntu-22.04"
               extra_flags: ""
-            - name: "Int. tests: Ubuntu 20.04, Py 3.9"
-              ubuntu_version: "20.04"
-              python_version: "3.9"
+            - name: "Int. tests: Ubuntu 20.04, Py 3.8"
+              distro_image: "ubuntu:20.04"
               extra_flags: ""
-            - name: "Int. tests: Ubuntu 22.04, Py 3.10"
-              ubuntu_version: "22.04"
-              python_version: "3.10"
+            - name: "Int. tests: Ubuntu 22.04 (Py 3.10)"
+              distro_image: "ubuntu:22.04"
               extra_flags: ""
             - name: "Int. tests: Ubuntu 22.04, Py 3.10, --upgrade"
-              ubuntu_version: "22.04"
-              python_version: "3.10"
+              distro_image: "ubuntu:22.04"
               extra_flags: --upgrade
               dont_run_on_ref: refs/heads/master
 
   integration-tests:
     needs: decide-on-test-jobs-to-run
 
-    # runs-on can only be configured to the LTS releases of ubuntu (20.04,
-    # 22.04, ...), so if we want to test against the latest non-LTS release, we
-    # must compromise when configuring runs-on and configure runs-on to be the
-    # latest LTS release instead.
-    #
-    # This can have consequences because actions like actions/setup-python will
-    # mount cached installations associated with the chosen runs-on environment.
-    #
-    runs-on: ${{ format('ubuntu-{0}', matrix.runs_on || matrix.ubuntu_version) }}
+    # integration tests run in a container,
+    # not in the worker, so this version is not relevant to the tests
+    # and can be the same for all tested versions
+    runs-on: ubuntu-22.04
 
     name: ${{ matrix.name }}
     strategy:
@@ -98,7 +90,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v4
         with:
-          python-version: "${{ matrix.python_version }}"
+          python-version: "3.10"
 
       - name: Install pytest
         run: python3 -m pip install pytest
@@ -106,7 +98,7 @@ jobs:
       # We abort pytest after two failures as a compromise between wanting to
       # avoid a flood of logs while still understanding if multiple tests would
       # fail.
-      - name: Run bootstrap tests (Runs in/Builds ubuntu:${{ matrix.ubuntu_version }} derived image)
+      - name: Run bootstrap tests (Runs in/Builds ${{ matrix.distro_image }} derived image)
         run: |
           pytest --verbose --maxfail=2 --color=yes --durations=10 --capture=no \
               integration-tests/test_bootstrap.py
@@ -115,14 +107,14 @@ jobs:
           # integration-tests/test_bootstrap.py will build and start containers
           # based on this environment variable. This is similar to how
           # .github/integration-test.py build-image can take a --build-arg
-          # setting the ubuntu_version.
-          UBUNTU_VERSION: ${{ matrix.ubuntu_version }}
+          # setting the base image.
+          BASE_IMAGE: ${{ matrix.distro_image }}
 
       # We build a docker image from wherein we will work
-      - name: Build systemd image (Builds ubuntu:${{ matrix.ubuntu_version }} derived image)
+      - name: Build systemd image (Builds ${{ matrix.distro_image }} derived image)
         run: |
           .github/integration-test.py build-image \
-              --build-arg "ubuntu_version=${{ matrix.ubuntu_version }}"
+              --build-arg "BASE_IMAGE=${{ matrix.distro_image }}"
 
       # FIXME: Make the logic below easier to follow.
       # - In short, setting BOOTSTRAP_PIP_SPEC here, specifies from what
@@ -151,7 +143,7 @@ jobs:
           echo "BOOTSTRAP_PIP_SPEC=$BOOTSTRAP_PIP_SPEC" >> $GITHUB_ENV
           echo $BOOTSTRAP_PIP_SPEC
 
-      - name: Run basic tests (Runs in ubuntu:${{ matrix.ubuntu_version }} derived image)
+      - name: Run basic tests (Runs in ${{ matrix.distro_image }} derived image)
         run: |
           .github/integration-test.py run-test basic-tests \
               --bootstrap-pip-spec "$BOOTSTRAP_PIP_SPEC" \
@@ -162,7 +154,7 @@ jobs:
               test_extensions.py
         timeout-minutes: 15
 
-      - name: Run admin tests (Runs in ubuntu:${{ matrix.ubuntu_version }} derived image)
+      - name: Run admin tests (Runs in ${{ matrix.distro_image }} derived image)
         run: |
           .github/integration-test.py run-test admin-tests \
               --installer-args "--admin admin:admin" \
@@ -171,7 +163,7 @@ jobs:
               test_admin_installer.py
         timeout-minutes: 15
 
-      - name: Run plugin tests (Runs in ubuntu:${{ matrix.ubuntu_version }} derived image)
+      - name: Run plugin tests (Runs in ${{ matrix.distro_image }} derived image)
         run: |
           .github/integration-test.py run-test plugin-tests \
               --bootstrap-pip-spec "$BOOTSTRAP_PIP_SPEC" \

.github/workflows/unit-test.yaml

@@ -42,9 +42,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - name: "Unit tests: Ubuntu 18.04, Py 3.6"
-            ubuntu_version: "18.04"
-            python_version: "3.6"
           - name: "Unit tests: Ubuntu 20.04, Py 3.9"
             ubuntu_version: "20.04"
             python_version: "3.9"

README.md

@@ -36,7 +36,7 @@ might still make breaking changes that have no clear upgrade pathway.
 ## Installation
 
 The Littlest JupyterHub (TLJH) can run on any server that is running at least
-**Ubuntu 18.04**. Earlier versions of Ubuntu are not supported.
+**Ubuntu 20.04**. Earlier versions of Ubuntu are not supported.
 We have several tutorials to get you started.
 
 - Tutorials to create a new server from scratch on a cloud provider & run TLJH

bootstrap/bootstrap.py

@@ -9,11 +9,10 @@ This script is run as:
 
 Constraints:
 
-    - The entire script should be compatible with Python 3.6, which is the on
-      Ubuntu 18.04+.
-    - The script should parse in Python 3.5 as we print error messages for using
-      Ubuntu 16.04+ which comes with Python 3.5 by default. This means no
-      f-strings can be used.
+    - The entire script should be compatible with Python 3.7, which is the on
+      Debian 10.
+    - The script should parse in Python 3.6 as we print error messages for using
+      Ubuntu 18.04+ which comes with Python 3.6 by default.
     - The script must depend only on stdlib modules, as no previous installation
       of dependencies can be assumed.
 
@@ -132,6 +131,12 @@ progress_page_html = """
 
 logger = logging.getLogger(__name__)
 
+
+def _parse_version(vs):
+    """Parse a simple version into a tuple of ints"""
+    return (int(part) for part in vs.split("."))
+
+
 # This function is needed both by the process starting this script, and by the
 # TLJH installer that this script execs in the end. Make sure its replica at
 # tljh/utils.py stays in sync with this version!
@@ -199,22 +204,22 @@ def ensure_host_system_can_install_tljh():
             .strip()
         )
 
-    # Require Ubuntu 18.04+ or Debian 10+
+    # Require Ubuntu 20.04+ or Debian 10+
     distro = get_os_release_variable("ID")
     version = float(get_os_release_variable("VERSION_ID"))
     if distro not in ["ubuntu", "debian"]:
         print("The Littlest JupyterHub currently supports Ubuntu or Debian Linux only")
         sys.exit(1)
-    elif distro == "ubuntu" and float(version) < 18.04:
-        print("The Littlest JupyterHub requires Ubuntu 18.04 or higher")
+    elif distro == "ubuntu" and _parse_version(version) < (20, 4):
+        print("The Littlest JupyterHub requires Ubuntu 20.04 or higher")
         sys.exit(1)
-    elif distro == "debian" and float(version) < 10:
+    elif distro == "debian" and _parse_version(version) < (10,):
         print("The Littlest JupyterHub requires Debian 10 or higher")
         sys.exit(1)
 
     # Require Python 3.6+
-    if sys.version_info < (3, 6):
-        print("bootstrap.py must be run with at least Python 3.6")
+    if sys.version_info < (3, 7):
+        print(f"bootstrap.py must be run with at least Python 3.7, found {sys.version}")
         sys.exit(1)
 
     # Require systemd (systemctl is a part of systemd)
@@ -441,7 +446,7 @@ def main():
                 "python3-venv",
                 "python3-pip",
                 "git",
-                "sudo", # sudo is missing in default debian install
+                "sudo",  # sudo is missing in default debian install
             ],
             env=apt_get_adjusted_env,
         )

docs/index.rst

@@ -17,7 +17,7 @@ might still make breaking changes that have no clear upgrade pathway.
 Installation
 ============
 
-The Littlest JupyterHub (TLJH) can run on any server that is running **Ubuntu 18.04** or **Ubuntu 20.04** on a amd64 or arm64 CPU architecture. Earlier versions of Ubuntu are not supported.
+The Littlest JupyterHub (TLJH) can run on any server that is running **Debian 10** or **Ubuntu 20.04** on a amd64 or arm64 CPU architecture. Earlier versions of Ubuntu and Debian are not supported, as are other Linux distributions.
 We have a bunch of tutorials to get you started.
 
 - Tutorials to create a new server from scratch on a cloud provider & run TLJH

docs/install/amazon.rst

@@ -58,15 +58,15 @@ Let's create the server on which we can run JupyterHub.
 #. On the page **Step 1: Choose an Amazon Machine Image (AMI)** you are going
    to pick the base image your remote server will have. The view will
    default to the 'Quick-start' tab selected and just a few down the page, select
-   **Ubuntu Server 18.04 LTS (HVM), SSD Volume Type - ami-XXXXXXXXXXXXXXXXX**,
+   **Ubuntu Server 22.04 LTS (HVM), SSD Volume Type - ami-XXXXXXXXXXXXXXXXX**,
    leaving `64-bit (x86)` toggled.
 
    .. image:: ../images/providers/amazon/select_ubuntu_18.png
-      :alt: Click Ubuntu server 18.04
+      :alt: Click Ubuntu server 22.04
 
    The `ami` alpha-numeric at the end references the specific Amazon machine
    image, ignore this as Amazon updates them routinely. The
-   **Ubuntu Server 18.04 LTS (HVM)** is the important part.
+   **Ubuntu Server 22.04 LTS (HVM)** is the important part.
 
 
 #. After selecting the AMI, you'll be at **Step 2: Choose an Instance Type**.

docs/install/azure.rst

@@ -52,7 +52,7 @@ A new screen with all the options for Virtual Machines in Azure will displayed.
         :alt: Create VM from the marketplace
 
 #. **Choose an Ubuntu server for your VM**:
-    * Click `Ubuntu Server 18.04 LTS.`
+    * Click `Ubuntu Server 22.04 LTS.`
     * Make sure `Resource Manager` is selected in the next screen and click **Create**
 
     .. image:: ../images/providers/azure/ubuntu-vm.png
@@ -70,7 +70,7 @@ A new screen with all the options for Virtual Machines in Azure will displayed.
     * **Name**. Use a descriptive name for your virtual machine (note that you cannot use spaces or special characters).
     * **Region**. Choose a location near where you expect your users to be located.
     * **Availability options**. Choose "No infrastructure redundancy required".
-    * **Image**. Make sure "Ubuntu Server 18.04 LTS" is selected (from the previous step).
+    * **Image**. Make sure "Ubuntu Server 22.04 LTS" is selected (from the previous step).
     * **Authentication type**. Change authentication type to "password".
     * **Username**. Choose a memorable username, this will be your "root" user, and you'll need it later on.
     * **Password**. Type in a password, this will be used later for admin access so make sure it is something memorable.

docs/install/custom-server.rst

@@ -31,7 +31,7 @@ Pre-requisites
 ==============
 
 #. Some familiarity with the command line.
-#. A server running Ubuntu 18.04 where you have root access.
+#. A server running Ubuntu 20.04 where you have root access.
 #. At least **1GB** of RAM on your server.
 #. Ability to ``ssh`` into the server & run commands from the prompt.
 #. An **IP address** where the server can be reached from the browsers of your target audience.

docs/install/digitalocean.rst

@@ -34,10 +34,10 @@ Let's create the server on which we can run JupyterHub.
    This takes you to a page titled **Create Droplets** that lets you configure
    your server.
 
-#. Under **Choose an image**, select **18.04 x64** under **Ubuntu**.
+#. Under **Choose an image**, select **22.04 x64** under **Ubuntu**.
 
    .. image:: ../images/providers/digitalocean/select-image.png
-      :alt: Select 18.04 x64 image under Ubuntu
+      :alt: Select 22.04 x64 image under Ubuntu
 
 #. Under **Choose a size**, select the size of the server you want. The default
    (4GB RAM, 2CPUs, 20 USD / month) is not a bad start. You can resize your server

docs/install/google.rst

@@ -94,10 +94,10 @@ Let's create the server on which we can run JupyterHub.
 
    This should open a **Boot disk** popup.
 
-#. Select **Ubuntu 18.04 LTS** from the list of operating system images.
+#. Select **Ubuntu 22.04 LTS** from the list of operating system images.
 
    .. image:: ../images/providers/google/boot-disk-ubuntu.png
-      :alt: Selecting Ubuntu 18.04 for OS
+      :alt: Selecting Ubuntu 22.04 for OS
 
 #. You can also change the **type** and **size** of your disk at the bottom
    of this popup.

docs/install/index.rst

@@ -5,7 +5,8 @@ Installing
 ==========
 
 The Littlest JupyterHub (TLJH) can run on any server that is running at least
-**Ubuntu 18.04**. Earlier versions of Ubuntu are not supported.
+**Ubuntu 20.04** or **Debian 10**. Earlier versions of Ubuntu and Debian are not supported,
+nor are other Linux distributions.
 We have a bunch of tutorials to get you started.
 
 Tutorials to create a new server from scratch on a cloud provider & run TLJH

docs/install/jetstream.rst

@@ -33,11 +33,11 @@ Let's create the server on which we can run JupyterHub.
    This takes you to a page with a list of base images you can choose for your
    server.
 
-#. Under **Image Search**, search for **Ubuntu 18.04**, and select the
-   **Ubuntu 18.04 Devel and Docker** image.
+#. Under **Image Search**, search for **Ubuntu 22.04**, and select the
+   **Ubuntu 22.04 Devel and Docker** image.
 
    .. image:: ../images/providers/jetstream/select-image.png
-      :alt: Select Ubuntu 18.04 x64 image from image list
+      :alt: Select Ubuntu 22.04 x64 image from image list
 
 #. Once selected, you will see more information about this image. Click the
    **Launch** button on the top right.

docs/install/ovh.rst

@@ -52,10 +52,10 @@ Let's create the server on which we can run JupyterHub.
 
 #. **Select a region**.
 
-#. Select **Ubuntu 18.04** as the image:
+#. Select **Ubuntu 22.04** as the image:
 
    .. image:: ../images/providers/ovh/distribution.png
-      :alt: Select Ubuntu 18.04 as the image
+      :alt: Select Ubuntu 22.04 as the image
 
 #. OVH requires setting an SSH key to be able to connect to the instance.
    You can create a new SSH by following

docs/topic/requirements.rst

@@ -7,7 +7,7 @@ Server Requirements
 Operating System
 ================
 
-We require using Ubuntu 18.04 as the base operating system for your server.
+We require using Ubuntu >=20.04 as the base operating system for your server.
 
 Root access
 ===========

integration-tests/Dockerfile

@@ -1,6 +1,6 @@
 # Systemd inside a Docker container, for CI only
-ARG ubuntu_version=20.04
-FROM ubuntu:${ubuntu_version}
+ARG BASE_IMAGE=ubuntu:20.04
+FROM $BASE_IMAGE
 
 # DEBIAN_FRONTEND is set to avoid being asked for input and hang during build:
 # https://anonoz.github.io/tech/2020/04/24/docker-build-stuck-tzdata.html

integration-tests/test_bootstrap.py

@@ -6,6 +6,8 @@ import os
 import subprocess
 import time
 
+BASE_IMAGE = os.getenv("BASE_IMAGE", "ubuntu:20.04")
+
 
 def install_pkgs(container_name, show_progress_page):
     # Install python3 inside the ubuntu container
@@ -13,7 +15,7 @@ def install_pkgs(container_name, show_progress_page):
     pkgs = ["python3"]
     if show_progress_page:
         pkgs += ["systemd", "git", "curl"]
-        # Create the sudoers dir, so that the installer succesfully gets to the
+        # Create the sudoers dir, so that the installer successfully gets to the
         # point of starting jupyterhub and stopping the progress page server.
         subprocess.check_output(
             ["docker", "exec", container_name, "mkdir", "-p", "etc/sudoers.d"]
@@ -128,15 +130,15 @@ def test_ubuntu_too_old():
     """
     Error with a useful message when running in older Ubuntu
     """
-    output = run_bootstrap_after_preparing_container("old-distro-test", "ubuntu:16.04")
-    assert output.stdout == "The Littlest JupyterHub requires Ubuntu 18.04 or higher\n"
+    output = run_bootstrap_after_preparing_container("old-distro-test", "ubuntu:18.04")
+    assert output.stdout == "The Littlest JupyterHub requires Ubuntu 20.04 or higher\n"
     assert output.returncode == 1
 
 
 def test_inside_no_systemd_docker():
     output = run_bootstrap_after_preparing_container(
         "plain-docker-test",
-        f"ubuntu:{os.getenv('UBUNTU_VERSION', '20.04')}",
+        BASE_IMAGE,
     )
     assert "Systemd is required to run TLJH" in output.stdout
     assert output.returncode == 1
@@ -172,7 +174,7 @@ def test_progress_page():
         installer = executor.submit(
             run_bootstrap_after_preparing_container,
             "progress-page",
-            f"ubuntu:{os.getenv('UBUNTU_VERSION', '20.04')}",
+            BASE_IMAGE,
             True,
         )