Merge pull request #909 from yuvipanda/feat/new-base

Let `FROM <base_image>` in the Dockerfile template be configurable

Author: minrk

Dockerfile

@@ -1,8 +1,8 @@
 # syntax = docker/dockerfile:1.3
-ARG ALPINE_VERSION=3.16
+ARG ALPINE_VERSION=3.17
 FROM alpine:${ALPINE_VERSION}
 
-RUN apk add --no-cache git python3 python3-dev py-pip build-base
+RUN apk add --no-cache git python3 python3-dev py3-pip py3-setuptools build-base
 
 # build wheels in first image
 ADD . /tmp/src
@@ -16,7 +16,7 @@ RUN mkdir /tmp/wheelhouse \
 FROM alpine:${ALPINE_VERSION}
 
 # install python, git, bash, mercurial
-RUN apk add --no-cache git git-lfs python3 py-pip bash docker mercurial
+RUN apk add --no-cache git git-lfs python3 py3-pip py3-setuptools bash docker mercurial
 
 # install hg-evolve (Mercurial extensions)
 RUN pip3 install hg-evolve --user --no-cache-dir

docs/source/howto/base_image.md

@@ -0,0 +1,33 @@
+# Change the base image used by Docker
+
+You may change the base image used in the `Dockerfile` that creates images by repo2docker.
+This is equivalent to changing the `FROM <base_image>` in the Dockerfile.
+
+To do so, use the `base_image` traitlet when invoking `repo2docker`.
+Note that this is not configurable by individual repositories, it is configured when you invoke the `repo2docker` command.
+
+```{note}
+By default repo2docker builds on top of the `buildpack-deps:bionic` base image, an Ubuntu-based image.
+```
+
+## Requirements for your base image
+
+`repo2docker` will only work if a specific set of packages exists in the base image.
+Only images that match the following criteria are supported:
+
+- Ubuntu based distributions (minimum `18.04`)
+- Contains a set of base packages installed with [the `buildpack-deps` image family](https://hub.docker.com/_/buildpack-deps).
+
+Other images _may_ work, but are not officially supported.
+
+## This will affect reproducibility 🚨
+
+Changing the base image may have an impact on the reproducibility of repositories that are built.
+There are **no guarantees that repositories will behave the same way as other repo2docker builds if you change the base image**.
+For example these are two scenarios that would make your repositories non-reproducible:
+
+- **Your base image is different from `Ubuntu:bionic`.**
+  If you change the base image in a way that is different from repo2docker's default (the Ubuntu `bionic` image), then repositories that **you** build with repo2docker may be significantly different from those that **other** instances of repo2docker build (e.g., those from [`mybinder.org`](https://mybinder.org)).
+- **Your base image changes over time.**
+  If you choose a base image that changes its composition over time (e.g., an image provided by some other community), then it may cause repositories build with your base image to change in unpredictable ways.
+  We recommend choosing a base image that you know to be stable and trustworthy.

docs/source/howto/index.rst

@@ -15,3 +15,4 @@ Select from the pages listed below to get started.
    lab_workspaces
    jupyterhub_images
    deploy
+   base_image

repo2docker/app.py

@@ -447,6 +447,21 @@ def _dry_run_changed(self, change):
         """,
     )
 
+    base_image = Unicode(
+        "docker.io/library/buildpack-deps:bionic",
+        config=True,
+        help="""
+        Base image to use when building docker images.
+
+        Only images that match the following criteria are supported:
+        - Ubuntu based distributions, minimum 18.04
+        - Contains set of base packages installed with the buildpack-deps
+          image family: https://hub.docker.com/_/buildpack-deps
+
+        Other images *may* work, but are not officially supported.
+        """,
+    )
+
     def get_engine(self):
         """Return an instance of the container engine.
 
@@ -793,12 +808,14 @@ def build(self):
 
             with chdir(checkout_path):
                 for BP in self.buildpacks:
-                    bp = BP()
+                    bp = BP(base_image=self.base_image)
                     if bp.detect():
                         picked_buildpack = bp
                         break
                 else:
-                    picked_buildpack = self.default_buildpack()
+                    picked_buildpack = self.default_buildpack(
+                        base_image=self.base_image
+                    )
 
                 picked_buildpack.platform = self.platform
                 picked_buildpack.appendix = self.appendix

repo2docker/buildpacks/_r_base.py

@@ -14,9 +14,19 @@ def rstudio_base_scripts(r_version):
     shiny_proxy_version = "1.1"
     shiny_sha256sum = "80f1e48f6c824be7ef9c843bb7911d4981ac7e8a963e0eff823936a8b28476ee"
 
-    rstudio_url = "https://download2.rstudio.org/server/bionic/amd64/rstudio-server-2022.02.1-461-amd64.deb"
-    rstudio_sha256sum = (
-        "239e8d93e103872e7c6d827113d88871965f82ffb0397f5638025100520d8a54"
+    # RStudio server has different builds based on wether OpenSSL 3 or 1.1 is available in the base
+    # image. 3 is present Jammy+, 1.1 until then. Instead of hardcoding URLs based on distro, we actually
+    # check for the dependency itself directly in the code below. You can find these URLs in
+    # https://posit.co/download/rstudio-server/, toggling between Ubuntu 22 (for openssl3) vs earlier versions (openssl 1.1)
+    # you may forget about openssl, but openssl never forgets you.
+    rstudio_openssl3_url = "https://download2.rstudio.org/server/jammy/amd64/rstudio-server-2022.12.0-353-amd64.deb"
+    rstudio_openssl3_sha256sum = (
+        "a5aa2202786f9017a6de368a410488ea2e4fc6c739f78998977af214df0d6288"
+    )
+
+    rstudio_openssl1_url = "https://download2.rstudio.org/server/bionic/amd64/rstudio-server-2022.12.0-353-amd64.deb"
+    rstudio_openssl1_sha256sum = (
+        "bb88e37328c304881e60d6205d7dac145525a5c2aaaf9da26f1cb625b7d47e6e"
     )
     rsession_proxy_version = "2.0.1"
 
@@ -27,11 +37,18 @@ def rstudio_base_scripts(r_version):
             # but here it's important because these recommend r-base,
             # which will upgrade the installed version of R, undoing our pinned version
             rf"""
-            curl --silent --location --fail {rstudio_url} > /tmp/rstudio.deb && \
+            apt-get update > /dev/null && \
+            if apt-cache search libssl3 > /dev/null; then \
+              RSTUDIO_URL="{rstudio_openssl3_url}" ;\
+              RSTUDIO_HASH="{rstudio_openssl3_sha256sum}" ;\
+            else \
+              RSTUDIO_URL="{rstudio_openssl1_url}" ;\
+              RSTUDIO_HASH="{rstudio_openssl1_sha256sum}" ;\
+            fi && \
+            curl --silent --location --fail ${{RSTUDIO_URL}} > /tmp/rstudio.deb && \
             curl --silent --location --fail {shiny_server_url} > /tmp/shiny.deb && \
-            echo '{rstudio_sha256sum} /tmp/rstudio.deb' | sha256sum -c - && \
+            echo "${{RSTUDIO_HASH}} /tmp/rstudio.deb" | sha256sum -c - && \
             echo '{shiny_sha256sum} /tmp/shiny.deb' | sha256sum -c - && \
-            apt-get update > /dev/null && \
             apt install -y --no-install-recommends /tmp/rstudio.deb /tmp/shiny.deb && \
             rm /tmp/*.deb && \
             apt-get -qq purge && \

repo2docker/buildpacks/base.py

@@ -14,7 +14,7 @@
 
 # Only use syntax features supported by Docker 17.09
 TEMPLATE = r"""
-FROM buildpack-deps:bionic
+FROM {{base_image}}
 
 # Avoid prompts from apt
 ENV DEBIAN_FRONTEND=noninteractive
@@ -211,7 +211,6 @@ class BuildPack:
     Specifically used for creating Dockerfiles for use with repo2docker only.
 
     Things that are kept constant:
-     - base image
      - some environment variables (such as locale)
      - user creation & ownership of home directory
      - working directory
@@ -221,9 +220,13 @@ class BuildPack:
 
     """
 
-    def __init__(self):
+    def __init__(self, base_image):
+        """
+        base_image specifies the base image to use when building docker images
+        """
         self.log = logging.getLogger("repo2docker")
         self.appendix = ""
+        self.base_image = base_image
         self.labels = {}
         if sys.platform.startswith("win"):
             self.log.warning(
@@ -257,6 +260,8 @@ def get_base_packages(self):
             # Utils!
             "less",
             "unzip",
+            # Gives us envsubst
+            "gettext-base",
         }
 
     @lru_cache()
@@ -535,6 +540,7 @@ def render(self, build_args=None):
             appendix=self.appendix,
             # For docker 17.09 `COPY --chown`, 19.03 would allow using $NBUSER
             user=build_args.get("NB_UID", DEFAULT_NB_UID),
+            base_image=self.base_image,
         )
 
     @staticmethod

repo2docker/buildpacks/legacy/__init__.py

@@ -16,6 +16,9 @@ class LegacyBinderDockerBuildPack:
     This buildpack has been deprecated.
     """
 
+    def __init__(self, *args, **kwargs):
+        pass
+
     def detect(self):
         """Check if current repo should be built with the Legacy BuildPack."""
         log = logging.getLogger("repo2docker")

repo2docker/buildpacks/r.py

@@ -196,6 +196,7 @@ def get_packages(self):
             "libapparmor1",
             "sudo",
             "lsb-release",
+            "libssl-dev",
         ]
 
         return super().get_packages().union(packages)
@@ -216,7 +217,10 @@ def get_rspm_snapshot_url(self, snapshot_date, max_days_prior=7):
             # Construct a snapshot URL that will give us binary packages for Ubuntu Bionic (18.04)
             if "upsi" in snapshots:
                 return (
-                    "https://packagemanager.posit.co/all/__linux__/bionic/"
+                    # Env variables here are expanded by envsubst in the Dockerfile, after sourcing
+                    # /etc/os-release. This allows us to use distro specific variables here to get
+                    # appropriate binary packages without having to hard code version names here.
+                    "https://packagemanager.posit.co/all/__linux__/${VERSION_CODENAME}/"
                     + snapshots["upsi"]
                 )
         raise ValueError(
@@ -262,7 +266,10 @@ def get_devtools_snapshot_url(self):
         # Hardcoded rather than dynamically determined from a date to avoid extra API calls
         # Plus, we can always use packagemanager.posit.co here as we always install the
         # necessary apt packages.
-        return "https://packagemanager.posit.co/all/__linux__/bionic/2022-01-04+Y3JhbiwyOjQ1MjYyMTU7NzlBRkJEMzg"
+        # Env variables here are expanded by envsubst in the Dockerfile, after sourcing
+        # /etc/os-release. This allows us to use distro specific variables here to get
+        # appropriate binary packages without having to hard code version names here.
+        return "https://packagemanager.posit.co/all/__linux__/${VERSION_CODENAME}/2022-06-03+Y3JhbiwyOjQ1MjYyMTU7RkM5ODcwN0M"
 
     @lru_cache()
     def get_build_scripts(self):
@@ -343,16 +350,18 @@ def get_build_scripts(self):
                 rf"""
                 R RHOME && \
                 mkdir -p /etc/rstudio && \
-                echo 'options(repos = c(CRAN = "{cran_mirror_url}"))' > /opt/R/{self.r_version}/lib/R/etc/Rprofile.site && \
-                echo 'r-cran-repos={cran_mirror_url}' > /etc/rstudio/rsession.conf
+                EXPANDED_CRAN_MIRROR_URL="$(. /etc/os-release && echo {cran_mirror_url} | envsubst)" && \
+                echo "options(repos = c(CRAN = \"${{EXPANDED_CRAN_MIRROR_URL}}\"))" > /opt/R/{self.r_version}/lib/R/etc/Rprofile.site && \
+                echo "r-cran-repos=${{EXPANDED_CRAN_MIRROR_URL}}" > /etc/rstudio/rsession.conf
                 """,
             ),
             (
                 "${NB_USER}",
                 # Install a pinned version of devtools, IRKernel and shiny
                 rf"""
-                R --quiet -e "install.packages(c('devtools', 'IRkernel', 'shiny'), repos='{self.get_devtools_snapshot_url()}')" && \
-                R --quiet -e "IRkernel::installspec(prefix='$NB_PYTHON_PREFIX')"
+                export EXPANDED_CRAN_MIRROR_URL="$(. /etc/os-release && echo {cran_mirror_url} | envsubst)" && \
+                R --quiet -e "install.packages(c('devtools', 'IRkernel', 'shiny'), repos=Sys.getenv(\"EXPANDED_CRAN_MIRROR_URL\"))" && \
+                R --quiet -e "IRkernel::installspec(prefix=Sys.getenv(\"NB_PYTHON_PREFIX\"))"
                 """,
             ),
         ]

repo2docker/contentproviders/git.py

@@ -45,10 +45,10 @@ def fetch(self, spec, output_dir, yield_output=False):
                 self.log.error(
                     f"Failed to check out ref {ref}", extra=dict(phase=R2dState.FAILED)
                 )
-                if ref == "master":
+                if ref == "master" or ref == "main":
                     msg = (
-                        "Failed to check out the 'master' branch. "
-                        "Maybe the default branch is not named 'master' "
+                        f"Failed to check out the '{ref}' branch. "
+                        f"Maybe the default branch is not named '{ref}' "
                         "for this repository.\n\nTry not explicitly "
                         "specifying `--ref`."
                     )

tests/conftest.py

@@ -100,6 +100,14 @@ def run_test(args):
     return run_test
 
 
+@pytest.fixture()
+def base_image():
+    """
+    Base ubuntu image to use when testing specific BuildPacks
+    """
+    return "buildpack-deps:bionic"
+
+
 def _add_content_to_git(repo_dir):
     """Add content to file 'test' in git repository and commit."""
     # use append mode so this can be called multiple times