GH-45476: [Packaging][Linux] Drop support for Ubuntu 20.04 (#45477)

### Rationale for this change

Ubuntu 20.04 will reach EOL on 2025-05.

### What changes are included in this PR?

Remove Ubuntu 20.04 related codes.

### Are these changes tested?

Yes.

### Are there any user-facing changes?

Yes.
* GitHub Issue: #45476

Authored-by: Sutou Kouhei <kou@clear-code.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>

dev/release/binary-task.rb

@@ -1086,7 +1086,6 @@ def available_apt_targets
     [
       ["debian", "bookworm", "main"],
       ["debian", "trixie", "main"],
-      ["ubuntu", "focal", "main"],
       ["ubuntu", "jammy", "main"],
       ["ubuntu", "noble", "main"],
     ]
@@ -2105,8 +2104,6 @@ def apt_test_targets_default
       # "debian-bookworm-arm64",
       "debian-trixie",
       # "debian-trixie-arm64",
-      "ubuntu-focal",
-      # "ubuntu-focal-arm64",
       "ubuntu-jammy",
       # "ubuntu-jammy-arm64",
       "ubuntu-noble",

dev/release/verify-release-candidate.sh

@@ -186,7 +186,6 @@ test_apt() {
   if [ "$(arch)" = "x86_64" ]; then
     for target in "debian:bookworm" \
                   "debian:trixie" \
-                  "ubuntu:focal" \
                   "ubuntu:jammy" \
                   "ubuntu:noble"; do \
       if ! docker run \
@@ -207,7 +206,6 @@ test_apt() {
   if [ "$(arch)" = "aarch64" -o -e /usr/bin/qemu-aarch64-static ]; then
     for target in "arm64v8/debian:bookworm" \
                   "arm64v8/debian:trixie" \
-                  "arm64v8/ubuntu:focal" \
                   "arm64v8/ubuntu:jammy" \
                   "arm64v8/ubuntu:noble"; do \
       if ! docker run \

dev/tasks/linux-packages/apache-arrow/Rakefile

@@ -96,31 +96,9 @@ class ApacheArrowPackageTask < PackageTask
     control.gsub(/@CUDA_ARCHITECTURE@/, cuda_architecture)
   end
 
-  def apt_prepare_debian_control_grpc(control, target)
-    case target
-    when /\Aubuntu-focal/
-      use_system_grpc = "#"
-    else
-      use_system_grpc = ""
-    end
-    control.gsub(/@USE_SYSTEM_GRPC@/, use_system_grpc)
-  end
-
-  def apt_prepare_debian_control_protobuf(control, target)
-    case target
-    when /\Aubuntu-focal/
-      use_system_protobuf = "#"
-    else
-      use_system_protobuf = ""
-    end
-    control.gsub(/@USE_SYSTEM_PROTOBUF@/, use_system_protobuf)
-  end
-
   def apt_prepare_debian_control(control_in, target)
     control = control_in.dup
     control = apt_prepare_debian_control_cuda_architecture(control, target)
-    control = apt_prepare_debian_control_grpc(control, target)
-    control = apt_prepare_debian_control_protobuf(control, target)
     control
   end
 end

dev/tasks/linux-packages/apache-arrow/debian/control.in

@@ -5,8 +5,7 @@ Maintainer: Apache Arrow Developers <dev@arrow.apache.org>
 Build-Depends:
   cmake,
   debhelper (>= 12),
-# TODO: Enable this after we drop support for Ubuntu 20.04.
-#  gi-docgen,
+  gi-docgen,
   git,
   gobject-introspection,
   libboost-filesystem-dev,
@@ -17,11 +16,11 @@ Build-Depends:
   libcurl4-openssl-dev,
   libgirepository1.0-dev,
   libgoogle-glog-dev,
-@USE_SYSTEM_GRPC@  libgrpc++-dev,
+  libgrpc++-dev,
   libgtest-dev,
   liblz4-dev,
-@USE_SYSTEM_PROTOBUF@  libprotobuf-dev,
-@USE_SYSTEM_PROTOBUF@  libprotoc-dev,
+  libprotobuf-dev,
+  libprotoc-dev,
   libre2-dev,
   libsnappy-dev,
   libssl-dev,
@@ -34,10 +33,10 @@ Build-Depends:
   nlohmann-json-dev | nlohmann-json3-dev,
   nvidia-cuda-toolkit [!arm64],
   pkg-config,
-@USE_SYSTEM_PROTOBUF@  protobuf-compiler,
-@USE_SYSTEM_GRPC@  protobuf-compiler-grpc,
-  valac,
+  protobuf-compiler,
+  protobuf-compiler-grpc,
   tzdata,
+  valac,
   zlib1g-dev
 Build-Depends-Indep: libglib2.0-doc
 Standards-Version: 3.9.8
@@ -140,23 +139,23 @@ Architecture: any
 Multi-Arch: same
 Depends:
   ${misc:Depends},
+  libabsl-dev,
   libarrow2000 (= ${binary:Version}),
-@USE_SYSTEM_GRPC@  libabsl-dev,
   libbrotli-dev,
   libbz2-dev,
+  libc-ares-dev,
   libcurl4-openssl-dev,
   liblz4-dev,
-  libc-ares-dev,
-@USE_SYSTEM_PROTOBUF@  libprotobuf-dev,
-@USE_SYSTEM_PROTOBUF@  libprotoc-dev,
+  libprotobuf-dev,
+  libprotoc-dev,
   libre2-dev,
   libsnappy-dev,
   libssl-dev,
   libutf8proc-dev,
   libxxhash-dev,
   libzstd-dev,
   nlohmann-json-dev | nlohmann-json3-dev,
-@USE_SYSTEM_GRPC@  protobuf-compiler-grpc,
+  protobuf-compiler-grpc,
   zlib1g-dev
 Description: Apache Arrow is a data processing library for analysis
  .
@@ -208,7 +207,7 @@ Depends:
   libarrow-dev (= ${binary:Version}),
   libarrow-flight2000 (= ${binary:Version}),
   libc-ares-dev,
-@USE_SYSTEM_GRPC@  libgrpc++-dev
+  libgrpc++-dev
 Description: Apache Arrow is a data processing library for analysis
  .
  This package provides C++ header files for Flight RPC system.

dev/tasks/linux-packages/package-task.rb

@@ -271,8 +271,6 @@ def apt_targets_default
       # "debian-bookworm-arm64",
       "debian-trixie",
       # "debian-trixie-arm64",
-      "ubuntu-focal",
-      # "ubuntu-focal-arm64",
       "ubuntu-jammy",
       # "ubuntu-jammy-arm64",
       "ubuntu-noble",

dev/tasks/tasks.yml

@@ -465,7 +465,6 @@ tasks:
 
 {% for target in ["debian-bookworm",
                   "debian-trixie",
-                  "ubuntu-focal",
                   "ubuntu-jammy",
                   "ubuntu-noble"] %}
   {% for architecture in ["amd64", "arm64"] %}