Update docker images for Ruby

tools/dockerfile/distribtest/ruby_jessie_x64_ruby_2_4/Dockerfile

@@ -27,11 +27,11 @@ RUN gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A170311380
 RUN \curl -sSL https://get.rvm.io | bash -s stable
 
 # Install Ruby 2.4
-RUN /bin/bash -l -c "rvm install ruby-2.4.5"
-RUN /bin/bash -l -c "rvm use --default ruby-2.4.5"
+RUN /bin/bash -l -c "rvm install ruby-2.4.9"
+RUN /bin/bash -l -c "rvm use --default ruby-2.4.9"
 RUN /bin/bash -l -c "echo 'gem: --no-document' > ~/.gemrc"
 RUN /bin/bash -l -c "echo 'export PATH=/usr/local/rvm/bin:$PATH' >> ~/.bashrc"
-RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.4.5' >> ~/.bashrc"
+RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.4.9' >> ~/.bashrc"
 RUN /bin/bash -l -c "gem install bundler -v 1.17.3 --no-document"
 
 RUN mkdir /var/local/jenkins

tools/dockerfile/distribtest/ruby_jessie_x64_ruby_2_5/Dockerfile

@@ -27,11 +27,11 @@ RUN gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A170311380
 RUN \curl -sSL https://get.rvm.io | bash -s stable
 
 # Install Ruby 2.5
-RUN /bin/bash -l -c "rvm install ruby-2.5.3"
-RUN /bin/bash -l -c "rvm use --default ruby-2.5.3"
+RUN /bin/bash -l -c "rvm install ruby-2.5.7"
+RUN /bin/bash -l -c "rvm use --default ruby-2.5.7"
 RUN /bin/bash -l -c "echo 'gem: --no-document' > ~/.gemrc"
 RUN /bin/bash -l -c "echo 'export PATH=/usr/local/rvm/bin:$PATH' >> ~/.bashrc"
-RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.5.3' >> ~/.bashrc"
+RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.5.7' >> ~/.bashrc"
 RUN /bin/bash -l -c "gem install bundler -v 1.17.3 --no-document"
 
 RUN mkdir /var/local/jenkins

tools/dockerfile/distribtest/ruby_jessie_x64_ruby_2_6/Dockerfile

@@ -27,11 +27,11 @@ RUN gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A170311380
 RUN \curl -sSL https://get.rvm.io | bash -s stable
 
 # Install Ruby 2.6
-RUN /bin/bash -l -c "rvm install ruby-2.6.0"
-RUN /bin/bash -l -c "rvm use --default ruby-2.6.0"
+RUN /bin/bash -l -c "rvm install ruby-2.6.5"
+RUN /bin/bash -l -c "rvm use --default ruby-2.6.5"
 RUN /bin/bash -l -c "echo 'gem: --no-document' > ~/.gemrc"
 RUN /bin/bash -l -c "echo 'export PATH=/usr/local/rvm/bin:$PATH' >> ~/.bashrc"
-RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.6.0' >> ~/.bashrc"
+RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.6.5' >> ~/.bashrc"
 RUN /bin/bash -l -c "gem install bundler --no-document"
 
 RUN mkdir /var/local/jenkins

tools/dockerfile/distribtest/ruby_jessie_x64_ruby_2_7/Dockerfile

@@ -0,0 +1,40 @@
+# Copyright 2020 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+FROM debian:jessie
+
+# Install Git and basic packages.
+RUN apt-get update && apt-get install -y \
+  curl \
+  gcc && apt-get clean
+
+#==================
+# Ruby dependencies
+
+# Install rvm
+RUN gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+RUN \curl -sSL https://get.rvm.io | bash -s stable
+
+# Install Ruby 2.7
+RUN /bin/bash -l -c "rvm install ruby-2.7.0"
+RUN /bin/bash -l -c "rvm use --default ruby-2.7.0"
+RUN /bin/bash -l -c "echo 'gem: --no-document' > ~/.gemrc"
+RUN /bin/bash -l -c "echo 'export PATH=/usr/local/rvm/bin:$PATH' >> ~/.bashrc"
+RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.7.0' >> ~/.bashrc"
+RUN /bin/bash -l -c "gem install bundler --no-document"
+
+RUN mkdir /var/local/jenkins
+
+# Define the default command.
+CMD ["bash"]

tools/run_tests/artifacts/distribtest_targets.py

@@ -340,6 +340,7 @@ def targets():
         RubyDistribTest('linux', 'x64', 'jessie', ruby_version='ruby_2_4'),
         RubyDistribTest('linux', 'x64', 'jessie', ruby_version='ruby_2_5'),
         RubyDistribTest('linux', 'x64', 'jessie', ruby_version='ruby_2_6'),
+        # RubyDistribTest('linux', 'x64', 'jessie', ruby_version='ruby_2_7'),
         RubyDistribTest('linux', 'x64', 'centos6'),
         RubyDistribTest('linux', 'x64', 'centos7'),
         RubyDistribTest('linux', 'x64', 'fedora23'),