From ee50020b1d520fde50951ef7509d1079538547d6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Przemys=C5=82aw=20Hejman?= <przemyslaw.hejman@elastic.co>
Date: Tue, 8 Dec 2020 12:58:47 +0100
Subject: [PATCH] Introduce tini as init system for Docker containers (#22137)

Introduce tini as init system for Docker containers. Tini is the init system
used in docker images of other Elastic products.
It implements basic init functionality as reaping zombie processes and
properly handle signals.
---
 .../templates/docker/Dockerfile.elastic-agent.tmpl   | 12 +++++++++++-
 dev-tools/packaging/templates/docker/Dockerfile.tmpl | 12 +++++++++++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/dev-tools/packaging/templates/docker/Dockerfile.elastic-agent.tmpl b/dev-tools/packaging/templates/docker/Dockerfile.elastic-agent.tmpl
index 7c00afaca81..add0928a0c1 100644
--- a/dev-tools/packaging/templates/docker/Dockerfile.elastic-agent.tmpl
+++ b/dev-tools/packaging/templates/docker/Dockerfile.elastic-agent.tmpl
@@ -66,6 +66,16 @@ LABEL \
 ENV ELASTIC_CONTAINER "true"
 ENV PATH={{ $beatHome }}:$PATH
 
+# Add an init process, check the checksum to make sure it's a match
+RUN set -e ; \
+  TINI_VERSION='v0.19.0' ; \
+  TINI_BIN='tini-amd64' ; \
+  TINI_SHA256='93dcc18adc78c65a028a84799ecf8ad40c936fdfc5f2a57b1acda5a8117fa82c' ; \
+  curl --retry 8 -S -L -O "https://github.com/krallin/tini/releases/download/${TINI_VERSION}/${TINI_BIN}" ; \
+  echo "${TINI_SHA256} ${TINI_BIN}" | sha256sum -c - ; \
+  mv "${TINI_BIN}" /usr/bin/tini ; \
+  chmod +x /usr/bin/tini
+
 COPY docker-entrypoint /usr/local/bin/docker-entrypoint
 RUN chmod 755 /usr/local/bin/docker-entrypoint
 
@@ -90,4 +100,4 @@ EXPOSE {{ $port }}
 {{- end }}
 
 WORKDIR {{ $beatHome }}
-ENTRYPOINT ["/usr/local/bin/docker-entrypoint"]
+ENTRYPOINT ["/usr/bin/tini", "--", "/usr/local/bin/docker-entrypoint"]
diff --git a/dev-tools/packaging/templates/docker/Dockerfile.tmpl b/dev-tools/packaging/templates/docker/Dockerfile.tmpl
index f5cbccdcb20..05ea2583623 100644
--- a/dev-tools/packaging/templates/docker/Dockerfile.tmpl
+++ b/dev-tools/packaging/templates/docker/Dockerfile.tmpl
@@ -60,6 +60,16 @@ LABEL \
 ENV ELASTIC_CONTAINER "true"
 ENV PATH={{ $beatHome }}:$PATH
 
+# Add an init process, check the checksum to make sure it's a match
+RUN set -e ; \
+  TINI_VERSION='v0.19.0' ; \
+  TINI_BIN='tini-amd64' ; \
+  TINI_SHA256='93dcc18adc78c65a028a84799ecf8ad40c936fdfc5f2a57b1acda5a8117fa82c' ; \
+  curl --retry 8 -S -L -O "https://github.com/krallin/tini/releases/download/${TINI_VERSION}/${TINI_BIN}" ; \
+  echo "${TINI_SHA256} ${TINI_BIN}" | sha256sum -c - ; \
+  mv "${TINI_BIN}" /usr/bin/tini ; \
+  chmod +x /usr/bin/tini
+
 COPY docker-entrypoint /usr/local/bin/docker-entrypoint
 RUN chmod 755 /usr/local/bin/docker-entrypoint
 
@@ -80,5 +90,5 @@ EXPOSE {{ $port }}
 {{- end }}
 
 WORKDIR {{ $beatHome }}
-ENTRYPOINT ["/usr/local/bin/docker-entrypoint"]
+ENTRYPOINT ["/usr/bin/tini", "--", "/usr/local/bin/docker-entrypoint"]
 CMD ["-environment", "container"]