From f46a2b6ee151f8e5abdb446a21b8ad0fc603f764 Mon Sep 17 00:00:00 2001
From: Marcus Young <myoung34@my.apsu.edu>
Date: Tue, 12 Dec 2017 06:29:20 -0600
Subject: [PATCH 1/3] Modify to work with AWS ECS

---
 app/entrypoint.sh | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/app/entrypoint.sh b/app/entrypoint.sh
index 94fe0c92..94d6ec01 100755
--- a/app/entrypoint.sh
+++ b/app/entrypoint.sh
@@ -1,9 +1,13 @@
 #!/bin/bash
-# shellcheck disable=SC2155
+# shellcheck disable=SC2155,SC2002
 
-set -u
+set -e
 
-export CONTAINER_ID=$(cat /proc/self/cgroup | sed -nE 's/^.+docker[\/-]([a-f0-9]{64}).*/\1/p' | head -n 1)
+if [[ -n "${DOCKER_PROVIDER}" ]] && [[ "${DOCKER_PROVIDER,,}" == "aws" ]]; then
+  export CONTAINER_ID=$(cat "${ECS_CONTAINER_METADATA_FILE}" | grep ContainerID | sed 's/.*: "\(.*\)",/\1/g')
+else
+  export CONTAINER_ID=$(cat /proc/self/cgroup | sed -nE 's/^.+docker[\/-]([a-f0-9]{64}).*/\1/p' | head -n 1)
+fi
 
 if [[ -z "$CONTAINER_ID" ]]; then
     echo "Error: can't get my container ID !" >&2

From 61b2f29ded75ad01a1b07b8a90fa2bdbe181a39e Mon Sep 17 00:00:00 2001
From: Marcus Young <myoung34@my.apsu.edu>
Date: Tue, 12 Dec 2017 10:49:59 -0600
Subject: [PATCH 2/3] Minor PR tweaks

---
 app/entrypoint.sh | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/app/entrypoint.sh b/app/entrypoint.sh
index 94d6ec01..f4a6f287 100755
--- a/app/entrypoint.sh
+++ b/app/entrypoint.sh
@@ -1,12 +1,12 @@
 #!/bin/bash
-# shellcheck disable=SC2155,SC2002
+# shellcheck disable=SC2155
 
-set -e
+set -u
 
-if [[ -n "${DOCKER_PROVIDER}" ]] && [[ "${DOCKER_PROVIDER,,}" == "aws" ]]; then
-  export CONTAINER_ID=$(cat "${ECS_CONTAINER_METADATA_FILE}" | grep ContainerID | sed 's/.*: "\(.*\)",/\1/g')
+if [[ -n "${DOCKER_PROVIDER:-}" ]] && [[ "${DOCKER_PROVIDER,,}" == "aws" ]]; then
+  export CONTAINER_ID=$(grep ContainerID "${ECS_CONTAINER_METADATA_FILE}" | sed 's/.*: "\(.*\)",/\1/g')
 else
-  export CONTAINER_ID=$(cat /proc/self/cgroup | sed -nE 's/^.+docker[\/-]([a-f0-9]{64}).*/\1/p' | head -n 1)
+  export CONTAINER_ID=$(sed -nE 's/^.+docker[\/-]([a-f0-9]{64}).*/\1/p' /proc/self/cgroup | head -n 1)
 fi
 
 if [[ -z "$CONTAINER_ID" ]]; then

From 7ffa68161e74fda24d041d600b02c8664c023fb6 Mon Sep 17 00:00:00 2001
From: Marcus Young <myoung34@my.apsu.edu>
Date: Sat, 23 Dec 2017 12:30:31 -0600
Subject: [PATCH 3/3] Alternate way to set for AWS ECS

---
 README.md         |  4 ++++
 app/entrypoint.sh | 21 ++++++++++++++++-----
 2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 5c552474..ac7b736d 100644
--- a/README.md
+++ b/README.md
@@ -215,6 +215,10 @@ $ docker run -d \
 
 * `ACME_TOS_HASH` - Let´s you pass an alternative TOS hash to simp_le, to support other CA´s ACME implentation.
 
+* `DOCKER_PROVIDER` - Set this to change behavior on container ID retrieval. Optional. Current supported values:
+  * No value (empty, not  set): no change in behavior.
+  * `ecs` [Amazon ECS using ECS_CONTAINER_METADATA_FILE environment variable](http://docs.aws.amazon.com/AmazonECS/latest/developerguide/container-metadata.html)
+
 #### Examples:
 
 If you want other examples how to use this container, look at:
diff --git a/app/entrypoint.sh b/app/entrypoint.sh
index f4a6f287..10e0400d 100755
--- a/app/entrypoint.sh
+++ b/app/entrypoint.sh
@@ -3,11 +3,22 @@
 
 set -u
 
-if [[ -n "${DOCKER_PROVIDER:-}" ]] && [[ "${DOCKER_PROVIDER,,}" == "aws" ]]; then
-  export CONTAINER_ID=$(grep ContainerID "${ECS_CONTAINER_METADATA_FILE}" | sed 's/.*: "\(.*\)",/\1/g')
-else
-  export CONTAINER_ID=$(sed -nE 's/^.+docker[\/-]([a-f0-9]{64}).*/\1/p' /proc/self/cgroup | head -n 1)
-fi
+DOCKER_PROVIDER=${DOCKER_PROVIDER:-docker}
+
+case "${DOCKER_PROVIDER}" in
+ecs|ECS)
+    # AWS ECS. Enabled in /etc/ecs/ecs.config (http://docs.aws.amazon.com/AmazonECS/latest/developerguide/container-metadata.html)
+    if [[ -n "${ECS_CONTAINER_METADATA_FILE:-}" ]]; then
+      export CONTAINER_ID=$(grep ContainerID "${ECS_CONTAINER_METADATA_FILE}" | sed 's/.*: "\(.*\)",/\1/g')
+    else
+      echo "${DOCKER_PROVIDER} specified as 'ecs' but not available. See: http://docs.aws.amazon.com/AmazonECS/latest/developerguide/container-metadata.html"
+      exit 1
+    fi
+    ;;
+*)
+    export CONTAINER_ID=$(sed -nE 's/^.+docker[\/-]([a-f0-9]{64}).*/\1/p' /proc/self/cgroup | head -n 1)
+    ;;
+esac
 
 if [[ -z "$CONTAINER_ID" ]]; then
     echo "Error: can't get my container ID !" >&2