add Dockerfile that allows configuration through environment variables

Dockerfile

@@ -0,0 +1,14 @@
+FROM alpine:3.4
+
+RUN apk --update upgrade \
+ && apk add curl ca-certificates \
+ && update-ca-certificates \
+ && rm -rf /var/cache/apk/*
+
+COPY ldr /usr/bin/
+COPY docker-entrypoint.sh /usr/bin/
+
+ENTRYPOINT ["docker-entrypoint.sh"]
+
+EXPOSE 8030
+CMD ["ldr"]

Dockerfile-build

@@ -0,0 +1,7 @@
+FROM alpine:3.4
+
+RUN apk --update upgrade \
+ && apk add go godep \
+ && rm -rf /var/cache/apk/*
+
+WORKDIR /build

README.md

@@ -128,4 +128,57 @@ We have done extensive load tests on the relay proxy in AWS / EC2. We have also
 
 * If using an Elastic Load Balancer in front of the relay proxy, you may need to [pre-warm](https://aws.amazon.com/articles/1636185810492479) the load balancer whenever connections to the relay proxy are cycled. This might happen when you deploy a large number of new servers that connect to the proxy, or upgrade the relay proxy itself.
 
-
+Docker
+-------
+
+To build the ld-relay container:
+
+        $ docker build -t ld-relay-build -f Dockerfile-build . # create the build container image
+        $ docker run -v $(pwd):/build -t -i -e CGO_ENABLED=0 -e GOOS=linux ld-relay-build godep go build -a -installsuffix cgo -o ldr # create the ldr binary
+        $ docker build -t ld-relay . # build the ld-relay container image
+        $ docker rmi ld-relay-build # remove the build container image that is no longer needed
+
+To run a single environment, without Redis:
+
+        $ docker run --name ld-relay -e LD_ENV_test="sdk-test-apiKey" ld-relay
+
+To run multiple environments, without Redis:
+
+        $ docker run --name ld-relay -e LD_ENV_test="sdk-test-apiKey" -e LD_ENV_prod="sdk-prod-apiKey" ld-relay
+
+To run a single environment, with Redis:
+
+        $ docker run --name redis redis:alpine
+        $ docker run --name ld-relay --link redis:redis -e USE_REDIS=1 -e LD_ENV_test="sdk-test-apiKey" ld-relay
+
+To run multiple environment, with Redis:
+
+        $ docker run --name redis redis:alpine
+        $ docker run --name ld-relay --link redis:redis -e USE_REDIS=1 -e LD_ENV_test="sdk-test-apiKey" -e LD_PREFIX_test="ld:default:test" -e LD_ENV_prod="sdk-prod-apiKey" -e LD_PREFIX_prod="ld:default:prod" ld-relay
+
+
+Docker Environment Variables
+-------
+
+`LD_ENV_${environment}`: At least one `LD_ENV_${environment}` variable is recommended.  The value should be the api key for that specific environment.  Multiple environments can be listed
+
+`LD_PREFIX_${environment}`: This variable is optional.  Configures a Redis prefix for that specific environment.  Multiple environments can be listed
+
+`USE_REDIS`: This variable is optional.  If set to 1, Redis configuration will be added
+
+`REDIS_HOST`: This variable is optional.  Sets the hostname of the Redis server.  If linked to a redis container that sets `REDIS_PORT` to `tcp://172.17.0.2:6379`, `REDIS_HOST` will use this value as the default.  If not, the default value is `redis`
+
+`REDIS_PORT`: This variable is optional.  Sets the port of the Redis server.  If linked to a redis container that sets `REDIS_PORT` to `REDIS_PORT=tcp://172.17.0.2:6379`, `REDIS_PORT` will use this value as the default.  If not, the defualt value is `6379`
+
+`REDIS_TTL`: This variable is optional.  Sets the TTL in milliseconds, defaults to `30000`
+
+`USE_EVENTS`: This variable is optional.  If set to 1, enables event buffering
+
+`EVENTS_HOST`: This variable is optional.  URI of the LaunchDarkly events endpoint, defaults to `https://events.launchdarkly.com`
+
+`EVENTS_SEND`: This variable is optional.  Defaults to `true`
+
+`EVENTS_FLUSH_INTERVAL`: This variable is optional.  Sets how often events are flushed, defaults to `5` (seconds)
+
+`EVENTS_SAMPLING_INTERVAL`: This variable is optional.  Defaults to `10000`
+

circle.yml

@@ -1,3 +1,7 @@
+machine:
+  services:
+    - docker
+
 dependencies:
   pre:
     - rm -rf ~/.go_workspace/src/github.com/launchdarkly/ld-relay
@@ -17,9 +21,17 @@ dependencies:
 test:
   override:
     - godep go test
+    - docker build -t ld-relay-build -f Dockerfile-build .
+    - docker run --rm -v `pwd`:/build -t -i -e CGO_ENABLED=0 -e GOOS=linux ld-relay-build godep go build -a -installsuffix cgo -o ldr
+    - docker build -t "ld-relay:$CIRCLE_BUILD_NUM" .
 
 deployment:
-  s3:
+  branch:
     branch: /.*/
     commands:
+      - ./scripts/upload_to_dockerhub.sh
       - ./scripts/upload_to_s3.sh
+  tag:
+    tag: /.*/
+    commands:
+      - ./scripts/upload_to_dockerhub.sh

docker-entrypoint.sh

@@ -0,0 +1,62 @@
+#!/bin/sh
+if [ ! -f /etc/ld-relay.conf ]; then
+# only create /etc/ld-relay.conf if it doesn't exist already
+
+if ! env | grep -q LD_ENV_ ; then
+  echo "WARNING: at least one LD_ENV_ should be set" >&2
+fi
+
+echo "
+[main]
+streamUri = \"${STREAM_URI:-https://stream.launchdarkly.com}\"
+baseUri = \"${BASE_URI:-https://app.launchdarkly.com}\"
+exitOnError = ${EXIT_ON_ERROR:-false}
+port = ${PORT:-8030}
+heartbeatIntervalSecs = ${HEARTBEAT_INTERVAL:-15}
+" > /etc/ld-relay.conf
+
+if [ "$USE_REDIS" = 1 ]; then
+if echo "$REDIS_PORT" | grep -q 'tcp://'; then
+  # REDIS_PORT gets set to tcp://$docker_ip:6379 when linking to a redis container
+  # default to using those values if they exist
+  REDIS_HOST_PART="${REDIS_PORT%:*}"
+  REDIS_HOST="${REDIS_HOST_PART##*/}"
+  REDIS_PORT="${REDIS_PORT##*:}"
+fi
+
+echo "
+[redis]
+host = \"${REDIS_HOST:-redis}\"
+port = ${REDIS_PORT:-6379}
+localTtl = ${REDIS_TTL:-30000}
+" >> /etc/ld-relay.conf
+fi
+
+if [ "$USE_EVENTS" = 1 ]; then
+echo "
+[events]
+eventsUri = \"${EVENTS_HOST:-https://events.launchdarkly.com}\"
+sendEvents = ${EVENTS_SEND:-true}
+flushIntervalSecs = ${EVENTS_FLUSH_INTERVAL:-5}
+samplingInterval = ${EVENTS_SAMPLING_INTERVAL:-0}
+capacity = ${EVENTS_CAPACITY:-10000}
+" >> /etc/ld-relay.conf
+fi
+
+for environment in $(env | grep LD_ENV_ ); do
+env_name="$(echo "$environment" | sed 's/^LD_ENV_//' | cut -d'=' -f1)"
+env_key="$(eval echo "\$$(echo "$environment" | cut -d'=' -f1)")"
+env_prefix="$(eval echo "\$LD_PREFIX_${env_name}")"
+
+echo "
+[environment \"$env_name\"]
+apiKey = \"$env_key\"" >> /etc/ld-relay.conf
+
+if [ -n "$env_prefix" ]; then
+echo "prefix = \"$env_prefix\"" >> /etc/ld-relay.conf
+fi
+done
+
+fi
+
+exec "$@"

scripts/upload_to_dockerhub.sh

@@ -0,0 +1,30 @@
+#!/bin/sh
+
+set -e
+
+if [ -n "$CIRCLE_TAG" ]; then
+  TAG="$CIRCLE_TAG"
+elif
+  TAG="$CIRCLE_BRANCH"
+fi
+
+if [ -z "$TAG" ]; then
+  echo "Skipping: unable to determine branch or tag"
+  exit
+fi
+
+if [ -z "$DOCKER_USERNAME" ] || [ -z "$DOCKER_PASSWORD" ] || [ -z "$DOCKER_REPO" ]; then
+  echo "Skipping: DOCKER_USERNAME, DOCKER_PASSWORD, DOCKER_REPO environment variables not set"
+  exit
+fi
+
+# dockerhub requires an email address, but doesn't use it for anything
+echo "[email protected]" | docker login -u="$DOCKER_USERNAME" -p="$DOCKER_PASSWORD"
+docker tag "ld-relay:$CIRCLE_BUILD_NUM" "$DOCKER_REPO:$TAG"
+docker push "$DOCKER_REPO:$TAG"
+
+if [ "$TAG" = "master" ]; then
+  # tag the master branch as latest
+  docker tag "$DOCKER_REPO:$TAG" "$DOCKER_REPO:latest" 
+  docker push "$DOCKER_REPO:latest"
+fi

scripts/upload_to_s3.sh

@@ -1,5 +1,9 @@
 #/bin/bash
 set -e
+if [ -z "$bucket" ]; then
+  echo "Missing S3 credentials, skipping upload"
+  exit
+fi
 REV=$(git rev-parse HEAD | cut -c1-6)
 VERSION=2.2.0.${REV}
 ls ${CIRCLE_ARTIFACTS}/${VERSION}