Add a Dockerfile that can build the collector along with an example. (#…

…256)

This makes sure that go tooling isn't required to play with a binary built from master. It works particularly well with docker-compose, where you can set the build context to https://github.com/open-telemetry/opentelemetry-collector-contrib.git and always be testing integrations against master with a single command.

**Link to tracking Issue:** fixes #236 

**Testing:** 
docker build / docker run

**Documentation:** Added the docker build command to the README

.circleci/config.yml

@@ -66,6 +66,12 @@ workflows:
           filters:
             tags:
               only: /.*/
+      - build-examples-tracing:
+          requires:
+            - setup-and-lint
+          filters:
+            tags:
+              only: /.*/
       - cross-compile:
           requires:
             - build
@@ -140,6 +146,16 @@ jobs:
           root: ~/
           paths: project/bin
 
+  build-examples-tracing:
+    docker:
+      - image: cimg/go:1.14
+    steps:
+      - attach_to_workspace
+      - setup_remote_docker
+      - run:
+          name: Build trace example
+          command: docker-compose -f examples/tracing/docker-compose.yml build
+
   cross-compile:
     executor: golang
     parallelism: 4

cmd/otelcontribcol/Dockerfile

@@ -5,4 +5,4 @@ FROM scratch
 COPY --from=certs /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
 COPY otelcontribcol /
 ENTRYPOINT ["/otelcontribcol"]
-EXPOSE 55678 55679
+EXPOSE 55680 55679

examples/tracing/Dockerfile

@@ -0,0 +1,15 @@
+FROM golang:1.14 AS build
+
+WORKDIR /src
+ADD . /src
+
+RUN make otelcontribcol
+
+FROM alpine:latest as certs
+RUN apk --update add ca-certificates
+
+FROM scratch
+COPY --from=certs /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+COPY --from=build /src/bin/otelcontribcol_linux_amd64 /otelcontribcol
+ENTRYPOINT ["/otelcontribcol"]
+EXPOSE 55680 55679

examples/tracing/README.md

@@ -0,0 +1,11 @@
+# OpenTelemetry Collector Demo
+
+This demo is a sample app to build the collector and exercise its tracing functionality.
+
+To build and run the demo, switch to this directory and run
+
+`docker-compose up`
+
+Hit `http://localhost:8081` in your browser or using something like cURL, and then open
+up `http://localhost:9411` or `http://localhost:16686` to search for the traces in the
+Zipkin or Jaeger UIs.

examples/tracing/docker-compose.yml

@@ -0,0 +1,56 @@
+version: "3"
+services:
+  # Jaeger
+  jaeger:
+    image: jaegertracing/all-in-one:latest
+    ports:
+      - "16686:16686"
+      - "14268"
+      - "14250"
+
+  #Zipkin
+  zipkin:
+    image: openzipkin/zipkin
+    container_name: zipkin
+    ports:
+      - 9411:9411
+
+  otel-collector:
+    build:
+      context: ../..
+      dockerfile: examples/tracing/Dockerfile
+    command: ["--config=/etc/otel-collector-config.yml"]
+    volumes:
+      - ./otel-collector-config.yml:/etc/otel-collector-config.yml
+    ports:
+      - "1888:1888"   # pprof extension
+      - "8888:8888"   # Prometheus metrics exposed by the collector
+      - "8889:8889"   # Prometheus exporter metrics
+      - "13133:13133" # health_check extension
+      - "9411"   # Zipkin receiver
+      - "55680:55679" # zpages extension
+    depends_on:
+      - jaeger
+      - zipkin
+
+  # Expose the frontend on http://localhost:8081
+  frontend:
+    image: openzipkin/example-sleuth-webmvc
+    command: Frontend
+    environment:
+      JAVA_OPTS: -Dspring.zipkin.baseUrl=http://otel-collector:9411
+    ports:
+      - 8081:8081
+    depends_on:
+      - otel-collector
+
+  # Expose the backend on http://localhost:9000
+  backend:
+    image: openzipkin/example-sleuth-webmvc
+    command: Backend
+    environment:
+      JAVA_OPTS: -Dspring.zipkin.baseUrl=http://otel-collector:9411
+    ports:
+      - 9000:9000
+    depends_on:
+      - otel-collector

examples/tracing/otel-collector-config.yml

@@ -0,0 +1,34 @@
+receivers:
+  otlp:
+    endpoint: 0.0.0.0:55680
+  zipkin:
+    endpoint: 0.0.0.0:9411
+
+exporters:
+  logging:
+
+  zipkin:
+    url: "http://zipkin:9411/api/v2/spans"
+    format: proto
+
+  jaeger_thrift:
+    url: "http://jaeger:14268/api/traces"
+
+processors:
+  batch:
+  queued_retry:
+
+extensions:
+  health_check:
+  pprof:
+    endpoint: :1888
+  zpages:
+    endpoint: :55679
+
+service:
+  extensions: [pprof, zpages, health_check]
+  pipelines:
+    traces:
+      receivers: [otlp, zipkin]
+      exporters: [zipkin, jaeger_thrift, logging]
+      processors: [batch, queued_retry]