Support architecture targeted builds (aws#837)

This reworks much of the Makefile and, to a lesser extent, the
Dockerfiles for building the CNI plugins for other platforms.

Additional clean up work is included as well as this was combed
through to support these builds.

Including:

- ARCH resolver to identify the ARCH (GOARCH styled) to pass around
- Updated ARCH and GOARCH references throughout to support
  against other ARCHes
- Make base container build appropriately for ARCH
  - Docker explicit multiarch references in targets and Dockerfiles
  - Updated related container images to allow testing where possible
- Eliminate ./tmp usage with tar unpacking from a pipe
- Clean up and consistent call sites all around
   - Reconciled image naming
   - Updated stale golang images references
- Added docstrings for reference

.circleci/config.yml

@@ -5,28 +5,46 @@ orbs:
  aws-cli: circleci/[email protected]
  k8s: circleci/[email protected]
 
-jobs:
- build:
+references:
+ build_job: &build
  docker:
  - image: circleci/golang:1.13-stretch
  working_directory: /go/src/github.com/{{ORG_NAME}}/{{REPO_NAME}}
- environment:
+ environment: &env
  GO111MODULE: "on"
  steps:
  - checkout
  - run: go get -u golang.org/x/lint/golint
  - run: go get -u golang.org/x/tools/cmd/goimports
  - run: make check-format
- - run: make build-linux
- - run: make lint
+ - run: make build-linux "ARCH=$ARCH"
+ # TODO: Make lint a hard-check once baselined
+ - run: make lint LINT_FLAGS=
  - run: make vet
- - run: make unit-test
+ # TODO: Enable architecture specific unit-test when Circle CI supports it!
+ - run: make unit-test ARCH=amd64
+
+jobs:
+ build_x86_64:
+ <<: *build
+ environment:
+ <<: *env
+ # Target the GOARCH for x86_64
+ ARCH: amd64
+
+ build_aarch64:
+ <<: *build
+ environment:
+ <<: *env
+ # Target the GOARCH for aarch64
+ ARCH: arm64
+
  integration_test:
  docker:
  - image: circleci/golang:1.13-stretch
  working_directory: /go/src/github.com/{{ORG_NAME}}/{{REPO_NAME}}
  environment:
- GO111MODULE: "on"
+ <<: *env
  RUN_CONFORMANCE: "true"
  steps:
  - checkout
@@ -47,11 +65,13 @@ workflows:
  version: 2
  check:
  jobs:
- - build
+ - build_x86_64
+ - build_aarch64
  - hold:
  type: approval
  requires:
- - build
+ - build_x86_64
+ - build_aarch64
  - integration_test:
  requires:
  - hold

.dockerignore

@@ -1,4 +1,6 @@
 aws-cni
 aws-k8s-agent
+cni-metrics-helper
+grpc-health-probe
 portmap
-cni-metrics-helper/cni-metrics-helper
+routed-eni-cni-plugin

.gitignore

@@ -7,6 +7,6 @@ verify-network
 .idea/
 *.iml
 .DS_Store
-cni-metrics-helper/cni-metrics-helper
 portmap
 grpc-health-probe
+cni-metrics-helper