Use -mod=vendor for building

.circleci/config.yml

@@ -1,9 +1,10 @@
 version: 2
 jobs:
   test:
-    working_directory: /go/src/github.com/runatlantis/atlantis
     docker:
     - image: runatlantis/testing-env:latest
+      environment:
+        GOFLAGS: "-mod=vendor"
     steps:
     - checkout
     - run: make test-coverage
@@ -13,7 +14,6 @@ jobs:
     - run: make check-fmt
     - run: make check-lint
   e2e:
-    working_directory: /go/src/github.com/runatlantis/atlantis
     docker:
     - image: circleci/golang:1.12
       environment:
@@ -22,6 +22,7 @@ jobs:
         # that flag starts the download asynchronously so we'd have a race
         # condition.
         TERRAFORM_VERSION: 0.12.7
+        GOFLAGS: "-mod=vendor"
     steps:
     - checkout
     - run: make build-service
@@ -53,9 +54,10 @@ jobs:
 
   # Build and push 'latest' Docker tag.
   docker_master:
-    working_directory: /go/src/github.com/runatlantis/atlantis
     docker:
     - image: circleci/golang:1.12
+      environment:
+        GOFLAGS: "-mod=vendor"
     steps:
     - checkout
     - run: make build-service
@@ -75,9 +77,10 @@ jobs:
           fi
   # Build and push Docker tag.
   docker_tag:
-    working_directory: /go/src/github.com/runatlantis/atlantis
     docker:
     - image: circleci/golang:1.12
+      environment:
+        GOFLAGS: "-mod=vendor"
     steps:
     - checkout
     - run: make build-service

Makefile

@@ -64,7 +64,6 @@ check-lint: ## Run linter in CI/CD. If running locally use 'lint'
 	./bin/golangci-lint run
 
 check-fmt: ## Fail if not formatted
-	go get golang.org/x/tools/cmd/goimports
 	if [[ $$(goimports -l $$(find . -type f -name '*.go' ! -path "./vendor/*" ! -path "./server/static/bindata_assetfs.go" ! -path "**/mocks/*")) ]]; then exit 1; fi
 
 end-to-end-deps: ## Install e2e dependencies

testing/Dockerfile

@@ -11,3 +11,4 @@ RUN curl -LOks https://releases.hashicorp.com/terraform/${TERRAFORM_VERSION}/ter
     sudo unzip terraform_${TERRAFORM_VERSION}_linux_amd64.zip -d /usr/local/bin/tf/versions/${TERRAFORM_VERSION} && \
     sudo ln -s /usr/local/bin/tf/versions/${TERRAFORM_VERSION}/terraform /usr/local/bin/terraform && \
     rm terraform_${TERRAFORM_VERSION}_linux_amd64.zip
+RUN go get golang.org/x/tools/cmd/goimports