build: ditch verifiers on make (#4679)

This commit ditches running verifiers automatically when just building
the server. It retains the verifiers when running tests.

There is very little point to running the verifiers each time a
developer builds the library but has no intent of running the tests.
They're expensive in time; this commit halves the build time on my
system, from 57 seconds to 29 seconds. This is because verifiers updates
the libraries from GitHub each time, which is slightly wasteful.
Additionally, computing cyclomatic complexity is expensive
computationally and isn't necessary to build the library.

Additionally, this allows the library to be built offline. It no longer
requires internet to run make.

Makefile

@@ -4,7 +4,7 @@ LDFLAGS := $(shell go run buildscripts/gen-ldflags.go)
 
 BUILD_LDFLAGS := '$(LDFLAGS)'
 
-all: install
+all: build
 
 checks:
 	@echo "Check deps"
@@ -19,7 +19,7 @@ getdeps: checks
 	@echo "Installing misspell" && go get -u github.com/client9/misspell/cmd/misspell
 	@echo "Installing ineffassign" && go get -u github.com/gordonklaus/ineffassign
 
-verifiers: vet fmt lint cyclo spelling
+verifiers: getdeps vet fmt lint cyclo spelling
 
 vet:
 	@echo "Running $@"
@@ -45,8 +45,6 @@ cyclo:
 	@${GOPATH}/bin/gocyclo -over 100 cmd
 	@${GOPATH}/bin/gocyclo -over 100 pkg
 
-build: getdeps verifiers $(UI_ASSETS)
-
 deadcode:
 	@${GOPATH}/bin/deadcode
 
@@ -55,7 +53,9 @@ spelling:
 	@${GOPATH}/bin/misspell -error `find pkg/`
 	@${GOPATH}/bin/misspell -error `find docs/`
 
-test: build
+# Builds minio, runs the verifiers then runs the tests.
+check: test
+test: verifiers build
 	@echo "Running all minio testing"
 	@go test $(GOFLAGS) .
 	@go test $(GOFLAGS) github.com/minio/minio/cmd...
@@ -65,9 +65,10 @@ coverage: build
 	@echo "Running all coverage for minio"
 	@./buildscripts/go-coverage.sh
 
-gomake-all: build
-	@echo "Installing minio at $(GOPATH)/bin/minio"
-	@CGO_ENABLED=0 go build --ldflags $(BUILD_LDFLAGS) -o $(GOPATH)/bin/minio
+# Builds minio locally.
+build:
+	@echo "Building minio to $(PWD)/minio ..."
+	@CGO_ENABLED=0 go build --ldflags $(BUILD_LDFLAGS) -o $(PWD)/minio
 
 pkg-add:
 	@echo "Adding new package $(PKG)"
@@ -84,7 +85,11 @@ pkg-remove:
 pkg-list:
 	@$(GOPATH)/bin/govendor list
 
-install: gomake-all
+# Builds minio and installs it to $GOPATH/bin.
+install: build
+	@echo "Installing minio at $(GOPATH)/bin/minio ..."
+	@cp $(PWD)/minio $(GOPATH)/bin/minio
+	@echo "Check 'minio -h' for help."
 
 release: verifiers
 	@MINIO_RELEASE=RELEASE ./buildscripts/build.sh