Prepare for dependency vendoring.

- Add helper script to simplify glide usage.
- Add validation script for unwanted changes to vendoring.
- Relax/tighten up .{git,docker}ignore to cover vendored files properly.
- .validate: Protect from unbound variable in case of nounset setting.
- Install more recent hg version in the build container.
- Remove glide installation steps from Dockerfile.
- Update documentation.

.dockerignore

@@ -1,5 +1,3 @@
-dist/
-vendor/
-!dist/traefik
-site/
-**/*.test
+/dist/
+!/dist/traefik
+/site/

.github/CONTRIBUTING.md

@@ -2,7 +2,7 @@
 
 ### Building
 
-You need either [Docker](https://github.com/docker/docker) and `make` (Method 1), or `go` and `glide` (Method 2) in order to build traefik.
+You need either [Docker](https://github.com/docker/docker) and `make` (Method 1), or `go` (Method 2) in order to build traefik. For changes to its dependencies, the `glide` dependency management tool and `glide-vc` plugin are required.
 
 #### Method 1: Using `Docker` and `Makefile`
 
@@ -26,7 +26,7 @@ $ ls dist/
 traefik*
 ```
 
-#### Method 2: Using `go` and `glide`
+#### Method 2: Using `go`
 
 ###### Setting up your `go` environment
 
@@ -42,20 +42,25 @@ This can be verified via `$ go env`
 - You will want to add those 2 export lines to your `.bashrc` or `.bash_profile`
 - You need `go-bindata` to be able to use `go generate` command (needed to build) : `$ go get github.com/jteeuwen/go-bindata/...` (Please note, the ellipses are required)
 
-###### Setting up your `glide` environment
+#### Setting up `glide` and `glide-vc` for dependency management
 
+- Glide is not required for building; however, it is necessary to modify dependencies (i.e., add, update, or remove third-party packages)
 - Glide can be installed either via homebrew: `$ brew install glide` or via the official glide script: `$ curl https://glide.sh/get | sh`
+- The glide plugin `glide-vc` must be installed from source: `go get github.com/sgotti/glide-vc`
 
-The idea behind `glide` is the following :
+If you want to add a dependency, use `$ glide get` to have glide put it into the vendor folder and update the glide manifest/lock files (`glide.yaml` and `glide.lock`, respectively). A following `glide-vc` run should be triggered to trim down the size of the vendor folder. The final result must be committed into VCS.
 
-- when checkout(ing) a project, run `$ glide install -v` from the cloned directory to install
-  (`go get …`) the dependencies in your `GOPATH`.
-- if you need another dependency, import and use it in
-  the source, and run `$ glide get github.com/Masterminds/cookoo` to save it in
-  `vendor` and add it to your `glide.yaml`.
+Dependencies for the integration tests in the `integration` folder are managed in a separate `integration/glide.yaml` file using the same toolset.
+
+Care must be taken to choose the right arguments to `glide` when dealing with either main or integration test dependencies, or otherwise risk ending up with a broken build. For that reason, the helper script `script/glide.sh` encapsulates the gory details and conveniently calls `glide-vc` as well. Call it without parameters for basic usage instructions.
+
+Here's a full example:
 
 ```bash
-$ glide install --strip-vendor
+# install the new main dependency github.com/foo/bar and minimize vendor size
+$ ./script/glide.sh get github.com/foo/bar
+# install another dependency, this time for the integration tests
+$ ( cd integration && ../script/glide.sh get github.com/baz/quuz )
 # generate (Only required to integrate other components such as web dashboard)
 $ go generate
 # Standard go build
@@ -105,14 +110,12 @@ TESTFLAGS="-check.f MyTestSuite.*Test" make test-integration
 
 More: https://labix.org/gocheck
 
-##### Method 2: `go` and `glide`
+##### Method 2: `go`
 
 - Tests can be run from the cloned directory, by `$ go test ./...` which should return `ok` similar to:
 ```
 ok      _/home/vincent/src/github/vdemeester/traefik    0.004s
 ```
-- Note that `$ go test ./...` will run all tests (including the ones in the vendor directory for the dependencies that glide have fetched). If you only want to run the tests for traefik use `$ go test $(glide novendor)` instead.
-
 
 ### Documentation
 

.gitignore

@@ -1,15 +1,13 @@
 /dist
-gen.go
+/autogen/gen.go
 .idea
 .intellij
 *.iml
-traefik
-traefik.toml
-*.test
-vendor/
-static/
+/traefik
+/traefik.toml
+/static/
 .vscode/
-site/
+/site/
 *.log
 *.exe
 .DS_Store

Makefile

@@ -45,7 +45,7 @@ test-integration: build ## run the integration tests
 	$(DOCKER_RUN_TRAEFIK) ./script/make.sh generate binary test-integration
 
 validate: build  ## validate gofmt, golint and go vet
-	$(DOCKER_RUN_TRAEFIK) ./script/make.sh  validate-glide validate-gofmt validate-govet validate-golint validate-misspell
+	$(DOCKER_RUN_TRAEFIK) ./script/make.sh  validate-glide validate-gofmt validate-govet validate-golint validate-misspell validate-vendor
 
 build: dist
 	docker build $(DOCKER_BUILD_ARGS) -t "$(TRAEFIK_DEV_IMAGE)" -f build.Dockerfile .

build.Dockerfile

@@ -1,10 +1,18 @@
 FROM golang:1.7
 
+# Install a more recent version of mercurial to avoid mismatching results
+# between glide run on a decently updated host system and the build container.
+RUN awk '$1 ~ "^deb" { $3 = $3 "-backports"; print; exit }' /etc/apt/sources.list > /etc/apt/sources.list.d/backports.list && \
+  DEBIAN_FRONTEND=noninteractive apt-get update && \
+  DEBIAN_FRONTEND=noninteractive apt-get install -t jessie-backports --yes --no-install-recommends mercurial=3.9.1-1~bpo8+1 && \
+  rm -fr /var/lib/apt/lists/
+
 RUN go get github.com/jteeuwen/go-bindata/... \
 && go get github.com/golang/lint/golint \
 && go get github.com/kisielk/errcheck \
 && go get github.com/client9/misspell/cmd/misspell \
-&& go get github.com/mattfarina/glide-hash
+&& go get github.com/mattfarina/glide-hash \
+&& go get github.com/sgotti/glide-vc
 
 # Which docker version to test on
 ARG DOCKER_VERSION=1.10.3
@@ -24,13 +32,4 @@ RUN mkdir -p /usr/local/bin \
     | tar -xzC /usr/local/bin --transform 's#^.+/##x'
 
 WORKDIR /go/src/github.com/containous/traefik
-
-COPY glide.yaml glide.yaml
-COPY glide.lock glide.lock
-RUN glide install -v
-
-COPY integration/glide.yaml integration/glide.yaml
-COPY integration/glide.lock integration/glide.lock
-RUN cd integration && glide install
-
 COPY . /go/src/github.com/containous/traefik

script/.validate

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-if [ -z "$VALIDATE_UPSTREAM" ]; then
+if [ -z "${VALIDATE_UPSTREAM:-}" ]; then
 	# this is kind of an expensive check, so let's not do this twice if we
 	# are running more than one validate bundlescript
 

script/glide.sh

@@ -0,0 +1,119 @@
+#!/bin/bash
+set -o errexit
+set -o pipefail
+set -o nounset
+
+####
+### Helper script for glide[-vc] to handle specifics for the Traefik repo.
+##
+# In particular, the 'integration/' directory contains its own set of
+# glide-managed dependencies which must not have its nested vendor folder
+# stripped. Depending on where the script is called from, it will do the Right
+# Thing.
+#
+
+CWD="$(pwd)"; readonly CWD
+GLIDE_ARGS=()
+GLIDE_VC_ARGS=(
+  '--use-lock-file'       # `glide list` seems to miss test dependencies, e.g., github.com/mattn/go-shellwords
+  '--only-code'
+  '--no-tests'
+)
+
+usage() {
+  echo "usage: $(basename "$0") install | update | get <package> | trim
+install: Install all dependencies and trim the vendor folder afterwards (alternative command: i).
+update:  Update all dependencies and trim the vendor folder afterwards (alternative command: up).
+get:     Add a dependency and trim the vendor folder afterwards.
+trim:    Trim the vendor folder only, do not install or update dependencies.
+
+The current working directory must contain a glide.yaml file." >&2
+}
+
+is_integration_dir() {
+  [[ "$(basename ${CWD})" = 'integration' ]]
+}
+
+if ! is_integration_dir; then
+  GLIDE_ARGS+=('--strip-vendor' '--skip-test')
+fi
+
+if ! type glide > /dev/null 2>&1; then
+  echo "glide not found in PATH." >&2
+  exit 1
+fi
+
+if ! type glide-vc > /dev/null 2>&1; then
+  echo "glide-vc not found in PATH." >&2
+  exit 1
+fi
+
+if [[ ! -e "${CWD}/glide.yaml" ]]; then
+  echo "no glide.yaml file found in the current working directory" >&2
+  exit 1
+fi
+
+if [[ $# -lt 1 ]]; then
+  echo "missing command" >&2
+  usage
+  exit 1
+fi
+
+readonly glide_command="$1"
+shift
+
+skip_glide_command=
+case "${glide_command}" in
+  'install' | 'i')
+    if [[ $# -ne 0 ]]; then
+      echo "surplus parameters given" >&2
+      usage
+      exit 1
+    fi
+    ;;
+
+  'update' | 'up')
+    if [[ $# -ne 0 ]]; then
+      echo "surplus parameters given" >&2
+      usage
+      exit 1
+    fi
+    ;;
+
+  'get')
+    if [[ $# -ne 1 ]]; then
+      echo 'insufficient/surplus arguments given for "get" command' >&2
+      usage
+      exit 1
+    fi
+    GLIDE_ARGS=("$1" "${GLIDE_ARGS[@]}")
+    shift
+    ;;
+
+  'trim')
+    if [[ $# -ne 0 ]]; then
+      echo "surplus parameters given" >&2
+      usage
+      exit 1
+    fi
+    skip_glide_command=yes
+    ;;
+
+  *)
+    echo "unknown command: ${glide_command}" >&2
+    usage
+    exit 1
+esac
+readonly skip_glide_command
+
+if [[ -z "${skip_glide_command}" ]]; then
+  # Use parameter substitution to account for an empty glide arguments array
+  # that would otherwise lead to an "unbound variable" error due to the nounset
+  # option.
+  GLIDE_ARGS=("${GLIDE_ARGS+"${GLIDE_ARGS[@]}"}")
+  echo "running: glide ${glide_command} ${GLIDE_ARGS[*]}"
+  glide ${glide_command} ${GLIDE_ARGS[*]}
+fi
+
+echo "trimming vendor folder using: glide-vc ${GLIDE_VC_ARGS[*]}"
+glide-vc ${GLIDE_VC_ARGS[*]}

script/validate-glide

@@ -6,7 +6,7 @@ if grep -q "$(glide-hash)" glide.lock; then
 	echo 'Congratulations! glide.lock is unchanged.'
 else
 	{
-		echo "Error: glide.lock has been manually changed. Don't do this. Use glide up instead."
+		echo "Error: glide.lock has been manually changed. Don't do this. Use script/glide.sh up instead."
 		echo
 	} >&2
 	false

script/validate-gofmt

@@ -3,7 +3,7 @@
 source "$(dirname "$BASH_SOURCE")/.validate"
 
 IFS=$'\n'
-files=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^vendor' || true) )
+files=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^\(integration/\)\?vendor/' || true) )
 unset IFS
 
 badFiles=()

script/validate-golint

@@ -3,7 +3,7 @@
 source "$(dirname "$BASH_SOURCE")/.validate"
 
 IFS=$'\n'
-files=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^vendor/\|autogen' || true) )
+files=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^\(integration/\)\?vendor/\|autogen' || true) )
 unset IFS
 
 errors=()

script/validate-govet

@@ -3,7 +3,7 @@
 source "$(dirname "$BASH_SOURCE")/.validate"
 
 IFS=$'\n'
-files=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^vendor/' || true) )
+files=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^\(integration/\)\?vendor/' || true) )
 unset IFS
 
 errors=()

script/validate-misspell

@@ -3,7 +3,7 @@
 source "$(dirname "$BASH_SOURCE")/.validate"
 
 IFS=$'\n'
-src=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^vendor/\|autogen' || true) )
+src=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^\(integration/\)\?vendor/\|autogen' || true) )
 docs=( $(validate_diff --diff-filter=ACMR --name-only -- 'docs/*.md') )
 unset IFS
 files=("${src[@]}" "${docs[@]}")

script/validate-vendor

@@ -0,0 +1,37 @@
+#!/bin/bash
+set -o errexit
+set -o pipefail
+set -o nounset
+
+SCRIPTDIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"; export SCRIPTDIR
+source "${SCRIPTDIR}/.validate"
+
+# Iterate over all directories containing vendor folders.
+for dir in . integration; do
+	vendor_dir="${dir}/vendor/"
+	IFS=$'\n' files=( $(validate_diff --diff-filter=ACMR --name-only -- ${vendor_dir} || true) )
+
+	if [[ ${#files[@]} -gt 0 ]]; then
+		# We run glide install to and see if we have a diff afterwards
+		echo "checking ${vendor_dir} for unintentional changes..."
+		(
+		cd ${dir}
+		"${SCRIPTDIR}/glide.sh" install
+		)
+		# Let see if the working directory is clean
+		diffs="$(git status --porcelain -- ${vendor_dir} 2>/dev/null)"
+		if [[ "$diffs" ]]; then
+			{
+				echo "The result of 'glide install' for vendor directory '${dir}' differs"
+				echo
+				echo "$diffs"
+				echo
+				echo 'Please vendor your package(s) with script/glide.sh.'
+				echo
+			} >&2
+			exit 2
+		fi
+	fi
+done
+
+echo 'Congratulations! All vendoring changes are done the right way.'