Automate publishing of the dedicated kube-aws documentation site

* Print node.js version to debug when the script failed due to an incompatible node.js version
  * `nvm` for version-locking node.js isn't available in Travis CI's golang image

* Read the repo slug(`user/reponame`) from env vars so that we do not need to hard-code it

* Improve `make publish-docs` to support various cases
  * travis builds and local runs against a forked repo

.travis.yml

@@ -6,3 +6,8 @@ script:
   - make test-with-cover
 after_success:
   - bash <(curl -s https://codecov.io/bash)
+deploy:
+  provider: script
+  script: ci/publish-docs-as-bot.sh
+  on:
+    branch: master

Makefile

@@ -42,6 +42,15 @@ generate-docs: docs-dependencies
 serve-docs: docs-dependencies
 	gitbook serve
 
+# For publishing to the `git remote` named `mumoshu` linked to the repo url `git@github.com:mumoshu/kube-aws.git`, the env vars should be:
+#   REPO=mumoshu/kube-aws REMOTE=mumoshu make publish-docs
+# For publishing to the `git remote` named `origin` linked to the repo url `git@github.com:kubernetes-incubator/kube-aws.git`, the env vars should be:
+#   REPO=kubernetes-incubator/kube-aws REMOTE=origin make publish-docs
+# Or just:
+#   make publish-docs
+
 .PHONY: publish-docs
+publish-docs: REPO ?= kubernetes-incubator/kube-aws
+publish-docs: REMOTE ?= origin
 publish-docs: generate-docs
-	NODE_DEBUG=gh-pages gh-pages -d _book
+	NODE_DEBUG=gh-pages gh-pages -d _book -r git@github.com:$(REPO).git -o $(REMOTE)

ci/.gitignore

@@ -0,0 +1 @@
+kube-aws-bot-git-ssh-key*

ci/publish-docs-as-bot.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+
+set -ve
+
+# This script:
+# - assumes you've created a ssh key used by kube-aws-bot to ssh into github:
+#   https://help.github.com/articles/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent/
+# - utilizes Travis CI's file encryption feature for encrypting ssh keys
+
+# It requires the following command beforehand:
+#   $ gem install travis
+#   $ travis login --auto
+#   $ travis encrypt-file ci/kube-aws-bot-git-ssh-key --repo <your github user or organization>/kube-aws
+
+# And then change this line to the one output from the `travis encrypt-file` command above
+openssl aes-256-cbc -K $encrypted_514cf8442810_key -iv $encrypted_514cf8442810_iv -in kube-aws-bot-git-ssh-key.enc -out ci/kube-aws-bot-git-ssh-key -d
+
+## Prevent the following error:
+##   Permissions 0644 for '/home/travis/gopath/src/github.com/kubernetes-incubator/kube-aws/ci/kube-aws-bot-git-ssh-key' are too open.
+##   ...
+##   bad permissions: ignore key: /home/travis/gopath/src/github.com/kubernetes-incubator/kube-aws/ci/kube-aws-bot-git-ssh-key
+chmod 600 ci/kube-aws-bot-git-ssh-key
+
+# Finally run the following command to add the encrypted key to the git repo:
+#   $ git add kube-aws-bot-git-ssh-key.enc
+#   $   $ git commit -m '...'
+
+echo -e "Host github.com\n\tStrictHostKeyChecking no\nIdentityFile $(pwd)/ci/kube-aws-bot-git-ssh-key\n" >> ~/.ssh/config
+
+set +e
+ssh git@github.com
+status=$?
+set -e
+
+if [ $status -ne 1 ]; then
+  echo ssh connection check to github failed: ssh command exited with status $status 1>&2
+  exit 1
+fi
+
+echo Node.js $(node -v) is installed/being used
+
+REPO=$TRAVIS_REPO_SLUG make publish-docs