From bc464c7cb899325783e8a0fccb8ae84080aa2654 Mon Sep 17 00:00:00 2001
From: Manuel de Brito Fontes <aledbf@gmail.com>
Date: Wed, 13 Sep 2017 20:04:20 -0300
Subject: [PATCH] Add example for nginx custom error pages

---
 images/custom-error-pages/Makefile            | 110 ++++++++++++++++++
 images/custom-error-pages/README.md           |   2 +
 images/custom-error-pages/main.go             |  94 +++++++++++++++
 images/custom-error-pages/rootfs/Dockerfile   |  21 ++++
 images/custom-error-pages/rootfs/www/404.html |   1 +
 images/custom-error-pages/rootfs/www/404.json |   1 +
 images/custom-error-pages/rootfs/www/4xx.html |   1 +
 images/custom-error-pages/rootfs/www/4xx.json |   1 +
 images/custom-error-pages/rootfs/www/500.html |   1 +
 images/custom-error-pages/rootfs/www/500.json |   1 +
 images/custom-error-pages/rootfs/www/5xx.html |   1 +
 images/custom-error-pages/rootfs/www/5xx.json |   1 +
 12 files changed, 235 insertions(+)
 create mode 100644 images/custom-error-pages/Makefile
 create mode 100644 images/custom-error-pages/README.md
 create mode 100644 images/custom-error-pages/main.go
 create mode 100755 images/custom-error-pages/rootfs/Dockerfile
 create mode 100644 images/custom-error-pages/rootfs/www/404.html
 create mode 100644 images/custom-error-pages/rootfs/www/404.json
 create mode 100644 images/custom-error-pages/rootfs/www/4xx.html
 create mode 100644 images/custom-error-pages/rootfs/www/4xx.json
 create mode 100644 images/custom-error-pages/rootfs/www/500.html
 create mode 100644 images/custom-error-pages/rootfs/www/500.json
 create mode 100644 images/custom-error-pages/rootfs/www/5xx.html
 create mode 100644 images/custom-error-pages/rootfs/www/5xx.json

diff --git a/images/custom-error-pages/Makefile b/images/custom-error-pages/Makefile
new file mode 100644
index 000000000..96b3d3479
--- /dev/null
+++ b/images/custom-error-pages/Makefile
@@ -0,0 +1,110 @@
+all: push
+
+BUILDTAGS=
+
+# Use the 0.0 tag for testing, it shouldn't clobber any release builds
+TAG?=0.1
+REGISTRY?=aledbf
+GOOS?=linux
+DOCKER?=gcloud docker --
+SED_I?=sed -i
+GOHOSTOS ?= $(shell go env GOHOSTOS)
+
+PKG=k8s.io/ingress/images/custom-error-pages
+
+ifeq ($(GOHOSTOS),darwin)
+  SED_I=sed -i ''
+endif
+
+REPO_INFO=$(shell git config --get remote.origin.url)
+
+ifndef COMMIT
+  COMMIT := git-$(shell git rev-parse --short HEAD)
+endif
+
+ARCH ?= $(shell go env GOARCH)
+GOARCH = ${ARCH}
+DUMB_ARCH = ${ARCH}
+
+BASEIMAGE?=alpine:3.6
+
+ALL_ARCH = amd64 arm arm64 ppc64le
+
+QEMUVERSION=v2.9.1
+
+IMGNAME = custom-error-pages
+IMAGE = $(REGISTRY)/$(IMGNAME)
+MULTI_ARCH_IMG = $(IMAGE)-$(ARCH)
+
+ifeq ($(ARCH),arm)
+    QEMUARCH=arm
+	GOARCH=arm
+endif
+ifeq ($(ARCH),arm64)
+        QEMUARCH=aarch64
+endif
+ifeq ($(ARCH),ppc64le)
+	QEMUARCH=ppc64le
+	GOARCH=ppc64le
+endif
+#ifeq ($(ARCH),s390x)
+#        QEMUARCH=s390x
+#endif
+
+TEMP_DIR := $(shell mktemp -d)
+
+DOCKERFILE := $(TEMP_DIR)/rootfs/Dockerfile
+
+all: all-container
+
+sub-container-%:
+	$(MAKE) ARCH=$* build container
+
+sub-push-%:
+	$(MAKE) ARCH=$* push
+
+all-container: $(addprefix sub-container-,$(ALL_ARCH))
+
+all-push: $(addprefix sub-push-,$(ALL_ARCH))
+
+container: .container-$(ARCH)
+.container-$(ARCH):
+	cp -r ./* $(TEMP_DIR)
+	$(SED_I) 's|BASEIMAGE|$(BASEIMAGE)|g' $(DOCKERFILE)
+	$(SED_I) "s|QEMUARCH|$(QEMUARCH)|g" $(DOCKERFILE)
+
+ifeq ($(ARCH),amd64)
+	# When building "normally" for amd64, remove the whole line, it has no part in the amd64 image
+	$(SED_I) "/CROSS_BUILD_/d" $(DOCKERFILE)
+else
+	# When cross-building, only the placeholder "CROSS_BUILD_" should be removed
+	# Register /usr/bin/qemu-ARCH-static as the handler for ARM binaries in the kernel
+	$(DOCKER) run --rm --privileged multiarch/qemu-user-static:register --reset
+	curl -sSL https://github.com/multiarch/qemu-user-static/releases/download/$(QEMUVERSION)/x86_64_qemu-$(QEMUARCH)-static.tar.gz | tar -xz -C $(TEMP_DIR)/rootfs
+	$(SED_I) "s/CROSS_BUILD_//g" $(DOCKERFILE)
+endif
+
+	$(DOCKER) build -t $(MULTI_ARCH_IMG):$(TAG) $(TEMP_DIR)/rootfs
+
+ifeq ($(ARCH), amd64)
+	# This is for to maintain the backward compatibility
+	$(DOCKER) tag $(MULTI_ARCH_IMG):$(TAG) $(IMAGE):$(TAG)
+endif
+
+push: .push-$(ARCH)
+.push-$(ARCH):
+	$(DOCKER) push $(MULTI_ARCH_IMG):$(TAG)
+ifeq ($(ARCH), amd64)
+	$(DOCKER) push $(IMAGE):$(TAG)
+endif
+
+clean:
+	$(DOCKER) rmi -f $(MULTI_ARCH_IMG):$(TAG) || true
+
+build: clean
+	CGO_ENABLED=0 GOOS=${GOOS} GOARCH=${GOARCH} go build -a -installsuffix cgo \
+		-ldflags "-s -w" \
+		-o ${TEMP_DIR}/rootfs/custom-error-pages ${PKG}/...
+
+release: all-container all-push
+	echo "done"
diff --git a/images/custom-error-pages/README.md b/images/custom-error-pages/README.md
new file mode 100644
index 000000000..3ee67e5d9
--- /dev/null
+++ b/images/custom-error-pages/README.md
@@ -0,0 +1,2 @@
+
+Example of Custom error pages for the NGINX Ingress controller
diff --git a/images/custom-error-pages/main.go b/images/custom-error-pages/main.go
new file mode 100644
index 000000000..88b709b6c
--- /dev/null
+++ b/images/custom-error-pages/main.go
@@ -0,0 +1,94 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"mime"
+	"net/http"
+	"os"
+	"strconv"
+)
+
+const (
+	FormatHeader = "X-Format"
+
+	CodeHeader = "X-Code"
+
+	ContentType = "Content-Type"
+)
+
+func main() {
+	path := "/www"
+	if os.Getenv("PATH") != "" {
+		path = os.Getenv("PATH")
+	}
+	http.HandleFunc("/", errorHandler(path))
+	http.ListenAndServe(fmt.Sprintf(":8080"), nil)
+}
+
+func errorHandler(path string) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		ext := "html"
+
+		format := r.Header.Get(FormatHeader)
+		if format == "" {
+			format = "text/html"
+			log.Printf("forma not specified. Using %v\n", format)
+		}
+
+		mediaType, _, _ := mime.ParseMediaType(format)
+		cext, err := mime.ExtensionsByType(mediaType)
+		if err != nil {
+			log.Printf("unexpected error reading media type extension: %v. Using %v\n", err, ext)
+		} else {
+			ext = cext[0]
+		}
+		w.Header().Set(ContentType, format)
+
+		errCode := r.Header.Get(CodeHeader)
+		code, err := strconv.Atoi(errCode)
+		if err != nil {
+			code = 404
+			log.Printf("unexpected error reading return code: %v. Using %v\n", err, code)
+		}
+		w.WriteHeader(code)
+
+		file := fmt.Sprintf("%v/%v%v", path, code, ext)
+		f, err := os.Open(file)
+		if err != nil {
+			log.Printf("unexpected error opening file: %v\n", err)
+			scode := strconv.Itoa(code)
+			file := fmt.Sprintf("%v/%cxx%v", path, scode[0], ext)
+			f, err := os.Open(file)
+			if err != nil {
+				log.Printf("unexpected error opening file: %v\n", err)
+				http.NotFound(w, r)
+				return
+			}
+			defer f.Close()
+			log.Printf("serving custom error response for code %v and format %v from file %v\n", code, format, file)
+			io.Copy(w, f)
+			return
+		}
+		defer f.Close()
+		log.Printf("serving custom error response for code %v and format %v from file %v\n", code, format, file)
+		io.Copy(w, f)
+	}
+}
diff --git a/images/custom-error-pages/rootfs/Dockerfile b/images/custom-error-pages/rootfs/Dockerfile
new file mode 100755
index 000000000..aaf60efb1
--- /dev/null
+++ b/images/custom-error-pages/rootfs/Dockerfile
@@ -0,0 +1,21 @@
+# Copyright 2017 The Kubernetes Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+FROM BASEIMAGE
+
+CROSS_BUILD_COPY qemu-QEMUARCH-static /usr/bin/
+
+COPY . /
+
+CMD ["/custom-error-pages"]
diff --git a/images/custom-error-pages/rootfs/www/404.html b/images/custom-error-pages/rootfs/www/404.html
new file mode 100644
index 000000000..0f00f93f5
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/404.html
@@ -0,0 +1 @@
+<span>The page you're looking for could not be found.</span>
\ No newline at end of file
diff --git a/images/custom-error-pages/rootfs/www/404.json b/images/custom-error-pages/rootfs/www/404.json
new file mode 100644
index 000000000..36f3e753e
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/404.json
@@ -0,0 +1 @@
+{ "message": "The page you're looking for could not be found" }
\ No newline at end of file
diff --git a/images/custom-error-pages/rootfs/www/4xx.html b/images/custom-error-pages/rootfs/www/4xx.html
new file mode 100644
index 000000000..05ba01769
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/4xx.html
@@ -0,0 +1 @@
+4xx html
\ No newline at end of file
diff --git a/images/custom-error-pages/rootfs/www/4xx.json b/images/custom-error-pages/rootfs/www/4xx.json
new file mode 100644
index 000000000..48246d04e
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/4xx.json
@@ -0,0 +1 @@
+4xx json
\ No newline at end of file
diff --git a/images/custom-error-pages/rootfs/www/500.html b/images/custom-error-pages/rootfs/www/500.html
new file mode 100644
index 000000000..68d7a7b52
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/500.html
@@ -0,0 +1 @@
+500 html
\ No newline at end of file
diff --git a/images/custom-error-pages/rootfs/www/500.json b/images/custom-error-pages/rootfs/www/500.json
new file mode 100644
index 000000000..9cad530c1
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/500.json
@@ -0,0 +1 @@
+500 json
\ No newline at end of file
diff --git a/images/custom-error-pages/rootfs/www/5xx.html b/images/custom-error-pages/rootfs/www/5xx.html
new file mode 100644
index 000000000..1bcb87780
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/5xx.html
@@ -0,0 +1 @@
+5xx html
\ No newline at end of file
diff --git a/images/custom-error-pages/rootfs/www/5xx.json b/images/custom-error-pages/rootfs/www/5xx.json
new file mode 100644
index 000000000..4703b68c6
--- /dev/null
+++ b/images/custom-error-pages/rootfs/www/5xx.json
@@ -0,0 +1 @@
+5xx json
\ No newline at end of file