Add escape support and support Caddy as middleware

.github/workflows/non-regression.yml

@@ -0,0 +1,21 @@
+name: Build container and validate lint/tests
+
+on:
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  lint-and-tests:
+    name: Validate Go code linting
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.18
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v2
+      - name: tests
+        run: go test -v -race ./...

.github/workflows/plugins.yml

@@ -0,0 +1,34 @@
+name: Build and validate go-esi as plugins
+
+on:
+  - pull_request
+
+jobs:
+  build-caddy-validator:
+    name: Check that go-esi build as caddy module
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Add domain.com host to /etc/hosts
+        run: |
+          sudo echo "127.0.0.1 domain.com" | sudo tee -a /etc/hosts
+      -
+        name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.18
+      -
+        name: Checkout code
+        uses: actions/checkout@v2
+      -
+        name: Install xcaddy
+        run: go install github.com/caddyserver/xcaddy/cmd/xcaddy@latest
+      -
+        name: Build go-esi as caddy module
+        run: cd plugins/caddy && xcaddy build --with github.com/darkweak/go-esi/middleware/caddy=./ --with github.com/darkweak/go-esi@latest=../..
+      -
+        name: Run Caddy tests
+        run: cd plugins/caddy && go test -v ./...
+      -
+        name: Run detached caddy
+        run: cd plugins/caddy && ./caddy run &

.github/workflows/release.yml

@@ -0,0 +1,30 @@
+name: Build container and publish to docker hub
+
+on:
+  create:
+    tags: ["v*"]
+
+jobs:
+  generate-artifacts:
+    name: Deploy to goreleaser
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Set up Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.18
+      -
+        name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      -
+        name: Run GoReleaser
+        uses: goreleaser/goreleaser-action@v3
+        with:
+          version: latest
+          args: release --rm-dist
+          workdir: ./middleware/server
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.golangci.yml

@@ -0,0 +1,3 @@
+run:
+  timeout: 30s
+  issues-exit-code: 1

.goreleaser.yml

@@ -0,0 +1,33 @@
+before:
+  hooks:
+  - go mod download
+builds:
+- <<: &build_defaults
+    ldflags:
+      - -s -w
+  env:
+    - CGO_ENABLED=0
+  goos:
+    - linux
+    - darwin
+    - windows
+  goarch:
+    - 386
+    - amd64
+    - arm
+    - arm64
+  ignore:
+    - goos: windows
+      goarch: arm64
+archives:
+  -
+    replacements:
+      darwin: Darwin
+      linux: Linux
+      windows: Windows
+      386: i386
+      amd64: x86_64
+    format_overrides:
+      -
+        goos: windows
+        format: zip

Makefile

@@ -0,0 +1,7 @@
+.PHONY: lint run-caddy run-roadrunner
+
+lint: ## Run golangci-lint to ensure the code quality
+	docker run --rm -v $(PWD):/app -w /app golangci/golangci-lint golangci-lint run
+
+run-caddy: ## Build caddy binary
+	cd middleware/caddy && $(MAKE) build && $(MAKE) run

README.md

@@ -11,15 +11,37 @@ https://www.w3.org/TR/esi-lang/
 go get -u github.com/darkweak/go-esi
 ```
 
+## Usage
+```go
+import (
+    // ...
+    github.com/darkweak/go-esi/esi
+)
+
+//...
+
+func functionToParseESITags(b []byte, r *http.Request) []byte {
+    // Returns the parsed response.
+    res := esi.Parse(b, r)
+
+    //...
+    return res
+}
+```
+
 ## Available as middleware
-- [ ] Caddy
-- [ ] Træfik
-- [ ] Roadrunner
+- [x] Caddy
+
+### Caddy middleware
+```bash
+xcaddy build --with github.com/darkweak/go-esi/middleware/caddy
+```
+Refer to the [sample Caddyfile](https://github.com/darkweak/go-esi/blob/master/middleware/caddy/Caddyfile) to know how to configure that.
 
 ## TODO
 - [x] choose tag
 - [x] comment tag
-- [ ] escape tag
+- [x] escape tag
 - [x] include tag
 - [x] remove tag
 - [x] otherwise tag

esi.go

@@ -0,0 +1 @@
+package go_esi

esi/choose.go

@@ -5,49 +5,46 @@ import (
 	"regexp"
 )
 
-const (
-	choose    = "choose"
-	otherwise = "otherwise"
-	when      = "when"
-)
+const choose = "choose"
 
 var (
-	closeChoose   = regexp.MustCompile("</esi:choose>")
-	whenRg        = regexp.MustCompile(`(?s)<esi:when test="(.+?)">(.+?)</esi:when>`)
-	otherwiseRg   = regexp.MustCompile(`(?s)<esi:otherwise>(.+?)</esi:otherwise>`)
-	testAttribute = regexp.MustCompile(`test="(.+?)" ?>`)
+	closeChoose = regexp.MustCompile("</esi:choose>")
+	whenRg      = regexp.MustCompile(`(?s)<esi:when test="(.+?)">(.+?)</esi:when>`)
+	otherwiseRg = regexp.MustCompile(`(?s)<esi:otherwise>(.+?)</esi:otherwise>`)
 )
 
 type chooseTag struct {
 	*baseTag
 }
 
 // Input (e.g.
-//  <esi:choose>
-//    <esi:when test="$(HTTP_COOKIE{group})=='Advanced'">
-//        <esi:include src="http://www.example.com/advanced.html"/>
-//    </esi:when>
-//    <esi:when test="$(HTTP_COOKIE{group})=='Basic User'">
-//        <esi:include src="http://www.example.com/basic.html"/>
-//    </esi:when>
-//    <esi:otherwise>
-//        <esi:include src="http://www.example.com/new_user.html"/>
-//    </esi:otherwise>
-//  </esi:choose>
-//)
+// <esi:choose>
+//   <esi:when test="$(HTTP_COOKIE{group})=='Advanced'">
+//       <esi:include src="http://www.example.com/advanced.html"/>
+//   </esi:when>
+//   <esi:when test="$(HTTP_COOKIE{group})=='Basic User'">
+//       <esi:include src="http://www.example.com/basic.html"/>
+//   </esi:when>
+//   <esi:otherwise>
+//       <esi:include src="http://www.example.com/new_user.html"/>
+//   </esi:otherwise>
+// </esi:choose>
+// ).
 func (c *chooseTag) process(b []byte, req *http.Request) ([]byte, int) {
 	found := closeChoose.FindIndex(b)
 	if found == nil {
 		return nil, len(b)
 	}
-	c.length = found[1]
 
-	// first when esi tag
+	c.length = found[1]
 	tagIdxs := whenRg.FindAllSubmatch(b, -1)
+
 	var res []byte
+
 	for _, v := range tagIdxs {
 		if validateTest(v[1], req) {
 			res = Parse(v[2], req)
+
 			break
 		}
 	}
@@ -57,5 +54,5 @@ func (c *chooseTag) process(b []byte, req *http.Request) ([]byte, int) {
 		res = Parse(tagIdx[1], req)
 	}
 
-	return res, len(b)
+	return res, c.length
 }

esi/comment.go

@@ -13,13 +13,12 @@ type commentTag struct {
 	*baseTag
 }
 
-// Input (e.g. comment text="This is a comment." />)
+// Input (e.g. comment text="This is a comment." />).
 func (c *commentTag) process(b []byte, req *http.Request) ([]byte, int) {
 	found := closeComment.FindIndex(b)
 	if found == nil {
 		return nil, len(b)
 	}
-	c.length = found[1]
 
-	return []byte{}, len(b)
+	return []byte{}, found[1]
 }

esi/escape.go

@@ -1,7 +1,30 @@
 package esi
 
-import "regexp"
+import (
+	"net/http"
+	"regexp"
+)
 
-const escape = "escape"
+const escape = "<!--esi"
 
-var closeEscape = regexp.MustCompile("-->")
+var (
+	escapeRg    = regexp.MustCompile("<!--esi")
+	closeEscape = regexp.MustCompile("-->")
+)
+
+type escapeTag struct {
+	*baseTag
+}
+
+func (e *escapeTag) process(b []byte, req *http.Request) ([]byte, int) {
+	closeIdx := closeEscape.FindIndex(b)
+
+	if closeIdx == nil {
+		return nil, len(b)
+	}
+
+	e.length = closeIdx[1]
+	b = b[:closeIdx[0]]
+
+	return b, e.length
+}

esi/esi.go

@@ -20,6 +20,9 @@ func findTagName(b []byte) tag {
 			baseTag: newBaseTag(),
 		}
 	case escape:
+		return &escapeTag{
+			baseTag: newBaseTag(),
+		}
 	case include:
 		return &includeTag{
 			baseTag: newBaseTag(),
@@ -44,21 +47,33 @@ func Parse(b []byte, req *http.Request) []byte {
 	pointer := 0
 
 	for pointer < len(b) {
+		var escapeTag bool
+
 		next := b[pointer:]
 		tagIdx := esi.FindIndex(next)
 
+		if escIdx := escapeRg.FindIndex(next); escIdx != nil && (tagIdx == nil || escIdx[0] < tagIdx[0]) {
+			tagIdx = escIdx
+			tagIdx[1] = escIdx[0]
+			escapeTag = true
+		}
+
 		if tagIdx == nil {
 			break
 		}
 
 		esiPointer := tagIdx[1]
 		t := findTagName(next[esiPointer:])
 
+		if escapeTag {
+			esiPointer += 7
+		}
+
 		res, p := t.process(next[esiPointer:], req)
 		esiPointer += p
 
 		b = append(b[:pointer], append(next[:tagIdx[0]], append(res, next[esiPointer:]...)...)...)
-		pointer += len(res)
+		pointer += len(res) + tagIdx[0]
 	}
 
 	return b