Merge pull request #7 from ipfs-shipyard/jj-remove-force

Remove forced redirects support

README.md

@@ -7,10 +7,10 @@ Currently this is a subset of Netlify's [redirects format](https://www.netlify.c
 The details of the supported functionality are still in flux and will eventually be included in a [spec](https://github.com/ipfs/specs).
 
 ## Format
-Currently only supports `from`, `to`, `status` and `force`.
+Currently only supports `from`, `to` and `status`.
 
 ```
-from to [status][!]
+from to [status]
 ```
 
 ## Example
@@ -39,9 +39,6 @@ from to [status][!]
 
 # Proxying
 /api/*  https://api.example.com/:splat  200
-
-# Forced redirect, even if the from path exists
-/app/*  /app/index.html  200!
 ```
 
 ---

go.mod

@@ -5,6 +5,7 @@ go 1.17
 require (
 	github.com/pkg/errors v0.9.1
 	github.com/tj/assert v0.0.3
+	github.com/ucarion/urlpath v0.0.0-20200424170820-7ccc79b76bbb
 )
 
 require (

go.sum

@@ -10,6 +10,8 @@ github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/tj/assert v0.0.3 h1:Df/BlaZ20mq6kuai7f5z2TvPFiwC3xaWJSDQNiIS3Rk=
 github.com/tj/assert v0.0.3/go.mod h1:Ne6X72Q+TB1AteidzQncjw9PabbMp4PBMZ1k+vd1Pvk=
+github.com/ucarion/urlpath v0.0.0-20200424170820-7ccc79b76bbb h1:Ywfo8sUltxogBpFuMOFRrrSifO788kAFxmvVw31PtQQ=
+github.com/ucarion/urlpath v0.0.0-20200424170820-7ccc79b76bbb/go.mod h1:ikPs9bRWicNw3S7XpJ8sK/smGwU9WcSVU3dy9qahYBM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

redirects.go

@@ -3,12 +3,14 @@ package redirects
 
 import (
 	"bufio"
+	"fmt"
 	"io"
 	"net/url"
 	"strconv"
 	"strings"
 
 	"github.com/pkg/errors"
+	"github.com/ucarion/urlpath"
 )
 
 // A Rule represents a single redirection or rewrite rule.
@@ -29,10 +31,6 @@ type Rule struct {
 	// When proxying this field is ignored.
 	//
 	Status int
-
-	// Force is used to force a rewrite or redirect even
-	// when a response (or static file) is present.
-	Force bool
 }
 
 // IsRewrite returns true if the rule represents a rewrite (status 200).
@@ -81,11 +79,11 @@ func Parse(r io.Reader) (rules []Rule, err error) {
 
 		// missing dst
 		if len(fields) <= 1 {
-			return nil, errors.Wrapf(err, "missing destination path: %q", line)
+			return nil, fmt.Errorf("missing destination path: %q", line)
 		}
 
 		if len(fields) > 3 {
-			return nil, errors.Wrapf(err, "must match format `from to [status][!]`")
+			return nil, fmt.Errorf("must match format `from to [status][!]`")
 		}
 
 		// src and dst
@@ -97,13 +95,12 @@ func Parse(r io.Reader) (rules []Rule, err error) {
 
 		// status
 		if len(fields) > 2 {
-			code, force, err := parseStatus(fields[2])
+			code, err := parseStatus(fields[2])
 			if err != nil {
 				return nil, errors.Wrapf(err, "parsing status %q", fields[2])
 			}
 
 			rule.Status = code
-			rule.Force = force
 		}
 
 		rules = append(rules, rule)
@@ -118,13 +115,29 @@ func ParseString(s string) ([]Rule, error) {
 	return Parse(strings.NewReader(s))
 }
 
-// parseStatus returns the status code and force when "!" suffix is present.
-func parseStatus(s string) (code int, force bool, err error) {
+// parseStatus returns the status code.
+func parseStatus(s string) (code int, err error) {
 	if strings.HasSuffix(s, "!") {
-		force = true
-		s = strings.Replace(s, "!", "", -1)
+		// See https://docs.netlify.com/routing/redirects/rewrites-proxies/#shadowing
+		return -1, fmt.Errorf("forced redirects (or \"shadowing\") are not supported by IPFS gateways")
 	}
 
 	code, err = strconv.Atoi(s)
-	return
+	return code, err
+}
+
+// ReplacePlaceholders replaces all placeholders from the match in the provided string.
+func ReplacePlaceholders(to string, match urlpath.Match) string {
+	if len(match.Params) > 0 {
+		for key, value := range match.Params {
+			to = strings.ReplaceAll(to, ":"+key, value)
+		}
+	}
+
+	return to
+}
+
+// ReplaceSplat replaces all splats from the match in the provided string.
+func ReplaceSplat(to string, match urlpath.Match) string {
+	return strings.ReplaceAll(to, ":splat", match.Trailing)
 }

redirects_example_test.go

@@ -30,9 +30,6 @@ func Example() {
 
 		# Proxying
 		/api/*  https://api.example.com/:splat  200
-
-		# Forcing
-		/app/*  /app/index.html  200!
   `))
 
 	enc := json.NewEncoder(os.Stdout)
@@ -43,68 +40,52 @@ func Example() {
 	//   {
 	//     "From": "/home",
 	//     "To": "/",
-	//     "Status": 301,
-	//     "Force": false
+	//     "Status": 301
 	//   },
 	//   {
 	//     "From": "/blog/my-post.php",
 	//     "To": "/blog/my-post",
-	//     "Status": 301,
-	//     "Force": false
+	//     "Status": 301
 	//   },
 	//   {
 	//     "From": "/news",
 	//     "To": "/blog",
-	//     "Status": 301,
-	//     "Force": false
+	//     "Status": 301
 	//   },
 	//   {
 	//     "From": "/google",
 	//     "To": "https://www.google.com",
-	//     "Status": 301,
-	//     "Force": false
+	//     "Status": 301
 	//   },
 	//   {
 	//     "From": "/home",
 	//     "To": "/",
-	//     "Status": 301,
-	//     "Force": false
+	//     "Status": 301
 	//   },
 	//   {
 	//     "From": "/my-redirect",
 	//     "To": "/",
-	//     "Status": 302,
-	//     "Force": false
+	//     "Status": 302
 	//   },
 	//   {
 	//     "From": "/pass-through",
 	//     "To": "/index.html",
-	//     "Status": 200,
-	//     "Force": false
+	//     "Status": 200
 	//   },
 	//   {
 	//     "From": "/ecommerce",
 	//     "To": "/store-closed",
-	//     "Status": 404,
-	//     "Force": false
+	//     "Status": 404
 	//   },
 	//   {
 	//     "From": "/*",
 	//     "To": "/index.html",
-	//     "Status": 200,
-	//     "Force": false
+	//     "Status": 200
 	//   },
 	//   {
 	//     "From": "/api/*",
 	//     "To": "https://api.example.com/:splat",
-	//     "Status": 200,
-	//     "Force": false
-	//   },
-	//   {
-	//     "From": "/app/*",
-	//     "To": "/app/index.html",
-	//     "Status": 200,
-	//     "Force": true
+	//     "Status": 200
 	//   }
 	// ]
 }

redirects_test.go

@@ -1,6 +1,7 @@
 package redirects
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/tj/assert"
@@ -56,3 +57,13 @@ func TestRule_IsRewrite(t *testing.T) {
 		assert.False(t, r.IsRewrite())
 	})
 }
+
+func TestParse(t *testing.T) {
+	t.Run("with illegal force", func(t *testing.T) {
+		_, err := Parse(strings.NewReader(`
+		/home / 301!
+		`))
+
+		assert.Error(t, err, "forced redirects should return an error")
+	})
+}