Support access branch that contains slash character (#102)

So we can access branch that contain slash like `branch/name` with `username.codeberg.page/repo/@branch~name/`.

Branch name cannot contain `~` character but it can be in a HTTP URL, so replace the `~` from URL to `/` could be a valid solution to me.

Resolve #101

Co-authored-by: Gary Wang <wzc782970009@gmail.com>
Reviewed-on: https://codeberg.org/Codeberg/pages-server/pulls/102
Reviewed-by: 6543 <6543@noreply.codeberg.org>
Co-authored-by: Gary Wang <blumia@noreply.codeberg.org>
Co-committed-by: Gary Wang <blumia@noreply.codeberg.org>

README.md

@@ -18,7 +18,8 @@ Mapping custom domains is not static anymore, but can be done with DNS:
 first line will be the canonical domain/URL; all other occurrences will be redirected to it.
 
 2) add a CNAME entry to your domain, pointing to `[[{branch}.]{repo}.]{owner}.codeberg.page` (repo defaults to
-"pages", "branch" defaults to the default branch if "repo" is "pages", or to "pages" if "repo" is something else):
+"pages", "branch" defaults to the default branch if "repo" is "pages", or to "pages" if "repo" is something else.
+If the branch name contains slash characters, you need to replace "/" in the branch name to "~"):
 	`www.example.org. IN CNAME main.pages.example.codeberg.page.`
 
 3) if a CNAME is set for "www.example.org", you can redirect there from the naked domain by adding an ALIAS record

integration/get_test.go

@@ -49,6 +49,16 @@ func TestGetContent(t *testing.T) {
 	assert.EqualValues(t, "text/html; charset=utf-8", resp.Header.Get("Content-Type"))
 	assert.True(t, getSize(resp.Body) > 1000)
 	assert.Len(t, resp.Header.Get("ETag"), 42)
+
+	// access branch name contains '/'
+	resp, err = getTestHTTPSClient().Get("https://blumia.localhost.mock.directory:4430/pages-server-integration-tests/@docs~main/")
+	assert.NoError(t, err)
+	if !assert.EqualValues(t, http.StatusOK, resp.StatusCode) {
+		t.FailNow()
+	}
+	assert.EqualValues(t, "text/html; charset=utf-8", resp.Header.Get("Content-Type"))
+	assert.True(t, getSize(resp.Body) > 100)
+	assert.Len(t, resp.Header.Get("ETag"), 42)
 }
 
 func TestCustomDomain(t *testing.T) {

server/handler.go

@@ -89,6 +89,10 @@ func Handler(mainDomainSuffix, rawDomain []byte,
 				return false
 			}
 
+			// Replace "~" to "/" so we can access branch that contains slash character
+			// Branch name cannot contain "~" so doing this is okay
+			branch = strings.ReplaceAll(branch, "~", "/")
+
 			// Check if the branch exists, otherwise treat it as a file path
 			branchTimestampResult := upstream.GetBranchTimestamp(giteaClient, targetOwner, repo, branch, branchTimestampCache)
 			if branchTimestampResult == nil {