move handler into its own package

server/handler/try.go

@@ -0,0 +1,76 @@
+package handler
+
+import (
+	"net/http"
+	"strings"
+
+	"github.com/rs/zerolog"
+
+	"codeberg.org/codeberg/pages/html"
+	"codeberg.org/codeberg/pages/server/cache"
+	"codeberg.org/codeberg/pages/server/context"
+	"codeberg.org/codeberg/pages/server/gitea"
+	"codeberg.org/codeberg/pages/server/upstream"
+)
+
+// tryUpstream forwards the target request to the Gitea API, and shows an error page on failure.
+func tryUpstream(ctx *context.Context, giteaClient *gitea.Client,
+	mainDomainSuffix, trimmedHost string,
+	options *upstream.Options,
+	canonicalDomainCache cache.SetGetKey,
+) {
+	// check if a canonical domain exists on a request on MainDomain
+	if strings.HasSuffix(trimmedHost, mainDomainSuffix) {
+		canonicalDomain, _ := upstream.CheckCanonicalDomain(giteaClient, options.TargetOwner, options.TargetRepo, options.TargetBranch, "", string(mainDomainSuffix), canonicalDomainCache)
+		if !strings.HasSuffix(strings.SplitN(canonicalDomain, "/", 2)[0], string(mainDomainSuffix)) {
+			canonicalPath := ctx.Req.RequestURI
+			if options.TargetRepo != "pages" {
+				path := strings.SplitN(canonicalPath, "/", 3)
+				if len(path) >= 3 {
+					canonicalPath = "/" + path[2]
+				}
+			}
+			ctx.Redirect("https://"+canonicalDomain+canonicalPath, http.StatusTemporaryRedirect)
+			return
+		}
+	}
+
+	// add host for debugging
+	options.Host = string(trimmedHost)
+
+	// Try to request the file from the Gitea API
+	if !options.Upstream(ctx, giteaClient) {
+		html.ReturnErrorPage(ctx, "", ctx.StatusCode)
+	}
+}
+
+// tryBranch checks if a branch exists and populates the target variables. If canonicalLink is non-empty,
+// it will also disallow search indexing and add a Link header to the canonical URL.
+func tryBranch(log zerolog.Logger, ctx *context.Context, giteaClient *gitea.Client,
+	targetOptions *upstream.Options, canonicalLink bool,
+) (*upstream.Options, bool) {
+	if targetOptions.TargetOwner == "" || targetOptions.TargetRepo == "" {
+		log.Debug().Msg("tryBranch: owner or repo is empty")
+		return nil, false
+	}
+
+	// Replace "~" to "/" so we can access branch that contains slash character
+	// Branch name cannot contain "~" so doing this is okay
+	targetOptions.TargetBranch = strings.ReplaceAll(targetOptions.TargetBranch, "~", "/")
+
+	// Check if the branch exists, otherwise treat it as a file path
+	branchExist, _ := targetOptions.GetBranchTimestamp(giteaClient)
+	if !branchExist {
+		log.Debug().Msg("tryBranch: branch doesn't exist")
+		return nil, false
+	}
+
+	if canonicalLink {
+		// Hide from search machines & add canonical link
+		ctx.RespWriter.Header().Set("X-Robots-Tag", "noarchive, noindex")
+		ctx.RespWriter.Header().Set("Link", targetOptions.ContentWebLink(giteaClient)+"; rel=\"canonical\"")
+	}
+
+	log.Debug().Msg("tryBranch: true")
+	return targetOptions, true
+}