pages-server/main.go

142 lines
5.4 KiB
Go

// Package main is the new Codeberg Pages server, a solution for serving static pages from Gitea repositories.
//
// Mapping custom domains is not static anymore, but can be done with DNS:
//
// 1) add a "domains.txt" text file to your repository, containing the allowed domains, separated by new lines. The
// 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):
// 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
// for "example.org" (if your provider allows ALIAS or similar records):
// example.org IN ALIAS codeberg.page.
//
// Certificates are generated, updated and cleaned up automatically via Let's Encrypt through a TLS challenge.
package main
import (
"bytes"
"crypto/tls"
"fmt"
"log"
"net"
"net/http"
"os"
"time"
_ "embed"
"github.com/valyala/fasthttp"
)
// MainDomainSuffix specifies the main domain (starting with a dot) for which subdomains shall be served as static
// pages, or used for comparison in CNAME lookups. Static pages can be accessed through
// https://{owner}.{MainDomain}[/{repo}], with repo defaulting to "pages".
var MainDomainSuffix = []byte("." + envOr("PAGES_DOMAIN", "codeberg.page"))
// GiteaRoot specifies the root URL of the Gitea instance, without a trailing slash.
var GiteaRoot = []byte(envOr("GITEA_ROOT", "https://codeberg.org"))
//go:embed 404.html
var NotFoundPage []byte
// BrokenDNSPage will be shown (with a redirect) when trying to access a domain for which no DNS CNAME record exists.
var BrokenDNSPage = envOr("REDIRECT_BROKEN_DNS", "https://docs.codeberg.org/pages/custom-domains/")
// RawDomain specifies the domain from which raw repository content shall be served in the following format:
// https://{RawDomain}/{owner}/{repo}[/{branch|tag|commit}/{version}]/{filepath...}
// (set to []byte(nil) to disable raw content hosting)
var RawDomain = []byte(envOr("RAW_DOMAIN", "raw.codeberg.org"))
// RawInfoPage will be shown (with a redirect) when trying to access RawDomain directly (or without owner/repo/path).
var RawInfoPage = envOr("REDIRECT_RAW_INFO", "https://docs.codeberg.org/pages/raw-content/")
// AllowedCorsDomains lists the domains for which Cross-Origin Resource Sharing is allowed.
var AllowedCorsDomains = [][]byte{
RawDomain,
[]byte("fonts.codeberg.org"),
[]byte("design.codeberg.org"),
}
// BlacklistedPaths specifies forbidden path prefixes for all Codeberg Pages.
var BlacklistedPaths = [][]byte{
[]byte("/.well-known/acme-challenge/"),
}
// IndexPages lists pages that may be considered as index pages for directories.
var IndexPages = []string{
"index.html",
}
// main sets up and starts the web server.
func main() {
// Make sure MainDomain has a trailing dot, and GiteaRoot has no trailing slash
if !bytes.HasPrefix(MainDomainSuffix, []byte{'.'}) {
MainDomainSuffix = append([]byte{'.'}, MainDomainSuffix...)
}
GiteaRoot = bytes.TrimSuffix(GiteaRoot, []byte{'/'})
// Use HOST and PORT environment variables to determine listening address
address := fmt.Sprintf("%s:%s", envOr("HOST", "[::]"), envOr("PORT", "443"))
log.Printf("Listening on https://%s", address)
// Enable compression by wrapping the handler() method with the compression function provided by FastHTTP
compressedHandler := fasthttp.CompressHandlerBrotliLevel(handler, fasthttp.CompressBrotliBestSpeed, fasthttp.CompressBestSpeed)
server := &fasthttp.Server{
Handler: compressedHandler,
DisablePreParseMultipartForm: false,
MaxRequestBodySize: 0,
NoDefaultServerHeader: true,
NoDefaultDate: true,
ReadTimeout: 30 * time.Second, // needs to be this high for ACME certificates with ZeroSSL & HTTP-01 challenge
Concurrency: 1024 * 32, // TODO: adjust bottlenecks for best performance with Gitea!
MaxConnsPerIP: 100,
}
// Setup listener and TLS
listener, err := net.Listen("tcp", address)
if err != nil {
log.Fatalf("Couldn't create listener: %s", err)
}
listener = tls.NewListener(listener, tlsConfig)
setupCertificates()
if os.Getenv("ENABLE_HTTP_SERVER") == "true" {
go (func() {
challengePath := []byte("/.well-known/acme-challenge/")
err := fasthttp.ListenAndServe("[::]:80", func(ctx *fasthttp.RequestCtx) {
if bytes.HasPrefix(ctx.Path(), challengePath) {
challenge, ok := challengeCache.Get(string(TrimHostPort(ctx.Host())) + "/" + string(bytes.TrimPrefix(ctx.Path(), challengePath)))
if !ok || challenge == nil {
ctx.SetStatusCode(http.StatusNotFound)
ctx.SetBodyString("no challenge for this token")
}
ctx.SetBodyString(challenge.(string))
} else {
ctx.Redirect("https://" + string(ctx.Host()) + string(ctx.RequestURI()), http.StatusMovedPermanently)
}
})
if err != nil {
log.Fatalf("Couldn't start HTTP server: %s", err)
}
})()
}
// Start the web server
err = server.Serve(listener)
if err != nil {
log.Fatalf("Couldn't start server: %s", err)
}
}
// envOr reads an environment variable and returns a default value if it's empty.
func envOr(env string, or string) string {
if v := os.Getenv(env); v != "" {
return v
}
return or
}