feat(lib): Serverless output for static websites and Next.js

go.mod

@@ -18,6 +18,7 @@ require (
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/otiai10/copy v1.12.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/rogpeppe/go-internal v1.9.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect

go.sum

@@ -158,6 +158,8 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/moznion/go-optional v0.10.0 h1:YE42pzLDp6vc9zi/2hyaHYJesjahZEgFXEN1u5DMwMA=
 github.com/moznion/go-optional v0.10.0/go.mod h1:l3mLmsyp2bWTvWKjEm5MT7lo3g5MRlNIflxFB0XTASA=
+github.com/otiai10/copy v1.12.0 h1:cLMgSQnXBs1eehF0Wy/FAGsgDTDmAqFR7rQylBb1nDY=
+github.com/otiai10/copy v1.12.0/go.mod h1:rSaLseMUsZFFbsFGc7wCJnnkTAvdc5L6VWxPE4308Ww=
 github.com/pan93412/envexpander v1.1.0 h1:cf57P8BllM2CWfHO0eEKkpIoz0e44J94+H2Mh+hcUtw=
 github.com/pan93412/envexpander v1.1.0/go.mod h1:sBLOiYNNmCNyx+6z6L3Cegcs1MG0l7KXu8rhe41ZsM0=
 github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=

internal/nodejs/nextjs/function.go

@@ -0,0 +1,85 @@
+package nextjs
+
+import (
+	"encoding/json"
+	"fmt"
+	cp "github.com/otiai10/copy"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+// constructNextFunction will construct the first function page, used as symlinks for other function pages
+func constructNextFunction(zeaburOutputDir, firstFuncPage string) error {
+	p := path.Join(zeaburOutputDir, "functions", firstFuncPage+".func")
+
+	err := os.MkdirAll(p, 0755)
+	if err != nil {
+		return fmt.Errorf("create function dir: %w", err)
+	}
+
+	launcher, err := renderLauncher()
+	if err != nil {
+		return fmt.Errorf("render launcher: %w", err)
+	}
+
+	err = os.WriteFile(path.Join(p, "index.js"), []byte(launcher), 0644)
+	if err != nil {
+		return fmt.Errorf("write launcher: %w", err)
+	}
+
+	err = cp.Copy(".next", path.Join(p, ".next"))
+	if err != nil {
+		return fmt.Errorf("copy .next: %w", err)
+	}
+
+	err = cp.Copy("package.json", path.Join(p, "package.json"))
+	if err != nil {
+		return fmt.Errorf("copy package.json: %w", err)
+	}
+
+	outputNodeModulesDir := path.Join(p, "node_modules")
+	err = os.MkdirAll(outputNodeModulesDir, 0755)
+	if err != nil {
+		return fmt.Errorf("create node_modules dir: %w", err)
+	}
+
+	var deps []string
+	err = filepath.Walk(".next", func(path string, info os.FileInfo, err error) error {
+		if strings.HasSuffix(path, ".nft.json") {
+			type nftJson struct {
+				Files []string `json:"files"`
+			}
+			b, err := os.ReadFile(path)
+			if err != nil {
+				return fmt.Errorf("read nft.json: %w", err)
+			}
+			var nft nftJson
+			err = json.Unmarshal(b, &nft)
+			if err != nil {
+				return fmt.Errorf("unmarshal nft.json: %w", err)
+			}
+			for _, file := range nft.Files {
+				if !strings.Contains(file, "node_modules") {
+					continue
+				}
+				file = file[strings.Index(file, "node_modules"):]
+				deps = append(deps, file)
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		return fmt.Errorf("walk .next: %w", err)
+	}
+
+	for _, dep := range deps {
+		err = cp.Copy(dep, path.Join(p, dep))
+		if err != nil {
+			return fmt.Errorf("copy dep: %w", err)
+		}
+	}
+
+	return nil
+}

internal/nodejs/nextjs/launcher.go

@@ -0,0 +1,68 @@
+package nextjs
+
+import (
+	_ "embed"
+	"encoding/json"
+	"fmt"
+	"os"
+	"strings"
+	"text/template"
+)
+
+//go:embed launcher.js.tmpl
+var launcherTemplate string
+
+// getNextConfig read .next/required-server-files.json and return the config string that will be injected into launcher
+func getNextConfig() (string, error) {
+	rsf, err := os.ReadFile(".next/required-server-files.json")
+	if err != nil {
+		return "", fmt.Errorf("read required-server-files.json: %w", err)
+	}
+
+	type requiredServerFiles struct {
+		Config json.RawMessage `json:"config"`
+	}
+
+	var rs requiredServerFiles
+	err = json.Unmarshal(rsf, &rs)
+	if err != nil {
+		return "", fmt.Errorf("unmarshal required-server-files.json: %w", err)
+	}
+
+	var data map[string]interface{}
+	if err := json.Unmarshal(rs.Config, &data); err != nil {
+		return "", fmt.Errorf("unmarshal config: %w", err)
+	}
+
+	nextConfig, err := json.Marshal(data)
+	if err != nil {
+		return "", fmt.Errorf("marshal config: %w", err)
+	}
+
+	return string(nextConfig), nil
+}
+
+// renderLauncher will render the launcher.js template which used as the entrypoint of the serverless function
+func renderLauncher() (string, error) {
+	nextConfig, err := getNextConfig()
+	if err != nil {
+		return "", fmt.Errorf("get next config: %w", err)
+	}
+
+	tmpl, err := template.New("launcher").Parse(launcherTemplate)
+	if err != nil {
+		return "", fmt.Errorf("parse launcher template: %w", err)
+	}
+
+	type renderLauncherTemplateContext struct {
+		NextConfig string
+	}
+
+	var launcher strings.Builder
+	err = tmpl.Execute(&launcher, renderLauncherTemplateContext{NextConfig: nextConfig})
+	if err != nil {
+		return "", fmt.Errorf("render launcher template: %w", err)
+	}
+
+	return launcher.String(), nil
+}

internal/nodejs/nextjs/launcher.js.tmpl

@@ -0,0 +1,24 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+process.chdir(__dirname);
+process.env.NODE_ENV = 'production';
+process.env.__NEXT_PRIVATE_PREBUNDLED_REACT = "next"
+const NextServer = require('next/dist/server/next-server.js').default;
+const nextServer = new NextServer({
+	conf: {{ .NextConfig }},
+	dir: '.',
+	minimalMode: true,
+	customServer: false,
+});
+const requestHandler = nextServer.getRequestHandler();
+module.exports = async (req, res) => {
+	const { NodeNextRequest, NodeNextResponse}  = require('next/dist/server/base-http/node');
+	req = new NodeNextRequest(req)
+	res = new NodeNextResponse(res)
+	try {
+		await requestHandler(req, res);
+	} catch (err) {
+		console.error(err);
+		process.exit(1);
+	}
+};

internal/nodejs/nextjs/main.go

@@ -0,0 +1,138 @@
+package nextjs
+
+import (
+	_ "embed"
+	"encoding/json"
+	"fmt"
+	cp "github.com/otiai10/copy"
+	"github.com/zeabur/zbpack/internal/utils"
+	"github.com/zeabur/zbpack/pkg/types"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"text/template"
+)
+
+// TransformServerless will transform build output of Next.js app to the serverless build output format of Zeabur
+// It is trying to implement the same logic as build function of https://github.com/vercel/vercel/tree/main/packages/next/src/index.ts
+func TransformServerless(image, workdir string) error {
+	nextOutputDir := path.Join(workdir, ".next")
+	nextOutputServerPagesDir := path.Join(nextOutputDir, "server/pages")
+	zeaburOutputDir := path.Join(workdir, ".zeabur/output")
+
+	_ = os.RemoveAll(nextOutputDir)
+
+	err := utils.CopyFromImage(image, "/src/.next/.", nextOutputDir)
+	if err != nil {
+		return err
+	}
+
+	_ = os.RemoveAll(path.Join(workdir, ".zeabur"))
+
+	var serverlessFunctionPages []string
+	internalPages := []string{"_app.js", "_document.js", "_error.js"}
+	_ = filepath.Walk(nextOutputServerPagesDir, func(path string, info os.FileInfo, err error) error {
+		if strings.HasSuffix(path, ".js") {
+			for _, internalPage := range internalPages {
+				if strings.HasSuffix(path, internalPage) {
+					return nil
+				}
+			}
+			funcPath := strings.TrimPrefix(path, nextOutputServerPagesDir)
+			funcPath = strings.TrimSuffix(funcPath, ".js")
+			serverlessFunctionPages = append(serverlessFunctionPages, funcPath)
+		}
+		return nil
+	})
+
+	var staticPages []string
+	_ = filepath.Walk(nextOutputServerPagesDir, func(path string, info os.FileInfo, err error) error {
+		if strings.HasSuffix(path, ".html") {
+			filePath := strings.TrimPrefix(path, nextOutputServerPagesDir)
+			staticPages = append(staticPages, filePath)
+		}
+		return nil
+	})
+
+	err = os.MkdirAll(path.Join(zeaburOutputDir, "static"), 0755)
+	if err != nil {
+		return fmt.Errorf("create static dir: %w", err)
+	}
+
+	err = cp.Copy(path.Join(nextOutputDir, "static"), path.Join(zeaburOutputDir, "static/_next/static"))
+	if err != nil {
+		return fmt.Errorf("copy static dir: %w", err)
+	}
+
+	err = cp.Copy(path.Join(workdir, "public"), path.Join(zeaburOutputDir, "static"))
+	if err != nil {
+		return fmt.Errorf("copy public dir: %w", err)
+	}
+
+	nextConfig, err := getNextConfig()
+	if err != nil {
+		return fmt.Errorf("get next config: %w", err)
+	}
+
+	tmpl, err := template.New("launcher").Parse(launcherTemplate)
+	if err != nil {
+		return fmt.Errorf("parse launcher template: %w", err)
+	}
+
+	type renderLauncherTemplateContext struct {
+		NextConfig string
+	}
+
+	var launcher strings.Builder
+	err = tmpl.Execute(&launcher, renderLauncherTemplateContext{NextConfig: nextConfig})
+	if err != nil {
+		return fmt.Errorf("render launcher template: %w", err)
+	}
+
+	// if there is any serverless function page, create the first function page and symlinks for other function pages
+	if len(serverlessFunctionPages) > 0 {
+
+		// create the first function page
+		err = constructNextFunction(zeaburOutputDir, serverlessFunctionPages[0])
+		if err != nil {
+			return fmt.Errorf("construct next function: %w", err)
+		}
+
+		// create symlinks for other function pages
+		for i, p := range serverlessFunctionPages {
+			if i == 0 {
+				continue
+			}
+
+			funcPath := path.Join(zeaburOutputDir, "functions", p+".func")
+
+			err = os.MkdirAll(path.Dir(funcPath), 0755)
+			if err != nil {
+				return fmt.Errorf("create function dir: %w", err)
+			}
+
+			err = os.Symlink(path.Join(zeaburOutputDir, "functions", serverlessFunctionPages[0]+".func"), funcPath)
+			if err != nil {
+				return fmt.Errorf("create symlink: %w", err)
+			}
+		}
+	}
+
+	// copy static pages which is rendered by Next.js at build time, so they will be served as static files
+	for _, p := range staticPages {
+		err = cp.Copy(path.Join(nextOutputDir, "server/pages", p), path.Join(zeaburOutputDir, "static", p))
+		if err != nil {
+			return fmt.Errorf("copy static page: %w", err)
+		}
+	}
+
+	cfg := types.ZeaburOutputConfig{Containerized: false, Routes: make([]types.ZeaburOutputConfigRoute, 0)}
+	cfgBytes, err := json.Marshal(cfg)
+	if err != nil {
+		return fmt.Errorf("marshal config: %w", err)
+	}
+
+	err = os.WriteFile(path.Join(zeaburOutputDir, "config.json"), cfgBytes, 0644)
+	return nil
+}