Refactor embed FS build (#963)

main.go

@@ -1,15 +1,9 @@
 package main
 
 import (
-	"embed"
-
 	"github.com/esm-dev/esm.sh/server"
 )
 
-//go:embed README.md
-//go:embed server/embed
-var fs embed.FS
-
 func main() {
-	server.Serve(&fs)
+	server.Serve()
 }

server/build.go

@@ -15,7 +15,7 @@ import (
 	"strconv"
 	"strings"
 
-	npm_replacements "github.com/esm-dev/esm.sh/server/npm-replacements"
+	"github.com/esm-dev/esm.sh/server/npm_replacements"
 	"github.com/esm-dev/esm.sh/server/storage"
 	esbuild "github.com/evanw/esbuild/pkg/api"
 	"github.com/ije/gox/set"
@@ -911,7 +911,7 @@ func (ctx *BuildContext) buildModule(analyzeMode bool) (meta *BuildMeta, include
 		"Buffer":               "__Buffer$",
 		"process":              "__Process$",
 		"setImmediate":         "__setImmediate$",
-		"clearImmediate":       "clearTimeout",
+		"clearImmediate":       "__clearImmediate$",
 		"require.resolve":      "__rResolve$",
 		"process.env.NODE_ENV": fmt.Sprintf(`"%s"`, nodeEnv),
 	}
@@ -1141,18 +1141,66 @@ REBUILD:
 						header.WriteByte('\n')
 					}
 				}
-				if ids.Has("__global$") {
-					header.WriteString(`var __global$ = globalThis || (typeof window !== "undefined" ? window : self);`)
-					header.WriteByte('\n')
-				}
 				if ids.Has("__setImmediate$") {
-					header.WriteString(`var __setImmediate$ = (cb, ...args) => setTimeout(cb, 0, ...args);`)
-					header.WriteByte('\n')
+					if ctx.args.external.Has("node:timers") {
+						header.WriteString(`import { setImmediate as __setImmediate$ } from "node:timers";`)
+						header.WriteByte('\n')
+					} else if ctx.isBrowserTarget() {
+						var excluded bool
+						if len(ctx.pkgJson.Browser) > 0 {
+							if name, ok := ctx.pkgJson.Browser["timers"]; ok {
+								excluded = name == ""
+							} else if name, ok := ctx.pkgJson.Browser["node:timers"]; ok {
+								excluded = name == ""
+							}
+						}
+						if !excluded {
+							header.WriteString(`import { setImmediate as __setImmediate$ } from "/node/timers.mjs";`)
+							header.WriteByte('\n')
+							imports.Add("/node/timers.mjs")
+						}
+					} else if ctx.target == "denonext" {
+						header.WriteString(`import { setImmediate as __setImmediate$ } from "node:timers";`)
+						header.WriteByte('\n')
+					} else if ctx.target == "deno" {
+						header.WriteString(`import { setImmediate as __setImmediate$ } from "https://deno.land/[email protected]/node/timers.ts";`)
+						header.WriteByte('\n')
+					}
+				}
+				if ids.Has("__clearImmediate$") {
+					if ctx.args.external.Has("node:timers") {
+						header.WriteString(`import { clearImmediate as __clearImmediate$ } from "node:timers";`)
+						header.WriteByte('\n')
+					} else if ctx.isBrowserTarget() {
+						var excluded bool
+						if len(ctx.pkgJson.Browser) > 0 {
+							if name, ok := ctx.pkgJson.Browser["timers"]; ok {
+								excluded = name == ""
+							} else if name, ok := ctx.pkgJson.Browser["node:timers"]; ok {
+								excluded = name == ""
+							}
+						}
+						if !excluded {
+							header.WriteString(`import { clearImmediate as __clearImmediate$ } from "/node/timers.mjs";`)
+							header.WriteByte('\n')
+							imports.Add("/node/timers.mjs")
+						}
+					} else if ctx.target == "denonext" {
+						header.WriteString(`import { clearImmediate as __clearImmediate$ } from "node:timers";`)
+						header.WriteByte('\n')
+					} else if ctx.target == "deno" {
+						header.WriteString(`import { clearImmediate as __clearImmediate$ } from "https://deno.land/[email protected]/node/timers.ts";`)
+						header.WriteByte('\n')
+					}
 				}
 				if ids.Has("__rResolve$") {
 					header.WriteString(`var __rResolve$ = p => p;`)
 					header.WriteByte('\n')
 				}
+				if ids.Has("__global$") {
+					header.WriteString(`var __global$ = globalThis || (typeof window !== "undefined" ? window : self);`)
+					header.WriteByte('\n')
+				}
 			}
 
 			// apply cjs requires

server/cache.go

@@ -27,21 +27,25 @@ type cacheItem struct {
 
 func withCache[T any](key string, cacheTtl time.Duration, fetch func() (T, string, error)) (data T, err error) {
 	// check cache first
-	if v, ok := cacheStore.Load(key); ok {
-		item := v.(*cacheItem)
-		if item.exp.After(time.Now()) {
-			return item.data.(T), nil
+	if cacheTtl > time.Second {
+		if v, ok := cacheStore.Load(key); ok {
+			item := v.(*cacheItem)
+			if item.exp.After(time.Now()) {
+				return item.data.(T), nil
+			}
 		}
 	}
 
 	unlock := cacheMutex.Lock(key)
 	defer unlock()
 
 	// check cache again after lock
-	if v, ok := cacheStore.Load(key); ok {
-		item := v.(*cacheItem)
-		if item.exp.After(time.Now()) {
-			return item.data.(T), nil
+	if cacheTtl > time.Second {
+		if v, ok := cacheStore.Load(key); ok {
+			item := v.(*cacheItem)
+			if item.exp.After(time.Now()) {
+				return item.data.(T), nil
+			}
 		}
 	}
 
@@ -51,10 +55,12 @@ func withCache[T any](key string, cacheTtl time.Duration, fetch func() (T, strin
 		return
 	}
 
-	exp := time.Now().Add(cacheTtl)
-	cacheStore.Store(key, &cacheItem{exp, data})
-	if aliasKey != "" && aliasKey != key {
-		cacheStore.Store(aliasKey, &cacheItem{exp, data})
+	if cacheTtl > time.Second {
+		exp := time.Now().Add(cacheTtl)
+		cacheStore.Store(key, &cacheItem{exp, data})
+		if aliasKey != "" && aliasKey != key {
+			cacheStore.Store(aliasKey, &cacheItem{exp, data})
+		}
 	}
 	return
 }

server/debug.go

@@ -2,7 +2,26 @@
 
 package server
 
-const (
-	DEBUG   = true
-	VERSION = "DEV"
+import (
+	"os"
+	"path"
 )
+
+// debug mode
+const DEBUG = true
+
+// always "DEV" in DEBUG mode
+const VERSION = "DEV"
+
+// mock embed.FS reads files from the current working directory in DEBUG mode
+var embedFS MockEmbedFS
+
+type MockEmbedFS struct{}
+
+func (fs MockEmbedFS) ReadFile(name string) ([]byte, error) {
+	cwd, err := os.Getwd()
+	if err != nil {
+		return nil, err
+	}
+	return os.ReadFile(path.Join(cwd, "server", name))
+}

server/release.go

@@ -2,9 +2,15 @@
 
 package server
 
-const (
-	DEBUG = false
+import (
+	"embed"
 )
 
+// production mode
+const DEBUG = false
+
 // may be changed by `-ldflags`
 var VERSION = "v136"
+
+//go:embed embed
+var embedFS embed.FS