Support import with {type: json} (#1202)

Author: coderaiser

server/build.go

@@ -685,6 +685,14 @@ func (ctx *BuildContext) buildModule(analyzeMode bool) (meta *BuildMeta, include
 								}, nil
 							}
 
+							if len(args.With) > 0 && args.With["type"] == "json" {
+								return esbuild.OnResolveResult{
+									Path:        "/" + ctx.esmPath.Name() + utils.NormalizePathname(modulePath) + "?module",
+									External:    true,
+									SideEffects: esbuild.SideEffectsFalse,
+								}, nil
+							}
+
 							filename = path.Join(ctx.wd, "node_modules", ctx.esmPath.PkgName, modulePath)
 
 							// split the module that includes `export * from "external"` statement

test/issue-1197/test.ts

@@ -0,0 +1,25 @@
+import { assert, assertEquals } from "jsr:@std/assert";
+
+// related issue: https://github.com/esm-dev/esm.sh/issues/1197
+Deno.test(
+  "import with { type: 'json' }",
+  async () => {
+    const res = await fetch("http://localhost:8080/[email protected]/es2022/menu/menu.mjs");
+    const text = await res.text();
+    assert(res.ok);
+    assertEquals(res.headers.get("content-type"), "application/javascript; charset=utf-8");
+    assertEquals(res.headers.get("cache-control"), "public, max-age=31536000, immutable");
+    assert(text.includes(`import("/[email protected]/menu/importmap.json?module")`));
+  },
+);
+
+Deno.test(
+  "json?module",
+  async () => {
+    const res = await fetch("http://localhost:8080/[email protected]/menu/importmap.json?module");
+    const text = await res.text();
+    assert(res.ok);
+    assertEquals(res.headers.get("content-type"), "application/javascript; charset=utf-8");
+    assertEquals(res.headers.get("cache-control"), "public, max-age=31536000, immutable");
+  },
+);