fix: ReferenceError when AWS Router's viewerRequest injection uses await

[charliecode]

Fixes #6331

Problem

When using await in edge.viewerRequest.injection, accessing routerNS inside getRoutes() throws a ReferenceError: cannot access variable before initialization due to temporal dead zone (TDZ) issues in the generated CloudFront Function code.

Solution

Moved the routerNS declaration inside the getRoutes() function where it's actually used. This prevents the TDZ issue when the injected code contains await statements.

Changes

• Modified platform/src/components/aws/router.ts
• Moved const routerNS = "${kvNamespace}"; from outside getRoutes() to inside it

Testing

• Verified code compiles successfully with bun run build
• The fix matches the workaround mentioned in the issue that resolves the problem

[vimtor]

thanks for the contribution @charliecode

proof of it working

tested this against the following config:

    const api = new sst.aws.Function("MyApi", {
      handler: "api.handler",
      url: true,
    });
    const router = new sst.aws.Router("MyRouter", {
      routes: {
        "/*": api.url,
      },
      edge: {
        viewerRequest: {
          injection: `
            // Test async injection - triggers issue #6331 if not fixed
            const testAwait = await Promise.resolve("test");
          `,
        },
      },
    });

    return {
      router: router.url,
    };

before

after

[charliecode]

thanks for the contribution @charliecode

proof of it working

Glad to help 🙌