How to configure DENO_DIR for dynamic imports?

Thanks for the Deno runtime! I came running back to Vercel because Deno Deploy doesn’t do dynamic imports and vercel-deno is a lifesaver 😸

Unfortunately, I still can’t get dynamic imports working because I get this runtime error: TypeError: Could not create TypeScript compiler cache location: "/var/task/.deno/gen/file/var/task/commands/1"

I saw that the solution was to simply set the DENO_DIR variable to something under /tmp. Unfortunately, simply setting that variable either on Vercel’s settings or with the hashbang wasn’t enough to change the directory.

This is what I have right now as my hashbang, the env var as well as the two includes for files I want to import which work fine:

#!/usr/bin/env DENO_DIR=/tmp/.deno deno run --include-files ../util/**/* --include-files ../commands/**/*

Is there any other way I can configure DENO_DIR?

[5310]

My functions are already working dynamically with v1.0

Thank you again for the fix and ofc for the runtime! 🏆

[TooTallNate]

Ok, well it’s a simple change in the bootstrap file to make it work (right now DENO_DIR is always set in that file before invoking deno. I think we can make it only set it by default, and allow to overwrite via env var).

Example: https://vercel-deno-o1u7gi9m0-tootallnate.vercel.app/api/main

You can see in the Function invocation logs that the source files are downloaded / compiled at runtime (which leads to a rather slow cold boot):

That said, I’d still like overwriting DENO_DIR be supported, so I’ll turn this into a proper PR next.