DENO_DIR remapping in deno (supporting windows)

[hayd]

At the moment you need to do:

# Compile the handler (and fetch dependencies into DENO_DIR).
DENO_DIR=.deno_dir deno fetch hello.ts

# This is the "remapping" step:
cp -R .deno_dir/gen/file/$PWD/ .deno_dir/LAMBDA_TASK_ROOT
# Note: We do the inverse of this operation in bootstrap.

zip lambda.zip -x '.deno_dir/gen/file/*' -r .deno_dir hello.ts  # other source files

I don't think this works in windows (if it does then this can be done with Deno.run).

Either

1. rewrite for Windows Deno.run (using the equivalent windows commands, specifically zip)
2. port/use a deno native zip library (e.g. JSZip, but this doesn't quite work yet).

Add this as https://deno.land/x/lambda/zip.ts (or something). Potentially support .npmignore (since this is respected by SAM it makes sense to emulate that).

[hayd]

2. will be possible in deno 0.40.0.

Edit: and should in fact be possible now with hayd/deno-zip.

[hayd]

I do not think DENO_DIR remapping works anymore at all. :(

I recommend using demo-lambda with docker so that it can be properly cached.