add a changeset

Author: petebacondarwin

.changeset/moody-breads-pump.md

@@ -0,0 +1,19 @@
+---
+"@cloudflare/vite-plugin": minor
+"wrangler": minor
+---
+
+Add support for loading local dev vars from .env files
+
+If there are no `.dev.vars` or `.dev.vars.<environment>` files, when running Wrangler or the Vite plugin in local development mode,
+they will now try to load additional local dev vars from `.env`, `.env.local`, `.env.<environment>` and `.env.<environment>.local` files.
+
+These loaded vars are only for local development and have no effect in production to the vars in a deployed Worker.
+Wrangler and Vite will continue to load `.env` files in order to configure themselves as a tool.
+
+Further details:
+
+- In `vite build` the local vars will be computed and stored in a `.dev.vars` file next to the compiled Worker code, so that `vite preview` can use them.
+- The `wrangler types` command will similarly read the `.env` files (if no `.dev.vars` files) in order to generate the `Env` interface.
+- If the `CLOUDFLARE_INCLUDE_PROCESS_ENV` environment variable is `true` then all the environment variables found on `process.env` will be included as local dev vars.
+- Wrangler (but not Vite plugin) also now supports the `--env-file=<path/to/dotenv/file>` global CLI option. This affects both loading `.env` to configure Wrangler the tool as well as loading local dev vars.