feat: add railway preset (#253)

.changeset/short-shirts-sleep.md

@@ -0,0 +1,5 @@
+---
+"@t3-oss/env-core": minor
+---
+
+railway preset

docs/src/app/docs/customization/page.mdx

@@ -99,11 +99,10 @@ T3 Env ships the following presets out of the box, all importable from the `/pre
 - `vercel` - Vercel environment variables. See full list [here](https://vercel.com/docs/projects/environment-variables/system-environment-variables#system-environment-variables).
 - `uploadthing` - All environment variables required to use [UploadThing](https://uploadthing.com/). More info [here](https://docs.uploadthing.com/getting-started/appdir#add-env-variables).
 - `render` - Render environment variables. See full list [here](https://docs.render.com/environment-variables#all-runtimes).
+- `railway` - Railway provided system environment variables. See full list [here](https://docs.railway.app/reference/variables#railway-provided-variables).
 
 <Callout type="info">
-
-Feel free to open a PR with more presets!
-
+  Feel free to open a PR with more presets!
 </Callout>
 
 A preset is just like any other env object, so you can easily create your own:

packages/core/src/presets.ts

@@ -66,3 +66,37 @@ export const render = () =>
     },
     runtimeEnv: process.env,
   });
+
+/**
+ * Railway Environment Variables
+ * @see https://docs.railway.app/reference/variables#railway-provided-variables
+ */
+export const railway = () =>
+  createEnv({
+    server: {
+      RAILWAY_PUBLIC_DOMAIN: z.string().optional(),
+      RAILWAY_PRIVATE_DOMAIN: z.string().optional(),
+      RAILWAY_TCP_PROXY_DOMAIN: z.string().optional(),
+      RAILWAY_TCP_PROXY_PORT: z.string().optional(),
+      RAILWAY_TCP_APPLICATION_PORT: z.string().optional(),
+      RAILWAY_PROJECT_NAME: z.string().optional(),
+      RAILWAY_PROJECT_ID: z.string().optional(),
+      RAILWAY_ENVIRONMENT_NAME: z.string().optional(),
+      RAILWAY_ENVIRONMENT_ID: z.string().optional(),
+      RAILWAY_SERVICE_NAME: z.string().optional(),
+      RAILWAY_SERVICE_ID: z.string().optional(),
+      RAILWAY_REPLICA_ID: z.string().optional(),
+      RAILWAY_DEPLOYMENT_ID: z.string().optional(),
+      RAILWAY_SNAPSHOT_ID: z.string().optional(),
+      RAILWAY_VOLUME_NAME: z.string().optional(),
+      RAILWAY_VOLUME_MOUNT_PATH: z.string().optional(),
+      RAILWAY_RUN_UID: z.string().optional(),
+      RAILWAY_GIT_COMMIT_SHA: z.string().optional(),
+      RAILWAY_GIT_AUTHOR_EMAIL: z.string().optional(),
+      RAILWAY_GIT_BRANCH: z.string().optional(),
+      RAILWAY_GIT_REPO_NAME: z.string().optional(),
+      RAILWAY_GIT_REPO_OWNER: z.string().optional(),
+      RAILWAY_GIT_COMMIT_MESSAGE: z.string().optional(),
+    },
+    runtimeEnv: process.env,
+  });