feat: modular domain driven boilerplate

platform/config/environment.ts

@@ -0,0 +1,51 @@
+import { load } from "@std/dotenv";
+import { z, type ZodType } from "zod";
+
+import { InvalidEnvironmentKeyError } from "./errors.ts";
+import { getServiceEnvironment, type ServiceEnvironment } from "./service.ts";
+
+const env = await load();
+
+/**
+ * TODO ...
+ */
+export function getEnvironmentVariable<TType extends ZodType>({
+  key,
+  type,
+  envFallback,
+  fallback,
+}: {
+  key: string;
+  type: TType;
+  envFallback?: EnvironmentFallback;
+  fallback?: string;
+}): z.infer<TType> {
+  const serviceEnv = getServiceEnvironment();
+  const providedValue = env[key] ?? Deno.env.get(key);
+  const fallbackValue = typeof envFallback === "object" ? (envFallback[serviceEnv] ?? fallback) : fallback;
+  const toBeUsed = providedValue ?? fallbackValue;
+  try {
+    if (typeof toBeUsed === "string" && (toBeUsed.trim().startsWith("{") || toBeUsed.trim().startsWith("["))) {
+      return type.parse(JSON.parse(toBeUsed));
+    }
+    return type.parse(toBeUsed);
+  } catch (error) {
+    throw new InvalidEnvironmentKeyError(key, {
+      cause: error,
+    });
+  }
+}
+
+/*
+ |--------------------------------------------------------------------------------
+ | Types
+ |--------------------------------------------------------------------------------
+ */
+
+type EnvironmentFallback = Partial<Record<ServiceEnvironment, string>> & {
+  testing?: string;
+  local?: string;
+  stg?: string;
+  demo?: string;
+  prod?: string;
+};