Initial Commit

src/services/config.ts

@@ -0,0 +1,82 @@
+import { z } from "zod";
+
+const configSchema = z.object({
+  engine: z.object({
+    mnemonic: z.string(),
+    database: z.object({
+      path: z.string().default("data/engine"),
+    }),
+  }),
+  syncServer: z.object({
+    url: z.string().default("http://localhost:3000"),
+  }),
+  database: z.object({
+    path: z.string().default("data.db"),
+  }),
+  server: z.object({
+    port: z.number().default(3000),
+    host: z.string().default("0.0.0.0"),
+    cors: z
+      .object({
+        origin: z.string().default("*"),
+        methods: z
+          .array(z.string())
+          .default(["GET", "POST", "PUT", "DELETE", "OPTIONS"]),
+        allowedHeaders: z
+          .array(z.string())
+          .default(["Content-Type", "Authorization"]),
+      })
+      .partial()
+      .prefault({}),
+  }),
+});
+
+type ConfigInput = z.input<typeof configSchema>;
+type ConfigSchema = z.output<typeof configSchema>;
+
+/**
+ * Converts an object's keys to camelCase.
+ * @param obj - The object to convert to camelCase.
+ * @returns The camelCase object.
+ */
+const toCamelCaseObject = (obj: Record<string, string>): Record<string, string> => {
+    return Object.fromEntries(Object.entries(obj).map(([key, value]) => {
+        const camelCaseKey = key.toLowerCase().replace(/([-_][a-z])/g, (group) => group.toUpperCase().replace("-", "").replace("_", ""));
+        return [camelCaseKey, value];
+    }));
+}
+
+/**
+ * The Config class is used to load and parse the configuration for the vending machine.
+ */
+export class Config {
+  static fromEnv(): Config {
+    // Parse through process.env, and convert the upperCase keys to camelCase.
+    const envConfig = toCamelCaseObject(Object(process.env));
+
+    // Parse the environment config.
+    return this.from(configSchema.parse(envConfig));
+  }
+
+  static from(config: ConfigInput): Config {
+    return new Config(configSchema.parse(config));
+  }
+
+  public get syncServer() {
+    return this.config.syncServer;
+  }
+
+  public get engine() {
+    return this.config.engine;
+  }
+
+  public get database() {
+    return this.config.database;
+  }
+
+  public get server() {
+    return this.config.server;
+  }
+
+  private constructor(private readonly config: ConfigSchema) {}
+}