Add POC / example of managing app state

apps/invoices/package.json

@@ -62,6 +62,7 @@
     "@types/react": "^18.0.27",
     "@types/react-dom": "^18.0.10",
     "@types/rimraf": "^3.0.2",
+    "@types/semver": "^7.3.13",
     "@vitejs/plugin-react": "^3.0.0",
     "@vitest/coverage-c8": "^0.28.4",
     "dotenv": "^16.0.3",
@@ -70,7 +71,6 @@
     "rimraf": "^3.0.2",
     "typescript": "4.9.5",
     "vite": "^4.2.1",
-    "vitest": "^0.30.1",
-    "@types/semver": "^7.3.13"
+    "vitest": "^0.30.1"
   }
 }

apps/invoices/src/modules/app-configuration/config-v3.test.ts

@@ -0,0 +1,93 @@
+import { describe, test, expect } from "vitest";
+import { ConfigModel } from "./config-v3";
+
+describe("configv3", () => {
+  test("Constructs", () => {
+    const instance = new ConfigModel();
+
+    expect(instance).toBeDefined();
+  });
+
+  test("Serializes", () => {
+    const instance = new ConfigModel({
+      overrides: {
+        usd: {
+          channel: {
+            slug: "usd",
+          },
+          address: {
+            city: "Krakow",
+            cityArea: "krowodrza",
+            country: "poland",
+            streetAddress1: "Some street",
+            streetAddress2: "",
+            postalCode: "12345",
+            companyName: "Saleor",
+            countryArea: "Malopolskie",
+          },
+        },
+      },
+    });
+
+    expect(instance.serialize()).toEqual(
+      '{"overrides":{"usd":{"channel":{"slug":"usd"},"address":{"city":"Krakow","cityArea":"krowodrza","country":"poland","streetAddress1":"Some street","streetAddress2":"","postalCode":"12345","companyName":"Saleor","countryArea":"Malopolskie"}}}}'
+    );
+  });
+
+  test("Parses root schema", () => {
+    const instance = ConfigModel.parse(
+      '{"overrides":{"usd":{"channel":{"slug":"usd"},"address":{"city":"Krakow","cityArea":"krowodrza","country":"poland","streetAddress1":"Some street","streetAddress2":"","postalCode":"12345","companyName":"Saleor","countryArea":"Malopolskie"}}}}'
+    );
+
+    expect(instance.getOverridesArray()).toHaveLength(1);
+    expect(instance.getOverridesArray()[0].channel.slug).toEqual("usd");
+  });
+
+  test("Appends override", () => {
+    const instance = new ConfigModel();
+
+    expect(instance.getOverridesArray()).toHaveLength(0);
+
+    instance.addOverride("usd_USD", {
+      city: "Krakow",
+      cityArea: "krowodrza",
+      country: "poland",
+      streetAddress1: "Some street",
+      streetAddress2: "",
+      postalCode: "12345",
+      companyName: "Saleor",
+      countryArea: "Malopolskie",
+    });
+
+    expect(instance.getOverridesArray()).toHaveLength(1);
+    expect(instance.getOverridesArray()[0].channel.slug).toEqual("usd_USD");
+  });
+
+  test("Removes override", () => {
+    const instance = new ConfigModel({
+      overrides: {
+        usd: {
+          channel: {
+            slug: "usd",
+          },
+          address: {
+            city: "Krakow",
+            cityArea: "krowodrza",
+            country: "poland",
+            streetAddress1: "Some street",
+            streetAddress2: "",
+            postalCode: "12345",
+            companyName: "Saleor",
+            countryArea: "Malopolskie",
+          },
+        },
+      },
+    });
+
+    instance.removeOverride("usd");
+
+    expect(instance.getOverridesArray()).toHaveLength(0);
+
+    expect(instance.serialize()).toEqual(`{"overrides":{}}`);
+  });
+});

apps/invoices/src/modules/app-configuration/config-v3.ts

@@ -0,0 +1,137 @@
+import { z } from "zod";
+import { test } from "vitest";
+import { EncryptedMetadataManager, SettingsManager } from "@saleor/app-sdk/settings-manager";
+
+const AddressSchema = z.object({
+  companyName: z.string(),
+  cityArea: z.string(),
+  countryArea: z.string(),
+  streetAddress1: z.string(),
+  streetAddress2: z.string(),
+  postalCode: z.string(),
+  city: z.string(),
+  country: z.string(),
+});
+
+const ChannelSchema = z.object({
+  slug: z.string().min(1),
+});
+
+const AddressOverrideSchema = z.object({
+  address: AddressSchema,
+  channel: ChannelSchema,
+});
+
+const RootConfigSchema = z.object({
+  overrides: z.record(AddressOverrideSchema),
+});
+
+/**
+ * Root model that can serialize to json and parse from json.
+ *
+ * Uses Zod to parse and validate
+ *
+ * Adds domain methods on top
+ */
+export class ConfigModel {
+  /**
+   * Stores its own data as deep, single json, structured and validated by zod
+   */
+  private rootData: z.infer<typeof RootConfigSchema> = { overrides: {} };
+
+  constructor(initialConfig?: z.infer<typeof RootConfigSchema>) {
+    /**
+     * Sets its own initial state but also allows to inject - then validate
+     */
+    if (initialConfig) {
+      this.rootData = RootConfigSchema.parse(initialConfig);
+    }
+  }
+
+  /**
+   * Can statically parse itself, ensures parse/serialize work together
+   */
+  static parse(serialized: string) {
+    return new ConfigModel(RootConfigSchema.parse(JSON.parse(serialized)));
+  }
+
+  /**
+   * Serializes to json, even if some extra methods are saved (can be replaced/cleaned up if needed),
+   * zod will remove unknown members after parsing
+   */
+  serialize() {
+    return JSON.stringify(this.rootData);
+  }
+
+  /**
+   * Domain methods needed by app
+   */
+  getOverridesArray() {
+    return Object.values(this.rootData.overrides);
+  }
+
+  /**
+   * Domain methods needed by app
+   */
+  isChannelOverridden(slug: string) {
+    return Boolean(this.rootData.overrides[slug]);
+  }
+
+  /**
+   * Domain methods needed by app
+   */
+  addOverride(slug: string, address: z.infer<typeof AddressSchema>) {
+    /**
+     * Perform additional checks, for example implement "update" method and forbid to implicit override
+     */
+    if (this.rootData.overrides[slug]) {
+      throw new Error("Channel override already exists");
+    }
+
+    /**
+     * Ensure input is correct. Use "satisfied" because zod accepts "unknown"
+     */
+    this.rootData.overrides[slug] = AddressOverrideSchema.parse({
+      channel: {
+        slug: slug,
+      },
+      address: address,
+    } satisfies z.infer<typeof AddressOverrideSchema>);
+
+    /**
+     * Return this to allow chaining, optional
+     */
+    return this;
+  }
+
+  /**
+   * Domain methods needed by app
+   */
+  removeOverride(slug: string) {
+    delete this.rootData.overrides[slug];
+
+    return this;
+  }
+}
+
+/**
+ * model can be connected with MetadataManager to automatically fetch and parse data.
+ *
+ * So for app usage this can be the only "root source" used
+ */
+abstract class ConfigManager {
+  /**
+   * Uses metadata manager to read/write
+   */
+  abstract metadataManager: SettingsManager;
+
+  /**
+   * Can fetch config and parse it to domain model
+   */
+  abstract loadConfig(): Promise<ConfigModel>;
+
+  /**
+   * Can serialize and  save config in metadata
+   */
+  abstract saveConfig(config: ConfigModel): Promise<void>;
+}

apps/invoices/tsconfig.json

@@ -13,7 +13,8 @@
     "resolveJsonModule": true,
     "isolatedModules": true,
     "jsx": "preserve",
-    "incremental": true
+    "incremental": true,
+    "experimentalDecorators": true
   },
   "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx"],
   "exclude": ["node_modules"]