Merge pull request 'Feature: Basic Events, Models and Projections' (#2) from feat-base-projections into main

Reviewed-on: #2

package.json

@@ -9,24 +9,24 @@
     "apps/**/*"
   ],
   "devDependencies": {
-    "@eslint/js": "^9.10.0",
+    "@eslint/js": "^9.12.0",
     "@types/eslint": "^9.6.1",
     "@types/eslint__js": "^8.42.3",
     "cross-env": "^7.0.3",
-    "eslint": "^9.10.0",
+    "eslint": "^9.12.0",
     "husky": "^9.1.6",
     "lint-staged": "^15.2.10",
     "prettier": "^3.3.3",
     "tsx": "^4.19.1",
-    "typescript": "^5.6.2",
-    "typescript-eslint": "^8.6.0",
-    "zx": "^8.1.7"
+    "typescript": "^5.6.3",
+    "typescript-eslint": "^8.8.1",
+    "zx": "^8.1.9"
   },
   "scripts": {
     "lint": "eslint . --fix --report-unused-disable-directives",
     "format": "prettier --write .",
     "test": "yarn workspaces foreach -vvpA run test --run --clearScreen false",
-    "build": "yarn workspaces foreach -vvpA --topological-dev run build",
+    "build": "yarn workspaces foreach -vvpA --topological run build",
     "add-package": "tsx ./scripts/add-package.ts",
     "postinstall": "husky"
   }

packages/fabric/core/README.md

@@ -1 +1 @@
-# @ulthar/fabric-core
+# @fabric/core

packages/fabric/core/package.json

@@ -1,31 +1,25 @@
 {
-  "name": "@ulthar/fabric-core",
+  "name": "@fabric/core",
+  "private": true,
+  "sideEffects": false,
   "type": "module",
-  "module": "dist/index.js",
-  "main": "dist/index.js",
-  "types": "dist/index.d.ts",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
   "exports": {
-    ".": "./dist/index.js",
-    "./domain": "./dist/domain.js",
-    "./validation": "./dist/validation.js",
-    "./validation/fields": "./dist/validation/fields/index.js"
+    ".": "./dist/index.js"
   },
   "files": [
     "dist"
   ],
-  "private": true,
   "packageManager": "yarn@4.1.1",
   "devDependencies": {
-    "@types/validator": "^13.12.2",
-    "typescript": "^5.6.2",
-    "vitest": "^2.1.1"
+    "@vitest/coverage-v8": "^2.1.2",
+    "typescript": "^5.6.3",
+    "vitest": "^2.1.2"
   },
   "scripts": {
     "test": "vitest",
+    "coverage": "vitest run --coverage",
     "build": "tsc -p tsconfig.build.json"
-  },
-  "sideEffects": false,
-  "dependencies": {
-    "validator": "^13.12.0"
   }
 }

packages/fabric/core/src/domain/entity/files/domain-file.ts

@@ -1,9 +0,0 @@
-import { BaseFile } from "../../../files/base-file.js";
-import { Entity } from "../entity.js";
-
-/**
- * Represents a file as managed by the domain.
- */
-export interface DomainFile extends BaseFile, Entity {
-  url: string;
-}

packages/fabric/core/src/domain/entity/files/image-file.ts

@@ -1,9 +0,0 @@
-import { ImageMimeType } from "../../../files/mime-type.js";
-import { DomainFile } from "./domain-file.js";
-
-/**
- * Represents an image file.
- */
-export interface ImageFile extends DomainFile {
-  mimeType: ImageMimeType;
-}

packages/fabric/core/src/domain/entity/files/index.ts

@@ -1,2 +0,0 @@
-export * from "./domain-file.js";
-export * from "./image-file.js";

packages/fabric/core/src/domain/entity/index.ts

@@ -1 +0,0 @@
-export * from "./entity.js";

packages/fabric/core/src/domain/events/event.ts

@@ -1,12 +0,0 @@
-/* eslint-disable @typescript-eslint/no-explicit-any */
-import { TaggedVariant } from "../../variant/variant.js";
-import { UUID } from "../types/uuid.js";
-
-/**
- * An event is a tagged variant with a payload and a timestamp.
- */
-export interface Event<TTag extends string = string, TPayload = any>
-  extends TaggedVariant<TTag> {
-  streamId: UUID;
-  payload: TPayload;
-}

packages/fabric/core/src/domain/index.ts

@@ -1,5 +0,0 @@
-export * from "./entity/index.js";
-export * from "./models/index.js";
-export * from "./security/index.js";
-export * from "./types/index.js";
-export * from "./use-case/index.js";

packages/fabric/core/src/domain/models/create-model.ts

@@ -1,32 +0,0 @@
-import { FieldDefinition } from "./fields/index.js";
-
-export interface ModelDefinition<
-  TName extends string = string,
-  TFields extends Record<string, FieldDefinition> = Record<
-    string,
-    FieldDefinition
-  >,
-> {
-  name: TName;
-  fields: TFields;
-}
-
-export type ModelName<
-  TModel extends ModelDefinition<string, Record<string, FieldDefinition>>,
-> = TModel["name"];
-
-export type ModelFromName<
-  TModels extends ModelDefinition<string, Record<string, FieldDefinition>>,
-  TName extends ModelName<TModels>,
-> = Extract<TModels, { name: TName }>;
-
-export type ModelFieldNames<
-  TModel extends ModelDefinition<string, Record<string, FieldDefinition>>,
-> = keyof TModel["fields"];
-
-export function createModel<
-  TName extends string,
-  TFields extends Record<string, FieldDefinition>,
->(opts: ModelDefinition<TName, TFields>): ModelDefinition<TName, TFields> {
-  return opts;
-}

packages/fabric/core/src/domain/models/fields/field-to-type.ts

@@ -1,9 +0,0 @@
-import { UUID } from "../../types/uuid.js";
-import { StringField } from "./string-field.js";
-import { UUIDField } from "./uuid-field.js";
-
-export type FieldToType<TField> = TField extends StringField
-  ? string
-  : TField extends UUIDField
-    ? UUID
-    : never;

packages/fabric/core/src/domain/models/fields/index.ts

@@ -1,10 +0,0 @@
-import { createStringField, StringField } from "./string-field.js";
-import { createUUIDField, UUIDField } from "./uuid-field.js";
-export * from "./base-field.js";
-
-export type FieldDefinition = StringField | UUIDField;
-
-export namespace Field {
-  export const string = createStringField;
-  export const uuid = createUUIDField;
-}

packages/fabric/core/src/domain/models/fields/uuid-field.ts

@@ -1,15 +0,0 @@
-import { TaggedVariant, VariantTag } from "../../../variant/variant.js";
-import { BaseField } from "./base-field.js";
-
-export interface UUIDOptions extends BaseField {
-  isPrimaryKey?: boolean;
-}
-
-export interface UUIDField extends TaggedVariant<"UUIDField">, UUIDOptions {}
-
-export function createUUIDField(opts: UUIDOptions): UUIDField {
-  return {
-    [VariantTag]: "UUIDField",
-    ...opts,
-  };
-}

packages/fabric/core/src/domain/models/index.ts

@@ -1,4 +0,0 @@
-export * from "./create-model.js";
-export * from "./fields/index.js";
-export * from "./model-to-type.js";
-export * from "./relations/index.js";

packages/fabric/core/src/domain/models/model-to-type.ts

@@ -1,6 +0,0 @@
-import { ModelDefinition } from "./create-model.js";
-import { FieldToType } from "./fields/field-to-type.js";
-
-export type ModelToType<TModel extends ModelDefinition> = {
-  [K in keyof TModel["fields"]]: FieldToType<TModel["fields"][K]>;
-};

packages/fabric/core/src/domain/models/relations/index.ts

@@ -1,5 +0,0 @@
-import { OneToOneRelation } from "./one-to-one.js";
-
-export type RelationDefinition = OneToOneRelation<string, string>;
-
-export namespace Relations {}

packages/fabric/core/src/domain/models/relations/one-to-many.ts

@@ -1,34 +0,0 @@
-import { TaggedVariant, VariantTag } from "../../../variant/variant.js";
-
-export interface OneToManyRelationOptions<
-  TOwner extends string,
-  TTarget extends string,
-> {
-  /**
-   * The owner of the relation. In this case is the "one" side of the relation.
-   */
-  owner: TOwner;
-
-  /**
-   * The target of the relation. In this case is the "many" side of the relation.
-   */
-  target: TTarget;
-}
-
-export interface OneToManyRelation<
-  TOwner extends string,
-  TTarget extends string,
-> extends TaggedVariant<"ONE_TO_MANY_RELATION">,
-    OneToManyRelationOptions<TOwner, TTarget> {}
-
-export function createOneToManyRelation<
-  TOwner extends string,
-  TTarget extends string,
->(
-  opts: OneToManyRelationOptions<TOwner, TTarget>,
-): OneToManyRelation<TOwner, TTarget> {
-  return {
-    [VariantTag]: "ONE_TO_MANY_RELATION",
-    ...opts,
-  };
-}

packages/fabric/core/src/domain/models/relations/one-to-one.ts

@@ -1,33 +0,0 @@
-import { TaggedVariant, VariantTag } from "../../../variant/variant.js";
-
-export interface OneToOneRelationOptions<
-  TOwner extends string,
-  TTarget extends string,
-> {
-  /**
-   * The owner of the relation.
-   */
-  owner: TOwner;
-
-  /**
-   * The target of the relation
-   *
-   */
-  target: TTarget;
-}
-
-export interface OneToOneRelation<TOwner extends string, TTarget extends string>
-  extends TaggedVariant<"ONE_TO_ONE_RELATION">,
-    OneToOneRelationOptions<TOwner, TTarget> {}
-
-export function createOneToOneRelation<
-  TOwner extends string,
-  TTarget extends string,
->(
-  opts: OneToOneRelationOptions<TOwner, TTarget>,
-): OneToOneRelation<TOwner, TTarget> {
-  return {
-    [VariantTag]: "ONE_TO_ONE_RELATION",
-    ...opts,
-  };
-}

packages/fabric/core/src/domain/types/index.ts

@@ -1,3 +0,0 @@
-export * from "./email.js";
-export * from "./semver.js";
-export * from "./uuid.js";

packages/fabric/core/src/error/tagged-error.ts

@@ -3,14 +3,15 @@ import { TaggedVariant, VariantTag } from "../variant/index.js";
 /**
  * A TaggedError is a tagged variant with an error message.
  */
-export class TaggedError<Tag extends string>
+export abstract class TaggedError<Tag extends string = string>
   extends Error
   implements TaggedVariant<Tag>
 {
   readonly [VariantTag]: Tag;
 
-  constructor(tag: Tag) {
-    super();
+  constructor(tag: Tag, message?: string) {
+    super(message);
     this[VariantTag] = tag;
+    this.name = tag;
   }
 }

packages/fabric/core/src/error/unexpected-error.ts

@@ -8,12 +8,7 @@ import { TaggedError } from "./tagged-error.js";
  * we must be prepared to handle.
  */
 export class UnexpectedError extends TaggedError<"UnexpectedError"> {
-  constructor(readonly context: Record<string, unknown> = {}) {
-    super("UnexpectedError");
-    this.message = "An unexpected error occurred";
-  }
-
-  toString() {
-    return `UnexpectedError: ${this.message}\n${JSON.stringify(this.context, null, 2)}`;
+  constructor(message?: string) {
+    super("UnexpectedError", message);
   }
 }

packages/fabric/core/src/index.ts

@@ -1,9 +1,9 @@
 export * from "./array/index.js";
-export * from "./domain/index.js";
 export * from "./error/index.js";
 export * from "./record/index.js";
 export * from "./result/index.js";
-export * from "./storage/index.js";
+export * from "./run/index.js";
 export * from "./time/index.js";
 export * from "./types/index.js";
+export * from "./utils/index.js";
 export * from "./variant/index.js";

packages/fabric/core/src/result/async-result.ts

@@ -1,11 +1,33 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
 import { TaggedError } from "../error/tagged-error.js";
+import { UnexpectedError } from "../error/unexpected-error.js";
+import { MaybePromise } from "../types/maybe-promise.js";
 import { Result } from "./result.js";
 
 /**
- * Un AsyncResult representa el resultado de una operación asíncrona que puede
- * resolver en un valor de tipo `TValue` o en un error de tipo `TError`.
+ * An AsyncResult represents the result of an asynchronous operation that can
+ * resolve to a value of type `TValue` or an error of type `TError`.
  */
 export type AsyncResult<
-  TValue,
-  TError extends TaggedError<string> = never,
+  TValue = any,
+  TError extends TaggedError = never,
 > = Promise<Result<TValue, TError>>;
+
+export namespace AsyncResult {
+  export async function tryFrom<T, TError extends TaggedError>(
+    fn: () => MaybePromise<T>,
+    errorMapper: (error: any) => TError,
+  ): AsyncResult<T, TError> {
+    try {
+      return Result.succeedWith(await fn());
+    } catch (error) {
+      return Result.failWith(errorMapper(error));
+    }
+  }
+
+  export async function from<T>(
+    fn: () => MaybePromise<T>,
+  ): AsyncResult<T, never> {
+    return tryFrom(fn, (error) => new UnexpectedError(error) as never);
+  }
+}

packages/fabric/core/src/result/result.spec.ts

@@ -0,0 +1,57 @@
+import { describe, expect, expectTypeOf, it, vitest } from "vitest";
+import { UnexpectedError } from "../error/unexpected-error.js";
+import { Result } from "./result.js";
+
+describe("Result", () => {
+  describe("isOk", () => {
+    it("should return true if the result is ok", () => {
+      const result = Result.succeedWith(1) as Result<number, UnexpectedError>;
+
+      expect(result.isOk()).toBe(true);
+
+      if (result.isOk()) {
+        expect(result.value).toEqual(1);
+
+        expectTypeOf(result).toEqualTypeOf<Result<number, never>>();
+      }
+    });
+  });
+
+  describe("isError", () => {
+    it("should return true if the result is an error", () => {
+      const result = Result.failWith(new UnexpectedError()) as Result<
+        number,
+        UnexpectedError
+      >;
+
+      expect(result.isError()).toBe(true);
+
+      if (result.isError()) {
+        expect(result.value).toBeInstanceOf(UnexpectedError);
+
+        expectTypeOf(result).toEqualTypeOf<Result<never, UnexpectedError>>();
+      }
+    });
+  });
+
+  describe("Map", () => {
+    it("should return the result of the last function", () => {
+      const x = 0;
+
+      const result = Result.succeedWith(x + 1).map((x) => x * 2);
+
+      expect(result.unwrapOrThrow()).toEqual(2);
+
+      expectTypeOf(result).toEqualTypeOf<Result<number, never>>();
+    });
+
+    it("should not execute the function if the result is an error", () => {
+      const fn = vitest.fn();
+      const result = Result.failWith(new UnexpectedError()).map(fn);
+
+      expect(result.isError()).toBe(true);
+
+      expect(fn).not.toHaveBeenCalled();
+    });
+  });
+});

packages/fabric/core/src/result/result.ts

@@ -1,9 +1,151 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+import { isError } from "../error/is-error.js";
 import { TaggedError } from "../error/tagged-error.js";
 
 /**
- * Un Result representa el resultado de una operación
- * que puede ser un valor de tipo `TValue` o un error `TError`.
+ * A Result represents the outcome of an operation
+ * that can be either a value of type `TValue` or an error `TError`.
  */
-export type Result<TValue, TError extends TaggedError<string>> =
-  | TValue
-  | TError;
+export class Result<TValue, TError extends TaggedError = never> {
+  static succeedWith<T>(value: T): Result<T, never> {
+    return new Result<T, never>(value);
+  }
+
+  static failWith<T extends TaggedError>(error: T): Result<never, T> {
+    return new Result<never, T>(error);
+  }
+
+  static ok(): Result<void, never>;
+  static ok<T>(value: T): Result<T, never>;
+  static ok(value?: any) {
+    return new Result(value ?? undefined);
+  }
+
+  static tryFrom<T, TError extends TaggedError>(
+    fn: () => T,
+    errorMapper: (error: any) => TError,
+  ): Result<T, TError> {
+    try {
+      return Result.succeedWith(fn());
+    } catch (error) {
+      return Result.failWith(errorMapper(error));
+    }
+  }
+
+  private constructor(readonly value: TValue | TError) {}
+
+  /**
+   * Unwrap the value of the result.
+   * If the result is an error, it will throw the error.
+   */
+  unwrapOrThrow(): TValue {
+    if (isError(this.value)) {
+      throw this.value;
+    }
+
+    return this.value as TValue;
+  }
+
+  /**
+   * Throw the error if the result is an error.
+   * otherwise, do nothing.
+   */
+  orThrow(): void {
+    if (isError(this.value)) {
+      throw this.value;
+    }
+  }
+
+  unwrapErrorOrThrow(): TError {
+    if (!isError(this.value)) {
+      throw new Error("Result is not an error");
+    }
+
+    return this.value;
+  }
+
+  /**
+   * Check if the result is a success.
+   */
+  isOk(): this is Result<TValue, never> {
+    return !isError(this.value);
+  }
+
+  /**
+   * Check if the result is an error.
+   */
+  isError(): this is Result<never, TError> {
+    return isError(this.value);
+  }
+
+  /**
+   * Map a function over the value of the result.
+   */
+  map<TMappedValue>(
+    fn: (value: TValue) => TMappedValue,
+  ): Result<TMappedValue, TError> {
+    if (!isError(this.value)) {
+      return Result.succeedWith(fn(this.value as TValue));
+    }
+
+    return this as any;
+  }
+
+  /**
+   * Maps a function over the value of the result and flattens the result.
+   */
+  flatMap<TMappedValue, TMappedError extends TaggedError>(
+    fn: (value: TValue) => Result<TMappedValue, TMappedError>,
+  ): Result<TMappedValue, TError | TMappedError> {
+    if (!isError(this.value)) {
+      return fn(this.value as TValue) as any;
+    }
+
+    return this as any;
+  }
+
+  /**
+   * Try to map a function over the value of the result.
+   * If the function throws an error, the result will be a failure.
+   */
+  tryMap<TMappedValue>(
+    fn: (value: TValue) => TMappedValue,
+    errMapper: (error: any) => TError,
+  ): Result<TMappedValue, TError> {
+    if (!isError(this.value)) {
+      try {
+        return Result.succeedWith(fn(this.value as TValue));
+      } catch (error) {
+        return Result.failWith(errMapper(error));
+      }
+    }
+
+    return this as any;
+  }
+
+  /**
+   * Map a function over the error of the result.
+   */
+  mapError<TMappedError extends TaggedError>(
+    fn: (error: TError) => TMappedError,
+  ): Result<TValue, TMappedError> {
+    if (isError(this.value)) {
+      return Result.failWith(fn(this.value as TError));
+    }
+
+    return this as unknown as Result<TValue, TMappedError>;
+  }
+
+  /**
+   * Taps a function if the result is a success.
+   * This is useful for side effects that do not modify the result.
+   */
+  tap(fn: (value: TValue) => void): Result<TValue, TError> {
+    if (!isError(this.value)) {
+      fn(this.value as TValue);
+    }
+
+    return this;
+  }
+}

packages/fabric/core/src/run/index.ts

@@ -0,0 +1 @@
+export * from "./run.js";

packages/fabric/core/src/run/run.spec.ts

@@ -0,0 +1,28 @@
+import { describe, expect, it } from "vitest";
+import { UnexpectedError } from "../error/unexpected-error.js";
+import { Result } from "../result/result.js";
+import { Run } from "./run.js";
+
+describe("Run", () => {
+  describe("In Sequence", () => {
+    it("should pipe the results of multiple async functions", async () => {
+      const result = await Run.seq(
+        async () => Result.succeedWith(1),
+        async (x) => Result.succeedWith(x + 1),
+        async (x) => Result.succeedWith(x * 2),
+      );
+
+      expect(result.unwrapOrThrow()).toEqual(4);
+    });
+
+    it("should return the first error if one of the functions fails", async () => {
+      const result = await Run.seq(
+        async () => Result.succeedWith(1),
+        async () => Result.failWith(new UnexpectedError()),
+        async (x) => Result.succeedWith(x * 2),
+      );
+
+      expect(result.isError()).toBe(true);
+    });
+  });
+});

packages/fabric/core/src/run/run.ts

@@ -0,0 +1,87 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+import { TaggedError } from "../error/tagged-error.js";
+import { AsyncResult } from "../result/async-result.js";
+
+export namespace Run {
+  // prettier-ignore
+  export async function seq<
+    T1, TE1 extends TaggedError,
+    T2, TE2 extends TaggedError,
+  >(
+    fn1: () => AsyncResult<T1, TE1>,
+    fn2: (value: T1) => AsyncResult<T2, TE2>,
+  ): AsyncResult<T2, TE1 | TE2>;
+  // prettier-ignore
+  export async function seq<
+    T1, TE1 extends TaggedError,
+    T2, TE2 extends TaggedError,
+    T3, TE3 extends TaggedError,
+  >(
+    fn1: () => AsyncResult<T1, TE1>,
+    fn2: (value: T1) => AsyncResult<T2, TE2>,
+    fn3: (value: T2) => AsyncResult<T3, TE3>,
+  ): AsyncResult<T3, TE1 | TE2 | TE3>;
+  // prettier-ignore
+  export async function seq<
+    T1, TE1 extends TaggedError,
+    T2, TE2 extends TaggedError,
+    T3, TE3 extends TaggedError,
+    T4, TE4 extends TaggedError,
+  >(
+    fn1: () => AsyncResult<T1, TE1>,
+    fn2: (value: T1) => AsyncResult<T2, TE2>,
+    fn3: (value: T2) => AsyncResult<T3, TE3>,
+    fn4: (value: T3) => AsyncResult<T4, TE4>,
+  ): AsyncResult<T4, TE1 | TE2 | TE3 | TE4>;
+  export async function seq(
+    ...fns: ((...args: any[]) => AsyncResult<any, any>)[]
+  ): AsyncResult<any, any> {
+    let result = await fns[0]();
+
+    for (let i = 1; i < fns.length; i++) {
+      if (result.isError()) {
+        return result;
+      }
+
+      result = await fns[i](result.unwrapOrThrow());
+    }
+
+    return result;
+  }
+
+  // prettier-ignore
+  export async function seqUNSAFE<
+    T1, TE1 extends TaggedError,
+    T2, TE2 extends TaggedError,
+  >(
+    fn1: () => AsyncResult<T1, TE1>,
+    fn2: (value: T1) => AsyncResult<T2, TE2>,
+  ): Promise<T2>;
+  // prettier-ignore
+  export async function seqUNSAFE<
+    T1,TE1 extends TaggedError,
+    T2,TE2 extends TaggedError,
+    T3,TE3 extends TaggedError,
+  >(
+    fn1: () => AsyncResult<T1, TE1>,
+    fn2: (value: T1) => AsyncResult<T2, TE2>,
+    fn3: (value: T2) => AsyncResult<T3, TE3>,
+  ): Promise<T2>;
+  export async function seqUNSAFE(
+    ...fns: ((...args: any[]) => AsyncResult<any, any>)[]
+  ): Promise<any> {
+    const result = await (seq as any)(...fns);
+
+    if (result.isError()) {
+      throw result.unwrapOrThrow();
+    }
+
+    return result.unwrapOrThrow();
+  }
+
+  export async function UNSAFE<T, TError extends TaggedError>(
+    fn: () => AsyncResult<T, TError>,
+  ): Promise<T> {
+    return (await fn()).unwrapOrThrow();
+  }
+}

packages/fabric/core/src/storage/errors/query-error.ts

@@ -1,11 +0,0 @@
-/* eslint-disable @typescript-eslint/no-explicit-any */
-import { TaggedError } from "../../error/tagged-error.js";
-
-export class StoreQueryError extends TaggedError<"StoreQueryError"> {
-  constructor(
-    public message: string,
-    public context: any,
-  ) {
-    super("StoreQueryError");
-  }
-}

packages/fabric/core/src/storage/event-store.ts

@@ -1,43 +0,0 @@
-import { Event } from "../domain/events/event.js";
-import { UUID } from "../domain/index.js";
-import { AsyncResult } from "../result/async-result.js";
-import { PosixDate } from "../time/posix-date.js";
-import { MaybePromise } from "../types/maybe-promise.js";
-import { StoreQueryError } from "./errors/query-error.js";
-
-export interface EventStore<TEvent extends Event = Event> {
-  getStream<TEventStreamEvent extends TEvent>(
-    streamId: UUID,
-  ): AsyncResult<EventStream<TEventStreamEvent>, StoreQueryError>;
-
-  appendToStream<TEvent extends Event>(
-    streamId: UUID,
-    events: TEvent,
-  ): AsyncResult<void, StoreQueryError>;
-}
-
-export interface EventStream<TEvent extends Event = Event> {
-  getCurrentVersion(): bigint;
-
-  append(events: TEvent): AsyncResult<StoredEvent<TEvent>, StoreQueryError>;
-
-  subscribe(callback: (event: StoredEvent<TEvent>) => MaybePromise<void>): void;
-
-  getEvents(
-    opts?: EventFilterOptions,
-  ): AsyncResult<StoredEvent<TEvent>[], StoreQueryError>;
-}
-
-export interface EventFilterOptions {
-  fromDate?: PosixDate;
-  toDate?: PosixDate;
-  fromVersion?: number;
-  toVersion?: number;
-  limit?: number;
-  offset?: number;
-}
-
-export type StoredEvent<TEvent extends Event = Event> = TEvent & {
-  version: bigint;
-  timestamp: number;
-};

packages/fabric/core/src/storage/index.ts

@@ -1,5 +0,0 @@
-export * from "./errors/index.js";
-export * from "./event-store.js";
-export * from "./query/index.js";
-export * from "./state-store.js";
-export * from "./storage-driver.js";

packages/fabric/core/src/storage/query/query-builder.ts

@@ -1,75 +0,0 @@
-import {
-  ModelDefinition,
-  ModelFromName,
-  ModelName,
-} from "../../domain/models/create-model.js";
-import { ModelToType } from "../../domain/models/model-to-type.js";
-import { AsyncResult } from "../../result/async-result.js";
-import { Keyof } from "../../types/index.js";
-import { StoreQueryError } from "../errors/query-error.js";
-import { StorageDriver } from "../storage-driver.js";
-import { FilterOptions } from "./filter-options.js";
-import { OrderByOptions } from "./order-by-options.js";
-import {
-  QueryDefinition,
-  SelectableQuery,
-  StoreLimitableQuery,
-  StoreQuery,
-  StoreSortableQuery,
-} from "./query.js";
-
-export class QueryBuilder<
-  TModels extends ModelDefinition,
-  TEntityName extends ModelName<TModels>,
-  T = ModelToType<ModelFromName<TModels, TEntityName>>,
-> implements StoreQuery<T>
-{
-  constructor(
-    private driver: StorageDriver,
-    private query: QueryDefinition<TEntityName>,
-  ) {}
-
-  where(where: FilterOptions<T>): StoreSortableQuery<T> {
-    this.query = {
-      ...this.query,
-      where,
-    };
-    return this;
-  }
-
-  orderBy(opts: OrderByOptions<T>): StoreLimitableQuery<T> {
-    this.query = {
-      ...this.query,
-      orderBy: opts,
-    };
-    return this;
-  }
-
-  limit(limit: number, offset?: number | undefined): SelectableQuery<T> {
-    this.query = {
-      ...this.query,
-      limit,
-      offset,
-    };
-
-    return this;
-  }
-
-  select<K extends Keyof<T>>(
-    keys?: K[],
-  ): AsyncResult<Pick<T, K>[], StoreQueryError> {
-    return this.driver.select({
-      ...this.query,
-      keys,
-    });
-  }
-
-  selectOne<K extends Keyof<T>>(
-    keys?: K[],
-  ): AsyncResult<Pick<T, K>, StoreQueryError> {
-    return this.driver.selectOne({
-      ...this.query,
-      keys,
-    });
-  }
-}

packages/fabric/core/src/storage/state-store.ts

@@ -1,16 +0,0 @@
-/* eslint-disable @typescript-eslint/no-explicit-any */
-import {
-  ModelDefinition,
-  ModelFromName,
-  ModelName,
-} from "../domain/models/create-model.js";
-import { ModelToType } from "../domain/models/model-to-type.js";
-import { StoreQuery } from "./query/query.js";
-
-export interface StateStore<
-  TModels extends ModelDefinition<string, Record<string, any>>,
-> {
-  from<TEntityName extends ModelName<TModels>>(
-    entityName: TEntityName,
-  ): StoreQuery<ModelToType<ModelFromName<TModels, TEntityName>>>;
-}

packages/fabric/core/src/storage/storage-driver.ts

@@ -1,62 +0,0 @@
-/* eslint-disable @typescript-eslint/no-explicit-any */
-
-import { ModelDefinition } from "../domain/models/create-model.js";
-import { UnexpectedError } from "../error/unexpected-error.js";
-import { AsyncResult } from "../result/async-result.js";
-import { CircularDependencyError } from "./errors/circular-dependency-error.js";
-import { StoreQueryError } from "./errors/query-error.js";
-import { QueryDefinition } from "./query/query.js";
-
-export interface StorageDriver {
-  /**
-   * Insert data into the store
-   */
-  insert(
-    collectionName: string,
-    record: Record<string, any>,
-  ): AsyncResult<void, StoreQueryError>;
-
-  /**
-   * Run a select query against the store.
-   */
-  select(query: QueryDefinition): AsyncResult<any[], StoreQueryError>;
-
-  /**
-   * Run a select query against the store.
-   */
-  selectOne(query: QueryDefinition): AsyncResult<any, StoreQueryError>;
-
-  /**
-   * Sincronice the store with the schema.
-   */
-  sync(
-    schema: ModelDefinition[],
-  ): AsyncResult<void, StoreQueryError | CircularDependencyError>;
-
-  /**
-   * Drop the store. This is a destructive operation.
-   */
-  drop(): AsyncResult<void, StoreQueryError>;
-
-  /**
-   * Close the store.
-   */
-  close(): AsyncResult<void, UnexpectedError>;
-
-  /**
-   * Update a record in the store.
-   */
-  update(
-    collectionName: string,
-    id: string,
-    record: Record<string, any>,
-  ): AsyncResult<void, StoreQueryError>;
-
-  /**
-   * Delete a record from the store.
-   */
-  delete(
-    collectionName: string,
-    id: string,
-  ): AsyncResult<void, StoreQueryError>;
-}

packages/fabric/core/src/time/posix-date.ts

@@ -1,9 +1,38 @@
+import { isRecord } from "../record/is-record.js";
 import { TaggedVariant } from "../variant/variant.js";
 
 export class PosixDate {
-  constructor(public readonly timestamp: number) {}
+  constructor(public readonly timestamp: number = Date.now()) {}
+
+  public toJSON(): PosixDateJSON {
+    return {
+      type: "posix-date",
+      timestamp: this.timestamp,
+    };
+  }
+
+  public static fromJson(json: PosixDateJSON): PosixDate {
+    return new PosixDate(json.timestamp);
+  }
+
+  public static isPosixDateJSON(value: unknown): value is PosixDateJSON {
+    if (
+      isRecord(value) &&
+      "type" in value &&
+      "timestamp" in value &&
+      value["type"] === "posix-date" &&
+      typeof value["timestamp"] === "number"
+    )
+      return true;
+    return false;
+  }
 }
 
 export interface TimeZone extends TaggedVariant<"TimeZone"> {
   timestamp: number;
 }
+
+export interface PosixDateJSON {
+  type: "posix-date";
+  timestamp: number;
+}

packages/fabric/core/src/types/enum.ts

@@ -1 +1 @@
-export type EnumToValues<T extends Record<string, string>> = T[keyof T];
+export type EnumToType<T extends Record<string, string>> = T[keyof T];

packages/fabric/core/src/types/index.ts

@@ -3,3 +3,4 @@ export * from "./fn.js";
 export * from "./keyof.js";
 export * from "./maybe-promise.js";
 export * from "./optional.js";
+export * from "./record.js";

packages/fabric/core/src/types/record.ts

@@ -0,0 +1 @@
+export type EmptyRecord = Record<string, never>;

packages/fabric/core/src/utils/ensure-value.ts

@@ -0,0 +1,8 @@
+import { UnexpectedError } from "../error/unexpected-error.js";
+
+export function ensureValue<T>(value?: T): T {
+  if (!value) {
+    throw new UnexpectedError("Value is undefined");
+  }
+  return value;
+}

packages/fabric/core/src/utils/index.ts

@@ -0,0 +1 @@
+export * from "./ensure-value.js";

packages/fabric/core/src/variant/match.ts

@@ -1,17 +1,21 @@
 import { Fn } from "../types/fn.js";
 import { TaggedVariant, VariantFromTag, VariantTag } from "./variant.js";
 
-export type VariantMatcher<TVariant extends TaggedVariant<string>> = {
-  [K in TVariant[VariantTag]]: Fn<VariantFromTag<TVariant, K>>;
+export type VariantMatcher<TVariant extends TaggedVariant<string>, T> = {
+  [K in TVariant[VariantTag]]: Fn<VariantFromTag<TVariant, K>, T>;
 };
 
 export function match<const TVariant extends TaggedVariant<string>>(
   v: TVariant,
 ) {
   return {
-    case<const TMatcher extends VariantMatcher<TVariant>>(
-      cases: TMatcher,
-    ): ReturnType<TMatcher[TVariant[VariantTag]]> {
+    case<
+      const TReturnType,
+      const TMatcher extends VariantMatcher<
+        TVariant,
+        TReturnType
+      > = VariantMatcher<TVariant, TReturnType>,
+    >(cases: TMatcher): TReturnType {
       if (!(v[VariantTag] in cases)) {
         throw new Error("Non-exhaustive pattern match");
       }

packages/fabric/core/src/variant/variant.spec.ts

@@ -0,0 +1,41 @@
+import { describe, expect, expectTypeOf, it } from "vitest";
+import { TaggedVariant, Variant, VariantTag } from "./variant.js";
+
+interface SuccessVariant extends TaggedVariant<"success"> {
+  [VariantTag]: "success";
+  data: string;
+}
+
+interface ErrorVariant extends TaggedVariant<"error"> {
+  [VariantTag]: "error";
+  message: string;
+}
+
+describe("Variant", () => {
+  describe("isVariant", () => {
+    const successVariant = {
+      [VariantTag]: "success",
+      data: "Operation successful",
+    } as SuccessVariant | ErrorVariant;
+
+    const errorVariant = {
+      [VariantTag]: "error",
+      message: "Operation failed",
+    } as SuccessVariant | ErrorVariant;
+
+    it("should return true for a matching tag and correctly infer it", () => {
+      if (Variant.is(successVariant, "success")) {
+        expectTypeOf(successVariant).toEqualTypeOf<SuccessVariant>();
+      }
+
+      if (Variant.is(errorVariant, "error")) {
+        expectTypeOf(errorVariant).toEqualTypeOf<ErrorVariant>();
+      }
+    });
+
+    it("should return false for a non-matching tag", () => {
+      expect(Variant.is(successVariant, "error")).toBe(false);
+      expect(Variant.is(errorVariant, "success")).toBe(false);
+    });
+  });
+});

packages/fabric/core/src/variant/variant.ts

@@ -7,5 +7,17 @@ export interface TaggedVariant<TTag extends string> {
 
 export type VariantFromTag<
   TVariant extends TaggedVariant<string>,
-  TTag extends TVariant[typeof VariantTag],
+  TTag extends TVariant[VariantTag],
 > = Extract<TVariant, { [VariantTag]: TTag }>;
+
+export namespace Variant {
+  export function is<
+    TVariant extends TaggedVariant<string>,
+    TTag extends TVariant[VariantTag],
+  >(
+    variant: TVariant,
+    tag: TTag,
+  ): variant is Extract<TVariant, { [VariantTag]: TTag }> {
+    return variant[VariantTag] === tag;
+  }
+}

packages/fabric/core/vitest.config.ts

@@ -3,7 +3,7 @@ import { defineConfig } from "vitest/config";
 export default defineConfig({
   test: {
     coverage: {
-      exclude: ["**/index.ts"],
+      exclude: ["dist/**", "vitest.config.ts", "**/index.ts", "**/*.spec.ts"],
     },
     passWithNoTests: true,
   },

packages/fabric/domain/README.md

@@ -0,0 +1 @@
+# model

packages/fabric/domain/package.json

@@ -0,0 +1,30 @@
+{
+  "name": "@fabric/domain",
+  "private": true,
+  "sideEffects": false,
+  "type": "module",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": "./dist/index.js",
+    "./mocks": "./dist/mocks.js"
+  },
+  "files": [
+    "dist"
+  ],
+  "packageManager": "yarn@4.1.1",
+  "devDependencies": {
+    "@vitest/coverage-v8": "^2.1.2",
+    "typescript": "^5.6.3",
+    "vitest": "^2.1.2"
+  },
+  "dependencies": {
+    "@fabric/core": "workspace:^",
+    "decimal.js": "^10.4.3"
+  },
+  "scripts": {
+    "test": "vitest",
+    "coverage": "vitest run --coverage",
+    "build": "tsc -p tsconfig.build.json"
+  }
+}

packages/fabric/domain/src/errors/circular-dependency-error.ts

@@ -1,4 +1,4 @@
-import { TaggedError } from "../../error/tagged-error.js";
+import { TaggedError } from "@fabric/core";
 
 export class CircularDependencyError extends TaggedError<"CircularDependencyError"> {
   context: { key: string; dep: string };

packages/fabric/domain/src/errors/query-error.ts

@@ -0,0 +1,7 @@
+import { TaggedError } from "@fabric/core";
+
+export class StoreQueryError extends TaggedError<"StoreQueryError"> {
+  constructor(public message: string) {
+    super("StoreQueryError", message);
+  }
+}

packages/fabric/domain/src/events/event-store.ts

@@ -0,0 +1,42 @@
+import {
+  AsyncResult,
+  MaybePromise,
+  PosixDate,
+  VariantFromTag,
+  VariantTag,
+} from "@fabric/core";
+import { StoreQueryError } from "../errors/query-error.js";
+import { UUID } from "../types/uuid.js";
+import { Event } from "./event.js";
+import { StoredEvent } from "./stored-event.js";
+
+export interface EventStore<TEvents extends Event> {
+  /**
+   * Store a new event in the event store.
+   */
+  append<T extends TEvents>(
+    event: T,
+  ): AsyncResult<StoredEvent<T>, StoreQueryError>;
+
+  getEventsFromStream(
+    streamId: UUID,
+  ): AsyncResult<StoredEvent<TEvents>[], StoreQueryError>;
+
+  subscribe<TEventKey extends TEvents[VariantTag]>(
+    events: TEventKey[],
+    subscriber: EventSubscriber<VariantFromTag<TEvents, TEventKey>>,
+  ): void;
+}
+
+export type EventSubscriber<TEvents extends Event = Event> = (
+  event: StoredEvent<TEvents>,
+) => MaybePromise<void>;
+
+export interface EventFilterOptions {
+  fromDate?: PosixDate;
+  toDate?: PosixDate;
+  fromVersion?: bigint;
+  toVersion?: bigint;
+  limit?: number;
+  offset?: number;
+}

packages/fabric/domain/src/events/event.ts

@@ -0,0 +1,18 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+import { VariantTag } from "@fabric/core";
+import { UUID } from "../types/uuid.js";
+
+/**
+ * An event is a tagged variant with a payload and a timestamp.
+ */
+export interface Event<TTag extends string = string, TPayload = any> {
+  readonly [VariantTag]: TTag;
+  readonly id: UUID;
+  readonly streamId: UUID;
+  readonly payload: TPayload;
+}
+
+export type EventFromKey<
+  TEvents extends Event,
+  TKey extends TEvents[VariantTag],
+> = Extract<TEvents, { [VariantTag]: TKey }>;

packages/fabric/domain/src/events/index.ts

@@ -0,0 +1,3 @@
+export * from "./event-store.js";
+export * from "./event.js";
+export * from "./stored-event.js";

packages/fabric/domain/src/events/stored-event.ts

@@ -0,0 +1,10 @@
+import { PosixDate } from "@fabric/core";
+import { Event } from "./event.js";
+
+/**
+ * A stored event is an inmutable event, already stored, with it's version in the stream and timestamp.
+ */
+export type StoredEvent<TEvent extends Event> = TEvent & {
+  readonly version: bigint;
+  readonly timestamp: PosixDate;
+};

packages/fabric/domain/src/files/image-file.ts

@@ -0,0 +1,9 @@
+import { ImageMimeType } from "./mime-type.js";
+import { StoredFile } from "./stored-file.js";
+
+/**
+ * Represents an image file.
+ */
+export interface ImageFile extends StoredFile {
+  mimeType: ImageMimeType;
+}

packages/fabric/domain/src/files/in-memory-file.ts

@@ -1,4 +1,4 @@
-import { Base64String } from "../domain/types/base-64.js";
+import { Base64String } from "../types/base-64.js";
 import { BaseFile } from "./base-file.js";
 
 /**

packages/fabric/domain/src/files/index.ts

@@ -1,8 +1,10 @@
 export * from "./base-file.js";
 export * from "./bytes.js";
+export * from "./image-file.js";
+export * from "./in-memory-file.js";
 export * from "./invalid-file-type-error.js";
+export * from "./is-in-memory-file.js";
 export * from "./is-mime-type.js";
-export * from "./is-uploaded-file.js";
 export * from "./media-file.js";
 export * from "./mime-type.js";
-export * from "./uploaded-file.js";
+export * from "./stored-file.js";

packages/fabric/domain/src/files/invalid-file-type-error.ts

@@ -1,4 +1,4 @@
-import { TaggedError } from "../error/tagged-error.js";
+import { TaggedError } from "@fabric/core";
 
 export class InvalidFileTypeError extends TaggedError<"InvalidFileTypeError"> {
   constructor() {

packages/fabric/domain/src/files/is-in-memory-file.ts

@@ -1,8 +1,5 @@
-import validator from "validator";
-import { isRecord } from "../record/is-record.js";
-import { InMemoryFile } from "./uploaded-file.js";
-
-const { isBase64, isMimeType } = validator;
+import { isRecord } from "@fabric/core";
+import { InMemoryFile } from "./in-memory-file.js";
 
 export function isInMemoryFile(value: unknown): value is InMemoryFile {
   try {
@@ -10,10 +7,8 @@ export function isInMemoryFile(value: unknown): value is InMemoryFile {
       isRecord(value) &&
       "data" in value &&
       typeof value.data === "string" &&
-      isBase64(value.data.split(",")[1]) &&
       "mimeType" in value &&
       typeof value.mimeType === "string" &&
-      isMimeType(value.mimeType) &&
       "name" in value &&
       typeof value.name === "string" &&
       "sizeInBytes" in value &&

packages/fabric/domain/src/files/media-file.ts

@@ -1,8 +1,8 @@
-import { DomainFile } from "../domain/entity/files/domain-file.js";
+import { StoredFile } from "./stored-file.js";
 
 /**
  * Represents a media file, either an image, a video or an audio file.
  */
-export interface MediaFile extends DomainFile {
+export interface MediaFile extends StoredFile {
   mimeType: `image/${string}` | `video/${string}` | `audio/${string}`;
 }

packages/fabric/domain/src/files/stored-file.ts

@@ -0,0 +1,9 @@
+import { Entity } from "../types/entity.js";
+import { BaseFile } from "./base-file.js";
+
+/**
+ * Represents a file as managed by the domain.
+ */
+export interface StoredFile extends BaseFile, Entity {
+  url: string;
+}

packages/fabric/domain/src/index.ts

@@ -0,0 +1,9 @@
+export * from "./errors/index.js";
+export * from "./events/index.js";
+export * from "./files/index.js";
+export * from "./models/index.js";
+export * from "./security/index.js";
+export * from "./services/index.js";
+export * from "./types/index.js";
+export * from "./use-case/index.js";
+export * from "./utils/index.js";

packages/fabric/domain/src/mocks.ts

@@ -0,0 +1 @@
+export * from "./services/mocks.js";

packages/fabric/domain/src/models/fields/decimal.ts

@@ -0,0 +1,21 @@
+import { TaggedVariant, VariantTag } from "@fabric/core";
+import { BaseField } from "./base-field.js";
+
+export interface DecimalFieldOptions extends BaseField {
+  isUnsigned?: boolean;
+  precision?: number;
+  scale?: number;
+}
+
+export interface DecimalField
+  extends TaggedVariant<"DecimalField">,
+    DecimalFieldOptions {}
+
+export function createDecimalField<T extends DecimalFieldOptions>(
+  opts: T = {} as T,
+): DecimalField & T {
+  return {
+    [VariantTag]: "DecimalField",
+    ...opts,
+  } as const;
+}

packages/fabric/domain/src/models/fields/embedded.ts

@@ -0,0 +1,20 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+import { TaggedVariant, VariantTag } from "@fabric/core";
+import { BaseField } from "./base-field.js";
+
+// eslint-disable-next-line @typescript-eslint/no-empty-object-type, @typescript-eslint/no-unused-vars
+export interface EmbeddedFieldOptions<T = any> extends BaseField {}
+
+export interface EmbeddedField<T = any>
+  extends TaggedVariant<"EmbeddedField">,
+    EmbeddedFieldOptions<T> {}
+
+export function createEmbeddedField<
+  K = any,
+  T extends EmbeddedFieldOptions<K> = EmbeddedFieldOptions<K>,
+>(opts: T = {} as T): EmbeddedField & T {
+  return {
+    [VariantTag]: "EmbeddedField",
+    ...opts,
+  } as const;
+}

packages/fabric/domain/src/models/fields/field-to-type.ts

@@ -0,0 +1,37 @@
+import { PosixDate } from "@fabric/core";
+import { Decimal } from "decimal.js";
+import { UUID } from "../../types/uuid.js";
+import { DecimalField } from "./decimal.js";
+import { EmbeddedField } from "./embedded.js";
+import { FloatField } from "./float.js";
+import { IntegerField } from "./integer.js";
+import { ReferenceField } from "./reference-field.js";
+import { StringField } from "./string-field.js";
+import { TimestampField } from "./timestamp.js";
+import { UUIDField } from "./uuid-field.js";
+
+/**
+ * Converts a field definition to its corresponding TypeScript type.
+ */
+//prettier-ignore
+export type FieldToType<TField> = 
+    TField extends StringField ? MaybeOptional<TField, string>
+  : TField extends UUIDField ? MaybeOptional<TField, UUID>
+  : TField extends IntegerField ? IntegerFieldToType<TField>
+  : TField extends ReferenceField ? MaybeOptional<TField, UUID>
+  : TField extends DecimalField ? MaybeOptional<TField, Decimal>
+  : TField extends FloatField ? MaybeOptional<TField, number>
+  : TField extends TimestampField ? MaybeOptional<TField, PosixDate>
+  : TField extends EmbeddedField<infer TSubModel> ? MaybeOptional<TField, TSubModel>
+  : never;
+
+//prettier-ignore
+type IntegerFieldToType<TField extends IntegerField> = TField["hasArbitraryPrecision"] extends true
+  ? MaybeOptional<TField, bigint>
+  : TField["hasArbitraryPrecision"] extends false
+  ? MaybeOptional<TField, number>
+  : MaybeOptional<TField, number | bigint>;
+
+type MaybeOptional<TField, TType> = TField extends { isOptional: true }
+  ? TType | null
+  : TType;

packages/fabric/domain/src/models/fields/float.ts

@@ -0,0 +1,18 @@
+import { TaggedVariant, VariantTag } from "@fabric/core";
+import { BaseField } from "./base-field.js";
+
+// eslint-disable-next-line @typescript-eslint/no-empty-object-type
+export interface FloatFieldOptions extends BaseField {}
+
+export interface FloatField
+  extends TaggedVariant<"FloatField">,
+    FloatFieldOptions {}
+
+export function createFloatField<T extends FloatFieldOptions>(
+  opts: T = {} as T,
+): FloatField & T {
+  return {
+    [VariantTag]: "FloatField",
+    ...opts,
+  } as const;
+}

packages/fabric/domain/src/models/fields/index.ts

@@ -0,0 +1,32 @@
+import { createDecimalField, DecimalField } from "./decimal.js";
+import { createEmbeddedField, EmbeddedField } from "./embedded.js";
+import { createFloatField, FloatField } from "./float.js";
+import { createIntegerField, IntegerField } from "./integer.js";
+import { createReferenceField, ReferenceField } from "./reference-field.js";
+import { createStringField, StringField } from "./string-field.js";
+import { createTimestampField, TimestampField } from "./timestamp.js";
+import { createUUIDField, UUIDField } from "./uuid-field.js";
+export * from "./base-field.js";
+export * from "./field-to-type.js";
+export * from "./reference-field.js";
+
+export type FieldDefinition =
+  | StringField
+  | UUIDField
+  | IntegerField
+  | FloatField
+  | DecimalField
+  | ReferenceField
+  | TimestampField
+  | EmbeddedField;
+
+export namespace Field {
+  export const string = createStringField;
+  export const uuid = createUUIDField;
+  export const integer = createIntegerField;
+  export const reference = createReferenceField;
+  export const decimal = createDecimalField;
+  export const float = createFloatField;
+  export const timestamp = createTimestampField;
+  export const embedded = createEmbeddedField;
+}

packages/fabric/domain/src/models/fields/integer.ts

@@ -0,0 +1,20 @@
+import { TaggedVariant, VariantTag } from "@fabric/core";
+import { BaseField } from "./base-field.js";
+
+export interface IntegerFieldOptions extends BaseField {
+  isUnsigned?: boolean;
+  hasArbitraryPrecision?: boolean;
+}
+
+export interface IntegerField
+  extends TaggedVariant<"IntegerField">,
+    IntegerFieldOptions {}
+
+export function createIntegerField<T extends IntegerFieldOptions>(
+  opts: T = {} as T,
+): IntegerField & T {
+  return {
+    [VariantTag]: "IntegerField",
+    ...opts,
+  } as const;
+}

packages/fabric/domain/src/models/fields/reference-field.spec.ts

@@ -0,0 +1,80 @@
+import { isError } from "@fabric/core";
+import { describe, expect, it } from "vitest";
+import { defineModel } from "../model.js";
+import { Field } from "./index.js";
+import {
+  InvalidReferenceFieldError,
+  validateReferenceField,
+} from "./reference-field.js";
+
+describe("Validate Reference Field", () => {
+  const schema = {
+    User: defineModel("User", {
+      name: Field.string(),
+      password: Field.string(),
+      otherUnique: Field.integer({ isUnique: true }),
+      otherNotUnique: Field.uuid(),
+      otherUser: Field.reference({
+        targetModel: "User",
+      }),
+    }),
+  };
+
+  it("should return an error when the target model is not in the schema", () => {
+    const result = validateReferenceField(
+      schema,
+      Field.reference({
+        targetModel: "foo",
+      }),
+    ).unwrapErrorOrThrow();
+
+    expect(result).toBeInstanceOf(InvalidReferenceFieldError);
+  });
+
+  it("should not return an error if the target model is in the schema", () => {
+    validateReferenceField(
+      schema,
+      Field.reference({
+        targetModel: "User",
+      }),
+    ).unwrapOrThrow();
+  });
+
+  it("should return an error if the target key is not in the target model", () => {
+    const result = validateReferenceField(
+      schema,
+      Field.reference({
+        targetModel: "User",
+        targetKey: "foo",
+      }),
+    ).unwrapErrorOrThrow();
+
+    expect(result).toBeInstanceOf(InvalidReferenceFieldError);
+  });
+
+  it("should return error if the target key is not unique", () => {
+    const result = validateReferenceField(
+      schema,
+      Field.reference({
+        targetModel: "User",
+        targetKey: "otherNotUnique",
+      }),
+    ).unwrapErrorOrThrow();
+
+    expect(result).toBeInstanceOf(InvalidReferenceFieldError);
+  });
+
+  it("should not return an error if the target key is in the target model and is unique", () => {
+    const result = validateReferenceField(
+      schema,
+      Field.reference({
+        targetModel: "User",
+        targetKey: "otherUnique",
+      }),
+    );
+
+    if (isError(result)) {
+      throw result.toString();
+    }
+  });
+});

packages/fabric/domain/src/models/fields/reference-field.ts

@@ -0,0 +1,65 @@
+import { Result, TaggedError, TaggedVariant, VariantTag } from "@fabric/core";
+import { ModelSchema } from "../model-schema.js";
+import { BaseField } from "./base-field.js";
+
+export interface ReferenceFieldOptions extends BaseField {
+  targetModel: string;
+  targetKey?: string;
+}
+
+export interface ReferenceField
+  extends TaggedVariant<"ReferenceField">,
+    ReferenceFieldOptions {}
+
+export function createReferenceField<T extends ReferenceFieldOptions>(
+  opts: T = {} as T,
+): ReferenceField & T {
+  return {
+    [VariantTag]: "ReferenceField",
+    ...opts,
+  } as const;
+}
+
+export function getTargetKey(field: ReferenceField): string {
+  return field.targetKey || "id";
+}
+
+export function validateReferenceField(
+  schema: ModelSchema,
+  field: ReferenceField,
+): Result<void, InvalidReferenceFieldError> {
+  if (!schema[field.targetModel]) {
+    return Result.failWith(
+      new InvalidReferenceFieldError(
+        `The target model '${field.targetModel}' is not in the schema.`,
+      ),
+    );
+  }
+
+  if (field.targetKey && !schema[field.targetModel].fields[field.targetKey]) {
+    return Result.failWith(
+      new InvalidReferenceFieldError(
+        `The target key '${field.targetKey}' is not in the target model '${field.targetModel}'.`,
+      ),
+    );
+  }
+
+  if (
+    field.targetKey &&
+    !schema[field.targetModel].fields[field.targetKey].isUnique
+  ) {
+    return Result.failWith(
+      new InvalidReferenceFieldError(
+        `The target key '${field.targetModel}'.'${field.targetKey}' is not unique.`,
+      ),
+    );
+  }
+
+  return Result.ok();
+}
+
+export class InvalidReferenceFieldError extends TaggedError<"InvalidReferenceField"> {
+  constructor(readonly reason: string) {
+    super("InvalidReferenceField");
+  }
+}

packages/fabric/domain/src/models/fields/string-field.ts

@@ -1,4 +1,4 @@
-import { TaggedVariant, VariantTag } from "../../../variant/variant.js";
+import { TaggedVariant, VariantTag } from "@fabric/core";
 import { BaseField } from "./base-field.js";
 
 export interface StringFieldOptions extends BaseField {

packages/fabric/domain/src/models/fields/timestamp.ts

@@ -0,0 +1,18 @@
+import { TaggedVariant, VariantTag } from "@fabric/core";
+import { BaseField } from "./base-field.js";
+
+// eslint-disable-next-line @typescript-eslint/no-empty-object-type
+export interface TimestampFieldOptions extends BaseField {}
+
+export interface TimestampField
+  extends TaggedVariant<"TimestampField">,
+    TimestampFieldOptions {}
+
+export function createTimestampField<T extends TimestampFieldOptions>(
+  opts: T = {} as T,
+): TimestampField & T {
+  return {
+    [VariantTag]: "TimestampField",
+    ...opts,
+  } as const;
+}

packages/fabric/domain/src/models/fields/uuid-field.ts

@@ -0,0 +1,19 @@
+import { TaggedVariant, VariantTag } from "@fabric/core";
+import { BaseField } from "./base-field.js";
+
+export interface UUIDFieldOptions extends BaseField {
+  isPrimaryKey?: boolean;
+}
+
+export interface UUIDField
+  extends TaggedVariant<"UUIDField">,
+    UUIDFieldOptions {}
+
+export function createUUIDField<T extends UUIDFieldOptions>(
+  opts: T = {} as T,
+): UUIDField & T {
+  return {
+    [VariantTag]: "UUIDField",
+    ...opts,
+  } as const;
+}

packages/fabric/domain/src/models/index.ts

@@ -0,0 +1,5 @@
+export * from "./fields/index.js";
+export * from "./model-schema.js";
+export * from "./model.js";
+export * from "./query/index.js";
+export * from "./state-store.js";

packages/fabric/domain/src/models/model-schema.ts

@@ -0,0 +1,7 @@
+import { Model } from "./model.js";
+
+export type ModelSchema = Record<string, Model>;
+
+export type ModelSchemaFromModels<TModels extends Model> = {
+  [K in TModels["name"]]: Extract<TModels, { name: K }>;
+};

packages/fabric/domain/src/models/model.spec.ts

@@ -0,0 +1,24 @@
+import { describe, expectTypeOf, it } from "vitest";
+import { UUID } from "../types/uuid.js";
+import { Field } from "./fields/index.js";
+import { defineModel, ModelToType } from "./model.js";
+
+describe("CreateModel", () => {
+  it("should create a model and it's interface type", () => {
+    const User = defineModel("User", {
+      name: Field.string(),
+      password: Field.string(),
+      phone: Field.string({ isOptional: true }),
+    });
+    type User = ModelToType<typeof User>;
+
+    expectTypeOf<User>().toEqualTypeOf<{
+      id: UUID;
+      streamId: UUID;
+      streamVersion: bigint;
+      name: string;
+      password: string;
+      phone: string | null;
+    }>();
+  });
+});

packages/fabric/domain/src/models/model.ts

@@ -0,0 +1,64 @@
+import { Keyof } from "@fabric/core";
+import { FieldToType } from "./fields/field-to-type.js";
+import { Field, FieldDefinition } from "./fields/index.js";
+
+export type CustomModelFields = Record<string, FieldDefinition>;
+
+export interface Collection<
+  TName extends string = string,
+  TFields extends CustomModelFields = CustomModelFields,
+> {
+  name: TName;
+  fields: TFields;
+}
+
+export const DefaultModelFields = {
+  id: Field.uuid({ isPrimaryKey: true }),
+  streamId: Field.uuid({ isIndexed: true }),
+  streamVersion: Field.integer({
+    isUnsigned: true,
+    hasArbitraryPrecision: true,
+  }),
+  deletedAt: Field.timestamp({ isOptional: true }),
+};
+
+export interface Model<
+  TName extends string = string,
+  TFields extends CustomModelFields = CustomModelFields,
+> extends Collection<TName, TFields> {
+  fields: typeof DefaultModelFields & TFields;
+}
+
+export function defineModel<
+  TName extends string,
+  TFields extends CustomModelFields,
+>(name: TName, fields: TFields): Model<TName, TFields> {
+  return {
+    name,
+    fields: { ...DefaultModelFields, ...fields },
+  } as const;
+}
+
+export function defineCollection<
+  TName extends string,
+  TFields extends CustomModelFields,
+>(name: TName, fields: TFields): Collection<TName, TFields> {
+  return {
+    name,
+    fields,
+  } as const;
+}
+
+export type ModelToType<TModel extends Collection> = {
+  [K in Keyof<TModel["fields"]>]: FieldToType<TModel["fields"][K]>;
+};
+
+export type ModelFieldNames<TModel extends CustomModelFields> = Keyof<
+  TModel["fields"]
+>;
+
+export type ModelAddressableFields<TModel extends Model> = {
+  [K in Keyof<TModel["fields"]>]: TModel["fields"][K] extends { isUnique: true }
+    ? K
+    : never;
+}[Keyof<TModel["fields"]>];

packages/fabric/domain/src/models/query/aggregate-options.ts

@@ -0,0 +1,24 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+import { Keyof, TaggedVariant } from "@fabric/core";
+
+export type AggregateOptions<T = any> = Record<string, AggregateFn<T>>;
+
+export type AggregateFn<T> = CountAggregate<T>;
+
+export interface CountAggregate<T> extends TaggedVariant<"AggregateCount"> {
+  field: Keyof<T>;
+}
+export interface SumAggregate<T> extends TaggedVariant<"AggregateSum"> {
+  field: Keyof<T>;
+}
+export interface AvgAggregate<T> extends TaggedVariant<"AggregateAvg"> {
+  field: Keyof<T>;
+}
+
+export interface MinAggregate<T> extends TaggedVariant<"AggregateMin"> {
+  field: Keyof<T>;
+}
+export interface MaxAggregate<T> extends TaggedVariant<"AggregateMax"> {
+  field: Keyof<T>;
+}

packages/fabric/domain/src/models/query/filter-options.ts

@@ -4,19 +4,21 @@ export type FilterOptions<T = any> =
   | SingleFilterOption<T>
   | MultiFilterOption<T>;
 
+export type FilterValue<T = any, K extends keyof T = keyof T> =
+  | T[K]
+  | LikeFilterOption<T[K]>
+  | ComparisonFilterOption<T[K]>
+  | InFilterOption<T[K]>;
+
 export type SingleFilterOption<T = any> = {
-  [K in keyof T]?:
-    | T[K]
-    | LikeFilterOption<T[K]>
-    | ComparisonFilterOption<T[K]>
-    | InFilterOption<T[K]>;
+  [K in keyof T]?: FilterValue<T, K>;
 };
 
 export type MultiFilterOption<T = any> = SingleFilterOption<T>[];
 
-export const FILTER_OPTION_TYPE_SYMBOL = Symbol("$type");
-export const FILTER_OPTION_VALUE_SYMBOL = Symbol("$value");
-export const FILTER_OPTION_OPERATOR_SYMBOL = Symbol("$operator");
+export const FILTER_OPTION_TYPE_SYMBOL = "_filter_type";
+export const FILTER_OPTION_VALUE_SYMBOL = "_filter_value";
+export const FILTER_OPTION_OPERATOR_SYMBOL = "_filter_operator";
 
 export type LikeFilterOption<T> = T extends string
   ? {

packages/fabric/domain/src/models/query/index.ts

@@ -1,4 +1,3 @@
 export * from "./filter-options.js";
 export * from "./order-by-options.js";
-export * from "./query-builder.js";
 export * from "./query.js";

packages/fabric/domain/src/models/query/query.ts

@@ -1,7 +1,6 @@
 /* eslint-disable @typescript-eslint/no-explicit-any */
-import { AsyncResult } from "../../result/async-result.js";
-import { Keyof } from "../../types/keyof.js";
-import { StoreQueryError } from "../errors/query-error.js";
+import { AsyncResult, Keyof, Optional } from "@fabric/core";
+import { StoreQueryError } from "../../errors/query-error.js";
 import { FilterOptions } from "./filter-options.js";
 import { OrderByOptions } from "./order-by-options.js";
 
@@ -15,10 +14,10 @@ export interface StoreQuery<T> {
     keys: K[],
   ): AsyncResult<Pick<T, K>[], StoreQueryError>;
 
-  selectOne(): AsyncResult<T, StoreQueryError>;
+  selectOne(): AsyncResult<Optional<T>, StoreQueryError>;
   selectOne<K extends Keyof<T>>(
     keys: K[],
-  ): AsyncResult<Pick<T, K>, StoreQueryError>;
+  ): AsyncResult<Optional<Pick<T, K>>, StoreQueryError>;
 }
 
 export interface StoreSortableQuery<T> {
@@ -30,10 +29,10 @@ export interface StoreSortableQuery<T> {
     keys: K[],
   ): AsyncResult<Pick<T, K>[], StoreQueryError>;
 
-  selectOne(): AsyncResult<T, StoreQueryError>;
+  selectOne(): AsyncResult<Optional<T>, StoreQueryError>;
   selectOne<K extends Keyof<T>>(
     keys: K[],
-  ): AsyncResult<Pick<T, K>, StoreQueryError>;
+  ): AsyncResult<Optional<Pick<T, K>>, StoreQueryError>;
 }
 
 export interface StoreLimitableQuery<T> {
@@ -44,10 +43,10 @@ export interface StoreLimitableQuery<T> {
     keys: K[],
   ): AsyncResult<Pick<T, K>[], StoreQueryError>;
 
-  selectOne(): AsyncResult<T, StoreQueryError>;
+  selectOne(): AsyncResult<Optional<T>, StoreQueryError>;
   selectOne<K extends Keyof<T>>(
     keys: K[],
-  ): AsyncResult<Pick<T, K>, StoreQueryError>;
+  ): AsyncResult<Optional<Pick<T, K>>, StoreQueryError>;
 }
 
 export interface SelectableQuery<T> {
@@ -56,10 +55,10 @@ export interface SelectableQuery<T> {
     keys: K[],
   ): AsyncResult<Pick<T, K>[], StoreQueryError>;
 
-  selectOne(): AsyncResult<T, StoreQueryError>;
+  selectOne(): AsyncResult<Optional<T>, StoreQueryError>;
   selectOne<K extends Keyof<T>>(
     keys: K[],
-  ): AsyncResult<Pick<T, K>, StoreQueryError>;
+  ): AsyncResult<Optional<Pick<T, K>>, StoreQueryError>;
 }
 
 export interface QueryDefinition<K extends string = string> {

packages/fabric/domain/src/models/state-store.ts

@@ -0,0 +1,19 @@
+import { AsyncResult } from "@fabric/core";
+import { StoreQueryError } from "../errors/query-error.js";
+import { ModelSchemaFromModels } from "./model-schema.js";
+import { Model, ModelToType } from "./model.js";
+import { StoreQuery } from "./query/query.js";
+
+export interface ReadonlyStateStore<TModel extends Model> {
+  from<T extends keyof ModelSchemaFromModels<TModel>>(
+    collection: T,
+  ): StoreQuery<ModelToType<ModelSchemaFromModels<TModel>[T]>>;
+}
+
+export interface WritableStateStore<TModel extends Model>
+  extends ReadonlyStateStore<TModel> {
+  insertInto<T extends keyof ModelSchemaFromModels<TModel>>(
+    collection: T,
+    record: ModelToType<ModelSchemaFromModels<TModel>[T]>,
+  ): AsyncResult<void, StoreQueryError>;
+}

packages/fabric/domain/src/projections/projection.ts

@@ -0,0 +1,13 @@
+import { VariantTag } from "@fabric/core";
+import { Event } from "../events/event.js";
+import { StoredEvent } from "../events/stored-event.js";
+import { Model, ModelToType } from "../models/model.js";
+
+export interface Projection<TModel extends Model, TEvents extends Event> {
+  model: TModel;
+  events: TEvents[VariantTag][];
+  projection: (
+    event: StoredEvent<TEvents>,
+    model?: ModelToType<TModel>,
+  ) => ModelToType<TModel>;
+}

packages/fabric/domain/src/services/index.ts

@@ -0,0 +1 @@
+export * from "./uuid-generator.js";

packages/fabric/domain/src/services/mocks.ts

@@ -0,0 +1 @@
+export * from "./uuid-generator.mock.js";

packages/fabric/domain/src/services/uuid-generator.mock.ts

@@ -0,0 +1,8 @@
+import { UUID } from "../types/uuid.js";
+import { UUIDGenerator } from "./uuid-generator.js";
+
+export const UUIDGeneratorMock: UUIDGenerator = {
+  generate(): UUID {
+    return crypto.randomUUID() as UUID;
+  },
+};

packages/fabric/domain/src/services/uuid-generator.ts

@@ -0,0 +1,5 @@
+import { UUID } from "../types/uuid.js";
+
+export interface UUIDGenerator {
+  generate(): UUID;
+}

packages/fabric/domain/src/types/decimal.ts

@@ -0,0 +1 @@
+export { Decimal } from "decimal.js";