Add reward module endpoint - Closes #6689

framework/src/modules/reward/calculate_reward.ts

@@ -0,0 +1,31 @@
+/*
+ * Copyright © 2021 Lisk Foundation
+ *
+ * See the LICENSE file at the top-level directory of this distribution
+ * for licensing information.
+ *
+ * Unless otherwise agreed in a custom licensing agreement with the Lisk Foundation,
+ * no part of this software, including this file, may be copied, modified,
+ * propagated, or distributed except according to the terms contained in the
+ * LICENSE file.
+ *
+ * Removal or modification of this copyright notice is prohibited.
+ */
+
+import { CalculateDefaultRewardArgs } from './types';
+
+export const calculateDefaultReward = (args: CalculateDefaultRewardArgs): bigint => {
+	const { height, distance, offset, brackets } = args;
+
+	if (height < offset) {
+		return BigInt(0);
+	}
+
+	const rewardDistance = Math.floor(distance);
+	const location = Math.trunc((height - offset) / rewardDistance);
+	const lastBracket = brackets[brackets.length - 1];
+
+	const bracket = location > brackets.length - 1 ? brackets.lastIndexOf(lastBracket) : location;
+
+	return brackets[bracket];
+};

framework/src/modules/reward/endpoint.ts

@@ -12,6 +12,40 @@
  * Removal or modification of this copyright notice is prohibited.
  */
 
+import { ModuleEndpointContext } from '../..';
 import { BaseEndpoint } from '../base_endpoint';
+import { calculateDefaultReward } from './calculate_reward';
+import { DefaultReward, EndpointInitArgs } from './types';
 
-export class RewardEndpoint extends BaseEndpoint {}
+export class RewardEndpoint extends BaseEndpoint {
+	private _brackets!: ReadonlyArray<bigint>;
+	private _offset!: number;
+	private _distance!: number;
+
+	public init(args: EndpointInitArgs) {
+		this._brackets = args.config.brackets;
+		this._offset = args.config.offset;
+		this._distance = args.config.distance;
+	}
+
+	public getDefaultRewardAtHeight(ctx: ModuleEndpointContext): DefaultReward {
+		const { height } = ctx.params;
+
+		if (typeof height !== 'number') {
+			throw new Error('Parameter height must be a number.');
+		}
+
+		if (height < 0) {
+			throw new Error('Parameter height cannot be smaller than 0.');
+		}
+
+		const reward = calculateDefaultReward({
+			height,
+			brackets: this._brackets,
+			distance: this._distance,
+			offset: this._offset,
+		});
+
+		return { reward: reward.toString() };
+	}
+}

framework/src/modules/reward/module.ts

@@ -44,6 +44,14 @@ export class RewardModule extends BaseModule {
 		const { moduleConfig } = args;
 		this._moduleConfig = (moduleConfig as unknown) as ModuleConfig;
 		this._tokenIDReward = this._moduleConfig.tokenIDReward;
+
+		this.endpoint.init({
+			config: {
+				brackets: this._moduleConfig.brackets.map(bracket => BigInt(bracket)),
+				offset: this._moduleConfig.offset,
+				distance: this._moduleConfig.distance,
+			},
+		});
 	}
 
 	// eslint-disable-next-line @typescript-eslint/require-await

framework/src/modules/reward/schemas.ts

@@ -28,6 +28,21 @@ export const configSchema = {
 			},
 			required: ['chainID', 'localID'],
 		},
+		offset: {
+			type: 'integer',
+			minimum: 1,
+		},
+		distance: {
+			type: 'integer',
+			minimum: 1,
+		},
+		brackets: {
+			type: 'array',
+			items: {
+				type: 'string',
+				format: 'uint64',
+			},
+		},
 	},
-	required: ['tokenIDReward'],
+	required: ['tokenIDReward', 'offset', 'distance', 'brackets'],
 };

framework/src/modules/reward/types.ts

@@ -22,6 +22,9 @@ export interface TokenIDReward {
 
 export interface ModuleConfig {
 	tokenIDReward: TokenIDReward;
+	brackets: ReadonlyArray<string>;
+	offset: number;
+	distance: number;
 }
 
 export interface TokenAPI {
@@ -44,3 +47,22 @@ export interface RandomAPI {
 export interface LiskBFTAPI {
 	impliesMaximalPrevotes(apiContext: APIContext, blockHeader: BlockHeader): Promise<boolean>;
 }
+
+export interface DefaultReward {
+	reward: string;
+}
+
+export interface EndpointInitArgs {
+	config: {
+		brackets: ReadonlyArray<bigint>;
+		offset: number;
+		distance: number;
+	};
+}
+
+export interface CalculateDefaultRewardArgs {
+	brackets: ReadonlyArray<bigint>;
+	offset: number;
+	distance: number;
+	height: number;
+}

framework/test/unit/modules/reward/endpoint.spec.ts

@@ -0,0 +1,103 @@
+/*
+ * Copyright © 2021 Lisk Foundation
+ *
+ * See the LICENSE file at the top-level directory of this distribution
+ * for licensing information.
+ *
+ * Unless otherwise agreed in a custom licensing agreement with the Lisk Foundation,
+ * no part of this software, including this file, may be copied, modified,
+ * propagated, or distributed except according to the terms contained in the
+ * LICENSE file.
+ *
+ * Removal or modification of this copyright notice is prohibited.
+ */
+import { Logger } from '../../../../src/logger';
+import { RewardModule } from '../../../../src/modules/reward';
+import { fakeLogger } from '../../../utils/node';
+
+describe('RewardModuleEndpoint', () => {
+	const genesisConfig: any = {};
+	const moduleConfig: any = {
+		distance: 3000000,
+		offset: 2160,
+		brackets: [
+			BigInt('500000000'), // Initial Reward
+			BigInt('400000000'), // Milestone 1
+			BigInt('300000000'), // Milestone 2
+			BigInt('200000000'), // Milestone 3
+			BigInt('100000000'), // Milestone 4
+		],
+		tokenIDReward: { chainID: 0, localID: 0 },
+	};
+	const generatorConfig: any = {};
+
+	const logger: Logger = fakeLogger;
+	let rewardModule: RewardModule;
+
+	beforeAll(async () => {
+		rewardModule = new RewardModule();
+		await rewardModule.init({ genesisConfig, moduleConfig, generatorConfig });
+		rewardModule.addDependencies(
+			{ mint: jest.fn() } as any,
+			{ isValidSeedReveal: jest.fn() } as any,
+			{ impliesMaximalPrevotes: jest.fn() } as any,
+		);
+	});
+
+	const { brackets, offset, distance } = moduleConfig as {
+		brackets: ReadonlyArray<bigint>;
+		offset: number;
+		distance: number;
+	};
+
+	for (const [index, rewardFromConfig] of Object.entries(brackets)) {
+		const nthBracket = +index;
+		const currentHeight = offset + nthBracket * distance;
+		// eslint-disable-next-line no-loop-func
+		it(`should getDefaultRewardAtHeight work for the ${nthBracket}th bracket`, () => {
+			const rewardFromEndpoint = rewardModule.endpoint.getDefaultRewardAtHeight({
+				getStore: jest.fn(),
+				logger,
+				params: {
+					height: currentHeight,
+				},
+			});
+			expect(rewardFromEndpoint).toEqual({ reward: rewardFromConfig.toString() });
+		});
+	}
+
+	it('should getDefaultRewardAtHeight work for the height below offset', () => {
+		const rewardFromEndpoint = rewardModule.endpoint.getDefaultRewardAtHeight({
+			getStore: jest.fn(),
+			logger,
+			params: {
+				height: offset - 1,
+			},
+		});
+		expect(rewardFromEndpoint).toEqual({ reward: '0' });
+	});
+
+	it('should throw an error when parameter height is not a number', () => {
+		expect(() =>
+			rewardModule.endpoint.getDefaultRewardAtHeight({
+				getStore: jest.fn(),
+				logger,
+				params: {
+					height: 'Not a number',
+				},
+			}),
+		).toThrow('Parameter height must be a number.');
+	});
+
+	it('should throw an error when parameter height is below 0', () => {
+		expect(() =>
+			rewardModule.endpoint.getDefaultRewardAtHeight({
+				getStore: jest.fn(),
+				logger,
+				params: {
+					height: -1,
+				},
+			}),
+		).toThrow('Parameter height cannot be smaller than 0.');
+	});
+});

framework/test/unit/modules/reward/reward_module.spec.ts

@@ -0,0 +1,49 @@
+/*
+ * Copyright © 2021 Lisk Foundation
+ *
+ * See the LICENSE file at the top-level directory of this distribution
+ * for licensing information.
+ *
+ * Unless otherwise agreed in a custom licensing agreement with the Lisk Foundation,
+ * no part of this software, including this file, may be copied, modified,
+ * propagated, or distributed except according to the terms contained in the
+ * LICENSE file.
+ *
+ * Removal or modification of this copyright notice is prohibited.
+ */
+import { RewardModule } from '../../../../src/modules/reward';
+
+describe('RewardModule', () => {
+	const genesisConfig: any = {};
+	const moduleConfig: any = {
+		distance: 3000000,
+		offset: 2160,
+		brackets: [
+			BigInt('500000000'), // Initial Reward
+			BigInt('400000000'), // Milestone 1
+			BigInt('300000000'), // Milestone 2
+			BigInt('200000000'), // Milestone 3
+			BigInt('100000000'), // Milestone 4
+		],
+		tokenIDReward: { chainID: 0, localID: 0 },
+	};
+	const generatorConfig: any = {};
+
+	let rewardModule: RewardModule;
+
+	beforeAll(async () => {
+		rewardModule = new RewardModule();
+		await rewardModule.init({ genesisConfig, moduleConfig, generatorConfig });
+		rewardModule.addDependencies(
+			{ mint: jest.fn() } as any,
+			{ isValidSeedReveal: jest.fn() } as any,
+			{ impliesMaximalPrevotes: jest.fn() } as any,
+		);
+	});
+
+	describe('init', () => {
+		it('should set the moduleConfig property', () => {
+			expect(rewardModule['_moduleConfig']).toEqual(moduleConfig);
+		});
+	});
+});