設定

パッケージインストール

1$ npm -i aws-sdk-client-mock aws-sdk-client-mock-jest

jest.config.js

1/*
2 * For a detailed explanation regarding each configuration property, visit:
3 * https://jestjs.io/docs/configuration
4 */
5
6module.exports = {
7  clearMocks: true,
8  collectCoverage: true,
9  coverageDirectory: "coverage",
10  coveragePathIgnorePatterns: [
11    "/node_modules/"
12  ],
13  testEnvironment: 'node',
14  moduleFileExtensions: ["js","mjs","json","node",],
15  moduleNameMapper: {
16    "\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$":
17      "<rootDir>/__mocks__/fileMock.js",
18    "\\.(css|less)$": "<rootDir>/__mocks__/styleMock.js",
19  },
20  testMatch: [
21    "**/__tests__/**/*.[jt]s?(x)",
22    "**/?(*.)+(spec|test).[tj]s?(x)"
23  ],
24  testPathIgnorePatterns: [
25    "/node_modules/"
26  ],
27  transform: {
28    '^.+\\.m?js?$': 'babel-jest',
29  },
30};

DynamoDBからItem取得するコード

1import { DynamoDBDocumentClient, GetCommand } from "@aws-sdk/lib-dynamodb";
2import { DynamoDBClient } from '@aws-sdk/client-dynamodb';
3
4export const initDynamoClient = () => {
5    const marshallOptions = {
6        removeUndefinedValues: true,
7    };
8    const translateConfig = { marshallOptions };
9    const DynamoDBclient = new DynamoDBClient({
10        region: 'ap-northeast-1'
11    });
12    
13    const dynamo = DynamoDBDocumentClient.from( DynamoDBclient, translateConfig );
14    return dynamo;
15}
16
17export const response = (statusCode, body) => {
18    return {
19        statusCode: statusCode,
20        headers: {
21            "Access-Control-Allow-Headers" : "Content-Type",
22            "Access-Control-Allow-Origin": "*",
23            "Access-Control-Allow-Methods": "GET"
24        },
25        body: JSON.stringify(
26            body
27        ),
28    };
29};
30
31export const handler = async (event) => {
32    try {
33        const dynamo = initDynamoClient();
34        const id = event.pathParameters.id;
35        const dynamo_data = await dynamo.send(
36            new GetCommand({
37                TableName: "Dynamo_test",
38                Key: {
39                    id: id,
40                },
41            })
42        );
43        if (dynamo_data.Item === undefined) {
44            return response(404, {"message": "not found."});
45        } else {
46            return response(200, dynamo_data.Item);
47        }
48    } catch (error) {
49        console.log(error);
50        return {
51            statusCode: 500,
52            headers: {
53                "Access-Control-Allow-Headers" : "Content-Type",
54                "Access-Control-Allow-Origin": "*",
55                "Access-Control-Allow-Methods": "GET"
56            },
57            body: JSON.stringify({"message": "500err"}),
58        };
59    }
60};

testコード

1import { handler as getItem } from "../get_dynamo.mjs";
2import { DynamoDBDocumentClient, GetCommand } from "@aws-sdk/lib-dynamodb";
3import { mockClient } from "aws-sdk-client-mock";
4
5const ddbMock = mockClient(DynamoDBDocumentClient)
6
7describe("handler get item", () => {
8    beforeEach(() => {
9        ddbMock.reset()
10    })
11
12    it("get item test", async () => {
13        const event = {
14            "pathParameters": {
15                "id": "test"
16            }
17        };
18        const expectValue = {
19            Item: { id: "test", value: "memo" }
20        };
21        ddbMock.on(GetCommand).resolves(expectValue)
22        const result = await getItem(event)
23        expect(result).toEqual({
24            statusCode: 200,
25            headers: {
26                "Access-Control-Allow-Headers" : "Content-Type",
27                "Access-Control-Allow-Origin": "*",
28                "Access-Control-Allow-Methods": "GET"
29            },
30            body: JSON.stringify(
31                {id:"test",value:"memo"}
32            )
33        })
34    })
35
36    it("item not found test", async () => {
37        const event = {
38            "pathParameters": {
39                "id": "notfoundID"
40            }
41        };
42        const expectValue = {
43            Item: undefined
44        };
45        ddbMock.on(GetCommand).resolves(expectValue)
46        const result = await getItem(event)
47        expect(result).toEqual({
48            statusCode: 404,
49            headers: {
50                "Access-Control-Allow-Headers" : "Content-Type",
51                "Access-Control-Allow-Origin": "*",
52                "Access-Control-Allow-Methods": "GET"
53            },
54            body: JSON.stringify(
55                {"message": "not found."}
56            ),
57        });
58    })
59
60    it("handler response test", async () => {
61        const event = {
62            "pathParameters": {
63                "id": "test"
64            }
65        };
66        const expectValue = {
67            Item: { id: event.pathParameters.id, value: "memo" }
68        };
69        ddbMock.on(GetCommand).resolves(expectValue)
70        const result = await getItem(event)
71        expect(result).toEqual({
72            statusCode: 200,
73            headers: {
74                "Access-Control-Allow-Headers" : "Content-Type",
75                "Access-Control-Allow-Origin": "*",
76                "Access-Control-Allow-Methods": "GET"
77            },
78            body: JSON.stringify(
79                expectValue.Item
80            ),
81        });
82    })
83})
84
85describe("handler get item error test", () => {
86    beforeEach(() => {
87        ddbMock.reset()
88    })
89
90    it("handler error test", async () => {
91        const event = {
92            "pathParameters": {
93                "id": "test"
94            }
95        };
96        const expectValue = "ERR"
97        ddbMock.on(GetCommand).rejects(expectValue)
98        const result = await getItem(event)
99        expect(result).toEqual({
100            statusCode: 500,
101            headers: {
102                "Access-Control-Allow-Headers" : "Content-Type",
103                "Access-Control-Allow-Origin": "*",
104                "Access-Control-Allow-Methods": "GET"
105            },
106            body: JSON.stringify(
107                {"message": "500err"}
108            ),
109        });
110    })
111})