Jak psát testy na REST API

Jak spát hezké REST API, tak aby bylo dobře testovatelné a jak pak psát testy na takové API.

Transcript

1. Jak psát testy
   na REST API
   @ProchazkaFilip
   

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2. Co si povíme
   ● Jak vypadá naše api (Java + Spring)
   ● Out-of-Container vs End-to-End
   ● Design first?
   ● Spring MVC Test Framework
   ● Spring REST Docs
   ● Jaké testy psát
   

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3. Jak vypadá naše api (Java + Spring)
   Abych mohl testovat, musím mít dobře testovatelné api
   

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4. Jak vypadá naše api (Java + Spring): Testovatelné
   ● Typovost
   ○ Value Objecty
   ○ Mapování na VO vs na Entity
   ○ IN -> Scalar -> VO
   ○ OUT -> VO
   ● Striktnost
   ○ Přijímat pouze jeden jasně definovaný formát
   ■ Email není lowercase => 400
   ■ Špatný formát data => 400
   ● Automatizace
   

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5. Jak vypadá naše api (Java + Spring)
   ● Spring MVC
   ○ Custom argument resolvers
   ○ Custom error handling
   ■ Obecná struktura na chyby
   ● Hibernate Validator
   ● Jackson
   

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6. View Slide

7. @PostMapping("/users/{userId}/product-groups")
   public ResponseEntity createProductGroup(
   final AccessToken accessToken,
   final Pageable pageable,
   final ClientInfo clientInfo,
   @PathVariable
   @AssertUuid
   final String userId,
   @RequestBody
   @Valid
   final CreateProductGroupRequest createRequest
   )
   

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8. public static final class CreateProductGroupRequest {
   @NotNull
   @NotBlank
   private String name;
   @AssertEnumValue(value = CustomerSubscriptionSystemModuleSerializable.class)
   private String module;
   @AssertEnumValue(value = ProductGroupTypeSerializable.class)
   private String type;
   @Valid
   private CreateProductGroupRequest.ParentRequest parent;
   @Valid
   private CreateProductGroupRequest.TemplateRequest template;
   

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9. public ProductGroupType toProductGroupType()
   {
   return Optional.ofNullable(type)
   .map(ProductGroupTypeSerializable::forValue)
   .map(ProductGroupTypeSerializable::toGroupType)
   .orElse(null);
   }
   

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10. ProductGroupResult productGroup = productGroupFacade.createProductGroup(
    accessToken,
    UUID.fromString(userId),
    createRequest.getName(),
    createRequest.toProductGroupType(),
    createRequest.toSystemModule(),
    createRequest.toParentId(),
    createRequest.toTemplateId()
    );
    return new ResponseEntity<>(
    new WrappedProductGroupResponse(
    productGroupResponseFactory.getProductGroup(productGroup)
    ),
    HttpStatus.CREATED
    );
    

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11. public static final class ProductGroupResponse {
    private UUID id;
    private String name;
    private ProductGroupTypeSerializable type;
    private CustomerSubscriptionSystemModuleSerializable module;
    private ParentResponse parent;
    // ...
    public static final class ParentResponse {
    private UUID id;
    private String name;
    // ...
    }
    }
    

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12. try {
    // …
    } catch (AccessTokenDoesNotHaveAccessToUserException | UserNotFoundException e) {
    throw userResponseFactory.buildUserNotFound(e);
    } catch (ProductGroupParentNotFoundException e) {
    throw productGroupResponseFactory.buildProductGroupParentNotFound(e);
    } catch (ProductGroupTemplateNotFoundException e) {
    throw productGroupResponseFactory.buildProductGroupTemplateNotFound(e);
    } catch (CustomerDoesNotHaveSubscriptionForSystemModuleException e) {
    throw productGroupResponseFactory
    .buildCustomerDoesNotHaveSubscriptionForSystemModule(e);
    }
    

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13. public UnprocessableEntityException buildCustomerDoesNotHaveSubscriptionForSystemModule(
    final CustomerDoesNotHaveSubscriptionForSystemModuleException e
    )
    {
    Set availableModules = e.getAvailableModules().stream()
    .map(CustomerSubscriptionSystemModuleSerializable::fromSystemModule)
    .collect(Collectors.toSet());
    return UnprocessableEntityException.builder()
    .withCode(ErrorCode.PRODUCT_GROUP_CUSTOMER_DOES_NOT_HAVE_SUBSCRIPTION_FOR_SYSTEM_MODULE)
    .withTitle("Customer does not have subscription for the system module")
    .withDetails(String.format(
    "Available modules are: %s",
    availableModules.stream()
    .map(CustomerSubscriptionSystemModuleSerializable::getValue)
    .collect(Collectors.joining(", "))
    ))
    .addMeta("availableModules", availableModules)
    .build(e);
    }
    

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14. public enum ErrorCode
    {
    CUSTOMER_LOCKED("customer-locked"),
    INTERNAL_SERVER_ERROR("internal-server-error"),
    PRODUCT_NOT_FOUND("product-not-found"),
    USER_NOT_FOUND("user-not-found");
    private final String code;
    ErrorCode(final String code) { this.code = code; }
    @JsonValue
    public String getCode() { return code; }
    @Override
    public String toString() { return code; }
    }
    

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15. {
    "errors" : [ {
    "code" : "request-validation-error",
    "title" : "Invalid Request",
    "details" : "Unrecognizable query parameter",
    "source" : {
    "parameter" : "filter-wtf"
    }
    }, {
    "code" : "request-validation-error",
    "title" : "Invalid Request",
    "details" : "Parameter must be greater than or equal to 1",
    "source" : {
    "parameter" : "perPage"
    }
    }, {
    "code" : "request-validation-error",
    "title" : "Invalid Request",
    "details" : "Field must not be blank",
    "source" : {
    "pointer" : "/password"
    }
    } ]
    }
    

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16. Out-of-Container vs End-to-End
    (MockServer vs Full HTTP server)
    

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17. Out-of-Container vs End-to-End
    ● Whitebox vs Blackbox
    ● Asserts
    ○ Internal state of the API
    ● Mocking services
    ○ Locking
    ○ Faking responses from 3rd party
    ■ Payment gateway API
    

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18. Design first?
    

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19. Design first
    ● Tools
    ○ Blueprint, OpenAPI, ...
    ○ Dredd
    ● Contract testing
    ○ Není náhrada za integrační testy
    ● “Tužka a papír”
    ○ Načrtnu strukturu happy path
    ○ Vypíšu seznam (bussines) chybových stavů
    

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20. Spring MVC Tests
    

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21. Spring MVC Test Framework
    ● Integruje Spring s testovacími FW
    ● Zkratky, utility, …
    

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22. Spring MVC Tests (v podání Cogvio)
    ● Start PostgreSQL + ElasticSearch v Docker Containeru
    ● Schema
    ● Fixtures
    ○ Naplní PostgreSQL
    ○ Naplní ElasticSearch
    ● Snapshot databáze
    ○ CREATE DATABASE … WITH TEMPLATE …
    

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23. CreateProductGroupRequest createRequest = new CreateProductGroupRequest(
    "Foo", // name
    null, // module
    ProductGroupTypeSerializable.PRODUCT_LIST,
    null, // parent
    null // template
    );
    performRequest(
    post("/v1/users/{userId}/product-groups", userId)
    .content(toJson(createRequest))
    .with(accessToken(UserFixtures.bfuPepaAccessToken)))
    .andExpect(status().isCreated())
    .andExpect(content().contentType(MediaType.APPLICATION_JSON_UTF8))
    .andExpect(jsonPath("$.productGroup.name").value("Foo"))
    .andExpect(jsonPath("$.productGroup.productsCount").value(0))
    .andExpect(jsonPath("$.productGroup.parent").isEmpty());
    

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24. Mockito.doThrow(new ProductGroupLockedException(groupId, userId,
    new PersistenceException("mock")
    ))
    .when(productGroupRepository)
    .getProductGroupForUpdate(
    ArgumentMatchers.any(UUID.class),
    ArgumentMatchers.any(UUID.class)
    );
    performRequest(
    put("/v1/users/{userId}/product-groups/{groupId}", userId, groupId)
    .content(toJson(new UpdateProductGroupRequest("Maxitrol")))
    .with(accessToken(UserFixtures.bfuPepaAccessToken)))
    .andExpect(status().isConflict())
    .andExpect(content().contentType(MediaType.APPLICATION_JSON_UTF8));
    

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25. Spring REST Docs
    

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26. Spring REST Docs
    ● Spring MVC Test Framework
    ● Nahrává z testů
    ○ Reálnou komunikaci
    ○ Dokumentaci
    ○ Validační annotace
    ● Renderuje
    

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27. http-request.adoc
    [source,http,options="nowrap"]
    ----
    POST /v1/users/4482f319-dd3a-4a08-9d35-279c90041f6e/product-groups HTTP/1.1
    Content-Type: application/json;charset=UTF-8
    Accept: application/json
    Authorization: Bearer d4b084e5-66d3-40ff-b2b4-1dd2a8cdccd0
    {
    "name" : "Foo",
    "module" : null,
    "type" : "group",
    "parent" : null,
    "template" : null
    }
    ----
    

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28. http-response.adoc
    [source,http,options="nowrap"]
    ----
    HTTP/1.1 201 Created
    Content-Type: application/json;charset=UTF-8
    Content-Length: 537
    {
    "productGroup" : {
    "id" : "b511a54a-c7fe-4c5e-931e-0c7c80e3586c",
    "name" : "Foo",
    "type" : "group",
    "module" : null,
    "parent" : null,
    "productsCount" : 0
    }
    }
    ----
    

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29. document(pathParameters(
    guidParameter("userId", "Id of the relevant user"),
    parameterWithName(ProductGroupController.FILTER_PARENT_GROUP_PARAM)
    .description("Search in the relevant parent product group")
    ));
    

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30. path-parameters.adoc
    .Path parameters
    * `userId`: `9b4917db-0b88-4954-8e52-43c7e96c24ab` (`UUID`) - Id of the relevant user
    * `groupId`: `44a0decf-bd9c-4bd1-bc87-b7a5f1272d3d` (`UUID`) - Id of the requested products group
    

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31. index.adoc
    === GET /v1/users/{userId}/product-groups
    Outputs all the product groups of given user.
    include::{snippets}/product-group-controller-test/list-product-groups/1/path-parameters.adoc[]
    include::{snippets}/product-group-controller-test/list-product-groups/1/request-parameters.adoc[]
    ==== 200 Successful fetch
    include::{snippets}/product-group-controller-test/list-product-groups/1/http-request.adoc[]
    *Response*
    include::{snippets}/product-group-controller-test/list-product-groups/1/http-response.adoc[]
    

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32. View Slide

33. document(requestFields(
    payloadField("name", String.class, "Name of the product group",
    describeFieldConstraints(CreateProductGroupRequest.class, "name")),
    payloadField("type", String.class, "Type of the group",
    describeFieldConstraints(CreateProductGroupRequest.class, "type")),
    payloadField("module", String.class, "System module for the group",
    describeFieldConstraints(CreateProductGroupRequest.class, "module")),
    payloadField("parent", Object.class, "Parent group",
    describeFieldConstraints(CreateProductGroupRequest.class, "parent")),
    payloadField("template", Object.class, "Template group (for copying)",
    describeFieldConstraints(CreateProductGroupRequest.class, "template")),
    payloadField("template.id", UUID.class, "Id of template group",
    describeFieldConstraints(CreateProductGroupRequest.ParentRequest.class, "id"))
    ));
    

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34. request-fields.adoc
    .Request body fields
    |===
    |Path|Type|Description|Constraints
    |`name`
    |String
    |Name of the product group
    |Must not be blank. Must not be null.
    |`type`
    |String
    |Type of the group
    |Value must be one of [`product-list`, `group`].
    

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35. index.adoc
    === POST /v1/users/{userId}/product-groups
    Creates a new product group.
    include::{snippets}/product-group-controller-test/create-product-group/1/path-parameters.adoc[]
    include::{snippets}/product-group-controller-test/create-product-group/1/request-fields.adoc[]
    ==== 201 Successful create
    include::{snippets}/product-group-controller-test/create-product-group/1/http-request.adoc[]
    *Response*
    include::{snippets}/product-group-controller-test/create-product-group/1/http-response.adoc[]
    

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36. View Slide

37. Jaké testy psát
    

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38. Jaké testy psát
    ● Happy path
    ● All the errors
    ● Some edge cases?
    

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39. @ProchazkaFilip
    

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