Expose Expense Categories query API

server/src/main/java/io/myfinbox/expense/adapter/web/ExpenseCategoryController.java

@@ -1,5 +1,6 @@
 package io.myfinbox.expense.adapter.web;
 
+import io.myfinbox.expense.application.CategoryQuery;
 import io.myfinbox.expense.application.CategoryService;
 import io.myfinbox.expense.domain.Category;
 import io.myfinbox.rest.ExpenseCategoryResource;
@@ -21,6 +22,7 @@
 final class ExpenseCategoryController implements ExpensesCategoryApi {
 
     private final CategoryService categoryService;
+    private final CategoryQuery categoryQuery;
     private final ApiFailureHandler apiFailureHandler;
 
     @PostMapping(consumes = APPLICATION_JSON_VALUE, produces = APPLICATION_JSON_VALUE)
@@ -43,6 +45,13 @@ public ResponseEntity<?> delete(@PathVariable UUID categoryId) {
                 .fold(apiFailureHandler::handle, ok -> noContent().build());
     }
 
+    @GetMapping
+    public ResponseEntity<?> list(@RequestParam(value = "accountId") UUID accountId) {
+        return ok(categoryQuery.search(accountId).stream()
+                .map(this::toResource)
+                .toList());
+    }
+
     private ExpenseCategoryResource toResource(Category category) {
         return new ExpenseCategoryResource()
                 .categoryId(category.getId().id())

server/src/main/java/io/myfinbox/expense/adapter/web/ExpensesCategoryApi.java

@@ -5,6 +5,7 @@
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
 import io.swagger.v3.oas.annotations.headers.Header;
+import io.swagger.v3.oas.annotations.media.ArraySchema;
 import io.swagger.v3.oas.annotations.media.Content;
 import io.swagger.v3.oas.annotations.media.Schema;
 import io.swagger.v3.oas.annotations.parameters.RequestBody;
@@ -17,6 +18,7 @@
 import java.util.UUID;
 
 import static io.swagger.v3.oas.annotations.enums.ParameterIn.PATH;
+import static io.swagger.v3.oas.annotations.enums.ParameterIn.QUERY;
 import static org.springframework.http.HttpHeaders.LOCATION;
 import static org.springframework.http.MediaType.APPLICATION_JSON_VALUE;
 
@@ -81,4 +83,18 @@ ResponseEntity<?> update(@Parameter(in = PATH, description = "CategoryId to be u
                     content = @Content(mediaType = APPLICATION_JSON_VALUE, schema = @Schema(implementation = ApiErrorResponse.class)))
     })
     ResponseEntity<?> delete(@Parameter(in = PATH, description = "CategoryId to be deleted", required = true) UUID categoryId);
+
+    @Operation(summary = "Query a list of expense categories for a specified account in the MyFinBox",
+            description = "Query a list of expense categories for a specified account in the MyFinBox",
+            security = {@SecurityRequirement(name = "openId")},
+            tags = {TAG})
+    @ApiResponses(value = {
+            @ApiResponse(responseCode = "200", description = "Successful Operation",
+                    content = @Content(mediaType = "application/json", array = @ArraySchema(schema = @Schema(implementation = ExpenseCategoryResource.class)))),
+            @ApiResponse(responseCode = "400", description = "Malformed JSON or Type Mismatch Failure",
+                    content = @Content(mediaType = APPLICATION_JSON_VALUE, schema = @Schema(implementation = ApiErrorResponse.class))),
+            @ApiResponse(responseCode = "500", description = "Internal Server Error",
+                    content = @Content(mediaType = APPLICATION_JSON_VALUE, schema = @Schema(implementation = ApiErrorResponse.class)))
+    })
+    ResponseEntity<?> list(@Parameter(in = QUERY, description = "Account to be used for selecting categories", required = true) UUID accountId);
 }

server/src/main/java/io/myfinbox/expense/application/CategoryQuery.java

@@ -0,0 +1,21 @@
+package io.myfinbox.expense.application;
+
+import io.myfinbox.expense.domain.Category;
+
+import java.util.List;
+import java.util.UUID;
+
+/**
+ * Interface for querying category information.
+ */
+public interface CategoryQuery {
+
+    /**
+     * Searches for categories associated with a specific account.
+     *
+     * @param accountId the unique identifier of the account to search categories for
+     * @return a list of {@link Category} objects associated with the specified account
+     */
+    List<Category> search(UUID accountId);
+}
+

server/src/main/java/io/myfinbox/expense/application/CategoryQueryService.java

@@ -0,0 +1,31 @@
+package io.myfinbox.expense.application;
+
+import io.myfinbox.expense.domain.AccountIdentifier;
+import io.myfinbox.expense.domain.Categories;
+import io.myfinbox.expense.domain.Category;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+import java.util.UUID;
+
+import static java.util.Collections.emptyList;
+import static java.util.Objects.isNull;
+
+@Service
+@RequiredArgsConstructor
+@Transactional(readOnly = true)
+class CategoryQueryService implements CategoryQuery {
+
+    private final Categories categories;
+
+    @Override
+    public List<Category> search(UUID accountId) {
+        if (isNull(accountId)) {
+            return emptyList();
+        }
+
+        return categories.findByAccount(new AccountIdentifier(accountId));
+    }
+}

server/src/test/groovy/io/myfinbox/expense/DataSamples.groovy

@@ -122,4 +122,8 @@ class DataSamples {
     static newValidExpenseCategoryResource(map = [:]) {
         JsonOutput.toJson(EXPENSE_CATEGORY_RESOURCE + map) as String
     }
+
+    static newValidExpenseCategoryResourceList() {
+        JsonOutput.toJson([EXPENSE_CATEGORY_RESOURCE, EXPENSE_CATEGORY_RESOURCE + [categoryId: categoryId2, name: 'Other']]) as String
+    }
 }

server/src/test/groovy/io/myfinbox/expense/adapter/web/ExpenseCategoryControllerSpec.groovy

@@ -11,15 +11,18 @@ import org.springframework.boot.test.web.client.TestRestTemplate
 import org.springframework.core.io.ClassPathResource
 import org.springframework.http.HttpEntity
 import org.springframework.http.HttpHeaders
+import org.springframework.http.HttpMethod
 import org.springframework.http.ResponseEntity
 import org.springframework.jdbc.core.JdbcTemplate
 import org.springframework.test.context.TestPropertySource
 import org.springframework.test.context.jdbc.Sql
 import org.springframework.test.jdbc.JdbcTestUtils
+import org.springframework.web.util.UriComponentsBuilder
 import spock.lang.Specification
 import spock.lang.Tag
 
 import static io.myfinbox.expense.DataSamples.newValidExpenseCategoryResource
+import static io.myfinbox.expense.DataSamples.newValidExpenseCategoryResourceList
 import static org.skyscreamer.jsonassert.JSONCompareMode.LENIENT
 import static org.springframework.boot.test.context.SpringBootTest.WebEnvironment.RANDOM_PORT
 import static org.springframework.http.HttpMethod.DELETE
@@ -123,6 +126,18 @@ class ExpenseCategoryControllerSpec extends Specification {
         JSONAssert.assertEquals(expectDeleteConflictFailure(), response.getBody(), LENIENT)
     }
 
+    @Sql('/expense/web/expensecategory-create.sql')
+    def "should get a list with two expense category"() {
+        when: 'list expense category'
+        def response = getExpenses(UUID.fromString(DataSamples.accountId))
+
+        then: 'response status is OK'
+        assert response.getStatusCode() == OK
+
+        and: 'a list of two expense is present'
+        JSONAssert.assertEquals(newValidExpenseCategoryResourceList(), response.getBody(), LENIENT)
+    }
+
     private postExpenseCategory(String request) {
         restTemplate.postForEntity('/v1/expenses/category', entityRequest(request), String.class)
     }
@@ -145,6 +160,20 @@ class ExpenseCategoryControllerSpec extends Specification {
         )
     }
 
+    def getExpenses(UUID accountId) {
+        def uri = UriComponentsBuilder.fromUriString("${restTemplate.getRootUri()}/v1/expenses/category")
+                .queryParam("accountId", accountId)
+                .build()
+                .toUri()
+
+        restTemplate.exchange(
+                uri,
+                HttpMethod.GET,
+                null,
+                String.class
+        )
+    }
+
     def entityRequest(String req) {
         var headers = new HttpHeaders()
         headers.setContentType(APPLICATION_JSON)

server/src/test/groovy/io/myfinbox/expense/application/CategoryQueryServiceSpec.groovy

@@ -0,0 +1,53 @@
+package io.myfinbox.expense.application
+
+import io.myfinbox.expense.domain.AccountIdentifier
+import io.myfinbox.expense.domain.Categories
+import spock.lang.Specification
+import spock.lang.Tag
+
+import static io.myfinbox.expense.DataSamples.newSampleCategory
+
+@Tag("unit")
+class CategoryQueryServiceSpec extends Specification {
+
+    Categories categories
+    CategoryQueryService service
+
+    def setup() {
+        categories = Mock()
+        service = new CategoryQueryService(categories)
+    }
+
+    def "should get empty list when categories for provided account id not found"() {
+        setup: 'mock the repository to return an empty list for any account identifier'
+        1 * categories.findByAccount(_ as AccountIdentifier) >> []
+
+        when: 'searching for categories with a non-exiting account ID'
+        def categoryList = service.search(UUID.randomUUID())
+
+        then: 'the result should be an empty list'
+        assert categoryList.isEmpty()
+    }
+
+    def "should get empty list when account id is null"() {
+        when: 'searching for categories with a null account ID'
+        def categoryList = service.search(null)
+
+        then: 'the result should be an empty list'
+        assert categoryList.isEmpty()
+
+        and: 'the repository should not be queried'
+        0 * categories.findByAccount(_ as AccountIdentifier)
+    }
+
+    def "should get a list of categories"() {
+        setup: 'mock the repository to return a list with a sample category for any account identifier'
+        1 * categories.findByAccount(_ as AccountIdentifier) >> [newSampleCategory()]
+
+        when: 'Searching for categories with a random account ID'
+        def categoryList = service.search(UUID.randomUUID())
+
+        then: 'the result should be a list with one category'
+        assert categoryList.size() == 1
+    }
+}

server/src/test/resources/expense/web/expensecategory-create.sql

@@ -1,9 +1,12 @@
 INSERT INTO server.expense_category (id,
                                      account_id,
+                                     creation_timestamp,
                                      name)
 VALUES ('3b257779-a5db-4e87-9365-72c6f8d4977d',
         'e2709aa2-7907-4f78-98b6-0f36a0c1b5ca',
+        '2024-03-23T10:00:04.224870Z',
         'Bills'),
        ('e2709aa2-7907-4f78-98b6-0f36a0c1b5ca',
         'e2709aa2-7907-4f78-98b6-0f36a0c1b5ca',
+        '2024-03-23T10:00:04.224870Z',
         'Other');