Merge branch 'feature/page-crud' into 'master'

CRUD for pages and layouts.

Closes #33

See merge request theappsmith/internal-tools-server!14

app/server/src/main/java/com/appsmith/server/configurations/ClientUserRepository.java

@@ -7,7 +7,6 @@ import com.appsmith.server.exceptions.AppsmithError;
 import com.appsmith.server.exceptions.AppsmithException;
 import com.appsmith.server.services.OrganizationService;
 import com.appsmith.server.services.UserService;
-import org.springframework.context.annotation.Configuration;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.oauth2.client.OAuth2AuthorizedClient;
 import org.springframework.security.oauth2.client.web.server.ServerOAuth2AuthorizedClientRepository;
@@ -84,10 +83,10 @@ public class ClientUserRepository implements ServerOAuth2AuthorizedClientReposit
         // Check if the list of configured custom domains match the authenticated principal.
         // This is to provide more control over which accounts can be used to access the application.
         // TODO: This is not a good way to do this. Ideally, we should pass "hd=example.com" to OAuth2 provider to list relevant accounts only
-        if(!commonConfig.getAllowedDomains().isEmpty()) {
+        if (!commonConfig.getAllowedDomains().isEmpty()) {
             DefaultOidcUser userPrincipal = (DefaultOidcUser) principal.getPrincipal();
             String domain = (String) userPrincipal.getAttributes().getOrDefault("hd", "");
-            if(!commonConfig.getAllowedDomains().contains(domain)) {
+            if (!commonConfig.getAllowedDomains().contains(domain)) {
                 return Mono.error(new AppsmithException(AppsmithError.UNAUTHORIZED_DOMAIN));
             }
         }

app/server/src/main/java/com/appsmith/server/constants/FieldName.java

@@ -4,4 +4,7 @@ public class FieldName {
     public static String ORGANIZATION = "organization";
     public static String ID = "id";
     public static String NAME = "name";
+    public static String PAGEID = "pageId";
+    public static String LAYOUTID = "layoutId";
+    public static String APPLICATIONID = "applicationId";
 }

app/server/src/main/java/com/appsmith/server/constants/Url.java

@@ -13,4 +13,5 @@ public interface Url {
     String ACTION_URL = BASE_URL + VERSION + "/actions";
     String USER_URL = BASE_URL + VERSION + "/users";
     String APPLICATION_URL = BASE_URL + VERSION + "/applications";
+    String PAGE_URL = BASE_URL + VERSION + "/pages";
 }

app/server/src/main/java/com/appsmith/server/controllers/LayoutController.java

@@ -2,17 +2,48 @@ package com.appsmith.server.controllers;
 
 import com.appsmith.server.constants.Url;
 import com.appsmith.server.domains.Layout;
+import com.appsmith.server.dtos.ResponseDto;
 import com.appsmith.server.services.LayoutService;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Mono;
+
+import javax.validation.Valid;
 
 @RestController
 @RequestMapping(Url.LAYOUT_URL)
-public class LayoutController extends BaseController<LayoutService, Layout, String> {
+public class LayoutController {
+
+    private final LayoutService service;
 
     @Autowired
-    public LayoutController(LayoutService service) {
-        super(service);
+    public LayoutController(LayoutService layoutService) {
+        this.service = layoutService;
     }
+
+    @PostMapping("/pages/{pageId}")
+    public Mono<ResponseDto<Layout>> createLayout(@PathVariable String pageId, @Valid @RequestBody Layout layout) {
+        return service.createLayout(pageId, layout)
+                .map(created -> new ResponseDto<>(HttpStatus.CREATED.value(), created, null));
+    }
+
+    @GetMapping("/{layoutId}/pages/{pageId}")
+    public Mono<ResponseDto<Layout>> getLayout(@PathVariable String pageId, @PathVariable String layoutId) {
+        return service.getLayout(pageId, layoutId)
+                .map(created -> new ResponseDto<>(HttpStatus.CREATED.value(), created, null));
+    }
+
+    @PutMapping("/{layoutId}/pages/{pageId}")
+    public Mono<ResponseDto<Layout>> updateLayout(@PathVariable String pageId, @PathVariable String layoutId, @RequestBody Layout layout) {
+        return service.updateLayout(pageId, layoutId, layout)
+                .map(created -> new ResponseDto<>(HttpStatus.CREATED.value(), created, null));
+    }
+
 }

app/server/src/main/java/com/appsmith/server/controllers/PageController.java

@@ -0,0 +1,21 @@
+package com.appsmith.server.controllers;
+
+import com.appsmith.server.constants.Url;
+import com.appsmith.server.domains.Page;
+import com.appsmith.server.services.PageService;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping(Url.PAGE_URL)
+@Slf4j
+public class PageController extends BaseController<PageService, Page, String> {
+
+    @Autowired
+    public PageController(PageService service) {
+        super(service);
+    }
+
+}

app/server/src/main/java/com/appsmith/server/domains/Page.java

@@ -6,6 +6,7 @@ import lombok.Setter;
 import lombok.ToString;
 import org.springframework.data.mongodb.core.mapping.Document;
 
+import javax.validation.constraints.NotNull;
 import java.util.List;
 
 @Getter
@@ -16,6 +17,7 @@ import java.util.List;
 public class Page extends BaseDomain {
     String name;
 
+    @NotNull
     String applicationId;
 
     List<Layout> layouts;

app/server/src/main/java/com/appsmith/server/exceptions/AppsmithError.java

@@ -12,6 +12,7 @@ public enum AppsmithError {
     PLUGIN_NOT_INSTALLED(400, 4001, "Plugin {0} not installed"),
     PLUGIN_ID_NOT_GIVEN(400, 4002, "Missing plugin id. Please input correct plugin id"),
     RESOURCE_ID_NOT_GIVEN(400, 4003, "Missing resource id. Please input correct resource id"),
+    PAGE_DOESNT_BELONG_TO_USER_ORGANIZATION(400, 4006, "Page {0} does not belong to the current user {1} organization."),
     UNAUTHORIZED_DOMAIN(401, 4001, "Invalid email domain provided. Please sign in with a valid work email ID"),
     INTERNAL_SERVER_ERROR(500, 5000, "Internal server error while processing request");
 

app/server/src/main/java/com/appsmith/server/repositories/ApplicationRepository.java

@@ -2,7 +2,16 @@ package com.appsmith.server.repositories;
 
 import com.appsmith.server.domains.Application;
 import org.springframework.stereotype.Repository;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 
 @Repository
 public interface ApplicationRepository extends BaseRepository<Application, String> {
+    Flux<Application> findByOrganizationId(String orgId);
+
+    Mono<Application> findByIdAndOrganizationId(String id, String orgId);
+
+    Mono<Application> findById(String id);
+
+    Mono<Application> findByName(String name);
 }

app/server/src/main/java/com/appsmith/server/repositories/PageRepository.java

@@ -0,0 +1,14 @@
+package com.appsmith.server.repositories;
+
+import com.appsmith.server.domains.Page;
+import org.springframework.stereotype.Repository;
+import reactor.core.publisher.Mono;
+
+@Repository
+public interface PageRepository extends BaseRepository<Page, String> {
+    Mono<Page> findByIdAndLayoutsId(String id, String layoutId);
+
+    Mono<Page> findByName(String name);
+
+    Mono<Void> deleteAll();
+}

app/server/src/main/java/com/appsmith/server/services/ApplicationService.java

@@ -1,6 +1,12 @@
 package com.appsmith.server.services;
 
 import com.appsmith.server.domains.Application;
+import reactor.core.publisher.Mono;
 
 public interface ApplicationService extends CrudService<Application, String> {
+    Mono<Application> findById(String id);
+
+    Mono<Application> findByIdAndOrganizationId(String id, String organizationId);
+
+    Mono<Application> findByName(String name);
 }

app/server/src/main/java/com/appsmith/server/services/ApplicationServiceImpl.java

@@ -1,18 +1,23 @@
 package com.appsmith.server.services;
 
+import com.appsmith.server.constants.FieldName;
 import com.appsmith.server.domains.Application;
 import com.appsmith.server.domains.User;
+import com.appsmith.server.exceptions.AppsmithError;
+import com.appsmith.server.exceptions.AppsmithException;
 import com.appsmith.server.repositories.ApplicationRepository;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.mongodb.core.ReactiveMongoTemplate;
 import org.springframework.data.mongodb.core.convert.MongoConverter;
 import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 import reactor.core.scheduler.Scheduler;
 
 import javax.validation.Validator;
 
+
 @Slf4j
 @Service
 public class ApplicationServiceImpl extends BaseService<ApplicationRepository, Application, String> implements ApplicationService {
@@ -27,6 +32,10 @@ public class ApplicationServiceImpl extends BaseService<ApplicationRepository, A
 
     @Override
     public Mono<Application> create(Application application) {
+        if (application.getName() == null) {
+            return Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.NAME));
+        }
+
         Mono<User> userMono = userService.getCurrentUser();
 
         return userMono
@@ -37,4 +46,42 @@ public class ApplicationServiceImpl extends BaseService<ApplicationRepository, A
                 })
                 .flatMap(repository::save);
     }
+
+    @Override
+    public Flux<Application> get() {
+        Mono<User> userMono = userService.getCurrentUser();
+
+        return userMono
+                .map(user -> user.getOrganizationId())
+                .flatMapMany(orgId -> repository.findByOrganizationId(orgId));
+    }
+
+    @Override
+    public Mono<Application> getById(String id) {
+        if (id == null) {
+            return Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.ID));
+        }
+
+        Mono<User> userMono = userService.getCurrentUser();
+
+        return userMono
+                .map(user -> user.getOrganizationId())
+                .flatMap(orgId -> repository.findByIdAndOrganizationId(id, orgId))
+                .switchIfEmpty(Mono.error(new AppsmithException(AppsmithError.NO_RESOURCE_FOUND, "resource", id)));
+    }
+
+    @Override
+    public Mono<Application> findById(String id) {
+        return repository.findById(id);
+    }
+
+    @Override
+    public Mono<Application> findByIdAndOrganizationId(String id, String organizationId) {
+        return repository.findByIdAndOrganizationId(id, organizationId);
+    }
+
+    @Override
+    public Mono<Application> findByName(String name) {
+        return repository.findByName(name);
+    }
 }

app/server/src/main/java/com/appsmith/server/services/LayoutService.java

@@ -1,6 +1,12 @@
 package com.appsmith.server.services;
 
 import com.appsmith.server.domains.Layout;
+import reactor.core.publisher.Mono;
 
-public interface LayoutService extends CrudService<Layout, String> {
+public interface LayoutService {
+    Mono<Layout> createLayout(String pageId, Layout layout);
+
+    Mono<Layout> getLayout(String pageId, String layoutId);
+
+    Mono<Layout> updateLayout(String pageId, String layoutId, Layout layout);
 }

app/server/src/main/java/com/appsmith/server/services/LayoutServiceImpl.java

@@ -1,26 +1,100 @@
 package com.appsmith.server.services;
 
+import com.appsmith.server.constants.FieldName;
 import com.appsmith.server.domains.Layout;
-import com.appsmith.server.repositories.LayoutRepository;
+import com.appsmith.server.domains.Page;
+import com.appsmith.server.exceptions.AppsmithError;
+import com.appsmith.server.exceptions.AppsmithException;
 import lombok.extern.slf4j.Slf4j;
+import org.bson.types.ObjectId;
+import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.data.mongodb.core.ReactiveMongoTemplate;
-import org.springframework.data.mongodb.core.convert.MongoConverter;
 import org.springframework.stereotype.Service;
-import reactor.core.scheduler.Scheduler;
+import reactor.core.publisher.Mono;
 
-import javax.validation.Validator;
+import java.util.ArrayList;
+import java.util.List;
 
 @Slf4j
 @Service
-public class LayoutServiceImpl extends BaseService<LayoutRepository, Layout, String> implements LayoutService {
+public class LayoutServiceImpl implements LayoutService {
+
+    private final PageService pageService;
 
     @Autowired
-    public LayoutServiceImpl(Scheduler scheduler,
-                             Validator validator,
-                             MongoConverter mongoConverter,
-                             ReactiveMongoTemplate reactiveMongoTemplate,
-                             LayoutRepository repository) {
-        super(scheduler, validator, mongoConverter, reactiveMongoTemplate, repository);
+    public LayoutServiceImpl(PageService pageService) {
+        this.pageService = pageService;
+    }
+
+    @Override
+    public Mono<Layout> createLayout(String pageId, Layout layout) {
+        if (pageId == null) {
+            return Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.PAGEID));
+        }
+
+        Mono<Page> pageMono = pageService
+                .findById(pageId)
+                .switchIfEmpty(Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.PAGEID)));
+
+        return pageMono
+                .map(page -> {
+                    List<Layout> layoutList = page.getLayouts();
+                    if (layoutList == null) {
+                        //no layouts exist for this page
+                        layoutList = new ArrayList<Layout>();
+                    }
+                    //Adding an Id to the layout to ensure that a layout can be referred to by its ID as well.
+                    layout.setId(new ObjectId().toString());
+                    layoutList.add(layout);
+                    page.setLayouts(layoutList);
+                    return page;
+                })
+                .flatMap(pageService::save)
+                .then(Mono.just(layout));
+    }
+
+    @Override
+    public Mono<Layout> getLayout(String pageId, String layoutId) {
+        return pageService.findByIdAndLayoutsId(pageId, layoutId)
+                .switchIfEmpty(Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.PAGEID + " or " + FieldName.LAYOUTID)))
+                .flatMap(pageService::doesPageIdBelongToCurrentUserOrganization)
+                //The pageId given is correct and belongs to the current user's organization.
+                .map(page -> {
+                    List<Layout> layoutList = page.getLayouts();
+                    //Because the findByIdAndLayoutsId call returned non-empty result, we are guaranteed to find the layoutId here.
+                    return layoutList.stream().filter(layout -> layout.getId().equals(layoutId)).findFirst().get();
+                });
+    }
+
+    @Override
+    public Mono<Layout> updateLayout(String pageId, String layoutId, Layout layout) {
+        return pageService.findByIdAndLayoutsId(pageId, layoutId)
+                .switchIfEmpty(Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.PAGEID + " or " + FieldName.LAYOUTID)))
+                .flatMap(pageService::doesPageIdBelongToCurrentUserOrganization)
+                //The pageId given is correct and belongs to the current user's organization.
+                .map(page -> {
+                    List<Layout> layoutList = page.getLayouts();
+                    //Because the findByIdAndLayoutsId call returned non-empty result, we are guaranteed to find the layoutId here.
+                    for (Layout storedLayout : layoutList) {
+                        if (storedLayout.getId().equals(layoutId)) {
+                            BeanUtils.copyProperties(layout, storedLayout);
+                            storedLayout.setId(layoutId);
+                            break;
+                        }
+                    }
+                    page.setLayouts(layoutList);
+                    return page;
+                })
+                .flatMap(pageService::save)
+                .flatMap(page -> {
+                    List<Layout> layoutList = page.getLayouts();
+                    for (Layout storedLayout : layoutList) {
+                        if (storedLayout.getId().equals(layoutId)) {
+                            return Mono.just(storedLayout);
+                        }
+                    }
+                    return Mono.empty();
+                });
     }
 }
+

app/server/src/main/java/com/appsmith/server/services/OrganizationServiceImpl.java

@@ -56,7 +56,6 @@ public class OrganizationServiceImpl extends BaseService<OrganizationRepository,
             return Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.ORGANIZATION));
         }
 
-        log.debug("Going to create the organization {}", organization.getName());
         return Mono.just(organization)
                 .flatMap(this::validateObject)
                 //transform the organization data to embed setting object in each object in organizationSetting list.

app/server/src/main/java/com/appsmith/server/services/PageService.java

@@ -0,0 +1,19 @@
+package com.appsmith.server.services;
+
+import com.appsmith.server.domains.Page;
+import reactor.core.publisher.Mono;
+
+public interface PageService extends CrudService<Page, String> {
+
+    Mono<Page> findById(String pageId);
+
+    Mono<Page> save(Page page);
+
+    Mono<Page> findByIdAndLayoutsId(String pageId, String layoutId);
+
+    Mono<Page> doesPageIdBelongToCurrentUserOrganization(Page page);
+
+    Mono<Page> findByName(String name);
+
+    Mono<Void> deleteAll();
+}

app/server/src/main/java/com/appsmith/server/services/PageServiceImpl.java

@@ -0,0 +1,104 @@
+package com.appsmith.server.services;
+
+import com.appsmith.server.constants.FieldName;
+import com.appsmith.server.domains.Layout;
+import com.appsmith.server.domains.Page;
+import com.appsmith.server.domains.User;
+import com.appsmith.server.exceptions.AppsmithError;
+import com.appsmith.server.exceptions.AppsmithException;
+import com.appsmith.server.repositories.PageRepository;
+import lombok.extern.slf4j.Slf4j;
+import org.bson.types.ObjectId;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.mongodb.core.ReactiveMongoTemplate;
+import org.springframework.data.mongodb.core.convert.MongoConverter;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Mono;
+import reactor.core.scheduler.Scheduler;
+
+import javax.validation.Validator;
+import java.util.ArrayList;
+import java.util.List;
+
+@Service
+@Slf4j
+public class PageServiceImpl extends BaseService<PageRepository, Page, String> implements PageService {
+
+    private final UserService userService;
+    private final ApplicationService applicationService;
+
+    @Autowired
+    public PageServiceImpl(Scheduler scheduler, Validator validator, MongoConverter mongoConverter, ReactiveMongoTemplate reactiveMongoTemplate, PageRepository repository, UserService userService, ApplicationService applicationService) {
+        super(scheduler, validator, mongoConverter, reactiveMongoTemplate, repository);
+        this.userService = userService;
+        this.applicationService = applicationService;
+    }
+
+    @Override
+    public Mono<Page> create(Page page) {
+        if (page.getId() != null) {
+            return Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.ID));
+        } else if (page.getName() == null) {
+            return Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.NAME));
+        } else if (page.getApplicationId() == null) {
+            return Mono.error(new AppsmithException(AppsmithError.INVALID_PARAMETER, FieldName.APPLICATIONID));
+        }
+        List<Layout> layoutList = page.getLayouts();
+        if (layoutList == null) {
+            layoutList = new ArrayList<>();
+        }
+        if (layoutList.isEmpty()) {
+            layoutList.add(createDefaultLayout());
+            page.setLayouts(layoutList);
+        }
+        return repository.save(page);
+    }
+
+
+    @Override
+    public Mono<Page> findById(String pageId) {
+        return repository.findById(pageId);
+    }
+
+    @Override
+    public Mono<Page> save(Page page) {
+        return repository.save(page);
+    }
+
+    @Override
+    public Mono<Page> findByIdAndLayoutsId(String pageId, String layoutId) {
+        return repository.findByIdAndLayoutsId(pageId, layoutId);
+    }
+
+    @Override
+    public Mono<Page> doesPageIdBelongToCurrentUserOrganization(Page page) {
+        Mono<User> userMono = userService.getCurrentUser();
+        final String[] username = {null};
+
+        return userMono
+                .map(user -> {
+                    username[0] = user.getEmail();
+                    return user;
+                })
+                .flatMap(user -> applicationService.findByIdAndOrganizationId(page.getApplicationId(), user.getOrganizationId()))
+                .switchIfEmpty(Mono.error(new AppsmithException(AppsmithError.PAGE_DOESNT_BELONG_TO_USER_ORGANIZATION, page.getId(), username[0])))
+                //If mono transmits, then application id belongs to the current user's organization. Return page.
+                .then(Mono.just(page));
+    }
+
+    @Override
+    public Mono<Page> findByName(String name) {
+        return repository.findByName(name);
+    }
+
+    private Layout createDefaultLayout() {
+        Layout layout = new Layout();
+        layout.setId(new ObjectId().toString());
+        return layout;
+    }
+
+    @Override
+    public Mono<Void> deleteAll() {
+        return repository.deleteAll();
+    }
+}

app/server/src/test/java/com/appsmith/server/services/ApplicationServiceTest.java

@@ -0,0 +1,120 @@
+package com.appsmith.server.services;
+
+import com.appsmith.server.constants.FieldName;
+import com.appsmith.server.domains.Application;
+import com.appsmith.server.exceptions.AppsmithError;
+import com.appsmith.server.exceptions.AppsmithException;
+import lombok.extern.slf4j.Slf4j;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.security.test.context.support.WithMockUser;
+import org.springframework.test.context.junit4.SpringRunner;
+import reactor.core.publisher.Mono;
+import reactor.test.StepVerifier;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+@Slf4j
+public class ApplicationServiceTest {
+
+    @Autowired
+    ApplicationService applicationService;
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createApplicationWithNullName() {
+        Application application = new Application();
+        Mono<Application> applicationMono = Mono.just(application)
+                .flatMap(applicationService::create);
+        StepVerifier
+                .create(applicationMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                        throwable.getMessage().equals(AppsmithError.INVALID_PARAMETER.getMessage(FieldName.NAME)))
+                .verify();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createValidApplication() {
+        Application testApplication = new Application();
+        testApplication.setName("ApplicationServiceTest TestApp");
+        Mono<Application> applicationMono = applicationService.create(testApplication);
+
+        StepVerifier
+                .create(applicationMono)
+                .assertNext(application -> {
+                    assertThat(application).isNotNull();
+                    assertThat(application.getId()).isNotNull();
+                    assertThat(application.getName().equals("ApplicationServiceTest TestApp"));
+                })
+                .verifyComplete();
+    }
+
+    /* Tests for Get Application Flow */
+
+    @Test
+    public void getApplicationInvalidId() {
+        Mono<Application> applicationMono = applicationService.getById("random-id");
+        StepVerifier.create(applicationMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                        throwable.getMessage().equals(AppsmithError.NO_RESOURCE_FOUND.getMessage("resource", "random-id")))
+                .verify();
+    }
+
+    @Test
+    public void getApplicationNullId() {
+        Mono<Application> applicationMono = applicationService.getById(null);
+        StepVerifier.create(applicationMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                        throwable.getMessage().equals(AppsmithError.INVALID_PARAMETER.getMessage(FieldName.ID)))
+                .verify();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void validGetApplicationByName() {
+        Application application = new Application();
+        application.setName("validGetApplicationByName-Test");
+        Mono<Application> createApplication = applicationService.create(application);
+        Mono<Application> getApplication = createApplication.flatMap(t -> applicationService.getById(t.getId()));
+        StepVerifier.create(getApplication)
+                .assertNext(t -> {
+                    assertThat(t).isNotNull();
+                    assertThat(t.getId()).isNotNull();
+                    assertThat(t.getName()).isEqualTo("validGetApplicationByName-Test");
+                })
+                .verifyComplete();
+    }
+
+    /* Tests for Update Application Flow */
+    @Test
+    @WithMockUser(username = "api_user")
+    public void validUpdateApplication() {
+        Application application = new Application();
+        application.setName("validUpdateApplication-Test");
+
+        Mono<Application> createApplication =
+                applicationService
+                        .create(application);
+        Mono<Application> updateApplication = createApplication
+                .map(t -> {
+                    t.setName("NewValidUpdateApplication-Test");
+                    return t;
+                })
+                .flatMap(t -> applicationService.update(t.getId(), t))
+                .flatMap(t -> applicationService.getById(t.getId()));
+
+        StepVerifier.create(updateApplication)
+                .assertNext(t -> {
+                    assertThat(t).isNotNull();
+                    assertThat(t.getId()).isNotNull();
+                    assertThat(t.getName()).isEqualTo("NewValidUpdateApplication-Test");
+                })
+                .verifyComplete();
+    }
+    
+}

app/server/src/test/java/com/appsmith/server/services/LayoutServiceTest.java

@@ -0,0 +1,194 @@
+package com.appsmith.server.services;
+
+import com.appsmith.server.constants.FieldName;
+import com.appsmith.server.domains.Application;
+import com.appsmith.server.domains.Layout;
+import com.appsmith.server.domains.Page;
+import com.appsmith.server.exceptions.AppsmithError;
+import com.appsmith.server.exceptions.AppsmithException;
+import lombok.extern.slf4j.Slf4j;
+import net.minidev.json.JSONObject;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.security.test.context.support.WithMockUser;
+import org.springframework.test.context.junit4.SpringRunner;
+import reactor.core.publisher.Mono;
+import reactor.test.StepVerifier;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+@Slf4j
+public class LayoutServiceTest {
+    @Autowired
+    LayoutService layoutService;
+
+    @Autowired
+    ApplicationService applicationService;
+
+    @Autowired
+    PageService pageService;
+
+    Mono<Layout> layoutMono;
+
+    Mono<Application> applicationMono;
+
+    @Before
+    @WithMockUser(username = "api_user")
+    public void setup() {
+
+        Application testApplication = new Application();
+        testApplication.setName("LayoutServiceTest TestApplications");
+        applicationMono =
+                applicationService.findByName(testApplication.getName())
+                        .switchIfEmpty(applicationService.create(testApplication));
+
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createLayoutWithNullPageId() {
+        Layout layout = new Layout();
+        Mono<Layout> layoutMono = layoutService.createLayout(null, layout);
+        StepVerifier
+                .create(layoutMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                        throwable.getMessage().equals(AppsmithError.INVALID_PARAMETER.getMessage(FieldName.PAGEID)))
+                .verify();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createLayoutWithInvalidPageID() {
+        Layout layout = new Layout();
+        String pageId = "Some random ID which can never be a page's ID";
+        Mono<Layout> layoutMono = layoutService.createLayout(pageId, layout);
+        StepVerifier
+                .create(layoutMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                        throwable.getMessage().equals(AppsmithError.INVALID_PARAMETER.getMessage(FieldName.PAGEID)))
+                .verify();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createValidLayout() {
+        Layout testLayout = new Layout();
+        JSONObject obj = new JSONObject();
+        obj.put("key1", "value1");
+        testLayout.setData(obj);
+
+        Page testPage = new Page();
+        testPage.setName("LayoutServiceTest createValidLayout Page");
+        Mono<Page> pageMono = pageService
+                .findByName(testPage.getName())
+                .switchIfEmpty(applicationMono
+                        .map(application -> {
+                            testPage.setApplicationId(application.getId());
+                            return testPage;
+                        })
+                        .flatMap(pageService::save));
+        layoutMono = pageMono
+                .flatMap(page -> layoutService.createLayout(page.getId(), testLayout));
+
+        StepVerifier
+                .create(layoutMono)
+                .assertNext(layout -> {
+                    assertThat(layout).isNotNull();
+                    assertThat(layout.getId()).isNotNull();
+                    assertThat(layout.getData().equals(obj));
+                })
+                .verifyComplete();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void updateLayoutInvalidPageId() {
+        Layout testLayout = new Layout();
+        JSONObject obj = new JSONObject();
+        obj.put("key", "value");
+        testLayout.setData(obj);
+        AtomicReference<String> pageId = new AtomicReference<>();
+
+        Page testPage = new Page();
+        testPage.setName("LayoutServiceTest updateLayoutInvalidPage");
+        Mono<Page> pageMono = pageService
+                .findByName(testPage.getName())
+                .switchIfEmpty(applicationMono
+                        .map(application -> {
+                            testPage.setApplicationId(application.getId());
+                            return testPage;
+                        })
+                        .flatMap(pageService::save));
+
+        Layout startLayout = pageMono
+                .flatMap(page -> {
+                    pageId.set(page.getId());
+                    return layoutService.createLayout(page.getId(), testLayout);
+                }).block();
+
+        Layout updateLayout = new Layout();
+        obj = new JSONObject();
+        obj.put("key", "value-updated");
+        updateLayout.setData(obj);
+
+        Mono<Layout> updatedLayoutMono = layoutService.updateLayout("random-impossible-id-page", startLayout.getId(), updateLayout);
+
+        StepVerifier
+                .create(updatedLayoutMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                        throwable.getMessage().equals(AppsmithError.INVALID_PARAMETER.getMessage(FieldName.PAGEID + " or " + FieldName.LAYOUTID)))
+                .verify();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void updateLayoutValidPageId() {
+        Layout testLayout = new Layout();
+        JSONObject obj = new JSONObject();
+        obj.put("key", "value");
+        testLayout.setData(obj);
+
+        Page testPage = new Page();
+        testPage.setName("LayoutServiceTest updateLayoutValidPage");
+        Page page = pageService
+                .findByName(testPage.getName())
+                .switchIfEmpty(applicationMono
+                        .map(application -> {
+                            testPage.setApplicationId(application.getId());
+                            return testPage;
+                        })
+                        .flatMap(pageService::save))
+                .block();
+
+        Layout startLayout = layoutService.createLayout(page.getId(), testLayout).block();
+
+        Layout updateLayout = new Layout();
+        JSONObject obj1 = new JSONObject();
+        obj1.put("key1", "value-updated");
+        updateLayout.setData(obj);
+
+        Mono<Layout> updatedLayoutMono = layoutService.updateLayout(page.getId(), startLayout.getId(), updateLayout);
+
+        StepVerifier
+                .create(updatedLayoutMono)
+                .assertNext(layout -> {
+                    assertThat(layout).isNotNull();
+                    assertThat(layout.getId()).isNotNull();
+                    assertThat(layout.getData().equals(obj1));
+                })
+                .verifyComplete();
+    }
+
+    @After
+    public void purgePages() {
+        pageService.deleteAll();
+    }
+}

app/server/src/test/java/com/appsmith/server/services/PageServiceTest.java

@@ -0,0 +1,99 @@
+package com.appsmith.server.services;
+
+import com.appsmith.server.constants.FieldName;
+import com.appsmith.server.domains.Application;
+import com.appsmith.server.domains.Page;
+import com.appsmith.server.exceptions.AppsmithError;
+import com.appsmith.server.exceptions.AppsmithException;
+import lombok.extern.slf4j.Slf4j;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.security.test.context.support.WithMockUser;
+import org.springframework.test.context.junit4.SpringRunner;
+import reactor.core.publisher.Mono;
+import reactor.test.StepVerifier;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+@Slf4j
+public class PageServiceTest {
+    @Autowired
+    PageService pageService;
+
+    @Autowired
+    ApplicationService applicationService;
+
+    Mono<Application> applicationMono;
+
+    @Before
+    @WithMockUser(username = "api_user")
+    public void setup() {
+        purgeAllPages();
+        Application application = new Application();
+        application.setName("PageAPI-Test-Application");
+        applicationMono = applicationService.create(application);
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createPageWithNullName() {
+        Page page = new Page();
+        Mono<Page> pageMono = Mono.just(page)
+                .flatMap(pageService::create);
+        StepVerifier
+                .create(pageMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                        throwable.getMessage().equals(AppsmithError.INVALID_PARAMETER.getMessage(FieldName.NAME)))
+                .verify();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createPageWithNullApplication() {
+        Page page = new Page();
+        page.setName("Page without application");
+        Mono<Page> pageMono = Mono.just(page)
+                .flatMap(pageService::create);
+        StepVerifier
+                .create(pageMono)
+                .expectErrorMatches(throwable -> throwable instanceof AppsmithException &&
+                throwable.getMessage().equals(AppsmithError.INVALID_PARAMETER.getMessage(FieldName.APPLICATIONID)))
+                .verify();
+    }
+
+    @Test
+    @WithMockUser(username = "api_user")
+    public void createValidPage() {
+        Page testPage = new Page();
+        testPage.setName("PageServiceTest TestApp");
+
+        Mono<Page> pageMono = applicationMono
+                .map(application -> {
+                    testPage.setApplicationId(application.getOrganizationId());
+                    return testPage;
+                })
+                .flatMap(pageService::create);
+
+        StepVerifier
+                .create(pageMono)
+                .assertNext(page -> {
+                    assertThat(page).isNotNull();
+                    assertThat(page.getId()).isNotNull();
+                    assertThat("PageServiceTest TestApp".equals(page.getName()));
+
+                })
+                .verifyComplete();
+    }
+
+    @After
+    public void purgeAllPages() {
+        pageService.deleteAll();
+    }
+
+}