chore: cache templates data

app/server/appsmith-server/src/main/java/com/appsmith/server/dtos/CacheableApplicationJson.java

@@ -0,0 +1,13 @@
+package com.appsmith.server.dtos;
+
+import lombok.Data;
+
+import java.time.Instant;
+
+@Data
+public class CacheableApplicationJson {
+
+    ApplicationJson applicationJson;
+
+    Instant cacheExpiryTime;
+}

app/server/appsmith-server/src/main/java/com/appsmith/server/dtos/CacheableApplicationTemplate.java

@@ -0,0 +1,14 @@
+package com.appsmith.server.dtos;
+
+import lombok.Data;
+
+import java.time.Instant;
+import java.util.List;
+
+@Data
+public class CacheableApplicationTemplate {
+
+    List<ApplicationTemplate> applicationTemplateList;
+
+    Instant cacheExpiryTime;
+}

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

@@ -645,7 +645,7 @@ public enum AppsmithError {
             ErrorType.CONFIGURATION_ERROR,
             null),
     CLOUD_SERVICES_ERROR(
-            500,
+            400,
             AppsmithErrorCode.CLOUD_SERVICES_ERROR.getCode(),
             "Received error from cloud services {0}",
             AppsmithErrorAction.DEFAULT,

app/server/appsmith-server/src/main/java/com/appsmith/server/helpers/CacheableTemplateHelper.java

@@ -0,0 +1,147 @@
+package com.appsmith.server.helpers;
+
+import com.appsmith.external.converters.ISOStringToInstantConverter;
+import com.appsmith.server.dtos.ApplicationJson;
+import com.appsmith.server.dtos.ApplicationTemplate;
+import com.appsmith.server.dtos.CacheableApplicationJson;
+import com.appsmith.server.dtos.CacheableApplicationTemplate;
+import com.appsmith.server.exceptions.AppsmithError;
+import com.appsmith.server.exceptions.AppsmithException;
+import com.appsmith.server.services.ce.ApplicationTemplateServiceCEImpl;
+import com.appsmith.util.WebClientUtils;
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.reflect.TypeToken;
+import lombok.extern.slf4j.Slf4j;
+import org.jetbrains.annotations.NotNull;
+import org.springframework.http.HttpStatus;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.client.ExchangeStrategies;
+import org.springframework.web.reactive.function.client.WebClient;
+import org.springframework.web.util.UriComponents;
+import org.springframework.web.util.UriComponentsBuilder;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+import java.lang.reflect.Type;
+import java.time.Instant;
+import java.util.HashMap;
+import java.util.Map;
+
+@Slf4j
+@Component
+public class CacheableTemplateHelper {
+    // Template metadata is used for showing the preview of the template
+
+    CacheableApplicationTemplate applicationTemplateList = new CacheableApplicationTemplate();
+
+    Map<String, CacheableApplicationJson> cacheableApplicationJsonMap = new HashMap<>();
+    private static final int CACHE_LIFE_TIME_IN_SECONDS = 60 * 60 * 24; // 24 hours
+
+    public Mono<CacheableApplicationTemplate> getTemplates(String releaseVersion, String baseUrl) {
+
+        if (applicationTemplateList == null) {
+            applicationTemplateList = new CacheableApplicationTemplate();
+        }
+
+        if (applicationTemplateList.getCacheExpiryTime() != null
+                && isCacheValid(applicationTemplateList.getCacheExpiryTime())) {
+            return Mono.just(applicationTemplateList);
+        }
+
+        UriComponentsBuilder uriComponentsBuilder =
+                UriComponentsBuilder.newInstance().queryParam("version", releaseVersion);
+
+        // uriComponents will build url in format: version=version&id=id1&id=id2&id=id3
+        UriComponents uriComponents = uriComponentsBuilder.build();
+
+        return WebClientUtils.create(baseUrl + "/api/v1/app-templates?" + uriComponents.getQuery())
+                .get()
+                .exchangeToFlux(clientResponse -> {
+                    if (clientResponse.statusCode().equals(HttpStatus.OK)) {
+                        return clientResponse.bodyToFlux(ApplicationTemplate.class);
+                    } else if (clientResponse.statusCode().isError()) {
+                        log.error("Error fetching templates from cloud services. Status code: {}", clientResponse);
+                        return Flux.error(
+                                new AppsmithException(AppsmithError.CLOUD_SERVICES_ERROR, clientResponse.statusCode()));
+                    } else {
+                        return clientResponse.createException().flatMapMany(Flux::error);
+                    }
+                })
+                .collectList()
+                .map(applicationTemplates -> {
+                    applicationTemplateList.setApplicationTemplateList(applicationTemplates);
+                    applicationTemplateList.setCacheExpiryTime(Instant.now());
+                    return applicationTemplateList;
+                });
+    }
+
+    // Actual JSON object of the template
+    public Mono<CacheableApplicationJson> getApplicationByTemplateId(String templateId, String baseUrl) {
+        final String templateUrl = baseUrl + "/api/v1/app-templates/" + templateId + "/application";
+        /*
+         * using a custom url builder factory because default builder always encodes
+         * URL.
+         * It's expected that the appDataUrl is already encoded, so we don't need to
+         * encode that again.
+         * Encoding an encoded URL will not work and end up resulting a 404 error
+         */
+        final int size = 4 * 1024 * 1024; // 4 MB
+
+        if (cacheableApplicationJsonMap == null) {
+            cacheableApplicationJsonMap = new HashMap<>();
+        }
+
+        if (cacheableApplicationJsonMap.containsKey(templateId)
+                && isCacheValid(cacheableApplicationJsonMap.get(templateId).getCacheExpiryTime())) {
+            return Mono.just(getCacheableApplicationJsonCopy(cacheableApplicationJsonMap.get(templateId)));
+        }
+
+        final ExchangeStrategies strategies = ExchangeStrategies.builder()
+                .codecs(codecs -> codecs.defaultCodecs().maxInMemorySize(size))
+                .build();
+
+        WebClient webClient = WebClientUtils.builder()
+                .uriBuilderFactory(new ApplicationTemplateServiceCEImpl.NoEncodingUriBuilderFactory(templateUrl))
+                .exchangeStrategies(strategies)
+                .build();
+
+        return webClient
+                .get()
+                .retrieve()
+                .bodyToMono(String.class)
+                .map(jsonString -> {
+                    Gson gson = getGson();
+                    Type fileType = new TypeToken<ApplicationJson>() {}.getType();
+
+                    CacheableApplicationJson cacheableApplicationJson = new CacheableApplicationJson();
+                    cacheableApplicationJson.setApplicationJson(gson.fromJson(jsonString, fileType));
+                    cacheableApplicationJson.setCacheExpiryTime(Instant.now());
+
+                    // Remove/replace the value from cache
+                    cacheableApplicationJsonMap.put(templateId, cacheableApplicationJson);
+                    return getCacheableApplicationJsonCopy(cacheableApplicationJson);
+                })
+                .switchIfEmpty(
+                        Mono.error(new AppsmithException(AppsmithError.NO_RESOURCE_FOUND, "template", templateId)));
+    }
+
+    private CacheableApplicationJson getCacheableApplicationJsonCopy(CacheableApplicationJson src) {
+        Gson gson = getGson();
+        return gson.fromJson(gson.toJson(src), CacheableApplicationJson.class);
+    }
+
+    @NotNull private Gson getGson() {
+        return new GsonBuilder()
+                .registerTypeAdapter(Instant.class, new ISOStringToInstantConverter())
+                .create();
+    }
+
+    public boolean isCacheValid(Instant lastUpdatedAt) {
+        return Instant.now().minusSeconds(CACHE_LIFE_TIME_IN_SECONDS).isBefore(lastUpdatedAt);
+    }
+
+    public Map<String, CacheableApplicationJson> getCacheableApplicationJsonMap() {
+        return cacheableApplicationJsonMap;
+    }
+}

app/server/appsmith-server/src/main/java/com/appsmith/server/imports/internal/partial/PartialImportServiceCEImpl.java

@@ -1,6 +1,7 @@
 package com.appsmith.server.imports.internal.partial;
 
 import com.appsmith.external.constants.AnalyticsEvents;
+import com.appsmith.external.helpers.Stopwatch;
 import com.appsmith.external.models.CreatorContextType;
 import com.appsmith.external.models.Datasource;
 import com.appsmith.server.acl.AclPermission;
@@ -237,6 +238,7 @@ private Mono<BuildingBlockImportDTO> importResourceInPage(
                     if (applicationJson.getPageList() == null) {
                         return Mono.just(application);
                     }
+                    Stopwatch processStopwatch1 = new Stopwatch("Refactoring the widget in DSL ");
                     // The building block is stored as a page in an application
                     final JsonNode dsl = widgetRefactorUtil.convertDslStringToJsonNode(applicationJson
                             .getPageList()
@@ -264,6 +266,7 @@ private Mono<BuildingBlockImportDTO> importResourceInPage(
                             })
                             .collectList()
                             .flatMap(refactoredDsl -> {
+                                processStopwatch1.stopAndLogTimeInMillis();
                                 applicationJson.setWidgets(dsl.toString());
                                 return Mono.just(application);
                             });
@@ -414,14 +417,18 @@ public Mono<BuildingBlockResponseDTO> importBuildingBlock(BuildingBlockDTO build
         Mono<ApplicationJson> applicationJsonMono =
                 applicationTemplateService.getApplicationJsonFromTemplate(buildingBlockDTO.getTemplateId());
 
+        Stopwatch processStopwatch = new Stopwatch("Download Content from Cloud service");
         return applicationJsonMono.flatMap(applicationJson -> {
+            processStopwatch.stopAndLogTimeInMillis();
+            Stopwatch processStopwatch1 = new Stopwatch("Importing resource in db ");
             return this.importResourceInPage(
                             buildingBlockDTO.getWorkspaceId(),
                             buildingBlockDTO.getApplicationId(),
                             buildingBlockDTO.getPageId(),
                             branchName,
                             applicationJson)
                     .flatMap(buildingBlockImportDTO -> {
+                        processStopwatch1.stopAndLogTimeInMillis();
                         // Fetch layout and get new onPageLoadActions
                         // This data is not present in a client, since these are created
                         // after importing the block

app/server/appsmith-server/src/main/java/com/appsmith/server/services/ApplicationTemplateServiceImpl.java

@@ -3,6 +3,7 @@
 import com.appsmith.server.applications.base.ApplicationService;
 import com.appsmith.server.configurations.CloudServicesConfig;
 import com.appsmith.server.exports.internal.ExportService;
+import com.appsmith.server.helpers.CacheableTemplateHelper;
 import com.appsmith.server.helpers.ResponseUtils;
 import com.appsmith.server.imports.internal.ImportService;
 import com.appsmith.server.services.ce.ApplicationTemplateServiceCEImpl;
@@ -28,7 +29,8 @@ public ApplicationTemplateServiceImpl(
             ResponseUtils responseUtils,
             ApplicationPermission applicationPermission,
             ObjectMapper objectMapper,
-            SessionUserService sessionUserService) {
+            SessionUserService sessionUserService,
+            CacheableTemplateHelper cacheableTemplateHelper) {
         super(
                 cloudServicesConfig,
                 releaseNotesService,
@@ -40,6 +42,7 @@ public ApplicationTemplateServiceImpl(
                 responseUtils,
                 applicationPermission,
                 objectMapper,
-                sessionUserService);
+                sessionUserService,
+                cacheableTemplateHelper);
     }
 }