Remove references to ReportingCore from Export Type code

[tsullivan]

Code in x-pack/plugins/reporting/server/export_types is planned to be removed from the reporting plugin and relocated into a new standalone plugin.

A large challenge with this task is to remove references to the ReportingCore object in that code. In the new destination plugin for the export types, there will not be the ReportingCore.

Affected code

# low-hanging fruit
x-pack/plugins/reporting/server/export_types/common/get_custom_logo.ts:  const fakeRequest = reporting.getFakeRequest(headers, spaceId, logger);
x-pack/plugins/reporting/server/export_types/common/get_custom_logo.ts:  const uiSettingsClient = await reporting.getUiSettingsClient(fakeRequest, logger);
x-pack/plugins/reporting/server/export_types/common/get_full_urls.ts:  const serverInfo = reporting.getServerInfo();
x-pack/plugins/reporting/server/export_types/common/get_full_urls.ts:  } = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/common/v2/get_full_redirect_app_url.ts:  } = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/common/v2/get_full_redirect_app_url.ts:  const serverInfo = reporting.getServerInfo();
x-pack/plugins/reporting/server/export_types/common/v2/get_full_redirect_app_url.test.ts:    reporting.getConfig = jest.fn(() => ({ kibanaServer: {} } as unknown as ReportingConfigType));
x-pack/plugins/reporting/server/export_types/common/v2/get_full_redirect_app_url.test.ts:    reporting.getServerInfo = jest.fn(() => ({
x-pack/plugins/reporting/server/export_types/printable_pdf/lib/generate_pdf.ts:  return reporting.getScreenshots(options).pipe(
x-pack/plugins/reporting/server/export_types/printable_pdf_v2/lib/generate_pdf.ts:  const screenshots$ = reporting.getScreenshots({ ...options, urls }).pipe(

# execute_job and create_job code will use a common approach: dependencies will be set into a class instance. See below
x-pack/plugins/reporting/server/export_types/csv_v2/create_job.ts:    const { discover: discoverPluginStart } = await reporting.getPluginStartDeps();
x-pack/plugins/reporting/server/export_types/png_v2/execute_job.ts:    const { encryptionKey } = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/csv_searchsource/execute_job.ts:  const { encryptionKey, csv: csvConfig } = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/csv_searchsource/execute_job.ts:    const fakeRequest = reporting.getFakeRequest(headers, job.spaceId, logger);
x-pack/plugins/reporting/server/export_types/csv_searchsource/execute_job.ts:    const uiSettings = await reporting.getUiSettingsClient(fakeRequest, logger);
x-pack/plugins/reporting/server/export_types/csv_searchsource/execute_job.ts:    const dataPluginStart = await reporting.getDataService();
x-pack/plugins/reporting/server/export_types/csv_searchsource/execute_job.ts:      (await reporting.getEsClient()).asScoped(fakeRequest),
x-pack/plugins/reporting/server/export_types/printable_pdf_v2/execute_job.ts:    const { encryptionKey } = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/csv_v2/execute_job.ts:  const config = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/csv_v2/execute_job.ts:    const fakeRequest = reporting.getFakeRequest(headers, job.spaceId, logger);
x-pack/plugins/reporting/server/export_types/csv_v2/execute_job.ts:    const uiSettings = await reporting.getUiSettingsClient(fakeRequest, logger);
x-pack/plugins/reporting/server/export_types/csv_v2/execute_job.ts:      await reporting.getPluginStartDeps();
x-pack/plugins/reporting/server/export_types/csv_v2/execute_job.ts:      (await reporting.getEsClient()).asScoped(fakeRequest),

# not being moved (need to remove this code asap)
x-pack/plugins/reporting/server/export_types/csv_searchsource_immediate/execute_job.ts:  const { csv: csvConfig } = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/csv_searchsource_immediate/execute_job.ts:    const dataPluginStart = await reporting.getDataService();
x-pack/plugins/reporting/server/export_types/csv_searchsource_immediate/execute_job.ts:    const uiSettings = await reporting.getUiSettingsServiceFactory(savedObjectsClient);
x-pack/plugins/reporting/server/export_types/csv_searchsource_immediate/execute_job.ts:      (await reporting.getEsClient()).asScoped(req),
x-pack/plugins/reporting/server/export_types/png/execute_job/index.ts:    const { encryptionKey } = reporting.getConfig();
x-pack/plugins/reporting/server/export_types/printable_pdf/execute_job/index.ts:    const { encryptionKey } = reporting.getConfig();

Colorized version:

A common approach for removing ReportingCore references from execute_job and create_job functions.

Reporting export types should be redesigned. Today, they are plain objects with stateless functions. They get
state from having the ReportingCore object passed in. By redesigning them as class instances, they can be
constructed with a "fresh" state that isn't dependent on ReportingCore. They can also have lifecycle methods to
receive stateful dependencies from the setup and start phases.

1. Reporting's export types will not get registered internally in the getExportTypesRegistry function.
2. Each export type will be created in phases:

   // x-pack/plugins/reporting/server/plugin.ts (export types have not yet been removed from the plugin)
   export class ReportingPlugin
     implements Plugin<ReportingSetup, ReportingStart, ReportingSetupDeps, ReportingStartDeps>
   {
     private logger: Logger;
     private reportingCore?: ReportingCore;
     private pdfExport: PdfExportType; // new
   
     constructor(private initContext: PluginInitializerContext<ReportingConfigType>) {
       this.logger = initContext.logger.get();
       const config = // ;
       this.pdfExport = new PdfExportType(config, this.logger); // new
       this.pngExport = new PngExportType(config, this.logger); // new
       this.csvExport = new CsvExportType(config, this.logger); // new
     }
   
     public setup(core: CoreSetup, plugins: ReportingSetupDeps) {
       const { http, status } = core;
   
       registerExportType(this.pdfExport); // pulled out of server/lib/export_types_registry.ts
       this.pdfExport.setup(core, plugins); // new
       this.pngExport.setup(core, plugins); // new
       this.csvExport.setup(core, plugins); // new
   
       const reportingCore = new ReportingCore(core, this.logger, this.initContext); // no longer given to any export type
       this.reportingCore = reportingCore;
   
       // .. skipped lines
   
       return reportingCore.getContract();
     }
   
     public start(core: CoreStart, plugins: ReportingStartDeps) {
       // ... skipped lines
   
       this.pdfExport.start(core, plugins); // new
       this.pngExport.start(core, plugins); // new
       this.csvExport.start(core, plugins); // new
   
       // ... skipped lines
   
       return reportingCore.getContract();
     }
   
     stop() {
       this.reportingCore?.pluginStop();
     }
   }

3. Defining export types without ReportingCore: the implementation of an export type definition will change from the plain object into a stateful instance of a
   class:

   class PdfExportType {
     constructor(private config: ReportingConfigType, logger: Logger) {
       this.logger = logger.get('pdf-export');
     }
   
     setup(coreSetup, setupDeps) {
       this.coreSetup = coreSetup;
       this.setupDeps = setupDeps;
     }
   
     start(coreStart, startDeps) {
       this.coreStart = coreStart;
       this.startDeps = startDeps;
     }
   
     createJob(jobParams: JobParamsPdf) {
       // create the payload that gets stored in .kibana-reporting-*
       return {
         ...jobParams,
         forceNow: new Date().toISOString(),
       };
     }
   
     async runTask(jobId, job, cancellationToken, stream) {
       // use the dependencies to execute the job and return the content through the stream
       const encryptionKey = this.config.encryptionKey;
       const headers = await decryptJobHeaders(encryptionKey, job.headers, this.logger)
   
       return this.startDeps.screenshotting.getScreenshots(job, job.locatorParams, { headers })....
     }
   }

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)

[rshen91]

This issue is completed 🥳