fix(striker-ui-api): read server screenshot from memory instead of through job

striker-ui-api/src/lib/consts/ENV.ts

@@ -33,13 +33,3 @@ export const PUID = resolveUid(process.env.PUID ?? 'striker-ui-api');
  * @default PUID
  */
 export const PGID = resolveGid(process.env.PGID ?? PUID);
-
-/**
- * Get server screenshot job timeout in milliseconds. The job will be
- * forced to progress 100 if it doesn't start within this time limit.
- *
- * @default 30000
- */
-export const GET_SERVER_SCREENSHOT_TIMEOUT = Number.parseInt(
-  process.env.GET_SERVER_SCREENSHOT_TIMEOUT ?? '30000',
-);

striker-ui-api/src/lib/request_handlers/server/getServerDetail.ts

@@ -1,25 +1,12 @@
 import assert from 'assert';
 import { RequestHandler } from 'express';
-import { ReadStream, createReadStream, writeFileSync } from 'fs';
+import { existsSync, readFileSync } from 'fs';
 import path from 'path';
 
-import {
-  GET_SERVER_SCREENSHOT_TIMEOUT,
-  REP_UUID,
-  SERVER_PATHS,
-} from '../../consts';
+import { REP_UUID, SERVER_PATHS } from '../../consts';
 
-import { getLocalHostUUID, job, query, write } from '../../accessModule';
 import { sanitize } from '../../sanitize';
-import { mkfifo, rm, stderr, stdout } from '../../shell';
-
-const rmfifo = (path: string) => {
-  try {
-    rm(path);
-  } catch (rmfifoError) {
-    stderr(`Failed to clean up FIFO; CAUSE: ${rmfifoError}`);
-  }
-};
+import { stderr, stdout, stdoutVar } from '../../shell';
 
 export const getServerDetail: RequestHandler<
   ServerDetailParamsDictionary,
@@ -28,21 +15,18 @@ export const getServerDetail: RequestHandler<
   ServerDetailParsedQs
 > = async (request, response) => {
   const {
-    params: { serverUUID },
-    query: { ss, resize },
+    params: { serverUUID: serverUuid },
+    query: { ss },
   } = request;
 
-  const epoch = Date.now();
   const isScreenshot = sanitize(ss, 'boolean');
 
-  stdout(
-    `serverUUID=[${serverUUID}],epoch=[${epoch}],isScreenshot=[${isScreenshot}]`,
-  );
+  stdout(`serverUUID=[${serverUuid}],isScreenshot=[${isScreenshot}]`);
 
   try {
     assert(
-      REP_UUID.test(serverUUID),
-      `Server UUID must be a valid UUID; got [${serverUUID}]`,
+      REP_UUID.test(serverUuid),
+      `Server UUID must be a valid UUID; got [${serverUuid}]`,
     );
   } catch (assertError) {
     stderr(
@@ -53,161 +37,32 @@ export const getServerDetail: RequestHandler<
   }
 
   if (isScreenshot) {
-    let requestHostUUID: string, serverHostUUID: string;
-
-    try {
-      requestHostUUID = getLocalHostUUID();
-    } catch (subError) {
-      stderr(String(subError));
-
-      return response.status(500).send();
-    }
-
-    stdout(`requestHostUUID=[${requestHostUUID}]`);
-
-    try {
-      [[serverHostUUID]] = await query(`
-          SELECT server_host_uuid
-          FROM servers
-          WHERE server_uuid = '${serverUUID}';`);
-    } catch (queryError) {
-      stderr(`Failed to get server host UUID; CAUSE: ${queryError}`);
-
-      return response.status(500).send();
-    }
-
-    stdout(`serverHostUUID=[${serverHostUUID}]`);
-
-    const imageFifoName = `${serverUUID}_screenshot_${epoch}`;
-    const imageFifoPath = path.join(SERVER_PATHS.tmp.self, imageFifoName);
-
-    let fifoReadStream: ReadStream;
-
-    try {
-      mkfifo(imageFifoPath);
-
-      fifoReadStream = createReadStream(imageFifoPath, {
-        autoClose: true,
-        emitClose: true,
-        encoding: 'utf-8',
-      });
-
-      let imageData = '';
-
-      fifoReadStream.once('error', (readError) => {
-        stderr(`Failed to read from FIFO; CAUSE: ${readError}`);
-      });
-
-      fifoReadStream.once('close', () => {
-        stdout(`On close; removing FIFO at ${imageFifoPath}.`);
-
-        rmfifo(imageFifoPath);
+    const imageFileName = `${serverUuid}_screenshot`;
+    const imageFilePath = path.join(SERVER_PATHS.tmp.self, imageFileName);
 
-        return response.status(200).send({ screenshot: imageData });
-      });
+    stdoutVar(
+      { imageFileName, imageFilePath },
+      `Server ${serverUuid} image file: `,
+    );
 
-      fifoReadStream.on('data', (data) => {
-        const imageChunk = data.toString().trim();
-        const peekLength = 10;
+    const rsbody = { screenshot: '' };
 
-        stdout(
-          `${serverUUID} image chunk: ${
-            imageChunk.length > 0
-              ? `${imageChunk.substring(
-                  0,
-                  peekLength,
-                )}...${imageChunk.substring(
-                  imageChunk.length - peekLength - 1,
-                )}`
-              : 'empty'
-          }`,
+    if (existsSync(imageFilePath)) {
+      try {
+        rsbody.screenshot = readFileSync(imageFilePath, { encoding: 'utf-8' });
+      } catch (error) {
+        stderr(
+          `Failed to read image file at ${imageFilePath}; CAUSE: ${error}`,
         );
 
-        imageData += imageChunk;
-      });
-    } catch (prepPipeError) {
-      stderr(
-        `Failed to prepare FIFO and/or receive image data; CAUSE: ${prepPipeError}`,
-      );
-
-      rmfifo(imageFifoPath);
-
-      return response.status(500).send();
-    }
-
-    let resizeArgs = sanitize(resize, 'string');
-
-    if (!/^\d+x\d+$/.test(resizeArgs)) {
-      resizeArgs = '';
-    }
-
-    let jobUuid: string;
-
-    try {
-      jobUuid = await job({
-        file: __filename,
-        job_command: SERVER_PATHS.usr.sbin['anvil-get-server-screenshot'].self,
-        job_data: `server-uuid=${serverUUID}
-request-host-uuid=${requestHostUUID}
-resize=${resizeArgs}
-out-file-id=${epoch}`,
-        job_name: `get_server_screenshot::${serverUUID}::${epoch}`,
-        job_title: 'job_0356',
-        job_description: 'job_0357',
-        job_host_uuid: serverHostUUID,
-      });
-    } catch (subError) {
-      stderr(`Failed to queue fetch server screenshot job; CAUSE: ${subError}`);
-
-      return response.status(500).send();
+        return response.status(500).send();
+      }
     }
 
-    const timeoutId: NodeJS.Timeout = setTimeout<[string, string]>(
-      async (uuid, fpath) => {
-        const [[isNotInProgress]]: [[number]] = await query(
-          `SELECT
-            CASE
-              WHEN job_progress IN (0, 100)
-                THEN CAST(1 AS BOOLEAN)
-              ELSE CAST(0 AS BOOLEAN)
-            END AS is_job_started
-          FROM jobs
-          WHERE job_uuid = '${uuid}';`,
-        );
-
-        if (isNotInProgress) {
-          stdout(
-            `Discard job ${uuid} because it's not-in-progress after timeout`,
-          );
-
-          try {
-            const wcode = await write(
-              `UPDATE jobs SET job_progress = 100 WHERE job_uuid = '${uuid}';`,
-            );
-
-            assert(wcode === 0, `Write exited with code ${wcode}`);
-
-            writeFileSync(fpath, '');
-          } catch (error) {
-            stderr(`Failed to discard job ${uuid} on timeout; CAUSE: ${error}`);
-
-            return response.status(500).send();
-          }
-        }
-      },
-      GET_SERVER_SCREENSHOT_TIMEOUT,
-      jobUuid,
-      imageFifoPath,
-    );
-
-    fifoReadStream.once('data', () => {
-      stdout(`Receiving server screenshot image data; cancel timeout`);
-
-      clearTimeout(timeoutId);
-    });
+    return response.send(rsbody);
   } else {
     // For getting sever detail data.
 
-    response.status(200).send();
+    response.send();
   }
 };