javascript - 生成缩略图 firebase javascript

问题描述

我在 firebase-cloud-function 上创建了一个触发函数，它可以为上传到云存储上的每个图像自动生成一个缩略图。但是每个上传操作我都收到了这个错误

我从firebase github repo复制/粘贴代码，然后按照所有说明进行操作，这是代码

    "use strict";

const functions = require("firebase-functions");
const mkdirp = require("mkdirp");
const admin = require("firebase-admin");
admin.initializeApp();
const spawn = require("child-process-promise").spawn;
const path = require("path");
const os = require("os");
const fs = require("fs");

// Max height and width of the thumbnail in pixels.
const THUMB_MAX_HEIGHT = 200;
const THUMB_MAX_WIDTH = 200;
// Thumbnail prefix added to file names.
const THUMB_PREFIX = "thumb_";

/**
 * When an image is uploaded in the Storage bucket We generate a thumbnail automatically using
 * ImageMagick.
 * After the thumbnail has been generated and uploaded to Cloud Storage,
 * we write the public URL to the Firebase Realtime Database.
 */
exports.generateThumbnail = functions.storage
  .object()
  .onFinalize(async (object) => {
    console.log("I'm an object hhhhhhhhhhhhhhhhhhhh");
    console.log(object);
    // File and directory paths.
    const filePath = object.name;
    const contentType = object.contentType; // This is the image MIME type
    const fileDir = path.dirname(filePath);
    const fileName = path.basename(filePath);
    const thumbFilePath = path.normalize(
      path.join(fileDir, `${THUMB_PREFIX}${fileName}`)
    );
    const tempLocalFile = path.join(os.tmpdir(), filePath);
    const tempLocalDir = path.dirname(tempLocalFile);
    const tempLocalThumbFile = path.join(os.tmpdir(), thumbFilePath);

    // Exit if this is triggered on a file that is not an image.
    if (!contentType.startsWith("image/")) {
      return functions.logger.log("This is not an image.");
    }

    // Exit if the image is already a thumbnail.
    if (fileName.startsWith(THUMB_PREFIX)) {
      return functions.logger.log("Already a Thumbnail.");
    }

    // Cloud Storage files.
    const bucket = admin.storage().bucket(object.bucket);
    const file = bucket.file(filePath);
    const thumbFile = bucket.file(thumbFilePath);
    const metadata = {
      contentType: contentType,
      // To enable Client-side caching you can set the Cache-Control headers here. Uncomment below.
      // 'Cache-Control': 'public,max-age=3600',
    };

    // Create the temp directory where the storage file will be downloaded.
    await mkdirp(tempLocalDir);
    // Download file from bucket.
    await file.download({ destination: tempLocalFile });
    functions.logger.log("The file has been downloaded to", tempLocalFile);
    // Generate a thumbnail using ImageMagick.
    await spawn(
      "convert",
      [
        tempLocalFile,
        "-thumbnail",
        `${THUMB_MAX_WIDTH}x${THUMB_MAX_HEIGHT}>`,
        tempLocalThumbFile,
      ],
      { capture: ["stdout", "stderr"] }
    );
    functions.logger.log("Thumbnail created at", tempLocalThumbFile);
    // Uploading the Thumbnail.
    await bucket.upload(tempLocalThumbFile, {
      destination: thumbFilePath,
      metadata: metadata,
    });
    functions.logger.log("Thumbnail uploaded to Storage at", thumbFilePath);
    // Once the image has been uploaded delete the local files to free up disk space.
    fs.unlinkSync(tempLocalFile);
    fs.unlinkSync(tempLocalThumbFile);
    // Get the Signed URLs for the thumbnail and original image.
    /* const results = await Promise.all([
      thumbFile.getSignedUrl({
        action: "read",
        expires: "03-01-2500",
      }),
      file.getSignedUrl({
        action: "read",
        expires: "03-01-2500",
      }),
    ]);
    functions.logger.log("Got Signed URLs.");
    const thumbResult = results[0];
    const originalResult = results[1];
    const thumbFileUrl = thumbResult[0];
    const fileUrl = originalResult[0];
    // Add the URLs to the Database
    /*await admin
      .database()
      .ref("images")
      .push({ path: fileUrl, thumbnail: thumbFileUrl });*/
    return; // functions.logger.log("Thumbnail URLs saved to database.");
  });

这是我的 IAM 配置

标签： javascriptfirebasegoogle-cloud-functionsgoogle-cloud-storage

javascript - 生成缩略图 firebase javascript

问题描述

解决方案

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