immich-public-proxy/app/src/render.ts

import immich from './immich'
import { Response } from 'express-serve-static-core'
import { Asset, AssetType, ImageSize, IncomingShareRequest, SharedLink } from './types'
import { getConfigOption } from './functions'

class Render {
  lgConfig

  constructor () {
    this.lgConfig = getConfigOption('lightGallery', {})
  }

  /**
   * Stream data from Immich back to the client
   */
  async assetBuffer (req: IncomingShareRequest, res: Response, asset: Asset, size?: ImageSize) {
    // Prepare the request
    size = size === ImageSize.thumbnail ? ImageSize.thumbnail : ImageSize.original
    const subpath = asset.type === AssetType.video ? '/video/playback' : '/' + size
    const headers = { range: '' }
    if (asset.type === AssetType.video && req.range) {
      const start = req.range.replace(/bytes=/, '').split('-')[0]
      const startByte = parseInt(start, 10) || 0
      const endByte = startByte + 2499999
      headers.range = `bytes=${startByte}-${endByte}`
    }
    const url = immich.buildUrl(immich.apiUrl() + '/assets/' + encodeURIComponent(asset.id) + subpath, {
      key: asset.key,
      password: asset.password
    })
    const data = await fetch(url, { headers })

    // Return the response to the client
    if (data.status >= 200 && data.status < 300) {
      // Populate the response headers
      ['content-type', 'content-length', 'last-modified', 'etag', 'content-range']
        .forEach(header => {
          const value = data.headers.get(header)
          if (value) res.setHeader(header, value)
        })
      if (headers.range) res.status(206) // Partial Content
      // Return the body
      await data.body?.pipeTo(
        new WritableStream({
          write (chunk) {
            res.write(chunk)
          }
        })
      )
      res.end()
    } else {
      res.status(404).send()
    }
  }

  /**
   * Render a gallery page for a given SharedLink, using EJS and lightGallery.
   *
   * @param res - ExpressJS Response
   * @param share - Immich `shared-link` containing the assets to show in the gallery
   * @param [openItem] - Immediately open a lightbox to the Nth item when the gallery loads
   */
  async gallery (res: Response, share: SharedLink, openItem?: number) {
    const items = []
    for (const asset of share.assets) {
      let video
      if (asset.type === AssetType.video) {
        // Populate the data-video property
        video = JSON.stringify({
          source: [
            {
              src: immich.videoUrl(share.key, asset.id, asset.password),
              type: await immich.getContentType(asset)
            }
          ],
          attributes: {
            preload: false,
            controls: true
          }
        })
      }
      items.push({
        originalUrl: immich.photoUrl(share.key, asset.id, undefined, asset.password),
        thumbnailUrl: immich.photoUrl(share.key, asset.id, ImageSize.thumbnail, asset.password),
        video
      })
    }
    res.render('gallery', {
      items,
      openItem,
      title: this.title(share),
      lgConfig: getConfigOption('lightGallery', {})
    })
  }

  /**
   * Attempt to get a title from the link description or the album title
   */
  title (share: SharedLink) {
    return share.description || share?.album?.albumName || ''
  }
}

const render = new Render()

export default render