mwoffliner drops downloaded images from zim creation if imagemin toolchain fails processing them

[cm8]

mwoffliner/src/Downloader.ts

Lines 504 to 521 in ad5dc1d

	} else {
	resp.data = await (imagemin as any).buffer(resp.data, imageminOptions.get('default').get(resp.headers['content-type'])).catch(() => {
	return resp.data
	})
	}
	return true
	}
	return false
	}
	private getContentCb = async (url: string, handler: any): Promise<void> => {
	logger.info(`Downloading [${url}]`)
	try {
	if (this.optimisationCacheUrl && isImageUrl(url)) {
	this.downloadImage(url, handler)
	} else {
	const resp = await axios(url, this.arrayBufferRequestOptions)
	await this.getCompressedBody(resp)

The catch in line 505 seems to miss an error handler: If the imagemin call fails, then a successfully downloaded image will be dropped from ZIM creation. mwoffliner can do better in these cases: if the size reduction fails, log and take the downloaded original.

---

As an example for a possibly failing image see
https://upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Schleiflade_Tontraktur_Animation.gif/120px-Schleiflade_Tontraktur_Animation.gif

Prior to kohler/gifsicle@0e02f7b this file would fail a gifsicle run and thus not be included in any zim even if the resource successfully downloaded..