Load Image with Content-Type "application/octet-stream”

[DiSleeper]

Is it possible to load an image with Content-Type "application/octet-stream”, cause the backend sends a file with this type, Glide can load this content type, but no luck with Coil.
Have an error "
java.lang.IllegalStateException: BitmapFactory returned a null bitmap. Often this means BitmapFactory could not decode the image data read from the input source (e.g. network, disk, or memory) as it's not encoded as a valid image format."

[lbj1203]

I have solved it, there are two ways, the first one uses a custom decoder and the other is a custom fetcher.
decoder: get SourceResult.source.source().readByteArray() data, and then convert it by yourself).
fetcher: Write the request by yourself, and then convert the requested data into a readable image file

[ToleubekRauan]

@lbj1203 Could you please share some code of your implementation?

[lbj1203]

`class CustomDecoder(
private val result: SourceResult,
private val options: Options,
private val imageLoader: ImageLoader
) : Decoder {
override suspend fun decode(): DecodeResult? {
result.mimeType?.let {
if (it.indexOf("application/octet-stream") > -1) {
val bytes = result.source.source().readByteArray()
var resultByte: ByteArray? = XImageLoader.decryptOrigin(
bytes,
XImageLoader.AES_KEY
)
val bim = BitmapFactory.decodeByteArray(resultByte, 0, resultByte!!.size)
return DecodeResult(
drawable = bim.toDrawable(options.context.resources),
isSampled = false,
)
} else {
return DecodeResult(
drawable = toDrawable(result.source.file().toFile()),
isSampled = false
)
}
}
return DecodeResult(drawable = toDrawable(result.source.file().toFile()), isSampled = false)
}

private fun toDrawable(file: File): Drawable {
    var drawable: Drawable? = null
    try {
        val fis = FileInputStream(file)
        val btm = BitmapFactory.decodeStream(fis)
        drawable = BitmapDrawable(options.context.resources, btm)
    } catch (e: java.lang.Exception) {
        return ColorDrawable(Color.BLUE)
    }
    return drawable!!
}

class Factory() : Decoder.Factory {
    override fun create(
        result: SourceResult,
        options: Options,
        imageLoader: ImageLoader
    ): Decoder? {
        if (isApplicable(result.source.source())) return null
        return CustomDecoder(result, options, imageLoader)
    }

    private fun isApplicable(source: BufferedSource): Boolean {
        return DecodeUtils.isGif(source) ||
                DecodeUtils.isAnimatedWebP(source) ||
                (SDK_INT >= 30 && DecodeUtils.isAnimatedHeif(source))
    }

}

}`
According to the framework, the file has been downloaded, and then I directly get the data of the file in the file, and then convert it.
If you are using a custom Fetcher, copy the httpFetcher directly, and then parse the data into an image before saving it to disk

[ToleubekRauan]

Thank you, btw, what is the "XImageLoader.decryptOrigin" library?

[lbj1203]

还有一种是添加Interceptor,拦截数据然后进行转换,再返回