redis-cli --raw AI.MODELGET mymodel BLOB > model.ext doesn't round trip models

[guyroyse]

The documentation in commands.md is incorrect. Admittedly in a small way. It states:

You can also save it to the local file 'model.ext' with redis-cli like so:

$ redis-cli --raw AI.MODELGET mymodel BLOB > model.ext

However, you cannot. redis-cli will tack on a newline to the end of the blob when you use the file redirection. I confirmed this with a hex editor. The same thing happens with tensors (however tensors don't have documents saying this works). This isn't a problem with RedisAI per se, so much as a problem with (or limitation of) redis-cli.

Probably the best solution would be to remove this from the documentation. Or modify redis-cli to have a flag to suppress the new line on output.

[guyroyse]

Also, happy to send a pull request to remove the lines if that's preferable. 😉

[lantiga]

Hey @guyroyse, uh! Admittedly at this point I very likely never double checked...

It would be really great to have a flag in redis-cli to avoid the trailing newline, do you think there's room for it?

[guyroyse]

I think redis-cli would benefit greatly from what is a rather small change. I'm actually somewhat surprised the --raw option doesn't do this by default.

[gkorland]

@guyroyse Are you sure it's the redis-cli which adds newline?

[guyroyse]

Reasonably, but I could be wrong. The only thing I'm 100% sure of is that redis-cli --raw AI.MODELGET mymodel BLOB > model.ext returns a file that I cannot send back into RedsiAI because it has an superfluous newline in it.

[DvirDukhan]

@guyroyse redis/redis#7841 adds -D flag so you can define what will be the delimiter between raw responses. In our case, you want an empty string (default is \n). Note that you don't need the --raw addition when redirecting as it is automatically detected.
In our case:

redis-cli -D "" AI.MODELGET mymodel BLOB > model.ext

cc @lantiga @gkorland
PR currently merged to Redis unstable. It will be merged to Redis 6.2 unless new versions will get out sooner.