Flowcache exercise README needs to be updated

[tfia]

exercises/flowcache/flowcache.p4 requires us to complement packet_in/out headers:

@controller_header("packet_out")
header packet_out_header_h {
    /* TODO: Add packet-out fields */
}

@controller_header("packet_in")
header packet_in_header_h {
    /* TODO: Add packet-in fields */
}

However, the README doesn't mention this, and suggests Run the (incomplete) starter code as Step 1. Obviously the incomplete starter code can't be compiled before complementing these headers. Also, there's no explicit hints about what fields should these headers contain.

[jafingerhut]

@Dscano Any thoughts on these comments?

[Dscano]

Hi @tfia, you’re right, thanks for pointing it out. Apologies for the unclear README; I missed the detailed explanation of packet-in and packet-out. I’ll update the README asap.

[Dscano]

Hi @tfia,

I’ve pushed an update to the clowcache README: #704.
As noted in the README, the packet-in and packet-out header fields are defined and available in the P4 code, so students can understand what these fields mean.

[tfia]

@Dscano Thanks for updating README!

I also found many TODOs in the initial mycontroller.py were already implemented. Is that expected?

[Dscano]

@Dscano Thanks for updating README!

I also found many TODOs in the initial mycontroller.py were already implemented. Is that expected?

Yes, 2–3 TODOs have already been implemented with basic solutions, so students can improve them by developing more efficient or customized versions.

[jafingerhut]

Addressed this issue by merging this PR: #704

If that PR does not fully address your concerns, feel free to reopen this issue, or create a new one.