[Doc] Mention recommended file extension(s) for Arrow IPC

[asfimport]

As asked on the ML, we should probably recommend a file extension for Arrow IPC.

For  the Arrow IPC file format, our IANA application mentions ".arrow".

For the Arrow IPC stream, I don't think we mentioned anything, but perhaps ".arrows" is a reasonable suggestion.

This may be mentioned in the FAQ and/or in the format spec.

Reporter: Antoine Pitrou / @pitrou
Assignee: Weston Pace / @westonpace

PRs and other links:

• GitHub Pull Request #10512

_{Note: This issue was originally created as ARROW-13036. Please see the migration documentation for further details.}

[asfimport]

Antoine Pitrou / @pitrou:
cc @westonpace @wesm

[asfimport]

Weston Pace / @westonpace:
We did recommend .arrows in the IANA application.  Wording-wise it seems it would be a bit awkward to try and fit into either spot.  The FAQ doesn't really get down to that level of detail and is somewhat narrative.  I think it could belong in the format doc, perhaps adding it early before the tone turns technical and changing

 

FROM:

We define a “file format” supporting random access that is build with the stream format. The file starts and ends with a magic string ARROW1 (plus padding).

TO:

We define a “file format” supporting random access that is build with the stream format.  We recommend using ".arrow" as the file extension. The file starts and ends with a magic string ARROW1 (plus padding).

 

[asfimport]

Weston Pace / @westonpace:
"build" -> "built" while we are at it :D

[asfimport]

Antoine Pitrou / @pitrou:
The FAQ entry could be something like "Is there a recommended filename extension for Arrow files?".

[asfimport]

Weston Pace / @westonpace:
The FAQ subsections right now are (paraphrasing):

• What is Arrow?

• Why Arrow?

• What is the status of Arrow?

• How can I get Arrow?

• How can I get help with Arrow?

• How does Arrow compare to other projects?

   

  I don't think "What is the file extension for Arrow files?" fits in thematically.

[asfimport]

Antoine Pitrou / @pitrou:
Fair enough. @nealrichardson Thoughts?

[asfimport]

Neal Richardson / @nealrichardson:
IMO once the IANA application goes through, we should document this, probably in the IPC format docs.

[asfimport]

Antoine Pitrou / @pitrou:
I'm not sure the IANA application is required to document a file extension. The MIME type I agree.

[asfimport]

Antoine Pitrou / @pitrou:
Issue resolved by pull request 10512
#10512