Proposal: make krew info work with multiple indexes

[ahmetb]

Since we had 1 index up until now, krew index had been fairly easy to implement. It did not distinguish between Receipts or Plugins (ref: LoadManifestFromReceiptOrIndex).

In other words, an "installed" plugin could only come from the Plugin manifest with the same name –as there were no other index.

So now, by allowing multiple indexes, krew info now has to understand if:

krew info foo

means foo the installed plugin (could be from any index), or the default/foo uninstalled plugin.

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Option 1

I recommend we change krew info’s behavior. krew info foo means:

• show info of foo installed plugin (could be from any index)
• show info of foo uninstalled plugin (from default index)

To disambiguate an "uninstalled" plugin, the user can run krew info my-index/foo. However, if my-index/foo is installed, could the user have meant show the "installed" plugin?

Keep in mind that krew info works on plugins installed via --manifest (i.e. has no index, but recorded as default with #555).

I'm losing my train of thought here.
If you see a straightforward solution, let me know.
/cc @corneliusweig
cc: @chriskim06
/kind proposal
/area multi-index

[ahmetb]

Option 2

I think I found a simplification/refinement:

We change krew info's behavior to only look at "available" plugins. It never looks at installed plugin receipts.

krew info foo # -> show default/foo
krew info my-index/foo

Advantages:

• easy to document for us, and easy to understand for users
• if we want to show if the plugin showed is_installed:true/false in "krew info" output, we can just query receipt by name and match the source index name.

Disadvantages:

• plugins installed but that don't exist in an index (i.e. installed via --manifest) (or index is deleted ==not supported) won't show here. I think it's an acceptable trade-off.

[corneliusweig]

I generally prefer option 2 over option 1, because it is more predictable and yields the same result regardless on which machine the command is executed on.

To make our user's lives easier, we can offer them some guidance when no manifest is found. For example, when looking for plugin bar from my-index:

$ krew info bar
Plugin `default/bar` does not exist. Did you mean `krew info my-index/bar`?

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Lastly, the inconvenience about not being able to show info about plugins installed via --manifest is not a small thing IMO. Plugin devs will want to see how their info prints on screen and they should be able to. To that end, we could add an option --installed that will force reading the manifest from the receipts folder. WDYT?

[ahmetb]

Lastly, the inconvenience about not being able to show info about plugins installed via --manifest is not a small thing IMO. Plugin devs will want to see how their info prints on screen and they should be able to. To that end, we could add an option --installed that will force reading the manifest from the receipts folder. WDYT?

I think for those people, I'd much rather prefer if krew info --manifest exists. :) That way, we make info work on Plugin concept only.

[corneliusweig]

Yeah, that's even better.