CLI: How to ensure it is scriptable

[mnaamani]

The joystream/cli has good support for interactive style which is very helpful and user friendly for some of the commands that require a lot of input/arguments from the user, prompting user to enter values for fields, checking validity, offering list of choices etc. The output in many cases is presented in a human readable form, sometimes single liner and in many cases multiple tables with various number of columns.

In order for the cli to be script-able there are two key requirements:

1. It should be possible to not require any interactivity, and therefore we must ensure that all commands can be executed by providing all inputs through commandline arguments or by reading a file from stdin. I believe this is already the case for many commands.
2. The output should be optionally formatted in a simple to parse format, so the output can easily be piped to other commands and even the joystream/cli itself. Given the rich output many of the command output, JSON seems like a viable choice.

eg. I want to query MyVideos and get details of the curation status of one particular video. Currently this involves:

cli media:MyVideos
looking in list of videos for entity id of the video of interest
cli content-directory:entity $VIDEO_ID
looking in the properties table for the entity id that represents the curation status:
cli content-directory:entity $CURATION_STATUS_ID

If the MyVideos command outputted json like

[{
  "id": 5,
  "channel": 7
  "title": "MyVideo 1"
},
{
  "id": 6,
  "channel": 7
  "title": "MyVideo 2"
}]

and the content-directory:entity command could read a line from stdin to get the entity id, and output json like:

{
 "id": 5
 "properties": [ 
    a,
    b,
    c, // curation status entity id
 ]
}

we could write a command like:

cli media:MyVideos | jq '.[0] | .id' | cli content-directory:entity | jq '.properties | '.[2]' | cli:entity

┆Issue is synchronized with this Asana task by Unito

[mnaamani]

Ref to jq command: https://www.baeldung.com/linux/jq-command-json

[mnaamani]

The "query" I showed above can probably be made with a simple graphql query to the query node of course and I'm sure we will add support for the query node to the cli, but it should be thought of as the fallback/Swiss Army Knife and should be as capable as possible.

[mnaamani]

One bonus of being able to use the cli in a non-interactive way, is that it would be possible to more easily include it in e2e integration tests.