Add tool to upgrade ACLs

[mangalaman93]

TODO

• Add docs
• Test the tool

This change is 

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[manishrjain]

Some comments.

Reviewed 2 of 2 files at r1.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @mangalaman93)

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contrib/aclupgrade/upgrade.go, line 1 at r1 (raw file):

package main

Add license.

Also, move it to a Dgraph subcommand called 'upgrade'. And inside the main, just have a flag for acl upgrade for now.

dgraph upgrade --acls -a "localhost:8080"

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contrib/aclupgrade/upgrade.go, line 42 at r1 (raw file):

	userName := flag.String("u", "", "Username to login to Dgraph cluster")
	password := flag.String("p", "", "Password to login to Dgraph cluster")
	deleteOld := flag.Bool("d", false, "Delete the older ACL predicates")

Maybe we should delete by default. Otherwise, a re-run of this script would end up duplicating the rules. Do the deletion only after successful mutation.

[mangalaman93]

Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @manishrjain)

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contrib/aclupgrade/upgrade.go, line 1 at r1 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

Add license.

Also, move it to a Dgraph subcommand called 'upgrade'. And inside the main, just have a flag for acl upgrade for now.

dgraph upgrade --acls -a "localhost:8080"

Done.

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contrib/aclupgrade/upgrade.go, line 42 at r1 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

Maybe we should delete by default. Otherwise, a re-run of this script would end up duplicating the rules. Do the deletion only after successful mutation.

Done.

[manishrjain]

Reviewed 3 of 4 files at r2, 1 of 1 files at r3.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @danielmai, @mangalaman93, @manishrjain, and @MichaelJCompton)