Linuxbrew support

[mgreau]

On February 24th, @StudioMaX opened a PR for adding support of Linuxbrew.

As explained in the PR, the Elastic took the following decision:

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We discussed this topic internally and unfortunately, we are not going to add support for Linuxbrew in the short term.

We do support multiple ways to install the Elastic Stack on Linux distributions.
We prefer not to add a new system that is not part of our automation process yet and that we will not be able to fully support.

This decision may be revisited in the future

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@StudioMaX mentioned the following

Sometimes it's not possible to use yum/dnf/apt/zypper repositories or rpm/deb packages because we just don't have root privileges on the server. And the only way to install Elasticsearch is to use .tar.gz archives, which is far from ideal, since all the charms of package managers are missing (for example, just updating the application to the latest version is not so simple). This is why we using Linuxbrew.

[StudioMaX]

Hello here again,
Some changes have occurred since the creation of this bug:

1. Elasticsearch 7 support (and all other parallel packages with version 7) was added to the base Homebrew repository (for Mac) last year, and accordingly was added to the Linuxbrew repository (for Linux). From that moment on, the problem of this issue disappeared, as it was possible to use the official Linuxbrew repository.
2. Due to the recent changes in the Elastica license, packages in the base Homebrew and Linuxbrew repositories have been marked as deprecated, and most likely will not receive updates. See elasticsearch 7.10.2 + deprecate Homebrew/homebrew-core#69121 and kibana: deprecate Homebrew/homebrew-core#69122

Because of this change, it was again necessary to install Elasticsearch and everything else from some repository. But in this official Elastic Homebrew Tap, Linux support still was not added.

For me, as an end user, this looks like some kind of bureaucracy, due to the need to constantly monitor and install updates from the tar archives, or maintain a fork of this Tap for easy installation of updates.