[FEATURE] Add version in code

[dblock]

Is your feature request related to a problem?

Looking at the code of the library one can't tell which version it is. Only a release tag makes it a certain version. This makes it difficult to reliably know what version users are reporting bugs against. We also likely want to use the version in the future to add a User-Agent header.

What solution would you like?

1. Add a version in code and/or composer.json, document incrementing it, follow semver.
2. Add a test that ensures version can be retrieved dynamically.

Do you have any additional context?

Examples of other libraries that do that: https://github.com/opensearch-project/opensearch-ruby/blob/6bafe83e7b7014c6a012399ec77a03b19d335993/lib/opensearch/version.rb#L28

[shyim]

We can just use InstalledVersions::getVersion('opensearch-project/opensearch-php'); and then we get the version, it's provided by the Composer package manager.

I would not add something to the source code.

[dblock]

I am not super familiar with how this is done in PHP, so just trying to learn ;)

That works for released versions, but what does this return, or I should probably ask, how does one use the code that is unreleased on main?

[shyim]

composer uses then the current branch, or we can set branch aliases, so when you are on branch 2.x, please use 2.999.999

[dblock]

So the PHP way of doing it is like so:

  "repositories": [
    {
      "type": "package",
      "package": {
        "name": "opensearch-project/opensearch-php",
        "version": "2.9999",
        "source": {
          "url": "https://github.com/opensearch-project/opensearch-php",
          "type": "git",
          "reference": "main"
        }
      }
    }
  ],
  "require": {
    "opensearch-project/opensearch-php": "^2.0"
  }

Having to specify the version like you suggest puts the burden on the user to know what version is on main currently. Isn't that an anti-pattern? Shouldn't code know what version it is?

[dblock]

Btw, if this is just not the way things are done in PHP we can close this.

[dblock]

So we do have a version in code, https://github.com/opensearch-project/opensearch-php/blob/main/src/OpenSearch/Client.php#L55, and it's out of date.