replace mit with lgpl (#530)

CHANGELOG.md

@@ -6,6 +6,7 @@ This release contains **BREAKING** changes. Make sure to read and apply upgrade
 
 - **[Breaking]** Remove ability to abort transactions using `throw(:abort)`. Please use `raise WaterDrop::Errors::AbortTransaction`.
 - **[Breaking]** Disallow (similar to ActiveRecord) exiting transactions with `return`, `break` or `throw`.
+- **[Breaking]** License changed from MIT to LGPL with an additional commercial option. Note: there is no commercial code in this repository. The commercial license is available for companies unable to use LGPL-licensed software for legal reasons.
 - [Enhancement] Make variants fiber safe.
 - [Enhancement] In transactional mode do not return any `dispatched` messages as none will be dispatched due to rollback.
 - [Fix] Ensure, that `:dispatched` key for `#produce_many_sync` always contains delivery handles (final) and not delivery reports.

LICENSE

@@ -0,0 +1,17 @@
+Copyright (c) Maciej Mensfeld
+
+WaterDrop is part of Karafka and it is an Open Source project licensed under the terms of
+the LGPLv3 license. Please see <https://github.com/karafka/karafka/blob/master/LICENSE-LGPL>
+for license text.
+
+Karafka ecosystem can also be used under commercial-friendly license, with commercial support and commercial components.
+
+All of the commercial components are present in the lib/karafka/pro and lib/karafka/web/pro
+directory of this repository and their usage requires commercial license agreement.
+
+By sending a pull request to the pro components, you are agreeing to transfer the copyright of your
+code to Maciej Mensfeld.
+
+You can find the commercial license in LICENSE-COMM <https://github.com/karafka/karafka/blob/master/LICENSE-COMM>.
+
+Please see https://karafka.io for purchasing options.

waterdrop.gemspec

@@ -14,7 +14,7 @@ Gem::Specification.new do |spec|
   spec.homepage      = 'https://karafka.io'
   spec.summary       = 'Kafka messaging made easy!'
   spec.description   = spec.summary
-  spec.license       = 'MIT'
+  spec.licenses      = %w[LGPL-3.0-only Commercial]
 
   spec.add_dependency 'karafka-core', '>= 2.4.3', '< 3.0.0'
   spec.add_dependency 'karafka-rdkafka', '>= 0.15.1'