Refactor MetadataService to Use ContentTransformer
#1069
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Motivation: Previously, the Central Dogma server in `MetadataService` would repeatedly attempt to commit until it succeeded. With the introduction of `ContentTransformer` in line#1064, the server can now handle transformations in a single attempt, avoiding unnecessary retries. Modifications: - Updated `MetadataService` to utilize `ContentTransformer` for commit operations. Result: - Improved efficiency in `MetadataService` by eliminating repeated commit attempts.
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Checked that:
- there are no significant differences between previous/migrated logic
- there is no additional IO/blocking calls within
ContentTransformer
I'm unsure about the scope since only some methods in MetadataService seem to be migrated while others haven't been migrated, but the changes look good to me
| final Tokens tokens = tokens(node); | ||
| final Token token = tokens.get(appId); // Raise an exception if not found. | ||
| if (token.deactivation() == null) { | ||
| throw new IllegalArgumentException("The token is already activated: " + appId); |
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Note: this type of logic may be less performant in practice since a lock is always held (whereas previously this was done with an optimistic-lock).
Having said this, I agree with this approach since this API is not used often and I prefer code clarity over minor optimizations.
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That's something I overlooked. 😅
If an exception is raised, the ZooKeeper lock won't be held at all.
As you mentioned, it won't be an issue in most cases. If it becomes a problem, I can update the implementation to read the content first.
That is correct. 👍
The rest of them are migrated in #1061 |
Motivation:
Previously, the Central Dogma server in
MetadataServicewould repeatedly attempt to commit whenChangeConflictExceptionis raised.With the introduction of
ContentTransformerin Add Transforming Content Push Command #1064, the server can now handle transformations in a single attempt, avoiding unnecessary retries.Modifications:
MetadataServiceto utilizeContentTransformerfor commit operations.Result:
MetadataServiceby eliminating repeated commit attempts.To-do:
tokenRepoandmetadataRepoinMetadataServiceinto its class respectively.