Attribute Service.

Attribute service provides CRUD operations for the attributes in Hypertrace.

What are Attributes?

An attribute is a granular piece of information that is present in Hypertrace and available for querying/displaying in the UI. An attribute encapsulates information like 1) the type of the data, 2) kind of aggregations allowed on it, 3) underlying service/source that can serve this data etc. This helps in building a generic framework of communication between the UI and the backend and also assists the backend to fetch data from the appropriate sources in a generic way.

Ex.

key: apiName,
value_kind: TYPE_STRING,
groupable : true,
display_name: Endpoint Name,
scope: API_TRACE,
sources: [QS],
type: ATTRIBUTE

While hypertrace offers a simple service model, it also permits storing certain fields in different backends. Attributes include tags to help locate the service hosting their corresponding data.

For example, apiName is generated from raw trace data streams. sources: [QS] communicates this, as Query Service is the api that queries that data (via Pinot).

You can check out structure of attribute here.

How are attributes created?

An initial list of attributes needed by Hypertrace are seeded from helm/configs but they can also be dynamically registered and queried using the APIs of AttributeService.

Description

Attribute service is a part of query architecture in Hypertrace and here is the use of it in context of its callers: hypertrace-graphql and gateway-service.

Hypertrace Query Architecture

Attribute service fetches all attributes relevant to the scope of what is being shown on UI from Mongo and where it also stores attributes. All of this metadata assists the UI and backend to perform things in a generic fashion, like

• All String attributes in the UI can have a different look at feel and also different operations that can be supported on them(in the explorer).
• The backend also uses part of the information(like the sources) to figure out where to fetch data from i.e. query-service vs entity-service.

Building locally

The Attribute service uses gradlew to compile/install/distribute. Gradle wrapper is already part of the source code. To build Attribute Service, run:

./gradlew dockerBuildImages

Testing

Running unit tests

Run ./gradlew test to execute unit tests.

Running integration tests

Run ./gradlew integrationTest to execute integration tests.

Testing image

With docker-compose

To test your image using the docker-compose setup follow the steps:

• Commit you changes to a branch say attribute-service-test.
• Go to hypertrace-service and checkout the above branch in the submodule.

cd attribute-service && git checkout attribute-service-test && cd ..

• Change tag for hypertrace-service from :main to :test in docker-compose file like this.

  hypertrace-service:
    image: hypertrace/hypertrace-service:test
    container_name: hypertrace-service
    ...

• and then run docker-compose up to test the setup.

With Helm setup

Add image repository and tag in values.yaml file here like below and then run ./hypertrace.sh install again and you can test your image!

attribute-service:
  image:
    repository: "hypertrace/attribute-service"
    tagOverride: "test"

Docker Image Source:

• DockerHub > Attribute service