In the GitHub Actions workflow:
- Update actions/checkout to the latest version
- Update actions/setup-java to the latest version (Java 21 already works
but is undocumented, the next version it will be thanks to
https://github.com/actions/setup-java/pull/538😀)
#### Context
Apache Cassandra is a popular open-source database created back in 2008.
This year with
[CEP30](https://cwiki.apache.org/confluence/display/CASSANDRA/CEP-30%3A+Approximate+Nearest+Neighbor%28ANN%29+Vector+Search+via+Storage-Attached+Indexes)
support for vector and similarity searches have been introduced.
Cassandra is very fast in read and write and is used as a cache by many
companies, it as an opportunity to implement the ChatMemoryStore. This
feature is expected for Cassandra 5 at the end of the year but some
docker images are already available.
DataStax AstraDb is a distribution of Apache Cassandra available as Saas
providing a free tier (free forever) of 80 millions queries/month.
[Registration](https://astra.datastax.com). The vector capability is
there production ready.
#### Data Modelling
With the proper data model in Cassandra we can perform both similarity
search, keyword search, metadata search.
```sql
CREATE TABLE sample_vector_table (
row_id text PRIMARY KEY,
attributes_blob text,
body_blob text,
metadata_s map<text, text>,
vector vector<float, 1536>
);
```
#### Implementation Throughts
- The **configuration** to connect to Astra and Cassandra are not
exactly the same so 2 different classes with associated builder are
provided:
[Astra](https://github.com/clun/langchain4j/blob/main/langchain4j/src/main/java/dev/langchain4j/store/embedding/cassandra/AstraDbEmbeddingConfiguration.java)
and [OSS
Cassandra](https://github.com/clun/langchain4j/blob/main/langchain4j/src/main/java/dev/langchain4j/store/embedding/cassandra/CassandraEmbeddingConfiguration.java).
A couple of fields are mutualized but creating a superclass to inherit
from lead to the use of Lombok `@SuperBuilder` and the Javadoc was not
able to found out what to do.
- Instead of passing a large number of arguments like other stores I
prefer to wrap them as a bean. With this trick you can add or remove
attributes, make then optional or mandatory at will. If you need to add
a new attribute in the configuration you do not have to change the
implementation of `XXXStore` and `XXXStoreImpl`
- I create an
[AstractEmbeddedStore<T>](https://github.com/clun/langchain4j/blob/main/langchain4j/src/main/java/dev/langchain4j/store/embedding/AbstractEmbeddingStore.java)
that could very well become the super class for any store. It handles
the different call of the real concrete implementation. (_delegate
pattern_). Some default implementation can be implemented
```java
/**
* Add a list of embeddings to the store.
*
* @param embeddings
* list of embeddings (hold vector)
* @return
* list of ids
*/
@Override
public List<String> addAll(List<Embedding> embeddings) {
Objects.requireNonNull(embeddings, "embeddings must not be null");
return embeddings.stream().map(this::add).collect(Collectors.toList());
}
```
The only method to implement at the Store level is:
```java
/**
* Initialize the concrete implementation.
* @return create implementation class for the store
*/
protected abstract EmbeddingStore<T> loadImplementation()
throws ClassNotFoundException, NoSuchMethodException, InstantiationException,
IllegalAccessException, InvocationTargetException;
```
-
[CassandraEmbeddedStore](https://github.com/clun/langchain4j/blob/main/langchain4j/src/main/java/dev/langchain4j/store/embedding/cassandra/CassandraEmbeddingStore.java#L30)
proposes 2 constructors, one could override the implementation class if
they want (extension point)
#### Tests
- Test classes are provided including some long form examples based on
classed found in `langchain4j-examples` but test are disabled.
- To start a local cassandra use docker and the
[docker-compose](https://github.com/clun/langchain4j/blob/main/langchain4j-cassandra/src/test/resources/docker-compose.yml)
```
docker compose up -d
```
- To run Test with Astra signin with your github account, create a token
(api Key) with role `Organization Administrator` following this
[procedure](https://awesome-astra.github.io/docs/pages/astra/create-token/#c-procedure)
<img width="926" alt="Screenshot 2023-09-06 at 18 14 12"
src="https://github.com/langchain4j/langchain4j/assets/726536/dfd2d9e5-09c9-4504-bfaa-31cfd87704a1">
- Pick the full value of the `token` from the json
<img width="713" alt="Screenshot 2023-09-06 at 18 15 53"
src="https://github.com/langchain4j/langchain4j/assets/726536/1be56234-dd98-4f59-af71-03df42ed6997">
- Create the environment variable `ASTRA_DB_APPLICATION_TOKEN`
```console
export ASTRA_DB_APPLICATION_TOKEN=AstraCS:....<your_token>
```
Some leftovers from an earlier (and now incorrect) CI configuration.
Modules that don't need to comply with the licenses need to deactivate
the relevant plugin on a case-by-case basis.
- all-minilm-l6-v2
- all-minilm-l6-v2-q
- e5-small-v2
- e5-small-v2-q
The idea is to give users an option to embed documents/texts in the same
Java process without any external dependencies.
ONNX Runtime is used to run models inside JVM.
Each model resides in it's own maven module (inside the jar).
The title says it all. Relying on [this maven
plugin](https://github.com/chonton/license-maven-plugin) for it.
Note that this adds a separate build step because we need a more recent
JDK to run the needed plugin.
This PR:
adds a github action for running unit tests
tests that require an OpenAI/HuggingFace token and hit their API are now considered integration tests (and have been renamed to end in IT)
integration tests are now run through a separate goal (mvn integration-test) via the maven-failsafe-plugin
to fix the PromptTemplate tests a Clock has been added to that class. Its constructor is now private: whether this is the convention we want to follow can be discussed
LangChain4j