# Tracker Stores

All conversations are stored within a tracker store.
Rasa Core provides implementations for different store types out of the box.
If you want to use another store, you can also build a custom tracker store by extending the TrackerStore class.

## Contents

- [InMemoryTrackerStore (default)](https://legacy-docs-v1.rasa.com/1.8.2/api/tracker-stores/#inmemorytrackerstore-default)

- [SQLTrackerStore](https://legacy-docs-v1.rasa.com/1.8.2/api/tracker-stores/#sqltrackerstore)

- [RedisTrackerStore](https://legacy-docs-v1.rasa.com/1.8.2/api/tracker-stores/#redistrackerstore)

- [MongoTrackerStore](https://legacy-docs-v1.rasa.com/1.8.2/api/tracker-stores/#mongotrackerstore)

- [Custom Tracker Store](https://legacy-docs-v1.rasa.com/1.8.2/api/tracker-stores/#custom-tracker-store)

## InMemoryTrackerStore (default)

**Description**  
InMemoryTrackerStore is the default tracker store. It is used if no other tracker store is configured. It stores the conversation history in memory.

**Note**  
As this store keeps all history in memory the entire history is lost if you restart Rasa Core.

**Configuration**  
To use the InMemoryTrackerStore no configuration is needed.

## SQLTrackerStore

**Description**  
`SQLTrackerStore` can be used to store the conversation history in an SQL database. Storing your trackers this way allows you to query the event database by sender_id, timestamp, action name, intent name and typename.

**Configuration**  
To set up Rasa Core with SQL the following steps are required:

1. Add required configuration to your endpoints.yml

```yaml
   tracker_store:
       type: SQL
       dialect: "sqlite"  # the dialect used to interact with the db
       url: ""  # (optional) host of the sql db, e.g. "localhost"
       db: "rasa.db"  # path to your db
       username:  # username used for authentication
       password:  # password used for authentication
       query: # optional dictionary to be added as a query string to the connection URL
         driver: my-driver
   ```

2. To start the Rasa Core server using your SQL backend,
add the `--endpoints` flag, e.g.:

```bash
   rasa run -m models --endpoints endpoints.yml
   ```

**Parameters**
- `domain` (default: `None`): Domain object associated with this tracker store
- `dialect` (default: `sqlite`): The dialect used to communicate with your SQL backend. Consult the [SQLAlchemy docs](https://docs.sqlalchemy.org/en/latest/core/engines.html#database-urls) for available dialects.
- `url` (default: `None`): URL of your SQL server
- `port` (default: `None`): Port of your SQL server
- `db` (default: `rasa.db`): The path to the database to be used
- `username` (default: `None`): The username which is used for authentication
- `password` (default: `None`): The password which is used for authentication
- `event_broker` (default: `None`): Event broker to publish events to
- `login_db` (default: `None`): Alternative database name to which initially connect, and create the database specified by db (PostgreSQL only)
- `query` (default: `None`): Dictionary of options to be passed to the dialect and/or the DBAPI upon connect

**Officially Compatible Databases**
- PostgreSQL
- Oracle > 11.0
- SQLite

**Oracle Configuration**  
To use the SQLTrackerStore with Oracle, there are a few additional steps. First, create a database `tracker` in your Oracle database and create a user with access to it. Create a sequence in the database with the following command, where `username` is the user you created:

```sql
   CREATE SEQUENCE username.events_seq;
   ```

Next you have to extend the Rasa Open Source image to include the necessary drivers and clients. First download the Oracle Instant Client from [here](https://www.oracle.com/database/technologies/instant-client/linux-x86-64-downloads.html), rename it to `oracle.rpm` and store it in the directory from where you’ll be building the docker image. Copy the following into a file called `Dockerfile`:

```dockerfile
   FROM rasa/rasa:|version|-full
   # Switch to root user to install packages
   USER root
   RUN apt-get update -qq \
   && apt-get install -y --no-install-recommends \
   alien \
   libaio1 \
   && apt-get clean \
   && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
   # Copy in oracle instaclient
   COPY oracle.rpm oracle.rpm
   # Install the Python wrapper library for the Oracle drivers
   RUN pip install cx-Oracle
   # Install Oracle client libraries
   RUN alien -i oracle.rpm
   USER 1001
   ```

Then build the docker image:

```bash
   docker build . -t rasa-oracle:|version|-oracle-full
   ```

Now you can configure the tracker store in the `endpoints.yml` as described above, and start the container. The `dialect` parameter with this setup will be `oracle+cx_oracle`.

## RedisTrackerStore

**Description**  
RedisTrackerStore can be used to store the conversation history in [Redis](https://redis.io/). Redis is a fast in-memory key-value store which can optionally also persist data.

**Configuration**  
To set up Rasa Core with Redis the following steps are required:

1. Start your Redis instance

2. Add required configuration to your endpoints.yml

```yaml
   tracker_store:
       type: redis
       url: <url of the redis instance, e.g. localhost>
       port: <port of your redis instance, usually 6379>
       db: <number of your database within redis, e.g. 0>
       password: <password used for authentication>
       use_ssl: <whether or not the communication is encrypted, default `false`>
   ```

3. To start the Rasa Core server using your configured Redis instance, add the `--endpoints` flag, e.g.:

```bash
   rasa run -m models --endpoints endpoints.yml
   ```

**Parameters**  
- `url` (default: `localhost`): The url of your redis instance
- `port` (default: `6379`): The port which redis is running on
- `db` (default: `0`): The number of your redis database
- `password` (default: `None`): Password used for authentication
  (`None` equals no authentication)
- `record_exp` (default: `None`): Record expiry in seconds
- `use_ssl` (default: `False`): whether or not to use SSL for transit encryption

## MongoTrackerStore

**Description**  
MongoTrackerStore can be used to store the conversation history in [Mongo](https://www.mongodb.com/). MongoDB is a free and open-source cross-platform document-oriented NoSQL database.

**Configuration**  
1. Start your MongoDB instance.

2. Add required configuration to your endpoints.yml

```yaml
   tracker_store:
       type: mongod
       url: <url to your mongo instance, e.g. mongodb://localhost:27017>
       db: <name of the db within your mongo instance, e.g. rasa>
       username: <username used for authentication>
       password: <password used for authentication>
       auth_source: <database name associated with the user’s credentials>
   ```
   You can also add more advanced configurations (like enabling ssl) by appending a parameter to the url field, e.g. mongodb://localhost:27017/?ssl=true

3. To start the Rasa Core server using your configured MongoDB instance,
add the `--endpoints` flag, e.g.:

```bash
   rasa run -m models --endpoints endpoints.yml
   ```

**Parameters**
- `url` (default: `mongodb://localhost:27017`): URL of your MongoDB
- `db` (default: `rasa`): The database name which should be used
- `username` (default: `None`): The username which is used for authentication
- `password` (default: `None`): The password which is used for authentication
- `auth_source` (default: `admin`): database name associated with the user’s credentials.
- `collection` (default: `conversations`): The collection name which is used to store the conversations

## Custom Tracker Store

**Description**  
If you require a tracker store which is not available out of the box, you can implement your own. This is done by extending the base class TrackerStore.

```python
class rasa.core.tracker_store.TrackerStore(domain, event_broker=None, retrieve_events_from_previous_conversation_sessions=False):
```

### Steps
1. Extend the TrackerStore base class. Note that your constructor has to provide a parameter `url`.

2. In your endpoints.yml put in the module path to your custom tracker store and the parameters you require:

```yaml
   tracker_store:
     type: path.to.your.module.Class
     url: localhost
     a_parameter: a value
     another_parameter: another value
   ```

👋 I can help you get started with Rasa and answer your technical questions.