feat: add instructions file for cloudsql_postgres (#93)

docs/datastore/cloudsql_postgres.md

@@ -0,0 +1,150 @@
+# Setup and configure Cloud SQL for Postgres
+
+## Before you begin
+
+1. Make sure you have a Google Cloud project and billing is enabled.
+
+1. Set your `PROJECT_ID` environment variable:
+
+    ```bash
+    export PROJECT_ID=<YOUR_PROJECT_ID>
+    ```
+
+1. [Install](https://cloud.google.com/sdk/docs/install) the gcloud CLI.
+
+1. Set gcloud project:
+
+    ```bash
+    gcloud config set project $PROJECT_ID
+    ```
+
+1. Enable APIs:
+
+    ```bash
+    gcloud services enable sqladmin.googleapis.com \
+                           aiplatform.googleapis.com
+    ```
+
+1. [Install python][install-python] and set up a python [virtual environment][venv].
+
+1. Make sure you have python version 3.10+ installed.
+
+    ```bash
+    python -V
+    ```
+
+1. Download and install [postgres-client cli (`psql`)][install-psql].
+
+1. Install the [Cloud SQL Auth Proxy client][install-cloudsql-proxy].
+
+[install-python]: https://cloud.google.com/python/docs/setup#installing_python
+[venv]: https://cloud.google.com/python/docs/setup#installing_and_using_virtualenv
+[install-psql]: https://www.timescale.com/blog/how-to-install-psql-on-mac-ubuntu-debian-windows/
+[install-cloudsql-proxy]: https://cloud.google.com/sql/docs/postgres/connect-instance-auth-proxy#install-proxy
+
+
+## Create a Cloud SQL for PostgreSQL instance
+
+1. Set environment variables. For security reasons, use a different password for
+   `$DB_PASS` and note it for future use:
+
+    ```bash
+    export DB_PASS=my-cloudsql-pass
+    export DB_USER=postgres
+    export INSTANCE=my-cloudsql-instance
+    export REGION=us-central1
+    ```
+
+1. Create a PostgreSQL instance:
+
+    ```bash
+    gcloud sql instances create $INSTANCE \
+        --database-version=POSTGRES_14 \
+        --cpu=4 \
+        --memory=16GB \
+        --region=$REGION
+    ```
+
+1. Set password for postgres user:
+
+    ```bash
+    gcloud sql users set-password $DB_USER \
+        --instance=$INSTANCE \
+        --password=$DB_PASS
+    ```
+
+
+## Connect to the Cloud SQL instance
+
+1. Connect to instance using cloud sql proxy:
+
+    ```bash
+    ./cloud-sql-proxy $PROJECT_ID:$REGION:$INSTANCE
+    ```
+
+1. Verify you can connect to your instance with the `psql` tool. Enter
+   password for Cloud SQL (`$DB_PASS` environment variable set above) when prompted:
+
+    ```bash
+    psql "host=127.0.0.1 port=5432 sslmode=disable user=$DB_USER"
+    ```
+
+## Initialize data
+
+1. While connected using `psql`, create a database and switch to it:
+
+    ```bash
+    CREATE DATABASE assistantdemo;
+    \c assistantdemo
+    ```
+
+1. Install [`pgvector`][pgvector] extension in the database:
+
+    ```bash
+    CREATE EXTENSION vector;
+    ```
+
+1. Change into the retrieval service directory:
+
+    ```bash
+    cd genai-database-retrieval-app/retrieval_service
+    ```
+
+1. Install requirements:
+
+    ```bash
+    pip install -r requirements.txt
+    ```
+
+1. Make a copy of `example-config.yml` and name it `config.yml`.
+
+    ```bash
+    cp example-config.yml config.yml
+    ```
+
+1. Update `config.yml` with your database information.
+
+    ```bash
+    host: 0.0.0.0
+    datastore:
+      # Example for cloudsql_postgres.py provider
+      kind: "cloudsql-postgres"
+      # Update this with your project ID
+      project: <PROJECT_ID>
+      region: us-central1
+      instance: my-cloudsql-instance
+      # Update this with the database name
+      database: "assistantdemo"
+      # Update with database user, the default is `postgres`
+      user: "postgres"
+      # Update with database user password
+      password: "my-cloudsql-pass"
+    ```
+
+1. Populate data into database:
+
+    ```bash
+    python run_database_init.py
+    ```
+
+[pgvector]: https://github.com/pgvector/pgvector