feat: new theme + audodiscovery docs

docs/enterprise_edition/autodiscovery.md

@@ -0,0 +1,113 @@
+---
+icon: material/database-eye
+---
+
+# Automatic database discovery
+
+When deployed in front of AWS Aurora databases, PgDog can automatically detect the cluster instances and configure them in `pgdog.toml`. This is useful when Aurora uses replica autoscaling, which can add or remove instances at any time.
+
+## How it works
+
+This feature is **disabled** by default. To enable it, add at least one Aurora host to `pgdog.toml` and enable autodiscovery:
+
+=== "pgdog.toml"
+    ```toml
+    [[databases]]
+    name = "postgres"
+    host = "any-instance.account-id.region.rds.amazonaws.com"
+
+    [autodiscovery]
+    enabled = true
+    ```
+=== "Helm chart"
+    ```yaml
+    databases:
+      - name: "postgres"
+        host: "any-instance.account-id.region.rds.amazonaws.com"
+    autodiscovery:
+      enabled: true
+    ```
+
+When enabled, PgDog connects to the first available host for each database in the configuration and runs the [`aurora_replica_status()`](https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/aurora_replica_status.html) function to get the list of instances in the cluster.
+
+PgDog then replaces all entries in `pgdog.toml` with the discovered hosts and reloads its configuration automatically.
+
+### Autoscaling events
+
+To keep the list of databases in sync with Aurora autoscaling events, PgDog periodically queries the first available host in its config and runs the replica discovery function again.
+
+If the list of databases has changed, PgDog updates its config and reloads it. The interval for this check is configurable:
+
+=== "pgdog.toml"
+    ```toml
+    [autodiscovery]
+    enabled = true
+    check_interval = 5_000
+    ```
+
+=== "Helm chart"
+    ```yaml
+    autodiscovery:
+      enabled: true
+      checkInterval: 5000
+    ```
+
+### Filtering databases
+
+When enabled, autodiscovery runs for all databases in `pgdog.toml` by default. If some of your databases are not running on Aurora, or you want autodiscovery on some databases but not others, you can configure which ones it applies to:
+
+=== "pgdog.toml"
+    ```toml
+    [[databases]]
+    name = "postgres"
+    host = "any-instance.account-id.region.rds.amazonaws.com"
+
+    [[databases]]
+    name = "staging"
+    host = "not-aurora.account-id.region.rds.amazonaws.com"
+
+    [autodiscovery]
+    enabled = true
+
+    [[autodiscovery.databases]]
+    name = "postgres"
+    ```
+=== "Helm chart"
+    ```yaml
+    databases:
+      - name: "postgres"
+        host: "any-instance.account-id.region.rds.amazonaws.com"
+      - name: "staging"
+        host: "not-aurora.account-id.region.rds.amazonaws.com"
+    autodiscovery:
+      enabled: true
+      databases:
+        - name: "postgres"
+    ```
+
+In this example, only the `postgres` database will have autodiscovery enabled.
+
+!!! note "Configuring databases"
+    If you specify the `[[autodiscovery.databases]]` config, any database _not_ listed there will
+    not have autodiscovery enabled.
+
+### Replicas only
+
+If you're not using the read/write separation (single endpoint) feature of the [load balancer](../features/load-balancer/index.md#single-endpoint), you may want to configure read and write connection pools separately.
+
+To exclude the writer instance from host discovery for a read-only connection pool, set `replicas_only` in the autodiscovery database settings:
+
+=== "pgdog.toml"
+    ```toml
+    [[autodiscovery.databases]]
+    name = "prod_readonly"
+    replicas_only = true
+    ```
+
+=== "Helm chart"
+    ```yaml
+    autodiscovery:
+      databases:
+        - name: "postgres"
+          replicasOnly: true
+    ```

docs/features/transaction-mode.md

@@ -27,6 +27,7 @@ Transaction mode is **enabled** by default. This is controllable via configurati
     [general]
     pooler_mode = "transaction"
     ```
+    <br>
     ```yaml title="Helm chart"
     poolerMode: transaction
     ```
@@ -37,6 +38,7 @@ Transaction mode is **enabled** by default. This is controllable via configurati
     host = "127.0.0.1"
     pooler_mode = "transaction"
     ```
+    <br>
     ```yaml title="Helm chart"
     databases:
       - name: prod
@@ -50,6 +52,7 @@ Transaction mode is **enabled** by default. This is controllable via configurati
     database = "prod"
     pooler_mode = "transaction"
     ```
+    <br>
     ```yaml title="Helm chart"
     users:
       - name: alice
@@ -145,6 +148,7 @@ To use statement mode, you can configure it globally or per user/database, for e
     [general]
     pooler_mode = "statement"
     ```
+    <br>
     ```yaml title="Helm chart"
     poolerMode: statement
     ```
@@ -155,6 +159,7 @@ To use statement mode, you can configure it globally or per user/database, for e
     host = "127.0.0.1"
     pooler_mode = "statement"
     ```
+    <br>
     ```yaml title="Helm chart"
     databases:
       - name: prod
@@ -168,6 +173,7 @@ To use statement mode, you can configure it globally or per user/database, for e
     database = "prod"
     pooler_mode = "statement"
     ```
+    <br>
     ```yaml title="Helm chart"
     users:
       - name: alice