refactor: update database accessory and related samples (#43)

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## What type of PR is this?

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## What this PR does / why we need it:
This PR refactors the database accessory model and updates related
samples.
## Which issue(s) this PR fixes:

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models/samples/pgadmin/base/base.k

@@ -0,0 +1,46 @@
+import models.schema.v1 as ac
+import models.schema.v1.workload as wl
+import models.schema.v1.workload.container as c
+import models.schema.v1.workload.network as n
+import models.schema.v1.accessories.postgres
+import models.schema.v1.workload.secret as sec
+
+# base.k declares reusable configurations for all stacks.
+pgadmin: ac.AppConfiguration {
+    workload: wl.Service {
+        containers: {
+            pgadmin: c.Container {
+                image: "dpage/pgadmin4:latest"
+                env: {
+                    "PGADMIN_DEFAULT_EMAIL": "[email protected]"
+                    "PGADMIN_DEFAULT_PASSWORD": "secret://pgadmin-secret/pgadmin-default-password"
+                    "PGADMIN_PORT": "80"
+                }
+                resources = {
+                    "cpu": "500m"
+                    "memory": "512Mi"
+                }
+            }
+        }
+        secrets: {
+            "pgadmin-secret": sec.Secret {
+                type: "opaque"
+                data: {
+                    "pgadmin-default-password": "*******"
+                }
+            }
+        }
+        replicas: 1
+        ports: [
+            n.Port {
+                port: 80
+            }
+        ]
+    }
+    database: {
+        pgadmin: postgres.PostgreSQL {
+            type: "cloud"
+            version: "14.0"
+        }
+    }
+}

models/samples/pgadmin/prod/kcl.yaml

@@ -0,0 +1,6 @@
+kcl_cli_configs:
+  file:
+    - ../base/base.k
+    - ./main.k
+  disable_none: false
+

models/samples/pgadmin/prod/main.k

@@ -0,0 +1,10 @@
+import models.schema.v1 as ac
+
+# main.k declares customized configurations for prod stack. 
+
+pgadmin: ac.AppConfiguration {
+    workload.containers.pgadmin: {
+        # prod stack has different image
+        image = "dpage/pgadmin4:8.0"
+    }
+}

models/samples/pgadmin/prod/stack.yaml

@@ -0,0 +1 @@
+name: prod

models/samples/pgadmin/project.yaml

@@ -0,0 +1,4 @@
+name: pgadmin
+generator:
+  type: AppConfiguration
+

models/samples/wordpress/base/base.k

@@ -1,11 +1,8 @@
 import models.schema.v1 as ac
-import models.schema.v1.trait as t
 import models.schema.v1.workload as wl
 import models.schema.v1.workload.container as c
-import models.schema.v1.workload.secret as sec
 import models.schema.v1.workload.network as n
-import models.schema.v1.monitoring as m
-import models.schema.v1.accessories.database as db
+import models.schema.v1.accessories.mysql
 
 # base.k declares reusable configurations for all stacks.
 wordpress: ac.AppConfiguration {
@@ -31,18 +28,10 @@ wordpress: ac.AppConfiguration {
             }
         ]
     }
-    # Declare dependent database resource
-    database: db.Database {
-        type: "alicloud"
-        engine: "MySQL"
-        version: "5.7"
-        size: 20
-        instanceType: "mysql.n2.serverless.1c"
-        category: "serverless_basic"
-
-        # SubnetID defines the virtual subnet ID associated with the VPC that the rds 
-        # instance will be created in. The rds instance won't be created in user's own VPC 
-        # if this field is not provided. 
-        subnetID: "your_subnet_id"
+    database: {
+        wordpress: mysql.MySQL {
+            type: "cloud"
+            version: "8.0"
+        }
     }
 }

models/samples/wordpress/prod/main.k

@@ -1,10 +1,39 @@
 import models.schema.v1 as ac
+import models.schema.v1.workload as wl
+import models.schema.v1.workload.container as c
+import models.schema.v1.workload.network as n
+import models.schema.v1.accessories.mysql
 
 # main.k declares customized configurations for prod stack.
 
 wordpress: ac.AppConfiguration {
-    workload.containers.wordpress: {
-        # prod stack has different image
-        image = "wordpress:4.8-apache"
+    workload: wl.Service {
+        containers: {
+            wordpress: c.Container {
+                image = "wordpress:6.3"
+                env = {
+                    "WORDPRESS_DB_HOST": "$(KUSION_DB_HOST_WORDPRESS)"
+                    "WORDPRESS_DB_USER": "$(KUSION_DB_USERNAME_WORDPRESS)"
+                    "WORDPRESS_DB_PASSWORD": "$(KUSION_DB_PASSWORD_WORDPRESS)"
+                    "WORDPRESS_DB_NAME": "mysql"
+                }
+                resources = {
+                    "cpu": "500m"
+                    "memory": "512Mi"
+                }
+            }
+        }
+        replicas = 1
+        ports = [
+            n.Port {
+                port: 80
+            }
+        ]
+    }
+    database = {
+        wordpress: mysql.MySQL {
+            type: "cloud"
+            version: "8.0"
+        }
     }
 }

models/schema/v1/accessories/mysql.k

@@ -0,0 +1,30 @@
+schema MySQL: 
+    """ MySQL describes the attributes to locally deploy or create a cloud provider
+    managed mysql database instance for the workload. 
+
+    Attributes
+    ----------
+    type: "local" | "cloud", defaults to Undefined, required. 
+        Type defines whether the mysql database is deployed locally or provided by 
+        cloud vendor. 
+    version: str, defaults to Undefined, required. 
+        Version defines the mysql version to use. 
+
+    Examples
+    --------
+    Instantiate a local mysql database with version of 5.7. 
+
+    import models.schema.v1.accessories.mysql
+
+    mysql: mysql.MySQL {
+        type: "local"
+        version: "5.7"
+    }
+    """
+
+    # The deployment mode of the mysql database. 
+    type:       "local" | "cloud"
+
+    # The mysql database version to use. 
+    version:    str
+

models/schema/v1/accessories/postgres.k

@@ -0,0 +1,30 @@
+schema PostgreSQL: 
+    """ PostgreSQL describes the attributes to locally deploy or create a cloud provider
+    managed postgresql database instance for the workload. 
+
+    Attributes
+    ----------
+    type: "local" | "cloud", defaults to Undefined, required. 
+        Type defines whether the postgresql database is deployed locally or provided by
+        cloud vendor. 
+    version: str, defaults to Undefined, required. 
+        Version defines the mysql version to use. 
+
+    Examples
+    --------
+    Instantiate a local postgresql database with image version of 14.0. 
+
+    import models.schema.v1.accessories.postgres
+
+    postgres: postgres.PostgreSQL {
+        type: "local"
+        version: "14.0"
+    }
+    """
+
+    # The deployment mode of the postgresql database. 
+    type:       "local" | "cloud"
+
+    # The postgresql database version to use. 
+    version:    str
+

models/schema/v1/app_configuration.k

@@ -1,7 +1,8 @@
 import models.schema.v1.workload as wl
 import models.schema.v1.trait as t
-import models.schema.v1.accessories.database as db
 import models.schema.v1.monitoring as m
+import models.schema.v1.accessories.mysql
+import models.schema.v1.accessories.postgres
 
 schema AppConfiguration:
     """ AppConfiguration is a developer-centric definition that describes how to run an Application.
@@ -15,6 +16,9 @@ schema AppConfiguration:
         includes Service and Job.
     monitoring: m.Prometheus, default is Undefined, optional.
         Monitoring specifies how to scrape Prometheus metrics for the workload.
+    database: {str:mysql.MySQL | postgres.PostgreSQL}, defualt is Undefined, optional. 
+        Database describes a locally deployed or a cloud provider managed database instance
+        for the workload. Currently supported database profile includes MySQL and PostgreSQL. 
     opsRule: t.OpsRule, default is Undefined, optional.
         OpsRule specifies collection of rules that will be checked for Day-2 operation.
     database: db.Database, default is Undefined, optional.
@@ -52,8 +56,8 @@ schema AppConfiguration:
     # OpsRule specifies collection of rules that will be checked for Day-2 operation.
     opsRule?:                   t.OpsRule
 
-    # Database describes a locally deployed or a cloud provider managed database instance for the workload.
-    database?:                  db.Database
+    # Database describes a locally deployed or a cloud provider managed database instance for the workload. 
+    database?:                  {str: mysql.MySQL | postgres.PostgreSQL}
 
     ###### Other metadata info
     # Labels and annotations can be used to attach arbitrary metadata as key-value pairs to resources.