Druid DB Connection (#71)

## Description

This PR refactors the init process and adds a new custom resource for druid connections.

The Init resource is now called SupersetDB and also tracks a status. it is first `Provisioned`. If possible (secret also deployed) a kubernetes `Job` is started and the status of the CR becomes `Initializing`. The job is watched, and depending on whether it successfully completes or not, the SupersetDB also becomes `Ready` or `Failed` respectively.

This change allows us to also depend on the DB being ready (or not). This is necessary for writing the druid connection information into the DB.

A new CRD is introduced: `DruidConnection`. It holds information about the superset DB it should write to, and the Druid cluster that should be connected. A new controller watches the discovery config map as well as the superset DB resources. Once all the dependencies are there (and `Ready`) a job is started, and the status is updated, just like it is done for the `SupersetDB`.

This is in line with the declarative philosophy of k8s; the spec reflects the desired state and the status tracks the actual underlying cluster. Also, with multiple controllers watching object states, control flow is delegated a bit to the API server. Before we were watching the job state manually, now we react to status changes which are given to us by the API server. The controllers only react to object changes.

This PR also relies on the Druid Discovery PR stackabletech/druid-operator#102

What wasn't done: If the DruidConnection resource is deleted, the actual connection is not deleted. The issue doesn't say that this is necessary, and there is no obvious, documented way to delete data sources from the commandline, we'd have to go into the database and delete stuff there. On the controller side we can use a [finalizer](https://github.com/kube-rs/kube-rs/blob/d90ee9706923ceddf94c3d50928bc390543af2fc/examples/secret_syncer.rs#L92-L102).



Co-authored-by: Felix Hennig <[email protected]>

CHANGELOG.md

@@ -2,14 +2,20 @@
 
 ## [Unreleased]
 
+### Added
+
+- Druid DB connections can now be configured in a custom resource ([#71]).
+
 ### Changed
 
 - Shut down gracefully ([#70]).
 - All dependencies upgraded. The upgrade to operator-rs 0.8.0 does not
   force the credentials secret to be set anymore in the custom resource
   but it is still required ([#82]).
+- - `operator-rs` `0.8.0` → `0.9.0` ([#71])
 
 [#70]: https://github.com/stackabletech/superset-operator/pull/70
+[#71]: https://github.com/stackabletech/superset-operator/pull/71
 [#82]: https://github.com/stackabletech/superset-operator/pull/82
 
 ## [0.2.0] - 2021-12-17

Cargo.toml

@@ -1,2 +1,3 @@
 [workspace]
 members = ["rust/crd", "rust/operator-binary"]
+

deploy/crd/druidconnection.crd.yaml

@@ -0,0 +1,73 @@
+---
+apiVersion: apiextensions.k8s.io/v1
+kind: CustomResourceDefinition
+metadata:
+  name: druidconnections.superset.stackable.tech
+spec:
+  group: superset.stackable.tech
+  names:
+    categories: []
+    kind: DruidConnection
+    plural: druidconnections
+    shortNames: []
+    singular: druidconnection
+  scope: Namespaced
+  versions:
+    - additionalPrinterColumns: []
+      name: v1alpha1
+      schema:
+        openAPIV3Schema:
+          description: "Auto-generated derived type for DruidConnectionSpec via `CustomResource`"
+          properties:
+            spec:
+              properties:
+                druid:
+                  properties:
+                    name:
+                      type: string
+                    namespace:
+                      type: string
+                  required:
+                    - name
+                    - namespace
+                  type: object
+                superset:
+                  properties:
+                    name:
+                      type: string
+                    namespace:
+                      type: string
+                  required:
+                    - name
+                    - namespace
+                  type: object
+              required:
+                - druid
+                - superset
+              type: object
+            status:
+              nullable: true
+              properties:
+                condition:
+                  enum:
+                    - Pending
+                    - Importing
+                    - Ready
+                    - Failed
+                  type: string
+                startedAt:
+                  description: Time is a wrapper around time.Time which supports correct marshaling to YAML and JSON.  Wrappers are provided for many of the factory methods that the time package offers.
+                  format: date-time
+                  nullable: true
+                  type: string
+              required:
+                - condition
+              type: object
+          required:
+            - spec
+          title: DruidConnection
+          type: object
+      served: true
+      storage: true
+      subresources:
+        status: {}

deploy/crd/supersetcluster.crd.yaml

@@ -22,6 +22,11 @@ spec:
           properties:
             spec:
               properties:
+                credentialsSecret:
+                  type: string
+                loadExamplesOnInit:
+                  nullable: true
+                  type: boolean
                 nodes:
                   nullable: true
                   properties:
@@ -32,10 +37,6 @@ spec:
                       type: object
                     config:
                       default: {}
-                      properties:
-                        credentialsSecret:
-                          default: ""
-                          type: string
                       type: object
                     configOverrides:
                       additionalProperties:
@@ -59,10 +60,6 @@ spec:
                             type: object
                           config:
                             default: {}
-                            properties:
-                              credentialsSecret:
-                                default: ""
-                                type: string
                             type: object
                           configOverrides:
                             additionalProperties:
@@ -125,6 +122,8 @@ spec:
                   description: Desired Superset version
                   nullable: true
                   type: string
+              required:
+                - credentialsSecret
               type: object
             status:
               nullable: true

deploy/crd/init.crd.yaml → deploy/crd/supersetdb.crd.yaml

@@ -2,61 +2,57 @@
 apiVersion: apiextensions.k8s.io/v1
 kind: CustomResourceDefinition
 metadata:
-  name: inits.command.superset.stackable.tech
+  name: supersetdbs.superset.stackable.tech
 spec:
-  group: command.superset.stackable.tech
+  group: superset.stackable.tech
   names:
     categories: []
-    kind: Init
-    plural: inits
+    kind: SupersetDB
+    plural: supersetdbs
     shortNames: []
-    singular: init
+    singular: supersetdb
   scope: Namespaced
   versions:
     - additionalPrinterColumns: []
       name: v1alpha1
       schema:
         openAPIV3Schema:
-          description: "Auto-generated derived type for InitCommandSpec via `CustomResource`"
+          description: "Auto-generated derived type for SupersetDBSpec via `CustomResource`"
           properties:
             spec:
               properties:
-                clusterRef:
-                  description: "A reference to a [`SupersetCluster`]"
-                  properties:
-                    name:
-                      nullable: true
-                      type: string
-                    namespace:
-                      nullable: true
-                      type: string
-                  type: object
                 credentialsSecret:
                   type: string
                 loadExamples:
                   type: boolean
+                supersetVersion:
+                  type: string
               required:
-                - clusterRef
                 - credentialsSecret
                 - loadExamples
+                - supersetVersion
               type: object
             status:
               nullable: true
               properties:
-                finishedAt:
-                  description: Time is a wrapper around time.Time which supports correct marshaling to YAML and JSON.  Wrappers are provided for many of the factory methods that the time package offers.
-                  format: date-time
-                  nullable: true
+                condition:
+                  enum:
+                    - Pending
+                    - Initializing
+                    - Ready
+                    - Failed
                   type: string
                 startedAt:
                   description: Time is a wrapper around time.Time which supports correct marshaling to YAML and JSON.  Wrappers are provided for many of the factory methods that the time package offers.
                   format: date-time
                   nullable: true
                   type: string
+              required:
+                - condition
               type: object
           required:
             - spec
-          title: Init
+          title: SupersetDB
           type: object
       served: true
       storage: true