Add set-project-id function. (#518)

* Add set-project-id function.

* Addressed comments.

* Update go functions Makefile.

* Add processing of Kptfiles in sub-packages.

* Seatch for Kptfile by kind.

* Update set-project-id-simple example.

* Fix golangci-lint error.

* Add advanced example with sub-package.

* Update test diffs.

Co-authored-by: Andrey Udovenko <andu@google.com>

Author: andudo

examples/set-project-id-advanced/.expected/config.yaml

@@ -0,0 +1,5 @@
+testType: eval
+includeMetaResources: true
+image: gcr.io/kpt-fn/set-project-id:unstable
+args:
+  project-id: foo

examples/set-project-id-advanced/.expected/diff.patch

@@ -0,0 +1,46 @@
+diff --git a/resources.yaml b/resources.yaml
+index 9e4fea2..ff21ea3 100644
+--- a/resources.yaml
++++ b/resources.yaml
+@@ -19,6 +19,7 @@ metadata:
+   namespace: config-control # kpt-set: ${namespace}
+   annotations:
+     cnrm.cloud.google.com/force-destroy: "false"
++    cnrm.cloud.google.com/project-id: foo
+ spec:
+   storageClass: standard # kpt-set: ${storage-class}
+   uniformBucketLevelAccess: true
+diff --git a/setters.yaml b/setters.yaml
+index 1702bac..06515a7 100644
+--- a/setters.yaml
++++ b/setters.yaml
+@@ -5,3 +5,4 @@ metadata:
+ data:
+   namespace: config-control
+   storage-class: standard
++  project-id: foo
+diff --git a/subpkg/Kptfile b/subpkg/Kptfile
+index c96b2cd..2643351 100644
+--- a/subpkg/Kptfile
++++ b/subpkg/Kptfile
+@@ -2,3 +2,8 @@ apiVersion: kpt.dev/v1
+ kind: Kptfile
+ metadata:
+   name: subpkg
++pipeline:
++  mutators:
++  - image: gcr.io/kpt-fn/apply-setters:v0.1
++    configMap:
++      project-id: foo
+diff --git a/subpkg/resources.yaml b/subpkg/resources.yaml
+index 84a6d6a..d568a8f 100644
+--- a/subpkg/resources.yaml
++++ b/subpkg/resources.yaml
+@@ -3,5 +3,7 @@ kind: IAMServiceAccount
+ metadata:
+   name: iamserviceaccount-sample
+   namespace: config-control # kpt-set: ${namespace}
++  annotations:
++    cnrm.cloud.google.com/project-id: foo
+ spec:
+   displayName: Example Service Account

examples/set-project-id-advanced/.expected/verify-docs-config.yaml

@@ -0,0 +1,2 @@
+skip:
+   - Kptfile

examples/set-project-id-advanced/.krmignore

@@ -0,0 +1 @@
+.expected

examples/set-project-id-advanced/Kptfile

@@ -0,0 +1,8 @@
+apiVersion: kpt.dev/v1
+kind: Kptfile
+metadata:
+  name: test-blueprint
+pipeline:
+  mutators:
+    - image: gcr.io/kpt-fn/apply-setters:v0.1
+      configPath: setters.yaml

examples/set-project-id-advanced/README.md

@@ -0,0 +1,43 @@
+# set-project-id: Advanced Example
+
+### Overview
+
+This example shows how [`set-project-id`] function works on packages with
+sub-packages.
+
+Running `set-project-id` function on the example packed will:
+
+1.  Set `project-id`
+    [setter](https://catalog.kpt.dev/apply-setters/v0.1/?id=definitions).
+2.  Add `cnrm.cloud.google.com/project-id` annotation on
+    [Config Connector resources](https://cloud.google.com/config-connector/docs/reference/overview)
+    that don't have it.
+
+### Fetch the example package
+
+Get the example package by running the following commands:
+
+```shell
+kpt pkg get https://github.com/GoogleContainerTools/kpt-functions-catalog.git/examples/set-project-id-advanced
+```
+
+### Function invocation
+
+Invoke the function with the following command:
+
+```shell
+kpt fn eval set-project-id-advanced --include-meta-resources --image gcr.io/kpt-fn/set-project-id:unstable -- 'project-id=foo'
+```
+
+### Expected result
+
+1.  File setters.yaml will include `project-id: foo` setter.
+2.  In resources.yaml `my-test-project-second-bucket` StorageBucket resource
+    will include `cnrm.cloud.google.com/project-id: foo` annotation.
+3.  Kptfile in subpkg folder will include `apply-setters` mutator with
+    `project-id: foo` setter.
+4.  In resources.yaml in subpkg folder `iamserviceaccount-sample`
+    IAMServiceAccount resource will include `cnrm.cloud.google.com/project-id:
+    foo` annotation.
+
+[`set-project-id`]: https://catalog.kpt.dev/set-project-id/v0.1/

examples/set-project-id-advanced/resources.yaml

@@ -0,0 +1,46 @@
+apiVersion: storage.cnrm.cloud.google.com/v1beta1
+kind: StorageBucket
+metadata:
+  name: my-test-project-first-bucket # kpt-set: ${project-id}-first-bucket
+  namespace: config-control # kpt-set: ${namespace}
+  annotations:
+    cnrm.cloud.google.com/force-destroy: "false"
+    cnrm.cloud.google.com/project-id: my-test-project # kpt-set: ${project-id}
+spec:
+  storageClass: standard # kpt-set: ${storage-class}
+  uniformBucketLevelAccess: true
+  versioning:
+    enabled: false
+---
+apiVersion: storage.cnrm.cloud.google.com/v1beta1
+kind: StorageBucket
+metadata:
+  name: my-test-project-second-bucket # kpt-set: ${project-id}-second-bucket
+  namespace: config-control # kpt-set: ${namespace}
+  annotations:
+    cnrm.cloud.google.com/force-destroy: "false"
+spec:
+  storageClass: standard # kpt-set: ${storage-class}
+  uniformBucketLevelAccess: true
+  versioning:
+    enabled: false
+---
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: newnamespace
+---
+apiVersion: core.cnrm.cloud.google.com/v1beta1
+kind: ConfigConnectorContext
+metadata:
+  name: configconnectorcontext.core.cnrm.cloud.google.com
+  namespace: newnamespace
+spec:
+  googleServiceAccount: new-namespace-sa@project-id.iam.gserviceaccount.com # kpt-set: new-namespace-sa@${project-id}.iam.gserviceaccount.com
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: test-map
+data:
+  some-key: some-value

examples/set-project-id-advanced/setters.yaml

@@ -0,0 +1,7 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: setters
+data:
+  namespace: config-control
+  storage-class: standard

examples/set-project-id-advanced/subpkg/Kptfile

@@ -0,0 +1,4 @@
+apiVersion: kpt.dev/v1
+kind: Kptfile
+metadata:
+  name: subpkg

examples/set-project-id-advanced/subpkg/resources.yaml

@@ -0,0 +1,7 @@
+apiVersion: iam.cnrm.cloud.google.com/v1beta1
+kind: IAMServiceAccount
+metadata:
+  name: iamserviceaccount-sample
+  namespace: config-control # kpt-set: ${namespace}
+spec:
+  displayName: Example Service Account