(reedjosh) Initial build.

Signed-off-by: reedjosh <josh@thereedfamily.rocks>

.github/workflows/ci.yml

@@ -27,6 +27,7 @@ env:
   # XPKG_ACCESS_ID and XPKG_TOKEN secrets are set in the GitHub respository (or
   # organization) settings. Create a token at https://accounts.upbound.io.
   XPKG_ACCESS_ID: ${{ secrets.XPKG_ACCESS_ID }}
+  XPKG_TOKEN: ${{ secrets.XPKG_TOKEN }}
 
   # The package to push, without a version tag. The default matches GitHub. For
   # example xpkg.upbound.io/crossplane/function-template-go.

.gitignore

@@ -19,3 +19,4 @@
 
 # Go workspace file
 go.work
+tmp

README.md

@@ -1,26 +1,105 @@
-# function-template-go
+# function-extra-resources
 [![CI](https://github.com/crossplane/function-template-go/actions/workflows/ci.yml/badge.svg)](https://github.com/crossplane/function-template-go/actions/workflows/ci.yml)
 
-A template for writing a [composition function][functions] in [Go][go].
+A function for selecting extra resources via [composition function][functions]s in [Go][go].
 
-To learn how to use this template:
+## Using `function-extra-resources`
 
-* [Follow the guide to writing a composition function in Go][function guide]
-* [Learn about how composition functions work][functions]
-* [Read the function-sdk-go package documentation][package docs]
+Please see the example in `./examples`
 
-If you just want to jump in and get started:
+`function-extra-resources` is generally most useful in tandem with a function that can reference the many resources like
+`function-go-templating`.
 
-1. Replace `function-template-go` with your function in `go.mod`,
-   `package/crossplane.yaml`, and any Go imports. (You can also do this
-   automatically by running the `./init.sh <function-name>` script.)
-1. Update `input/v1beta1/` to reflect your desired input (and run `go generate`)
-1. Add your logic to `RunFunction` in `fn.go`
-1. Add tests for your logic in `fn_test.go`
-1. Update this file, `README.md`, to be about your function!
+### Creating objects from other's found in the local cluster.
+``` yaml
+apiVersion: apiextensions.crossplane.io/v1
+kind: Composition
+metadata:
+  name: function-environment-configs
+spec:
+  compositeTypeRef:
+    apiVersion: example.crossplane.io/v1
+    kind: XR
+  mode: Pipeline
+  pipeline:
+  - step: pull-extra-resources
+    functionRef:
+      name: function-extra-resources
+    input:
+      apiVersion: extra-resources.fn.crossplane.io/v1beta1
+      kind: Input
+      spec:
+        extraResources:
+          - kind: XCluster
+            into: XCluster
+            apiVersion: example.crossplane.io/v1
+            type: Selector
+            selector:
+              maxMatch: 2
+              minMatch: 1
+              matchLabels:
+                - key: type
+                  type: Value
+                  value: cluster
+  - step: go-templating
+    functionRef:
+      name: function-go-templating
+    input:
+      apiVersion: gotemplating.fn.crossplane.io/v1beta1
+      kind: GoTemplate
+      source: Inline
+      inline:
+        template: |
+            {{- $XClusters := index (index .context "apiextensions.crossplane.io/extra-resources") "XCluster" }}
+            {{- range $i, $A := $XClusters }}
+            ---
+            apiVersion: vault.upbound.io/v1beta1
+            kind: VaultRole
+            metadata:
+              annotations:
+                gotemplating.fn.crossplane.io/composition-resource-name: {{index (index $A "metadata") "name"}}
+            spec:
+              forProvider:
+            {{- end}}
+```
+
+
+## Installing the `function-extra-resources` Function into a Cluster
+
+``` shell
+cat <<EOF | kubectl apply -f -
+apiVersion: pkg.crossplane.io/v1beta1
+kind: Function
+metadata:
+  name: function-extra-resources
+spec:
+  package: xpkg.upbound.io/crossplane-contrib/function-extra-resources:latest
+EOF
+```
+
+## Local dev.
+
+### Air
+
+`air` is not strictly necessary, but helpful.
+
+Installing [air](https://github.com/cosmtrek/air) allows quick iterative local development.
+
+`air` is a live reloader that watches for local file changes.
+
+Once installed, running
+
+`air -- --insecure --debug --address localhost:9443`.
+
+Shoud get the function process/server build and running to serve CLI function requests.
+
+### After locally serving function-extra-resources
+
+`./run.sh` will use the crossplane CLI to run our basic example in `./examples`
+
+### Crossplane Function Basics
 
-This template uses [Go][go], [Docker][docker], and the [Crossplane CLI][cli] to
-build functions.
+This function uses [Go][go], [Docker][docker], and the [Crossplane CLI][cli].
 
 ```shell
 # Run code generation - see input/generate.go
@@ -41,4 +120,4 @@ $ crossplane xpkg build -f package --embed-runtime-image=runtime
 [function guide]: https://docs.crossplane.io/knowledge-base/guides/write-a-composition-function-in-go
 [package docs]: https://pkg.go.dev/github.com/crossplane/function-sdk-go
 [docker]: https://www.docker.com
-[cli]: https://docs.crossplane.io/latest/cli
+[cli]: https://docs.crossplane.io/latest/cli

air.toml

@@ -0,0 +1,5 @@
+# air.toml
+root = "."
+tmp_dir = "tmp"
+build_cmd = "go build -o ./tmp/main ."
+run_cmd = "./tmp/main"

example/composition.yaml

@@ -1,17 +1,60 @@
 apiVersion: apiextensions.crossplane.io/v1
 kind: Composition
 metadata:
-  name: function-template-go
+  name: function-environment-configs
 spec:
   compositeTypeRef:
     apiVersion: example.crossplane.io/v1
     kind: XR
   mode: Pipeline
   pipeline:
-  - step: run-the-template
+  - step: pull-extra-resources
     functionRef:
-      name: function-template-go
+      name: function-extra-resources
     input:
-      apiVersion: template.fn.crossplane.io/v1beta1
+      apiVersion: extra-resources.fn.crossplane.io/v1beta1
       kind: Input
-      example: "Hello world"
+      spec:
+        extraResources:
+          - kind: EnvironmentConfig
+            into: envConfs
+            apiVersion: apiextensions.crossplane.io/v1alpha1
+            type: Selector
+            selector:
+              maxMatch: 2
+              minMatch: 1
+              matchLabels:
+                - key: type
+                  type: Value
+                  value: cluster
+          - kind: XCluster
+            into: XCluster
+            apiVersion: example.crossplane.io/v1
+            type: Selector
+            selector:
+              maxMatch: 2
+              minMatch: 1
+              matchLabels:
+                - key: type
+                  type: Value
+                  value: cluster
+  - step: go-templating
+    functionRef:
+      name: function-go-templating
+    input:
+      apiVersion: gotemplating.fn.crossplane.io/v1beta1
+      kind: GoTemplate
+      source: Inline
+      inline:
+        template: |
+            {{- $XClusters := index (index .context "apiextensions.crossplane.io/extra-resources") "XCluster" }}
+            {{- range $i, $A := $XClusters }}
+            ---
+            apiVersion: vault.upbound.io/v1beta1
+            kind: VaultRole
+            metadata:
+              annotations:
+                gotemplating.fn.crossplane.io/composition-resource-name: {{index (index $A "metadata") "name"}}
+            spec:
+              forProvider:
+            {{- end}}

example/extraResources.yaml

@@ -0,0 +1,47 @@
+apiVersion: apiextensions.crossplane.io/v1alpha1
+kind: EnvironmentConfig
+metadata:
+  name: test-x1
+  labels:
+    type: cluster
+    metaName: test
+data:
+  realName: test-x1
+---
+apiVersion: apiextensions.crossplane.io/v1alpha1
+kind: EnvironmentConfig
+metadata:
+  name: test-y1
+  labels:
+    type: cluster
+    metaName: test
+data:
+  realName: test-y1
+---
+apiVersion: example.crossplane.io/v1
+kind: XCluster
+metadata:
+  name: net-staging-blue
+  labels:
+    type: cluster
+spec:
+  compositionRef:
+    name: compositecluster.example.crossplane.io
+  compositionSelector:
+    matchLabels:
+      provider: aws
+  compositionUpdatePolicy: Automatic
+---
+apiVersion: example.crossplane.io/v1
+kind: XCluster
+metadata:
+  name: net-staging-green
+  labels:
+    type: cluster
+spec:
+  compositionRef:
+    name: compositecluster.example.crossplane.io
+  compositionSelector:
+    matchLabels:
+      provider: aws
+  compositionUpdatePolicy: Automatic

example/functions.yaml

@@ -2,10 +2,17 @@
 apiVersion: pkg.crossplane.io/v1beta1
 kind: Function
 metadata:
-  name: function-template-go
+  name: function-extra-resources
   annotations:
     # This tells crossplane beta render to connect to the function locally.
     render.crossplane.io/runtime: Development
 spec:
   # This is ignored when using the Development runtime.
-  package: function-template-go
+  package: xpkg.upbound.io/crossplane-contrib/function-extra-resources:latest
+---
+apiVersion: pkg.crossplane.io/v1beta1
+kind: Function
+metadata:
+  name: function-go-templating
+spec:
+  package: xpkg.upbound.io/crossplane-contrib/function-go-templating:v0.4.1