docs: add simple Go guide

Signed-off-by: Tanguy ⧓ Herrmann <tanguy@dagger.io>

docs/guides/1228-go-ci.md

@@ -0,0 +1,33 @@
+---
+slug: /1227/go-ci
+displayed_sidebar: europa
+---
+
+# Go project CI
+
+We want to run some tests and build a Go project with the `go` cue package.
+
+## Plan
+
+The plan consist of 2 actions:
+
+- `test` for `go test`
+- `build` for `go build`
+
+both use the [Go dagger package](https://github.com/dagger/dagger/tree/main/pkg/universe.dagger.io/go)
+
+```cue file=../plans/go-ci/plan.cue
+```
+
+## Go project
+
+The project is a simple program that takes `$NAME` environment variable, use the [Go greeting package](https://github.com/dagger/dagger/tree/main/docs/plans/go-ci/hello/greeting) to print the `greeting.Greet()` out.
+
+```go file=../plans/go-ci/hello/main.go
+```
+
+```go file=../plans/go-ci/hello/greeting/greeting.go
+```
+
+```go file=../plans/go-ci/hello/greeting/greeting_test.go
+```

docs/plans/go-ci/hello/go.mod

@@ -0,0 +1,3 @@
+module dagger.io/testgreetci
+
+go 1.17

docs/plans/go-ci/hello/greeting/greeting.go

@@ -0,0 +1,7 @@
+package greeting
+
+import "fmt"
+
+func Greeting(name string) string {
+	return fmt.Sprintf("Hi %s!", name)
+}

docs/plans/go-ci/hello/greeting/greeting_test.go

@@ -0,0 +1,13 @@
+package greeting
+
+import "testing"
+
+func TestGreeting(t *testing.T) {
+	name := "Dagger Test"
+	expect := "Hi Dagger Test!"
+	value := Greeting(name)
+
+	if expect != value {
+		t.Fatalf("Hello(%s) = '%s', expected '%s'", name, value, expect)
+	}
+}

docs/plans/go-ci/hello/main.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"dagger.io/testgreetci/greeting"
+)
+
+func main() {
+	name := os.Getenv("NAME")
+	if name == "" {
+		name = "John Doe"
+	}
+	fmt.Printf(greeting.Greeting(name))
+}

docs/plans/go-ci/plan.cue

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"dagger.io/dagger"
+
+	"universe.dagger.io/go"
+	//"universe.dagger.io/bash"
+)
+
+dagger.#Plan & {
+	client: filesystem: "./hello": read: contents: dagger.#FS
+
+	actions: {
+		test: go.#Test & {
+			source:  client.filesystem."./hello".read.contents
+			package: "./..."
+		}
+
+		build: go.#Build & {
+			source: client.filesystem."./hello".read.contents
+		}
+	}
+
+}