internal/workflows: migrate workflows

This represents workflow documents via compound literals and removes
the ugly and footgun-heavy yaml documents.

Signed-off-by: Ophestra <cat@gensokyo.uk>

4 files changed, 423 insertions, 0 deletions

diff --git a/internal/workflows/doc.go b/internal/workflows/doc.go
new file mode 100644
index 00000000..6a9dc5e6
--- /dev/null
+++ b/internal/workflows/doc.go
@@ -0,0 +1,10 @@
+//go:build !workflows
+
+// The workflows program manages the .gitea directory to avoid having to write
+// yaml. It is never invoked directly or built for the distribution tarball.
+//
+// This program is an internal detail of the hakurei project and is not usable
+// on its own. It is not covered by the compatibility promise.
+package workflows
+
+//go:generate go run -tags=workflows .
diff --git a/internal/workflows/main.go b/internal/workflows/main.go
new file mode 100644
index 00000000..46f7e054
--- /dev/null
+++ b/internal/workflows/main.go
@@ -0,0 +1,149 @@
+//go:build workflows
+
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sync"
+)
+
+// KV represents a string to value pair.
+type KV[T any] struct {
+	K string
+	V T
+}
+
+// A Map represents an ordered set of key-value pairs.
+type Map[T any] []KV[T]
+
+// MarshalJSON encodes m as a key-value pair in JSON.
+func (m *Map[T]) MarshalJSON() ([]byte, error) {
+	if m == nil || len(*m) == 0 {
+		return []byte("{}"), nil
+	}
+
+	buf := bytes.NewBuffer(make([]byte, 0, len(*m)<<5))
+	buf.WriteByte('{')
+
+	last := len(*m) - 1
+	for i, pair := range *m {
+		p, err := json.Marshal(pair.K)
+		if err != nil {
+			return nil, fmt.Errorf("key %q: %w", pair.K, err)
+		}
+		buf.Write(p)
+		buf.WriteByte(':')
+
+		p, err = json.Marshal(pair.V)
+		if err != nil {
+			return nil, fmt.Errorf("value of key %q: %w", pair.K, err)
+		}
+		buf.Write(p)
+
+		if i < last {
+			buf.WriteByte(',')
+		}
+	}
+
+	buf.WriteByte('}')
+	return buf.Bytes(), nil
+}
+
+// A Step is a task ran as part of a [Job].
+type Step struct {
+	// A name for the step.
+	Name string `json:"name,omitempty"`
+	// Selects an action to run as part of a step in the job.
+	Uses string `json:"uses,omitempty"`
+	// A unique identifier for the step.
+	ID string `json:"id,omitempty"`
+	// Prevent a step from running unless a condition is met.
+	If string `json:"if,omitempty"`
+	// Runs command-line programs that do not exceed 21,000 characters using the
+	// operating system's shell.
+	Run string `json:"run,omitempty"`
+	// Key-value pairs of input parameters defined by the action.
+	With Map[any] `json:"with,omitempty"`
+}
+
+// A Job is an entry in a [Workflow] document.
+type Job struct {
+	// Set a name for the job.
+	Name string `json:"name,omitempty"`
+	// Identifies any jobs that must complete successfully before this job will
+	// run.
+	Needs []string `json:"needs,omitempty"`
+	// Define the type of machine to run the job on.
+	On string `json:"runs-on,omitempty"`
+	// A sequence of tasks.
+	Steps []Step `json:"steps,omitempty"`
+}
+
+// Workflow describes a workflow document.
+type Workflow struct {
+	// The name of the workflow.
+	Name string `json:"name,omitempty"`
+	// The name for workflow runs generated from the workflow.
+	RunName string `json:"run-name,omitempty"`
+	// Define which events can cause the workflow to run.
+	On any `json:"on"`
+
+	// Named jobs part of the workflow run.
+	Jobs Map[Job] `json:"jobs,omitempty"`
+}
+
+// workflowsDir is the relative pathname of the workflows directory.
+const workflowsDir = "../../.gitea/workflows"
+
+// writeFile writes the action to the .gitea directory.
+func (w *Workflow) writeFile(name string) error {
+	f, err := os.OpenFile(
+		filepath.Join(workflowsDir, name+".yml"),
+		os.O_CREATE|os.O_EXCL|os.O_WRONLY,
+		0444,
+	)
+	if err != nil {
+		return err
+	}
+
+	err = json.NewEncoder(f).Encode(w)
+	if closeErr := f.Close(); err == nil {
+		err = closeErr
+	}
+	return err
+}
+
+// removeOnce synchronises removal of stale workflow files.
+var removeOnce sync.Once
+
+// removeWorkflows removes existing workflow files once.
+func removeWorkflows() {
+	removeOnce.Do(func() {
+		if err := os.RemoveAll(workflowsDir); err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		if err := os.Mkdir(workflowsDir, 0755); err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+	})
+}
+
+// mustWriteFile is like writeFile, but terminates the program if a non-nil
+// error is returned.
+func (w *Workflow) mustWriteFile(name string) (_ struct{}) {
+	removeWorkflows()
+
+	if err := w.writeFile(name); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	return
+}
+
+func main() {}
diff --git a/internal/workflows/release.go b/internal/workflows/release.go
new file mode 100644
index 00000000..8b7f30bb
--- /dev/null
+++ b/internal/workflows/release.go
@@ -0,0 +1,37 @@
+//go:build workflows
+
+package main
+
+var _ = (&Workflow{
+	Name: "Release",
+	On:   Map[any]{{K: "push", V: Map[string]{{K: "tags", V: "v*"}}}},
+
+	Jobs: []KV[Job]{
+		{K: "release", V: Job{
+			Name: "Create release",
+			On:   "nix",
+
+			Steps: []Step{
+				{Name: "Checkout", Uses: "actions/checkout@v4"},
+
+				{
+					Name: "Build for release",
+					Run: "nix build " +
+						"--print-out-paths " +
+						"--print-build-logs " +
+						"./test#dist",
+				},
+
+				{
+					Name: "Release",
+					Uses: "https://gitea.com/actions/release-action@main",
+
+					With: []KV[any]{
+						{K: "files", V: "result/hakurei-**"},
+						{K: "api_key", V: "${{secrets.RELEASE_TOKEN}}"},
+					},
+				},
+			},
+		}},
+	},
+}).mustWriteFile("release")
diff --git a/internal/workflows/test.go b/internal/workflows/test.go
new file mode 100644
index 00000000..1bbb04f9
--- /dev/null
+++ b/internal/workflows/test.go
@@ -0,0 +1,227 @@
+//go:build workflows
+
+package main
+
+var _ = (&Workflow{
+	Name: "Test",
+	On:   []any{"push"},
+
+	Jobs: Map[Job]{
+		{K: "hakurei", V: Job{
+			Name: "Hakurei",
+			On:   "nix",
+
+			Steps: []Step{
+				{
+					Name: "Checkout",
+					Uses: "actions/checkout@v4",
+				},
+
+				{
+					Name: "Run NixOS test",
+					Run: "nix build " +
+						"--out-link result " +
+						"--print-out-paths " +
+						"--print-build-logs " +
+						"./test#checks.x86_64-linux.hakurei",
+				},
+
+				{
+					Name: "Upload test output",
+					Uses: "actions/upload-artifact@v3",
+
+					With: Map[any]{
+						{K: "name", V: "hakurei-vm-output"},
+						{K: "path", V: "result/*"},
+
+						{K: "retention-days", V: 1},
+					},
+				},
+			},
+		}},
+
+		{K: "race", V: Job{
+			Name: "Hakurei (race detector)",
+			On:   "nix",
+
+			Steps: []Step{
+				{Name: "Checkout", Uses: "actions/checkout@v4"},
+
+				{
+					Name: "Run NixOS test",
+					Run: "nix build " +
+						"--out-link result " +
+						"--print-out-paths " +
+						"--print-build-logs " +
+						"./test#checks.x86_64-linux.race",
+				},
+
+				{
+					Name: "Upload test output",
+					Uses: "actions/upload-artifact@v3",
+
+					With: Map[any]{
+						{K: "name", V: "hakurei-race-vm-output"},
+						{K: "path", V: "result/*"},
+
+						{K: "retention-days", V: 1},
+					},
+				},
+			},
+		}},
+
+		{K: "sandbox", V: Job{
+			Name: "Sandbox",
+			On:   "nix",
+
+			Steps: []Step{
+				{Name: "Checkout", Uses: "actions/checkout@v4"},
+
+				{
+					Name: "Run NixOS test",
+					Run: "nix build " +
+						"--out-link result " +
+						"--print-out-paths " +
+						"--print-build-logs " +
+						"./test#checks.x86_64-linux.sandbox",
+				},
+
+				{
+					Name: "Upload test output",
+					Uses: "actions/upload-artifact@v3",
+
+					With: Map[any]{
+						{K: "name", V: "sandbox-vm-output"},
+						{K: "path", V: "result/*"},
+
+						{K: "retention-days", V: 1},
+					},
+				},
+			},
+		}},
+
+		{K: "sandbox-race", V: Job{
+			Name: "Sandbox (race detector)",
+			On:   "nix",
+
+			Steps: []Step{
+				{Name: "Checkout", Uses: "actions/checkout@v4"},
+
+				{
+					Name: "Run NixOS test",
+					Run: "nix build " +
+						"--out-link result " +
+						"--print-out-paths " +
+						"--print-build-logs " +
+						"./test#checks.x86_64-linux.sandbox-race",
+				},
+
+				{
+					Name: "Upload test output",
+					Uses: "actions/upload-artifact@v3",
+
+					With: Map[any]{
+						{K: "name", V: "sandbox-race-vm-output"},
+						{K: "path", V: "result/*"},
+
+						{K: "retention-days", V: 1},
+					},
+				},
+			},
+		}},
+
+		{K: "sharefs", V: Job{
+			Name: "ShareFS",
+			On:   "nix",
+
+			Steps: []Step{
+				{Name: "Checkout", Uses: "actions/checkout@v4"},
+
+				{
+					Name: "Run NixOS test",
+					Run: "nix build " +
+						"--out-link result " +
+						"--print-out-paths " +
+						"--print-build-logs " +
+						"./test#checks.x86_64-linux.sharefs",
+				},
+
+				{
+					Name: "Upload test output",
+					Uses: "actions/upload-artifact@v3",
+
+					With: Map[any]{
+						{K: "name", V: "sharefs-vm-output"},
+						{K: "path", V: "result/*"},
+
+						{K: "retention-days", V: 1},
+					},
+				},
+			},
+		}},
+
+		{K: "check", V: Job{
+			Name: "Flake checks",
+			On:   "nix",
+
+			Needs: []string{
+				"hakurei",
+				"race",
+				"sandbox",
+				"sandbox-race",
+				"sharefs",
+			},
+
+			Steps: []Step{
+				{
+					Name: "Checkout",
+					Uses: "actions/checkout@v4",
+				},
+
+				{
+					Name: "Run checks",
+					Run: "nix " +
+						"--print-build-logs " +
+						"--experimental-features 'nix-command flakes' " +
+						"flake check ./test",
+				},
+			},
+		}},
+
+		{K: "dist", V: Job{
+			Name: "Create distribution",
+			On:   "nix",
+
+			Steps: []Step{
+				{
+					Name: "Checkout",
+					Uses: "actions/checkout@v4",
+				},
+
+				{
+					Name: "Build for test",
+					ID:   "build-test",
+					Run: "export HAKUREI_REV=\"$(git rev-parse --short HEAD)\" && " +
+						"sed -i.old " +
+						"'s/version = /version = \"0.0.0-'$HAKUREI_REV'\"; # version = /' " +
+						"test/package.nix && " +
+						"nix build --print-out-paths --print-build-logs ./test#dist && " +
+						"mv test/{package.nix.old,package.nix} && " +
+						"echo \"rev=$HAKUREI_REV\" >> $GITHUB_OUTPUT",
+				},
+
+				{
+					Name: "Upload test build",
+					Uses: "actions/upload-artifact@v3",
+
+					With: Map[any]{
+						{K: "name", V: "hakurei-${{ steps.build-test.outputs.rev }}"},
+						{K: "path", V: "result/*"},
+
+						{K: "retention-days", V: 1},
+					},
+				},
+			},
+		}},
+	},
+}).mustWriteFile("test")