Introduce serve command

See #53.

Author: edigaryev

internal/commands/root.go

@@ -37,6 +37,7 @@ func NewRootCmd() *cobra.Command {
 	cmd.AddCommand(
 		newValidateCmd(),
 		newRunCmd(),
+		newServeCmd(),
 	)
 
 	return cmd

internal/commands/serve.go

@@ -0,0 +1,44 @@
+package commands
+
+import (
+	"errors"
+	"fmt"
+	"github.com/cirruslabs/cirrus-cli/internal/evaluator"
+	"github.com/spf13/cobra"
+	"net"
+)
+
+var ErrServe = errors.New("serve failed")
+
+var address string
+
+func serve(cmd *cobra.Command, args []string) error {
+	// https://github.com/spf13/cobra/issues/340#issuecomment-374617413
+	cmd.SilenceUsage = true
+
+	lis, err := net.Listen("tcp", address)
+	if err != nil {
+		return fmt.Errorf("%w: %v", ErrServe, err)
+	}
+
+	fmt.Printf("listening on %s\n", lis.Addr().String())
+
+	if err := evaluator.Serve(cmd.Context(), lis); err != nil {
+		return fmt.Errorf("%w: %v", ErrServe, err)
+	}
+
+	return nil
+}
+
+func newServeCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:    "serve [flags]",
+		Short:  "Run RPC server that evaluates YAML and Starlark configurations",
+		RunE:   serve,
+		Hidden: true,
+	}
+
+	cmd.PersistentFlags().StringVarP(&address, "listen", "l", ":8080", "address to listen on")
+
+	return cmd
+}

internal/evaluator/evaluator.go

@@ -0,0 +1,78 @@
+package evaluator
+
+import (
+	"context"
+	"github.com/cirruslabs/cirrus-ci-agent/api"
+	"github.com/cirruslabs/cirrus-cli/pkg/larker"
+	"github.com/cirruslabs/cirrus-cli/pkg/parser"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+	"net"
+	"strings"
+)
+
+func Serve(ctx context.Context, lis net.Listener) error {
+	server := grpc.NewServer()
+
+	api.RegisterCirrusConfigurationEvaluatorServiceService(server, &api.CirrusConfigurationEvaluatorServiceService{
+		EvaluateConfig: evaluateConfig,
+	})
+
+	errChan := make(chan error)
+
+	go func() {
+		errChan <- server.Serve(lis)
+	}()
+
+	select {
+	case <-ctx.Done():
+		server.GracefulStop()
+
+		if err := <-errChan; err != nil {
+			return err
+		}
+
+		return ctx.Err()
+	case err := <-errChan:
+		return err
+	}
+}
+
+func evaluateConfig(ctx context.Context, request *api.EvaluateConfigRequest) (*api.EvaluateConfigResponse, error) {
+	var yamlConfigs []string
+
+	// Register YAML configuration (if any)
+	if request.YamlConfig != "" {
+		yamlConfigs = append(yamlConfigs, request.YamlConfig)
+	}
+
+	// Run Starlark script and register generated YAML configuration (if any)
+	if request.StarlarkConfig != "" {
+		lrk := larker.New(larker.WithEnvironment(request.Environment))
+
+		generatedYamlConfig, err := lrk.Main(ctx, request.StarlarkConfig)
+		if err != nil {
+			return nil, status.Error(codes.InvalidArgument, err.Error())
+		}
+
+		yamlConfigs = append(yamlConfigs, generatedYamlConfig)
+	}
+
+	// Parse combined YAML
+	p := parser.New(
+		parser.WithEnvironment(request.Environment),
+		parser.WithFilesContents(request.FilesContents),
+	)
+
+	result, err := p.Parse(strings.Join(yamlConfigs, "\n"))
+	if err != nil {
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	}
+
+	if len(result.Errors) != 0 {
+		return nil, status.Error(codes.InvalidArgument, result.Errors[0])
+	}
+
+	return &api.EvaluateConfigResponse{Tasks: result.Tasks}, nil
+}

internal/evaluator/evaluator_test.go

@@ -0,0 +1,90 @@
+package evaluator_test
+
+import (
+	"context"
+	"errors"
+	"github.com/cirruslabs/cirrus-ci-agent/api"
+	"github.com/cirruslabs/cirrus-cli/internal/evaluator"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc"
+	"net"
+	"testing"
+)
+
+func evaluateHelper(t *testing.T, request *api.EvaluateConfigRequest) (*api.EvaluateConfigResponse, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+
+	lis, err := net.Listen("tcp", "localhost:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	errChan := make(chan error)
+
+	go func() {
+		errChan <- evaluator.Serve(ctx, lis)
+	}()
+
+	defer func() {
+		cancel()
+
+		if err := <-errChan; err != nil && !errors.Is(err, context.Canceled) {
+			t.Fatal(err)
+		}
+	}()
+
+	conn, err := grpc.Dial(lis.Addr().String(), grpc.WithInsecure())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	client := api.NewCirrusConfigurationEvaluatorServiceClient(conn)
+
+	response, err := client.EvaluateConfig(context.Background(), request)
+	if err != nil {
+		return nil, err
+	}
+
+	return response, nil
+}
+
+// TestCrossDependencies ensures that tasks declared in YAML and generated from Starlark can reference each other.
+func TestCrossDependencies(t *testing.T) {
+	yamlConfig := `
+container:
+  image: debian:latest
+
+task:
+  name: Black
+  depends_on:
+    - White
+  script: true
+
+task:
+  name: Green
+  script: true
+`
+
+	starlarkConfig := `
+def main(ctx):
+    return [
+        {
+            "name": "White",
+            "script": "true",
+        },
+        {
+            "name": "Yellow",
+            "depends_on": [
+                "Green",
+            ],
+            "script": "true",
+        }
+    ]
+`
+
+	_, err := evaluateHelper(t, &api.EvaluateConfigRequest{
+		YamlConfig:     yamlConfig,
+		StarlarkConfig: starlarkConfig,
+	})
+	require.NoError(t, err)
+}