Allow selecting a backend for specific services.

yext · Mar 18, 2018 · 0482f1f · 0482f1f
1 parent 07713cf
commit 0482f1f
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Showing 14 changed files with 71 additions and 26 deletions.
diff --git a/builder/build.go b/builder/build.go
@@ -59,7 +59,7 @@ func (b *builder) BuildWithTracker(dirConfig *home.EdwardConfiguration, task tra
 		return errors.WithStack(err)
 	}
 
-	builder, err := services.GetBuilder(service)
+	builder, err := services.GetBuilder(b.Cfg, service)
 	if err != nil {
 		return errors.WithStack(err)
 	}

diff --git a/cmd/root.go b/cmd/root.go
@@ -6,6 +6,7 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"strings"
 
 	lumberjack "gopkg.in/natefinch/lumberjack.v2"
 
@@ -115,6 +116,10 @@ Build, start and manage service instances with a single command.`,
 		}
 
 		edwardClient.DirConfig = dirConfig
+		edwardClient.Backends, err = buildBackendOverrides()
+		if err != nil {
+			return errors.WithStack(err)
+		}
 
 		// Set service checks to restart the client on sudo as needed
 		edwardClient.ServiceChecks = func(sgs []services.ServiceOrGroup) error {
@@ -158,6 +163,21 @@ Build, start and manage service instances with a single command.`,
 	},
 }
 
+func buildBackendOverrides() (map[string]string, error) {
+	var overrides = make(map[string]string)
+	for _, backend := range backends {
+		separated := strings.Split(backend, ":")
+		if len(separated) != 2 {
+			return nil, errors.New("backend definition should be of the form '<service>:<backend>'")
+		}
+		if _, exists := overrides[separated[0]]; exists {
+			return nil, fmt.Errorf("multiple backend selections specified for service or group: %s", separated[0])
+		}
+		overrides[separated[0]] = separated[1]
+	}
+	return overrides, nil
+}
+
 // Execute adds all child commands to the root command and sets flags appropriately.
 // This is called by main.main(). It only needs to happen once to the rootCmd.
 func Execute() {
@@ -197,6 +217,7 @@ var configPath string
 var redirectLogs bool
 var logFile string
 var edwardHome string
+var backends []string
 
 func init() {
 	cobra.OnInitialize(initConfig)
@@ -205,6 +226,7 @@ func init() {
 	RootCmd.PersistentFlags().StringVarP(&configPath, "config", "c", "", "Use service configuration file at `PATH`")
 	RootCmd.PersistentFlags().BoolVar(&redirectLogs, "redirect_logs", false, "Redirect edward logs to the console")
 	RootCmd.PersistentFlags().StringVar(&edwardHome, "edward_home", "", "")
+	RootCmd.PersistentFlags().StringSliceVarP(&backends, "backend", "b", nil, "Choose a specific backend for a service or group, of the form '<service>:<backend name>'")
 	err := RootCmd.PersistentFlags().MarkHidden("redirect_logs")
 	if err != nil {
 		panic(err)

diff --git a/cmd/run.go b/cmd/run.go
@@ -6,6 +6,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 	"github.com/yext/edward/runner"
+	"github.com/yext/edward/services"
 )
 
 // runCmd represents the run command
@@ -17,7 +18,15 @@ var runCmd = &cobra.Command{
 		if service == nil {
 			return fmt.Errorf("service not found: %s", args[0])
 		}
+		c := edwardClient
 		r, err := runner.NewRunner(
+			services.OperationConfig{
+				WorkingDir:       c.WorkingDir,
+				EdwardExecutable: c.EdwardExecutable,
+				Tags:             c.Tags,
+				LogFile:          c.LogFile,
+				Backends:         c.Backends,
+			},
 			service,
 			edwardClient.DirConfig,
 			*runFlags.noWatch,

diff --git a/edward/client.go b/edward/client.go
@@ -47,6 +47,8 @@ type Client struct {
 	Tags []string // Tags to distinguish runners started by this instance of edward
 
 	DirConfig *home.EdwardConfiguration
+
+	Backends map[string]string // Service overrides for backends
 }
 
 type TaskFollower interface {
@@ -122,6 +124,7 @@ func (c *Client) startAndTrack(sgs []services.ServiceOrGroup, skipBuild bool, no
 		NoWatch:          noWatch,
 		Tags:             c.Tags,
 		LogFile:          c.LogFile,
+		Backends:         c.Backends,
 	}
 
 	task := tracker.NewTask(c.Follower.Handle)

diff --git a/edward/restart.go b/edward/restart.go
@@ -78,6 +78,7 @@ func (c *Client) restartOneOrMoreServices(serviceNames []string, skipBuild bool,
 		NoWatch:          noWatch,
 		Tags:             c.Tags,
 		LogFile:          c.LogFile,
+		Backends:         c.Backends,
 	}
 
 	task := tracker.NewTask(c.Follower.Handle)

diff --git a/edward/stop.go b/edward/stop.go
@@ -29,6 +29,7 @@ func (c *Client) Stop(names []string, force bool, exclude []string, all bool) er
 		Exclusions:       exclude,
 		Tags:             c.Tags,
 		LogFile:          c.LogFile,
+		Backends:         c.Backends,
 	}
 
 	task := tracker.NewTask(c.Follower.Handle)

diff --git a/runner/runner.go b/runner/runner.go
@@ -39,6 +39,7 @@ type Runner struct {
 }
 
 func NewRunner(
+	cfg services.OperationConfig,
 	service *services.ServiceConfig,
 	dirConfig *home.EdwardConfiguration,
 	noWatch bool,
@@ -53,7 +54,7 @@ func NewRunner(
 		Logger:     logger,
 	}
 	var err error
-	r.backendRunner, err = services.GetRunner(service)
+	r.backendRunner, err = services.GetRunner(cfg, service)
 	if err != nil {
 		return nil, errors.WithStack(err)
 	}

diff --git a/services/backends.go b/services/backends.go
@@ -16,8 +16,8 @@ type BackendLoader interface {
 	New() Backend
 	Name() string
 	Handles(Backend) bool
-	Builder(*ServiceConfig) (Builder, error)
-	Runner(*ServiceConfig) (Runner, error)
+	Builder(*ServiceConfig, Backend) (Builder, error)
+	Runner(*ServiceConfig, Backend) (Runner, error)
 }
 
 type Runner interface {
@@ -43,19 +43,24 @@ func RegisterBackend(loader BackendLoader) {
 	loaders[loader.Name()] = loader
 }
 
-func GetBuilder(s *ServiceConfig) (Builder, error) {
+func GetBuilder(cfg OperationConfig, s *ServiceConfig) (Builder, error) {
+	expectedBackend := cfg.Backends[s.Name]
 	for _, backend := range s.Backends {
+		if expectedBackend != "" && backend.Name != expectedBackend {
+			continue
+		}
 		if loader, ok := loaders[backend.Type]; ok {
-			return loader.Builder(s)
+			// TODO: we need to be able to pass in the backend config
+			return loader.Builder(s, backend.Config)
 		}
 	}
 	return nil, fmt.Errorf("builder not found for service '%s'", s.Name)
 }
 
-func GetRunner(s *ServiceConfig) (Runner, error) {
+func GetRunner(cfg OperationConfig, s *ServiceConfig) (Runner, error) {
 	for _, backend := range s.Backends {
 		if loader, ok := loaders[backend.Type]; ok {
-			return loader.Runner(s)
+			return loader.Runner(s, backend.Config)
 		}
 	}
 	return nil, fmt.Errorf("runner not found for service '%s'", s.Name)

diff --git a/services/backends/commandline/buildandrun_test.go b/services/backends/commandline/buildandrun_test.go
@@ -76,7 +76,7 @@ func TestStartService(t *testing.T) {
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
-			runner, err := services.GetRunner(test.service)
+			runner, err := services.GetRunner(services.OperationConfig{}, test.service)
 			if err != nil {
 				t.Error(err)
 				return
@@ -196,7 +196,7 @@ func TestStartServiceFailure(t *testing.T) {
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
-			runner, err := services.GetRunner(test.service)
+			runner, err := services.GetRunner(services.OperationConfig{}, test.service)
 			if err != nil {
 				t.Error(err)
 				return

diff --git a/services/backends/commandline/loader.go b/services/backends/commandline/loader.go
@@ -21,16 +21,16 @@ func (l *Loader) Handles(c services.Backend) bool {
 	return ok
 }
 
-func (l *Loader) Builder(s *services.ServiceConfig) (services.Builder, error) {
-	return l.buildandrun(s)
+func (l *Loader) Builder(s *services.ServiceConfig, b services.Backend) (services.Builder, error) {
+	return l.buildandrun(s, b)
 }
 
-func (l *Loader) Runner(s *services.ServiceConfig) (services.Runner, error) {
-	return l.buildandrun(s)
+func (l *Loader) Runner(s *services.ServiceConfig, b services.Backend) (services.Runner, error) {
+	return l.buildandrun(s, b)
 }
 
-func (l *Loader) buildandrun(s *services.ServiceConfig) (*buildandrun, error) {
-	if config, ok := s.Backend().(*Backend); ok {
+func (l *Loader) buildandrun(s *services.ServiceConfig, b services.Backend) (*buildandrun, error) {
+	if config, ok := b.(*Backend); ok {
 		return &buildandrun{
 			Service: s,
 			Backend: config,

diff --git a/services/backends/docker/buildandrun_test.go b/services/backends/docker/buildandrun_test.go
@@ -56,7 +56,7 @@ func TestBuild(t *testing.T) {
 			},
 		},
 	}
-	b, err := services.GetBuilder(service)
+	b, err := services.GetBuilder(services.OperationConfig{}, service)
 	if err != nil {
 		t.Error(err)
 		return
@@ -102,7 +102,7 @@ func TestStart(t *testing.T) {
 }
 
 func doStartTest(t *testing.T, service *services.ServiceConfig) {
-	b, err := services.GetRunner(service)
+	b, err := services.GetRunner(services.OperationConfig{}, service)
 	if err != nil {
 		t.Error(err)
 		return

diff --git a/services/backends/docker/loader.go b/services/backends/docker/loader.go
@@ -22,20 +22,20 @@ func (l *Loader) Handles(c services.Backend) bool {
 	return ok
 }
 
-func (l *Loader) Builder(s *services.ServiceConfig) (services.Builder, error) {
-	return l.buildandrun(s)
+func (l *Loader) Builder(s *services.ServiceConfig, backend services.Backend) (services.Builder, error) {
+	return l.buildandrun(s, backend)
 }
 
-func (l *Loader) Runner(s *services.ServiceConfig) (services.Runner, error) {
-	return l.buildandrun(s)
+func (l *Loader) Runner(s *services.ServiceConfig, backend services.Backend) (services.Runner, error) {
+	return l.buildandrun(s, backend)
 }
 
-func (l *Loader) buildandrun(s *services.ServiceConfig) (*buildandrun, error) {
+func (l *Loader) buildandrun(s *services.ServiceConfig, backend services.Backend) (*buildandrun, error) {
 	client, err := client.NewEnvClient()
 	if err != nil {
 		return nil, errors.WithMessage(err, "initializing client")
 	}
-	if config, ok := s.Backend().(*Backend); ok {
+	if config, ok := backend.(*Backend); ok {
 		return &buildandrun{
 			Service: s,
 			Backend: config,

diff --git a/services/backends_test.go b/services/backends_test.go
@@ -18,10 +18,12 @@ type loaderProto struct {
 func (l *loaderProto) New() services.Backend           { return l.new() }
 func (l *loaderProto) Name() string                    { return l.name }
 func (l *loaderProto) Handles(c services.Backend) bool { return l.handles(c) }
-func (l *loaderProto) Builder(s *services.ServiceConfig) (services.Builder, error) {
+func (l *loaderProto) Builder(s *services.ServiceConfig, b services.Backend) (services.Builder, error) {
 	return l.builder(s)
 }
-func (l *loaderProto) Runner(s *services.ServiceConfig) (services.Runner, error) { return l.runner(s) }
+func (l *loaderProto) Runner(s *services.ServiceConfig, b services.Backend) (services.Runner, error) {
+	return l.runner(s)
+}
 
 type configTest struct {
 	Field string `json:"field"`

diff --git a/services/services.go b/services/services.go
@@ -15,6 +15,7 @@ type OperationConfig struct {
 	SkipBuild        bool
 	Tags             []string // Tags to pass to `edward run`
 	LogFile          string
+	Backends         map[string]string // Service overrides for backends
 }
 
 // IsExcluded returns true if the given service/group is excluded by this OperationConfig.