Clean up error handling using new helpers from go-util

go.mod

@@ -18,7 +18,7 @@ require (
 	github.com/ulikunitz/xz v0.5.10
 	golang.org/x/crypto v0.0.0-20220622213112-05595931fe9d
 	golang.org/x/sys v0.1.0
-	zenhack.net/go/util v0.0.0-20230218002511-744d2d6d1739
+	zenhack.net/go/util v0.0.0-20230305222753-27582c3a8381
 	zenhack.net/go/vdom v0.0.0-20230302054702-c81bce9d8287
 	zenhack.net/go/websocket-capnp v0.0.0-20230212023810-f179b8b2c72b
 )

go.sum

@@ -139,6 +139,8 @@ zenhack.net/go/util v0.0.0-20230216234122-5622a28960db h1:UALBg+bDj/Xqcwg2bhc6L4
 zenhack.net/go/util v0.0.0-20230216234122-5622a28960db/go.mod h1:0lafdGg7tDb7RcXASgmJmRbLFLkAxu328+KGIs7icDE=
 zenhack.net/go/util v0.0.0-20230218002511-744d2d6d1739 h1:/QnbZBURrZUFvnxB4wDyRrPsWzh2KWbJ6AjUjohCHJ8=
 zenhack.net/go/util v0.0.0-20230218002511-744d2d6d1739/go.mod h1:0lafdGg7tDb7RcXASgmJmRbLFLkAxu328+KGIs7icDE=
+zenhack.net/go/util v0.0.0-20230305222753-27582c3a8381 h1:RMq4s41z4RoYcoWxtWfB53wjYMuid04b1ydiekJXJco=
+zenhack.net/go/util v0.0.0-20230305222753-27582c3a8381/go.mod h1:0lafdGg7tDb7RcXASgmJmRbLFLkAxu328+KGIs7icDE=
 zenhack.net/go/vdom v0.0.0-20221212051524-f5d445b862c0 h1:b47/PxX40kcz1D2glkLjSAfDAISRpytnMqOpdsAe4Rk=
 zenhack.net/go/vdom v0.0.0-20221212051524-f5d445b862c0/go.mod h1:6WIfdsOxSlWalwz8i+nMyKDjinQKQFVLDhEJGvI1dWU=
 zenhack.net/go/vdom v0.0.0-20230217005730-98b273ad5e92 h1:VfflWW9K1sz/QNzVTXUCyzlaS0pvdA5D2yq6vZoqu5E=

internal/server/main/external-api.go

@@ -8,7 +8,6 @@ import (
 	"os"
 
 	"capnproto.org/go/capnp/v3"
-	"capnproto.org/go/capnp/v3/exc"
 	"zenhack.net/go/tempest/capnp/collection"
 	"zenhack.net/go/tempest/capnp/external"
 	"zenhack.net/go/tempest/internal/config"
@@ -150,74 +149,59 @@ func newGrainID() string {
 }
 
 func (pc pkgController) Create(ctx context.Context, p external.Package_Controller_create) error {
-	args := p.Args()
-	actionIndex := args.ActionIndex()
-	title, err := args.Title()
-	if err != nil {
-		return err
-	}
-
-	actions, err := pc.pkg.Manifest.Actions()
-	if err != nil {
-		return err
-	}
-	if actionIndex >= uint32(actions.Len()) {
-		return errors.New("actionIndex out of bounds")
-	}
-	grainID := newGrainID()
-
-	tx, err := pc.server.db.Begin()
-	if err != nil {
-		return exc.WrapError("Creating database transaction", err)
-	}
-	defer tx.Rollback()
-	accountID, err := tx.GetCredentialAccount(
-		pc.userSession.Credential.Type,
-		pc.userSession.Credential.ScopedId,
-	)
-	if err != nil {
-		return exc.WrapError("Getting account ID", err)
-	}
+	return exn.Try0(func(th exn.Thrower) {
+		args := p.Args()
+		actionIndex := args.ActionIndex()
+		title, err := args.Title()
+		exn.WrapThrow(th, "getting title", err)
+
+		actions, err := pc.pkg.Manifest.Actions()
+		exn.WrapThrow(th, "getting actions", err)
+		if actionIndex >= uint32(actions.Len()) {
+			th(errors.New("actionIndex out of bounds"))
+		}
+		grainID := newGrainID()
 
-	err = os.MkdirAll(
-		config.Localstatedir+"/sandstorm/grains/"+grainID+"/sandbox",
-		0770,
-	)
-	if err != nil {
-		return exc.WrapError("Creating grain sandbox directory", err)
-	}
+		tx, err := pc.server.db.Begin()
+		exn.WrapThrow(th, "creating database transaction", err)
 
-	err = tx.AddGrain(database.NewGrain{
-		GrainId: grainID,
-		PkgId:   pc.pkg.Id,
-		Title:   title,
-		OwnerId: accountID,
+		defer tx.Rollback()
+		accountID, err := tx.GetCredentialAccount(
+			pc.userSession.Credential.Type,
+			pc.userSession.Credential.ScopedId,
+		)
+		exn.WrapThrow(th, "getting account id", err)
+
+		err = os.MkdirAll(
+			config.Localstatedir+"/sandstorm/grains/"+grainID+"/sandbox",
+			0770,
+		)
+		exn.WrapThrow(th, "creating grain sandbox directory", err)
+		err = tx.AddGrain(database.NewGrain{
+			GrainId: grainID,
+			PkgId:   pc.pkg.Id,
+			Title:   title,
+			OwnerId: accountID,
+		})
+		exn.WrapThrow(th, "creating grain in database", err)
+
+		results, err := p.AllocResults()
+		th(err)
+
+		results.SetId(grainID)
+		g, err := results.NewGrain()
+		th(err)
+		th(g.SetTitle(title))
+		// FIXME: Start the grain with the right action; as is this will just get launched w/
+		// continue when it hits the UI. Will still work for many apps.
+		sessionToken, err := session.GrainSession{
+			GrainId:   grainID,
+			SessionId: pc.userSession.SessionId,
+		}.Seal(pc.sessionStore)
+		exn.WrapThrow(th, "creating grain session token", err)
+		th(g.SetSessionToken(sessionToken))
+		// TODO: set Handle.
+		exn.WrapThrow(th, "commiting database transaction", tx.Commit())
 	})
-	if err != nil {
-		return exc.WrapError("Creating grain in database", err)
-	}
-
-	results, err := p.AllocResults()
-	if err != nil {
-		return err
-	}
-	results.SetId(grainID)
-	g, err := results.NewGrain()
-	if err != nil {
-		return err
-	}
-	g.SetTitle(title)
-	// FIXME: Start the grain with the right action; as is this will just get launched w/
-	// continue when it hits the UI. Will still work for many apps.
-	sessionToken, err := session.GrainSession{
-		GrainId:   grainID,
-		SessionId: pc.userSession.SessionId,
-	}.Seal(pc.sessionStore)
-	if err != nil {
-		return err
-	}
-	g.SetSessionToken(sessionToken)
-	// TODO: set Handle.
-	return tx.Commit()
 
 }