refactor: switch to errtrace for error stacks (#691)

[errtrace][1] includes a tool that automatically instruments error
returns to provide stack traces.

This obviates the need for us to manually wrap errors to get stacks.
Instead, we'll just use normal Go error functions (`errors.New()` and
`fmt.Errorf()` with `%w` - see docs) and automatically add the
instrumentation when building production release binaries.

[1]: https://github.com/bracesdev/errtrace

.github/workflows/release.yml

@@ -138,7 +138,8 @@ jobs:
         run: bit frontend/dist/index.html
       - name: Publish Go Binaries
         run: |
+          git ls-files -- '*.go' | xargs errtrace -w && go mod tidy
           bit build/release/ftl
-          goreleaser release
+          goreleaser release --skip=validate
         env:
           GITHUB_TOKEN: ${{ github.token }}

.golangci.yml

@@ -71,6 +71,7 @@ linters:
     - interfacebloat
     - tagalign
     - nolintlint
+    - wrapcheck # We might want to re-enable this if we manually wrap all the existing errors with fmt.Errorf
 
 linters-settings:
   exhaustive:
@@ -92,15 +93,17 @@ linters-settings:
     rules:
       main:
         deny:
-          - pkg: errors
-            desc: "use github.com/alecthomas/errors"
           - pkg: github.com/pkg/errors
-            desc: "use github.com/alecthomas/errors"
+            desc: "use fmt.Errorf or errors.New"
           - pkg: github.com/stretchr/testify
-            desc: "use alecthomas/assert"
-  wrapcheck:
-    ignorePackageGlobs:
-      - github.com/TBD54566975/ftl/*
+            desc: "use fmt.Errorf or errors.New"
+          - pkg: github.com/alecthomas/errors
+            desc: "use fmt.Errorf or errors.New"
+          - pkg: braces.dev/errtrace
+            desc: "use fmt.Errorf or errors.New"
+  # wrapcheck:
+  #   ignorePackageGlobs:
+  #     - github.com/TBD54566975/ftl/*
 
 issues:
   max-same-issues: 0

Dockerfile.controller

@@ -19,6 +19,7 @@ RUN go mod download -x
 
 # Build
 COPY . /src/
+RUN git ls-files -- '*.go' | xargs errtrace -w && go mod tidy
 RUN bit build/release/ftl-controller
 RUN bit build/release/ftl-initdb
 RUN bit build/release/ftl

Dockerfile.runner

@@ -26,6 +26,7 @@ COPY . /src/
 RUN bit build/template/ftl/jars/ftl-runtime.jar
 
 # Build runner
+RUN git ls-files -- '*.go' | xargs errtrace -w && go mod tidy
 RUN bit build/release/ftl-runner
 RUN bit build/release/ftl
 

authn/authn.go

@@ -3,6 +3,7 @@ package authn
 import (
 	"bufio"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -12,7 +13,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/alecthomas/errors"
 	"github.com/zalando/go-keyring"
 
 	"github.com/TBD54566975/ftl/backend/common/exec"
@@ -46,7 +46,7 @@ func GetAuthenticationHeaders(ctx context.Context, endpoint *url.URL, authentica
 
 	usr, err := user.Current()
 	if err != nil {
-		return nil, errors.WithStack(err)
+		return nil, err
 	}
 
 	// First, check if we have credentials in the keyring and that they work.
@@ -62,7 +62,7 @@ func GetAuthenticationHeaders(ctx context.Context, endpoint *url.URL, authentica
 	} else {
 		logger.Tracef("Credentials found in keyring: %s", creds)
 		if headers, err := checkAuth(ctx, logger, endpoint, creds); err != nil {
-			return nil, errors.WithStack(err)
+			return nil, err
 		} else if headers != nil {
 			return headers, nil
 		}
@@ -73,13 +73,13 @@ func GetAuthenticationHeaders(ctx context.Context, endpoint *url.URL, authentica
 	cmd.Stdout = out
 	err = cmd.Run()
 	if err != nil {
-		return nil, errors.Wrapf(err, "authenticator %s failed", authenticator)
+		return nil, fmt.Errorf("authenticator %s failed: %w", authenticator, err)
 	}
 
 	creds = out.String()
 	headers, err := checkAuth(ctx, logger, endpoint, creds)
 	if err != nil {
-		return nil, errors.WithStack(err)
+		return nil, err
 	} else if headers == nil {
 		return nil, nil
 	}
@@ -108,12 +108,12 @@ func checkAuth(ctx context.Context, logger *log.Logger, endpoint *url.URL, creds
 		line := buf.Text()
 		name, value, ok := strings.Cut(line, ":")
 		if !ok {
-			return nil, errors.Errorf("invalid header %q", line)
+			return nil, fmt.Errorf("invalid header %q", line)
 		}
 		headers[name] = append(headers[name], strings.TrimSpace(value))
 	}
 	if buf.Err() != nil {
-		return nil, errors.WithStack(buf.Err())
+		return nil, buf.Err()
 	}
 
 	// Issue a HEAD request with the headers to verify we get a 200 back.
@@ -125,7 +125,7 @@ func checkAuth(ctx context.Context, logger *log.Logger, endpoint *url.URL, creds
 	}
 	req, err := http.NewRequestWithContext(ctx, http.MethodHead, endpoint.String(), nil)
 	if err != nil {
-		return nil, errors.WithStack(err)
+		return nil, err
 	}
 	logger.Debugf("Authentication probe: %s %s", req.Method, req.URL)
 	for header, values := range headers {
@@ -136,7 +136,7 @@ func checkAuth(ctx context.Context, logger *log.Logger, endpoint *url.URL, creds
 	logger.Tracef("Authenticating with headers %s", headers)
 	resp, err := client.Do(req)
 	if err != nil {
-		return nil, errors.WithStack(err)
+		return nil, err
 	}
 	defer resp.Body.Close() //nolint:gosec
 	if resp.StatusCode != http.StatusOK {
@@ -177,7 +177,7 @@ func (a *authnTransport) RoundTrip(r *http.Request) (*http.Response, error) {
 		var err error
 		creds, err = GetAuthenticationHeaders(r.Context(), r.URL, a.authenticators)
 		if err != nil {
-			return nil, errors.Wrapf(err, "failed to get authentication headers for %s", r.URL.Hostname())
+			return nil, fmt.Errorf("failed to get authentication headers for %s: %w", r.URL.Hostname(), err)
 		}
 		a.lock.Lock()
 		a.credentials[r.URL.Hostname()] = creds
@@ -189,5 +189,5 @@ func (a *authnTransport) RoundTrip(r *http.Request) (*http.Response, error) {
 		}
 	}
 	resp, err := a.next.RoundTrip(r)
-	return resp, errors.WithStack(err)
+	return resp, err
 }

backend/common/bind/bind_allocator.go

@@ -7,7 +7,6 @@ import (
 	"strconv"
 
 	"github.com/alecthomas/atomic"
-	"github.com/alecthomas/errors"
 )
 
 type BindAllocator struct {
@@ -18,12 +17,12 @@ type BindAllocator struct {
 func NewBindAllocator(url *url.URL) (*BindAllocator, error) {
 	_, portStr, err := net.SplitHostPort(url.Host)
 	if err != nil {
-		return nil, errors.WithStack(err)
+		return nil, err
 	}
 
 	port, err := strconv.Atoi(portStr)
 	if err != nil {
-		return nil, errors.WithStack(err)
+		return nil, err
 	}
 
 	return &BindAllocator{

backend/common/download/download.go

@@ -2,12 +2,12 @@ package download
 
 import (
 	"context"
+	"fmt"
 	"os"
 	"path/filepath"
 	"time"
 
 	"connectrpc.com/connect"
-	"github.com/alecthomas/errors"
 
 	"github.com/TBD54566975/ftl/backend/common/log"
 	"github.com/TBD54566975/ftl/backend/common/model"
@@ -22,7 +22,7 @@ func Artefacts(ctx context.Context, client ftlv1connect.ControllerServiceClient,
 		DeploymentName: name.String(),
 	}))
 	if err != nil {
-		return errors.WithStack(err)
+		return err
 	}
 	start := time.Now()
 	count := 0
@@ -37,32 +37,32 @@ func Artefacts(ctx context.Context, client ftlv1connect.ControllerServiceClient,
 			}
 			count++
 			if !filepath.IsLocal(artefact.Path) {
-				return errors.Errorf("path %q is not local", artefact.Path)
+				return fmt.Errorf("path %q is not local", artefact.Path)
 			}
 			logger.Infof("Downloading %s", filepath.Join(dest, artefact.Path))
 			err = os.MkdirAll(filepath.Join(dest, filepath.Dir(artefact.Path)), 0700)
 			if err != nil {
-				return errors.WithStack(err)
+				return err
 			}
 			var mode os.FileMode = 0600
 			if artefact.Executable {
 				mode = 0700
 			}
 			w, err = os.OpenFile(filepath.Join(dest, artefact.Path), os.O_CREATE|os.O_WRONLY, mode)
 			if err != nil {
-				return errors.WithStack(err)
+				return err
 			}
 			digest = artefact.Digest
 		}
 
 		if _, err := w.Write(msg.Chunk); err != nil {
 			_ = w.Close()
-			return errors.WithStack(err)
+			return err
 		}
 	}
 	if w != nil {
 		w.Close()
 	}
 	logger.Infof("Downloaded %d artefacts in %s", count, time.Since(start))
-	return errors.WithStack(stream.Err())
+	return stream.Err()
 }

backend/common/exec/exec.go

@@ -6,7 +6,6 @@ import (
 	"os/exec"
 	"syscall"
 
-	"github.com/alecthomas/errors"
 	"github.com/kballard/go-shellquote"
 
 	"github.com/TBD54566975/ftl/backend/common/log"
@@ -18,15 +17,15 @@ type Cmd struct {
 
 func LookPath(exe string) (string, error) {
 	path, err := exec.LookPath(exe)
-	return path, errors.WithStack(err)
+	return path, err
 }
 
 func Capture(ctx context.Context, dir, exe string, args ...string) ([]byte, error) {
 	cmd := Command(ctx, log.Debug, dir, exe, args...)
 	cmd.Stdout = nil
 	cmd.Stderr = nil
 	out, err := cmd.CombinedOutput()
-	return out, errors.WithStack(err)
+	return out, err
 }
 
 func Command(ctx context.Context, level log.Level, dir, exe string, args ...string) *Cmd {
@@ -54,5 +53,5 @@ func (c *Cmd) Kill(signal syscall.Signal) error {
 	if c.Process == nil {
 		return nil
 	}
-	return errors.WithStack(syscall.Kill(c.Process.Pid, signal))
+	return syscall.Kill(c.Process.Pid, signal)
 }

backend/common/log/json.go

@@ -3,10 +3,9 @@ package log
 import (
 	"bufio"
 	"encoding/json"
+	"errors"
 	"io"
 	"time"
-
-	"github.com/alecthomas/errors"
 )
 
 var _ Sink = (*jsonSink)(nil)
@@ -39,7 +38,7 @@ func (j *jsonSink) Log(entry Entry) error {
 		Error: errStr,
 		Entry: entry,
 	}
-	return errors.WithStack(j.enc.Encode(jentry))
+	return j.enc.Encode(jentry)
 }
 
 // JSONStreamer reads a stream of JSON log entries from r and logs them to log.
@@ -73,5 +72,5 @@ func JSONStreamer(r io.Reader, log *Logger, defaultLevel Level) error {
 	if errors.Is(err, io.EOF) {
 		return nil
 	}
-	return errors.WithStack(err)
+	return err
 }

backend/common/log/plain.go

@@ -5,7 +5,6 @@ import (
 	"io"
 	"os"
 
-	"github.com/alecthomas/errors"
 	"github.com/mattn/go-isatty"
 )
 
@@ -51,7 +50,7 @@ func (t *plainSink) Log(entry Entry) error {
 		_, err = fmt.Fprintf(t.w, "%s%s\n", prefix, entry.Message)
 	}
 	if err != nil {
-		return errors.WithStack(err)
+		return err
 	}
 	return nil
 }

backend/common/log/tee.go

@@ -1,7 +1,7 @@
 package log
 
 import (
-	"github.com/alecthomas/errors"
+	"errors"
 )
 
 // Tee returns a sink that writes to all of the given sinks.

backend/common/model/deployment_name.go

@@ -9,7 +9,6 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/alecthomas/errors"
 	"github.com/alecthomas/types"
 )
 
@@ -37,14 +36,14 @@ func ParseDeploymentName(name string) (DeploymentName, error) {
 	var zero DeploymentName
 	parts := strings.Split(name, "-")
 	if len(parts) < 2 {
-		return zero, errors.Errorf("should be at least <deployment>-<hash>: invalid deployment name %q", name)
+		return zero, fmt.Errorf("should be at least <deployment>-<hash>: invalid deployment name %q", name)
 	}
 	hash, err := hex.DecodeString(parts[len(parts)-1])
 	if err != nil {
-		return zero, errors.Wrapf(err, "invalid deployment name %q", name)
+		return zero, fmt.Errorf("invalid deployment name %q: %w", name, err)
 	}
 	if len(hash) != 5 {
-		return zero, errors.Errorf("hash should be 5 bytes: invalid deployment name %q", name)
+		return zero, fmt.Errorf("hash should be 5 bytes: invalid deployment name %q", name)
 	}
 	return DeploymentName(fmt.Sprintf("%s-%010x", strings.Join(parts[0:len(parts)-1], "-"), hash)), nil
 }