refactor(server): Convert existing log entries to structured format

This rewrites all existing log statements into the structured logrus
format. For consistency, all errors are always logged separately from
the primary message in a field called `error`.

Only the "info", "error" and "warn" severities are used.

2 files changed, 25 insertions, 7 deletions

diff --git a/tools/nixery/server/config/config.go b/tools/nixery/server/config/config.go
index abc067855a88..9447975aa9a2 100644
--- a/tools/nixery/server/config/config.go
+++ b/tools/nixery/server/config/config.go
@@ -32,14 +32,20 @@ func signingOptsFromEnv() *storage.SignedURLOptions {
 	id := os.Getenv("GCS_SIGNING_ACCOUNT")
 
 	if path == "" || id == "" {
-		log.Println("GCS URL signing disabled")
+		log.Info("GCS URL signing disabled")
 		return nil
 	}
 
-	log.Printf("GCS URL signing enabled with account %q\n", id)
+	log.WithFields(log.Fields{
+		"account": id,
+	}).Info("GCS URL signing enabled")
+
 	k, err := ioutil.ReadFile(path)
 	if err != nil {
-		log.Fatalf("Failed to read GCS signing key: %s\n", err)
+		log.WithFields(log.Fields{
+			"file":  path,
+			"error": err,
+		}).Fatal("failed to read GCS signing key")
 	}
 
 	return &storage.SignedURLOptions{
@@ -52,7 +58,10 @@ func signingOptsFromEnv() *storage.SignedURLOptions {
 func getConfig(key, desc, def string) string {
 	value := os.Getenv(key)
 	if value == "" && def == "" {
-		log.Fatalln(desc + " must be specified")
+		log.WithFields(log.Fields{
+			"option":      key,
+			"description": desc,
+		}).Fatal("missing required configuration envvar")
 	} else if value == "" {
 		return def
 	}
diff --git a/tools/nixery/server/config/pkgsource.go b/tools/nixery/server/config/pkgsource.go
index 98719ecceabb..3a817f3d76d3 100644
--- a/tools/nixery/server/config/pkgsource.go
+++ b/tools/nixery/server/config/pkgsource.go
@@ -132,21 +132,30 @@ func (p *PkgsPath) CacheKey(pkgs []string, tag string) string {
 // specified, the Nix code will default to a recent NixOS channel.
 func pkgSourceFromEnv() (PkgSource, error) {
 	if channel := os.Getenv("NIXERY_CHANNEL"); channel != "" {
-		log.Printf("Using Nix package set from Nix channel %q\n", channel)
+		log.WithFields(log.Fields{
+			"channel": channel,
+		}).Info("using Nix package set from Nix channel or commit")
+
 		return &NixChannel{
 			channel: channel,
 		}, nil
 	}
 
 	if git := os.Getenv("NIXERY_PKGS_REPO"); git != "" {
-		log.Printf("Using Nix package set from git repository at %q\n", git)
+		log.WithFields(log.Fields{
+			"repo": git,
+		}).Info("using NIx package set from git repository")
+
 		return &GitSource{
 			repository: git,
 		}, nil
 	}
 
 	if path := os.Getenv("NIXERY_PKGS_PATH"); path != "" {
-		log.Printf("Using Nix package set from path %q\n", path)
+		log.WithFields(log.Fields{
+			"path": path,
+		}).Info("using Nix package set at local path")
+
 		return &PkgsPath{
 			path: path,
 		}, nil