config: drop streaming defaults consolidated into max_message_bytes

Removes _defaultMaxNumTargets/_defaultMaxNumChangedTargets/_defaultMaxNumMetadataEntries
and their Parse defaulting blocks — they no longer match config/README.md
(which documents a single max_message_bytes) and are about to be deleted
outright by the follow-up PR that lands the consolidation, so there's no
reason to introduce them here first.

Also answers a review question on why _bzlmodEnabledDefault sits outside
the const block: it has to be a var so its address can be taken.

Author: yushan8

config/config.go

@@ -22,16 +22,12 @@ import (
 	yaml "github.com/goccy/go-yaml"
 )
 
-const (
-	_defaultBazelQueryTimeoutSeconds = 600
-	_defaultMaxNumTargets            = 250
-	_defaultMaxNumChangedTargets     = 125
-	_defaultMaxNumMetadataEntries    = 50_000
-)
+const _defaultBazelQueryTimeoutSeconds = 600
 
-var (
-	_bzlmodEnabledDefault = true
-)
+// _bzlmodEnabledDefault backs RepositoryConfig.BzlmodEnabled's default. It must
+// be a var, not a const, so its address can be taken below — *bool is how
+// BzlmodEnabled distinguishes "unset" from "explicitly false".
+var _bzlmodEnabledDefault = true
 
 var _ RepositoryConfigProvider = (*Config)(nil)
 
@@ -78,15 +74,6 @@ func Parse(configFilePath string) (*Config, error) {
 	if config.Service.MaxWorkerPoolSize <= 0 {
 		return nil, fmt.Errorf("service.max_worker_pool_size must be > 0, got %d", config.Service.MaxWorkerPoolSize)
 	}
-	if config.Service.Streaming.MaxNumTargets <= 0 {
-		config.Service.Streaming.MaxNumTargets = _defaultMaxNumTargets
-	}
-	if config.Service.Streaming.MaxNumChangedTargets <= 0 {
-		config.Service.Streaming.MaxNumChangedTargets = _defaultMaxNumChangedTargets
-	}
-	if config.Service.Streaming.MaxNumMetadataEntries <= 0 {
-		config.Service.Streaming.MaxNumMetadataEntries = _defaultMaxNumMetadataEntries
-	}
 	config.repositoryByRemote = make(map[string]*RepositoryConfig, len(config.Repository))
 	for i := range config.Repository {
 		remote := config.Repository[i].Remote

config/config_test.go

@@ -72,23 +72,17 @@ repository:
 
 func TestParse_ServiceDefaults(t *testing.T) {
 	tests := []struct {
-		name                      string
-		give                      string
-		wantWorkerRootPath        string
-		wantMaxNumTargets         int
-		wantMaxNumChangedTargets  int
-		wantMaxNumMetadataEntries int
+		name               string
+		give               string
+		wantWorkerRootPath string
 	}{
 		{
-			name: "worker_root_path and streaming default when unset",
+			name: "worker_root_path defaults when unset",
 			give: _baseServiceYAML + `
 repository:
   - remote: "r1"
 `,
-			wantWorkerRootPath:        filepath.Join("/tmp/x", ".workers"),
-			wantMaxNumTargets:         _defaultMaxNumTargets,
-			wantMaxNumChangedTargets:  _defaultMaxNumChangedTargets,
-			wantMaxNumMetadataEntries: _defaultMaxNumMetadataEntries,
+			wantWorkerRootPath: filepath.Join("/tmp/x", ".workers"),
 		},
 		{
 			name: "worker_root_path explicit value preserved",
@@ -100,25 +94,7 @@ service:
 repository:
   - remote: "r1"
 `,
-			wantWorkerRootPath:        "/tmp/custom-workers",
-			wantMaxNumTargets:         _defaultMaxNumTargets,
-			wantMaxNumChangedTargets:  _defaultMaxNumChangedTargets,
-			wantMaxNumMetadataEntries: _defaultMaxNumMetadataEntries,
-		},
-		{
-			name: "streaming explicit values preserved",
-			give: _baseServiceYAML + `
-  streaming:
-    max_num_targets: 10
-    max_num_changed_targets: 20
-    max_num_metadata_entries: 30
-repository:
-  - remote: "r1"
-`,
-			wantWorkerRootPath:        filepath.Join("/tmp/x", ".workers"),
-			wantMaxNumTargets:         10,
-			wantMaxNumChangedTargets:  20,
-			wantMaxNumMetadataEntries: 30,
+			wantWorkerRootPath: "/tmp/custom-workers",
 		},
 	}
 
@@ -127,9 +103,6 @@ repository:
 			cfg, err := Parse(writeConfig(t, tt.give))
 			require.NoError(t, err)
 			assert.Equal(t, tt.wantWorkerRootPath, cfg.Service.WorkerRootPath)
-			assert.Equal(t, tt.wantMaxNumTargets, cfg.Service.Streaming.MaxNumTargets)
-			assert.Equal(t, tt.wantMaxNumChangedTargets, cfg.Service.Streaming.MaxNumChangedTargets)
-			assert.Equal(t, tt.wantMaxNumMetadataEntries, cfg.Service.Streaming.MaxNumMetadataEntries)
 		})
 	}
 }