Files
github--github-mcp-server/pkg/github/feature_flags.go
T
2026-07-13 12:37:57 +08:00

94 lines
3.8 KiB
Go

package github
import "slices"
// MCPAppsFeatureFlag is the feature flag name for MCP Apps (interactive UI forms).
const MCPAppsFeatureFlag = "remote_mcp_ui_apps"
// FeatureFlagCSVOutput is the feature flag name for CSV output on list tools.
const FeatureFlagCSVOutput = "csv_output"
// FeatureFlagIFCLabels is the feature flag name for IFC security labels in tool results.
const FeatureFlagIFCLabels = "ifc_labels"
// FeatureFlagFileBlame is the feature flag name for the get_file_blame tool,
// which exposes git blame information for a file. It is gated so the extra tool
// is not advertised by default, keeping the tool surface small unless opted in.
const FeatureFlagFileBlame = "file_blame"
// FeatureFlagIssueDependencies is the feature flag name for the issue dependency
// tools (issue_dependency_read / issue_dependency_write), which read and edit an
// issue's blocked-by / blocking relationships. It is gated so these tools are not
// advertised in the default surface, keeping the fixed tool-schema cost small
// unless explicitly opted in.
const FeatureFlagIssueDependencies = "issue_dependencies"
// FeatureFlagFieldsParam is the feature flag name for the optional `fields`
// parameter on selected read tools (for example search_code and
// get_file_contents). When enabled, those tools advertise `fields` and filter
// each result to the requested subset, reducing response size. It is gated so
// the feature can be rolled out gradually and disabled as a kill switch without
// a redeploy.
const FeatureFlagFieldsParam = "fields_param"
// AllowedFeatureFlags is the allowlist of feature flags that can be enabled
// by users via --features CLI flag or X-MCP-Features HTTP header.
// Only flags in this list are accepted; unknown flags are silently ignored.
// This is the single source of truth for which flags are user-controllable.
var AllowedFeatureFlags = []string{
MCPAppsFeatureFlag,
FeatureFlagCSVOutput,
FeatureFlagIFCLabels,
FeatureFlagIssuesGranular,
FeatureFlagPullRequestsGranular,
FeatureFlagFileBlame,
FeatureFlagIssueDependencies,
FeatureFlagFieldsParam,
}
// InsidersFeatureFlags is the list of feature flags that insiders mode enables.
// When insiders mode is active, all flags in this list are treated as enabled.
// This is the single source of truth for what "insiders" means in terms of
// feature flag expansion.
var InsidersFeatureFlags = []string{
MCPAppsFeatureFlag,
FeatureFlagCSVOutput,
FeatureFlagFileBlame,
FeatureFlagIssueDependencies,
}
// FeatureFlags defines runtime feature toggles that adjust tool behavior.
type FeatureFlags struct {
LockdownMode bool
}
// ResolveFeatureFlags computes the effective set of enabled feature flags by:
// 1. Taking the user-supplied flags (from --features or X-MCP-Features) and
// keeping only those present in AllowedFeatureFlags. Unknown or unsafe
// flags from request input are silently dropped here.
// 2. If insiders mode is on, unioning in every flag from InsidersFeatureFlags.
// Insiders is a server-controlled meta switch, so its expansion is NOT
// re-validated against AllowedFeatureFlags.
//
// AllowedFeatureFlags and InsidersFeatureFlags are independent sets:
// - A flag in AllowedFeatureFlags but not InsidersFeatureFlags is a regular
// opt-in flag that insiders mode does not turn on automatically.
// - A flag in InsidersFeatureFlags but not AllowedFeatureFlags is reachable
// only through insiders mode and cannot be enabled by user input.
//
// Returns a set (map) for O(1) lookup by the feature checker.
func ResolveFeatureFlags(enabledFeatures []string, insidersMode bool) map[string]bool {
effective := make(map[string]bool)
for _, f := range enabledFeatures {
if slices.Contains(AllowedFeatureFlags, f) {
effective[f] = true
}
}
if insidersMode {
for _, f := range InsidersFeatureFlags {
effective[f] = true
}
}
return effective
}