fix(plugins): stop the TypeScript telemetry losing events and misattributing accounts (#7358)

integrations/opencode-plugin/telemetry.ts

@@ -25,7 +25,9 @@ const PLUGIN_VERSION = (() => {
 let currentDistinctId = "";
 const telemetry = createTelemetry({
   host: "opencode",
-  source: "plugin",
+  // Shaped like the platform's EventSource values, as every other surface is.
+  // "plugin" said nothing about which plugin and matched no vocabulary.
+  source: "OPENCODE_PLUGIN",
   version: PLUGIN_VERSION,
   distinctId: () => currentDistinctId,
   eventName: (event) => `plugin.${event}`,
@@ -40,8 +42,23 @@ function distinctId(apiKey: string): string {
   return createHash("sha256").update(apiKey).digest("hex").slice(0, 32);
 }
 
-function projectHash(projectId?: string): Record<string, string> {
-  return projectId ? { project_hash: createHash("sha256").update(projectId).digest("hex") } : {};
+/**
+ * Salted so the hash is not enumerable.
+ *
+ * An unsalted SHA-256 of a project id is reversible by anyone who can guess the
+ * id, which for a project identifier is a small space. The API key is the salt:
+ * it is already in play here (distinctId is a digest of it), it is high entropy,
+ * and using it needs no per-install file and so no write race to get wrong. The
+ * hash is therefore per account rather than per machine, which also keeps joins
+ * working for one user across machines. It resets when the key rotates, which is
+ * consistent, because distinctId resets with it.
+ *
+ * Both are omitted without a key. An event cannot be built without a distinctId
+ * anyway, so this costs nothing.
+ */
+function projectHash(projectId?: string, apiKey?: string): Record<string, string> {
+  if (!projectId || !apiKey) return {};
+  return { project_hash: createHash("sha256").update(`${apiKey}:${projectId}`).digest("hex") };
 }
 
 export function buildEvent(
@@ -51,7 +68,7 @@ export function buildEvent(
   projectId?: string,
 ): Record<string, unknown> | null {
   currentDistinctId = apiKey ? distinctId(apiKey) : "";
-  const event = telemetry.build(eventType, { ...properties, ...projectHash(projectId) });
+  const event = telemetry.build(eventType, { ...properties, ...projectHash(projectId, apiKey) });
   return event ? { api_key: POSTHOG_API_KEY, ...event } : null;
 }
 
@@ -62,5 +79,5 @@ export function captureEvent(
   projectId?: string,
 ): void {
   currentDistinctId = apiKey ? distinctId(apiKey) : "";
-  telemetry.capture(eventType, { ...properties, ...projectHash(projectId) });
+  telemetry.capture(eventType, { ...properties, ...projectHash(projectId, apiKey) });
 }