WALRecevier read password from env var

primary_conninfo string is too long when the token is included.

Wal receiver reads the password from NEON_AUTH_TOKEN instead.

Author: HaoyuHuang

src/backend/replication/libpqwalreceiver/libpqwalreceiver.c

@@ -147,8 +147,11 @@ libpqrcv_connect(const char *conninfo, bool replication, bool logical,
 				 bool must_use_password, const char *appname, char **err)
 {
 	WalReceiverConn *conn;
-	const char *keys[6];
-	const char *vals[6];
+/* BEGIN_NEON */
+	const char *keys[7];
+	const char *vals[7];
+	char * neon_auth_token = NULL;
+/* END_NEON */
 	int			i = 0;
 
 	/*
@@ -206,6 +209,23 @@ libpqrcv_connect(const char *conninfo, bool replication, bool logical,
 	keys[++i] = "fallback_application_name";
 	vals[i] = appname;
 
+/* BEGIN_NEON */
+	if (pg_strcasecmp(appname, "walreceiver") == 0)
+	{
+		neon_auth_token = getenv("NEON_AUTH_TOKEN");
+		if (neon_auth_token != NULL)
+		{
+			elog(LOG, "Use NEON_AUTH_TOKEN to connect");
+			keys[++i] = "password";
+			vals[i] = neon_auth_token;
+		}
+		else
+		{
+			elog(LOG, "NEON_AUTH_TOKEN is undefined in the environment");
+		}
+	}
+/* END_NEON */
+
 	keys[++i] = NULL;
 	vals[i] = NULL;