From be1a39b03b00575d2eedcbd501d09b925029397d Mon Sep 17 00:00:00 2001 From: Steffen Vogel Date: Wed, 28 Mar 2018 14:13:13 +0200 Subject: [PATCH] hook: added new hook for rate limiting --- lib/hooks/Makefile.inc | 2 +- lib/hooks/limit_rate.c | 140 +++++++++++++++++++++++++++ tests/integration/hook-limit_rate.sh | 41 ++++++++ 3 files changed, 182 insertions(+), 1 deletion(-) create mode 100644 lib/hooks/limit_rate.c create mode 100755 tests/integration/hook-limit_rate.sh diff --git a/lib/hooks/Makefile.inc b/lib/hooks/Makefile.inc index b81ac2a4a..586dd592e 100644 --- a/lib/hooks/Makefile.inc +++ b/lib/hooks/Makefile.inc @@ -22,7 +22,7 @@ LIB_SRCS += $(addprefix lib/hooks/, convert.c decimate.c drop.c jitter_calc.c \ map.c restart.c shift_seq.c shift_ts.c \ - skip_first.c stats.c ts.c) + skip_first.c stats.c ts.c limit_rate.c) ifeq ($(WITH_IO),1) LIB_SRCS += lib/hooks/print.c diff --git a/lib/hooks/limit_rate.c b/lib/hooks/limit_rate.c new file mode 100644 index 000000000..04e1f9f24 --- /dev/null +++ b/lib/hooks/limit_rate.c @@ -0,0 +1,140 @@ +/** Rate-limiting hook. + * + * @author Steffen Vogel + * @copyright 2017, Institute for Automation of Complex Power Systems, EONERC + * @license GNU General Public License (version 3) + * + * VILLASnode + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + *********************************************************************************/ + +/** @addtogroup hooks Hook functions + * @{ + */ + +#include + +#include "villas/hook.h" +#include "villas/plugin.h" +#include "villas/timing.h" +#include "villas/sample.h" + +struct limit_rate { + enum { + LIMIT_RATE_LOCAL, + LIMIT_RATE_RECEIVED, + LIMIT_RATE_ORIGIN + } mode; /**< The timestamp which should be used for limiting. */ + + double deadtime; + struct timespec last; +}; + +static int limit_rate_init(struct hook *h) +{ + struct limit_rate *p = (struct limit_rate *) h->_vd; + + p->last = (struct timespec) { 0 }; + + /* Default values */ + p->mode = LIMIT_RATE_LOCAL; + + return 0; +} + +static int limit_rate_parse(struct hook *h, json_t *cfg) +{ + struct limit_rate *p = (struct limit_rate *) h->_vd; + + int ret; + json_error_t err; + + double rate; + const char *mode = NULL; + + ret = json_unpack_ex(cfg, &err, 0, "{ s: F, s?: s }", + "rate", &rate, + "mode", &mode + ); + if (ret) + jerror(&err, "Failed to parse configuration of hook '%s'", plugin_name(h->_vt)); + + if (mode) { + if (!strcmp(mode, "origin")) + p->mode = LIMIT_RATE_ORIGIN; + else if (!strcmp(mode, "received")) + p->mode = LIMIT_RATE_RECEIVED; + else if (!strcmp(mode, "local")) + p->mode = LIMIT_RATE_LOCAL; + else + error("Invalid value '%s' for setting 'mode' in limit_rate hook", mode); + } + + p->deadtime = 1.0 / rate; + + return 0; +} + +static int limit_rate_write(struct hook *h, struct sample *smps[], unsigned *cnt) +{ + struct limit_rate *p = (struct limit_rate *) h->_vd; + + struct timespec next; + unsigned ret = 0; + + for (unsigned i = 0; i < *cnt; i++) { + switch (p->mode) { + case LIMIT_RATE_LOCAL: + next = time_now(); + break; + + case LIMIT_RATE_ORIGIN: + next = smps[i]->ts.origin; + break; + + case LIMIT_RATE_RECEIVED: + next = smps[i]->ts.received; + break; + } + + if (time_delta(&p->last, &next) < p->deadtime) + continue; /* Drop this sample */ + + p->last = next; + smps[ret++] = smps[i]; + } + + *cnt = ret; + + return 0; +} + +static struct plugin p = { + .name = "limit_rate", + .description = "Limit sending rate", + .type = PLUGIN_TYPE_HOOK, + .hook = { + .flags = HOOK_NODE | HOOK_PATH, + .priority = 99, + .init = limit_rate_init, + .parse = limit_rate_parse, + .write = limit_rate_write, + .size = sizeof(struct limit_rate) + } +}; + +REGISTER_PLUGIN(&p) + +/** @} */ diff --git a/tests/integration/hook-limit_rate.sh b/tests/integration/hook-limit_rate.sh new file mode 100755 index 000000000..11e42e3a7 --- /dev/null +++ b/tests/integration/hook-limit_rate.sh @@ -0,0 +1,41 @@ +#!/bin/bash +# +# Integration test for limit_rate hook. +# +# @author Steffen Vogel +# @copyright 2018 Institute for Automation of Complex Power Systems, EONERC +# @license GNU General Public License (version 3) +# +# VILLASnode +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . +################################################################################## + +INPUT_FILE=$(mktemp) +OUTPUT_FILE=$(mktemp) +EXPECT_FILE=$(mktemp) + +villas-signal sine -r 1000 -l 1000 -n > ${INPUT_FILE} +awk 'NR % 10 == 2' < ${INPUT_FILE} > ${EXPECT_FILE} + +villas-hook limit_rate -o rate=100 -o mode=origin < ${INPUT_FILE} > ${OUTPUT_FILE} + +# Compare only the data values +villas-test-cmp ${OUTPUT_FILE} ${EXPECT_FILE} + +RC=$? + +rm -f ${INPUT_FILE} ${OUTPUT_FILE} ${EXPECT_FILE} + +exit $RC