/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package conf

import (
	"fmt"
	"os"
)

//
// Configuration keys for HTrace.
//

// The platform-specific path separator.  Usually slash.
var PATH_SEP string = fmt.Sprintf("%c", os.PathSeparator)

// The platform-specific path list separator.  Usually colon.
var PATH_LIST_SEP string = fmt.Sprintf("%c", os.PathListSeparator)

// The name of the XML configuration file to look for.
const CONFIG_FILE_NAME = "htraced-conf.xml"

// An environment variable containing a list of paths to search for the
// configuration file in.
const HTRACED_CONF_DIR = "HTRACED_CONF_DIR"

// The web address to start the REST server on.
const HTRACE_WEB_ADDRESS = "web.address"

// The default port for the Htrace web address.
const HTRACE_WEB_ADDRESS_DEFAULT_PORT = 9096

// The web address to start the REST server on.
const HTRACE_HRPC_ADDRESS = "hrpc.address"

// The default port for the Htrace HRPC address.
const HTRACE_HRPC_ADDRESS_DEFAULT_PORT = 9075

// The directories to put the data store into.  Separated by PATH_LIST_SEP.
const HTRACE_DATA_STORE_DIRECTORIES = "data.store.directories"

// Boolean key which indicates whether we should clear data on startup.
const HTRACE_DATA_STORE_CLEAR = "data.store.clear"

// How many writes to buffer before applying backpressure to span senders.
const HTRACE_DATA_STORE_SPAN_BUFFER_SIZE = "data.store.span.buffer.size"

// Path to put the logs from htrace, or the empty string to use stdout.
const HTRACE_LOG_PATH = "log.path"

// The log level to use for the logs in htrace.
const HTRACE_LOG_LEVEL = "log.level"

// The period between datastore heartbeats.  This is the approximate interval at which we will
// prune expired spans.
const HTRACE_DATASTORE_HEARTBEAT_PERIOD_MS = "datastore.heartbeat.period.ms"

// The maximum number of addresses for which we will maintain metrics.
const HTRACE_METRICS_MAX_ADDR_ENTRIES = "metrics.max.addr.entries"

// The number of milliseconds we should keep spans before discarding them.
const HTRACE_SPAN_EXPIRY_MS = "span.expiry.ms"

// The period between updates to the span reaper
const HTRACE_REAPER_HEARTBEAT_PERIOD_MS = "reaper.heartbeat.period.ms"

// A host:port pair to send information to on startup.  This is used in unit
// tests to determine the (random) port of the htraced process that has been
// started.
const HTRACE_STARTUP_NOTIFICATION_ADDRESS = "startup.notification.address"

// The maximum number of HRPC handler goroutines we will create at once.  If
// this is too small, we won't get enough concurrency; if it's too big, we will
// buffer too much data in memory while waiting for the datastore to process
// requests.
const HTRACE_NUM_HRPC_HANDLERS = "num.hrpc.handlers"

// The I/O timeout HRPC will use, in milliseconds.  If it takes longer than
// this to read or write a message, we will abort the connection.
const HTRACE_HRPC_IO_TIMEOUT_MS = "hrpc.io.timeout.ms"

// The leveldb write buffer size, or 0 to use the library default, which is 4
// MB in leveldb 1.16.  See leveldb's options.h for more details.
const HTRACE_LEVELDB_WRITE_BUFFER_SIZE = "leveldb.write.buffer.size"

// The LRU cache size for leveldb, in bytes.
const HTRACE_LEVELDB_CACHE_SIZE = "leveldb.cache.size"

// Default values for HTrace configuration keys.
var DEFAULTS = map[string]string{
	HTRACE_WEB_ADDRESS:  fmt.Sprintf("0.0.0.0:%d", HTRACE_WEB_ADDRESS_DEFAULT_PORT),
	HTRACE_HRPC_ADDRESS: fmt.Sprintf("0.0.0.0:%d", HTRACE_HRPC_ADDRESS_DEFAULT_PORT),
	HTRACE_DATA_STORE_DIRECTORIES: PATH_SEP + "tmp" + PATH_SEP + "htrace1" +
		PATH_LIST_SEP + PATH_SEP + "tmp" + PATH_SEP + "htrace2",
	HTRACE_DATA_STORE_CLEAR:              "false",
	HTRACE_DATA_STORE_SPAN_BUFFER_SIZE:   "100",
	HTRACE_LOG_PATH:                      "",
	HTRACE_LOG_LEVEL:                     "INFO",
	HTRACE_DATASTORE_HEARTBEAT_PERIOD_MS: fmt.Sprintf("%d", 45*1000),
	HTRACE_METRICS_MAX_ADDR_ENTRIES:      "100000",
	HTRACE_SPAN_EXPIRY_MS:                "0",
	HTRACE_REAPER_HEARTBEAT_PERIOD_MS:    fmt.Sprintf("%d", 90*1000),
	HTRACE_NUM_HRPC_HANDLERS:             "20",
	HTRACE_HRPC_IO_TIMEOUT_MS:            "60000",
	HTRACE_LEVELDB_WRITE_BUFFER_SIZE:     "0",
	HTRACE_LEVELDB_CACHE_SIZE:            fmt.Sprintf("%d", 100*1024*1024),
}

// Values to be used when creating test configurations
func TEST_VALUES() map[string]string {
	return map[string]string{
		HTRACE_HRPC_ADDRESS:   ":0",    // use a random port for the HRPC server
		HTRACE_LOG_LEVEL:      "TRACE", // show all log messages in tests
		HTRACE_WEB_ADDRESS:    ":0",    // use a random port for the REST server
		HTRACE_SPAN_EXPIRY_MS: "0",     // never time out spans (unless testing the reaper)
	}
}