# vim: set et nosta sw=4 ts=4 ft=nim : 

#

# Copyright (c) 2018, Mahlon E. Smith <mahlon@martini.nu>

# All rights reserved.

# Redistribution and use in source and binary forms, with or without

# modification, are permitted provided that the following conditions are met:

#

#     * Redistributions of source code must retain the above copyright

#       notice, this list of conditions and the following disclaimer.

#

#     * Redistributions in binary form must reproduce the above copyright

#       notice, this list of conditions and the following disclaimer in the

#       documentation and/or other materials provided with the distribution.

#

#     * Neither the name of Mahlon E. Smith nor the names of his

#       contributors may be used to endorse or promote products derived

#       from this software without specific prior written permission.

#

# THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY

# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

# DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY

# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

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# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import

    db_postgres,

    json,

    nativesockets,

    net,

    parseopt2,

    strutils,

    tables,

    threadpool

const

    VERSION = "v0.1.0"

    USAGE = """

The default connection string is:

  "host=localhost port=5432 dbname=netdata user=netdata application_name=netdata-tsrelay"

    """

    INSERT_SQL = """

    INSERT INTO netdata

        ( time, host, metrics )

    VALUES

        ( 'epoch'::timestamptz + ? * '1 second'::interval, ?, ? )

    """

#

var conf = Config(

    dbopts: "host=localhost port=5432 dbname=netdata user=netdata application_name=netdata-tsrelay",

)

proc fetch_data( client: Socket ): string =

    ## Netdata JSON backend doesn't send a length, so we read line by

    ## line and wait for stream timeout to determine a "sample".

    try:

        result = client.recv_line( timeout=500 ) & "\n"

        while result != "":

            result = result & client.recv_line( timeout=500 ) & "\n"

    except TimeoutError:

        discard

    ## Given a raw +data+ string, parse JSON and return a table of

    ## JSON samples ready for writing, keyed by timestamp. Netdata can

    ## buffer multiple samples in one batch.

    if data == "": return

    # Hash of sample timeperiods to pivoted json data

    result = init_table[ BiggestInt, JsonNode ]()

    for sample in split_lines( data ):

        if sample.len == 0: continue

        var parsed: JsonNode

        try:

            parsed = sample.parse_json

        except JsonParsingError:

        # Create or use existing Json object for modded data.

        #

        var pivot: JsonNode

        let key = parsed["timestamp"].get_num

        if result.has_key( key ):

            pivot = result[ key ]

        else:

            pivot = newJObject()

            result[ key ] = pivot

        var name = parsed[ "chart_id" ].get_str & "." & parsed[ "id" ].get_str

        pivot[ "hostname" ] = parsed[ "hostname" ]

        pivot[ name ] = parsed[ "value" ]

    return result

    ## Do the work for a connected client within a thread.

    var raw_data = client.fetch_data

    try:

        client.close

    except OSError:

        return

proc serverloop: void =

    ## Open a database connection, bind to the listening socket,

    ## and start serving incoming netdata streams.

    let db = open( "", "", "", conf.dbopts )

    server.set_sock_opt( OptReuseAddr, true )

    server.listen()

    while true:

proc parse_cmdline: void =

    ## Populate the config object with the user's preferences.

    for kind, key, val in getopt():

        case kind

        of cmdArgument:

            discard

        of cmdLongOption, cmdShortOption:

            case key

                of "help", "h":

                    echo USAGE

                    quit( 0 )

                of "version", "v":

                    quit( 0 )

                of "dbopts": conf.dbopts = val

                of "listen-port", "p": conf.listen_port = val.parse_int

                else: discard

        of cmdEnd: assert( false ) # shouldn't reach here ever

when isMainModule:

    parse_cmdline()

    serverloop()