Getblocktemplate doesnt yield coinbasetxn? #11061

Hello accordenly with the "help" getblocktemplate shows:

Arguments:
1. template_request         (json object, optional) A json object in the following spec
     {
       "mode":"template"    (string, optional) This must be set to "template", "proposal" (see BIP 23), or omitted
       "capabilities":[     (array, optional) A list of strings
           "support"          (string) client side supported feature, 'longpoll', 'coinbasetxn', 'coinbasevalue', 'proposal', 'serverlist', 'workid'
           ,...
       ],
       "rules":[            (array, optional) A list of strings
           "support"          (string) client side supported softfork deployment
           ,...
       ]
     }

however passing any of these inputs longpoll, coinbasetxn, coinbasevalue, proposal, serverlist, workid seems to change the result in anyhow...

im trying to get the coinbasetxn but it doesnt seem to yield it doesnt matter what capabilities i fill in... any known bug here?

Bitcoin Core version v0.14.2 (64-bit)

Bitcoin Core does not support coinbasetxn.

So the help that it yields is inaccurate? (maybe outdated?) if so there are any other tools that does it? or i have to generate by hand?

The help doesn't say bitcoind does anything in particular with the client capabilities list.

At least Eloipool supports coinbasetxn, but you can also generate one using libblkmaker, the reference GBT client.

Look this is the entire output from the bitcoin-core

help getblocktemplate

getblocktemplate ( TemplateRequest )

If the request parameters include a 'mode' key, that is used to explicitly select between the default 'template' request or a 'proposal'.
It returns data needed to construct a block to work on.
For full specification, see BIPs 22, 23, 9, and 145:
    https://github.com/bitcoin/bips/blob/master/bip-0022.mediawiki
    https://github.com/bitcoin/bips/blob/master/bip-0023.mediawiki
    https://github.com/bitcoin/bips/blob/master/bip-0009.mediawiki#getblocktemplate_changes
    https://github.com/bitcoin/bips/blob/master/bip-0145.mediawiki

Arguments:
1. template_request         (json object, optional) A json object in the following spec
     {
       "mode":"template"    (string, optional) This must be set to "template", "proposal" (see BIP 23), or omitted
       "capabilities":[     (array, optional) A list of strings
           "support"          (string) client side supported feature, 'longpoll', 'coinbasetxn', 'coinbasevalue', 'proposal', 'serverlist', 'workid'
           ,...
       ],
       "rules":[            (array, optional) A list of strings
           "support"          (string) client side supported softfork deployment
           ,...
       ]
     }


Result:
{
  "version" : n,                    (numeric) The preferred block version
  "rules" : [ "rulename", ... ],    (array of strings) specific block rules that are to be enforced
  "vbavailable" : {                 (json object) set of pending, supported versionbit (BIP 9) softfork deployments
      "rulename" : bitnumber          (numeric) identifies the bit number as indicating acceptance and readiness for the named softfork rule
      ,...
  },
  "vbrequired" : n,                 (numeric) bit mask of versionbits the server requires set in submissions
  "previousblockhash" : "xxxx",     (string) The hash of current highest block
  "transactions" : [                (array) contents of non-coinbase transactions that should be included in the next block
      {
         "data" : "xxxx",             (string) transaction data encoded in hexadecimal (byte-for-byte)
         "txid" : "xxxx",             (string) transaction id encoded in little-endian hexadecimal
         "hash" : "xxxx",             (string) hash encoded in little-endian hexadecimal (including witness data)
         "depends" : [                (array) array of numbers 
             n                          (numeric) transactions before this one (by 1-based index in 'transactions' list) that must be present in the final block if this one is
             ,...
         ],
         "fee": n,                    (numeric) difference in value between transaction inputs and outputs (in Satoshis); for coinbase transactions, this is a negative Number of the total collected block fees (ie, not including the block subsidy); if key is not present, fee is unknown and clients MUST NOT assume there isn't one
         "sigops" : n,                (numeric) total SigOps cost, as counted for purposes of block limits; if key is not present, sigop cost is unknown and clients MUST NOT assume it is zero
         "weight" : n,                (numeric) total transaction weight, as counted for purposes of block limits
         "required" : true|false      (boolean) if provided and true, this transaction must be in the final block
      }
      ,...
  ],
  "coinbaseaux" : {                 (json object) data that should be included in the coinbase's scriptSig content
      "flags" : "xx"                  (string) key name is to be ignored, and value included in scriptSig
  },
  "coinbasevalue" : n,              (numeric) maximum allowable input to coinbase transaction, including the generation award and transaction fees (in Satoshis)
  "coinbasetxn" : { ... },          (json object) information for coinbase transaction
  "target" : "xxxx",                (string) The hash target
  "mintime" : xxx,                  (numeric) The minimum timestamp appropriate for next block time in seconds since epoch (Jan 1 1970 GMT)
  "mutable" : [                     (array of string) list of ways the block template may be changed 
     "value"                          (string) A way the block template may be changed, e.g. 'time', 'transactions', 'prevblock'
     ,...
  ],
  "noncerange" : "00000000ffffffff",(string) A range of valid nonces
  "sigoplimit" : n,                 (numeric) limit of sigops in blocks
  "sizelimit" : n,                  (numeric) limit of block size
  "weightlimit" : n,                (numeric) limit of block weight
  "curtime" : ttt,                  (numeric) current timestamp in seconds since epoch (Jan 1 1970 GMT)
  "bits" : "xxxxxxxx",              (string) compressed target of next block
  "height" : n                      (numeric) The height of the next block
}

Examples:
> bitcoin-cli getblocktemplate 
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "getblocktemplate", "params": [] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/

Close look to

"coinbasetxn" : { ... },          (json object) information for coinbase transaction

Maybe it's misleading ... i have tried using the bitcoin-cli and that console inside the bitcoin-core also have tried trough json rpc but none seems to work..

Bitcoin does not produce the coinbasetxn for you, you will have to build it manually.

As suggested by @luke-jr , you could check the following - bitcoin / libblkmaker. Its official and pretty simple to use.

Or, you could also go through bitcoin's testing framework and see how coinbase is created. Check this link for starters.