Stratum RPC Protocol
This document describes the current Stratum RPC protocol implemented in Grin.
Messages
In this section, we detail each message and the potential response.
getjobtemplate
A message initiated by the miner. Miner can request a job with this message.
Request
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "getjobtemplate" |
| params | null |
Example:
{
"id":"2",
"jsonrpc":"2.0",
"method":"getjobtemplate",
"params":null
}
The response can be of two types:
OK response
Example:
{
"id":"0",
"jsonrpc":"2.0",
"method":"getjobtemplate",
"result":{
"difficulty":1,
"height":13726,
"job_id":4,
"pre_pow":"00010000000000003c4d0171369781424b39c81eb39de10cdf4a7cc27bbc6769203c7c9bc02cc6a1dfc6000000005b50f8210000000000395f123c6856055aab2369fe325c3d709b129dee5c96f2db60cdbc0dc123a80cb0b89e883ae2614f8dbd169888a95c0513b1ac7e069de82e5d479cf838281f7838b4bf75ea7c9222a1ad7406a4cab29af4e018c402f70dc8e9ef3d085169391c78741c656ec0f11f62d41b463c82737970afaa431c5cabb9b759cdfa52d761ac451276084366d1ba9efff2db9ed07eec1bcd8da352b32227f452dfa987ad249f689d9780000000000000b9e00000000000009954"
}
}
Error response
If the node is syncing, it will send the following message:
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "getjobtemplate" |
| error |
Example:
{
"id":"10",
"jsonrpc":"2.0",
"method":"getjobtemplate",
"error":{
"code":-32000,
"message":"Node is syncing - Please wait"
}
}
job
A message initiated by the Stratum server. Stratum server will send job automatically to connected miners. The miner SHOULD interrupt current job if job_id = 0, and SHOULD replace the current job with this one after the current graph is complete.
Request
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "job" |
| params | Int difficulty, height, job_id and string pre_pow |
Example:
{
"id":"Stratum",
"jsonrpc":"2.0",
"method":"job",
"params":{
"difficulty":1,
"height":16375,
"job_id":5,
"pre_pow":"00010000000000003ff723bc8c987b0c594794a0487e52260c5343288749c7e288de95a80afa558c5fb8000000005b51f15f00000000003cadef6a45edf92d2520bf45cbd4f36b5ef283c53d8266bbe9aa1b8daaa1458ce5578fcb0978b3995dd00e3bfc5a9277190bb9407a30d66aec26ff55a2b50214b22cdc1f3894f27374f568b2fe94d857b6b3808124888dd5eff7e8de7e451ac805a4ebd6551fa7a529a1b9f35f761719ed41bfef6ab081defc45a64a374dfd8321feac083741f29207b044071d93904986fa322df610e210c543c2f95522c9bdaef5f598000000000000c184000000000000a0cf"
}
}
Response
No response is required for this message.
keepalive
A message initiated by the miner in order to keep the connection alive.
Request
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "keepalive" |
| params | null |
Example:
{
"id":"2",
"jsonrpc":"2.0",
"method":"keepalive",
"params":null
}
Response
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "keepalive" |
| result | "ok" |
| error | null |
Example:
{
"id":"2",
"jsonrpc":"2.0",
"method":"keepalive",
"result":"ok",
"error":null
}
login
A message initiated by the miner. Miner can log in on a Grin Stratum server with a login, password and agent (usually statically set by the miner program).
Request
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "login" |
| params | Strings: login, pass and agent |
Example:
{
"id":"0",
"jsonrpc":"2.0",
"method":"login",
"params":{
"login":"login",
"pass":"password",
"agent":"grin-miner"
}
}
The response can be of two types:
OK response
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "login" |
| result | "ok" |
| error | null |
Example:
{
"id":"1",
"jsonrpc":"2.0",
"method":"login",
"result":"ok",
"error":null
}
Error response
Not yet implemented. Should return error -32500 "Login first" when login is required.
status
A message initiated by the miner. This message allows a miner to get the status of its current worker and the network.
Request
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "status" |
| params | null |
Example:
{
"id":"2",
"jsonrpc":"2.0",
"method":"status",
"params":null
}
Response
The response is the following:
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "status" |
| result | String id. Integers height, difficulty, accepted, rejected and stale |
| error | null |
Example:
{
"id":"5",
"jsonrpc":"2.0",
"method":"status",
"result":{
"id":"5",
"height":13726,
"difficulty":1,
"accepted":0,
"rejected":0,
"stale":0
},
"error":null
}
submit
A message initiated by the miner. When a miner find a share, it will submit it to the node.
Request
The miner submit a solution to a job to the Stratum server.
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "submit" |
| params | Int edge_bits,nonce, height, job_id and array of integers pow |
Example:
{
"id":"0",
"jsonrpc":"2.0",
"method":"submit",
"params":{
"edge_bits":29,
"height":16419,
"job_id":0,
"nonce":8895699060858340771,
"pow":[
4210040,10141596,13269632,24291934,28079062,84254573,84493890,100560174,100657333,120128285,130518226,140371663,142109188,159800646,163323737,171019100,176840047,191220010,192245584,198941444,209276164,216952635,217795152,225662613,230166736,231315079,248639876,263910393,293995691,298361937,326412694,330363619,414572127,424798984,426489226,466671748,466924466,490048497,495035248,496623057,502828197, 532838434
]
}
}
The response can be of three types.
OK response
The share is accepted by the Stratum but is not a valid cuck(at)oo solution at the network target difficulty.
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "submit" |
| result | "ok" |
| error | null |
Example:
{
"id":"2",
"jsonrpc":"2.0",
"method":"submit",
"result":"ok",
"error":null
}
Blockfound response
The share is accepted by the Stratum and is a valid cuck(at)oo solution at the network target difficulty.
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "submit" |
| result | "block - " + hash of the block |
| error | null |
Example:
{
"id":"6",
"jsonrpc":"2.0",
"method":"submit",
"result":"blockfound - 23025af9032de812d15228121d5e4b0e977d30ad8036ab07131104787b9dcf10",
"error":null
}
Error response
The error response can be of two types: stale and rejected.
Stale share error response
The share is a valid solution to a previous job not the current one.
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "submit" |
| error |
Example:
{
"id":"5",
"jsonrpc":"2.0",
"method":"submit",
"error":{
"code":-32503,
"message":"Solution submitted too late"
}
}
Rejected share error responses
Two possibilities: the solution cannot be validated or the solution is of too low difficulty.
Failed to validate solution error
The submitted solution cannot be validated.
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "submit" |
| error |
Example:
{
"id":"5",
"jsonrpc":"2.0",
"method":"submit",
"error":{
"code":-32502,
"message":"Failed to validate solution"
}
}
Share rejected due to low difficulty error
The submitted solution is of too low difficulty.
| Field | Content |
|---|---|
| id | ID of the request |
| jsonrpc | "2.0" |
| method | "submit" |
| error |
Example:
{
"id":"5",
"jsonrpc":"2.0",
"method":"submit",
"error":{
"code":-32501,
"message":"Share rejected due to low difficulty"
}
}
Error Messages
Grin Stratum protocol implementation contains the following error message:
| Error code | Error Message |
|---|---|
| -32000 | Node is syncing - please wait |
| -32500 | Login first |
| -32501 | Share rejected due to low difficulty |
| -32502 | Failed to validate solution |
| -32503 | Solution Submitted too late |
| -32600 | Invalid Request |
| -32601 | Method not found |
Miner behavior
Miners SHOULD, MAY or MUST respect the following rules:
- Miners SHOULD randomize the job nonce before starting
- Miners MUST continue mining the same job until the server sends a new one, though a miner MAY request a new job at any time
- Miners MUST NOT send an rpc response to a job request from the server
- Miners MAY set the RPC "id" and expect responses to have that same id
- Miners MAY send a keepalive message
- Miners MAY send a login request (to identify which miner finds shares / solutions in the logs), the login request MUST have all 3 params.
- Miners MUST return the supplied job_id with submit messages.
Reference Implementation
The current reference implementation is available at mimblewimble/grin-miner.