# Task State Transitions

## State Transition Graph

The task could be aborted at any state, as long as the timeout period has reached. The abort action could be issued from both the application and the selected node. 

The task state transition graph is given below. **To simplify the graph, all the abort transition is omitted**:

{% @mermaid/diagram content="stateDiagram-v2
state "Queued" as q
state "Started" as s
state "Parameters Uploaded" as pu
state "Error Reported" as er
state "Score Ready" as sr
state "Validated" as v
state "Group Validated" as gv
state "End Group Refund" as egr
state "End Success" as es
state "End Group Success" as egs
state "End Invalidated" as ei
state "End Aborted" as ea

\[*] --> q: App - create task
\[*] --> s: App - create task
q --> s: Blockchain - start task
s --> pu: Relay - report parameters uploaded
pu --> sr: Node - submit task score
pu --> er: Node - report task error
sr --> ei: App - validate task group
sr --> v: App - validate single task
sr --> gv: App - validate task group
gv --> egs: Relay - report result uploaded
sr --> egr: App - validate task group
er --> ea: App - validate single task<br/>App - validate task group
er --> ei: App - validate task group
v --> es: Relay - report result uploaded
ea --> ea: App - validate task group
es --> \[*]
egr --> \[*]
egs --> \[*]
ei --> \[*]
ea --> \[\*]
" fullWidth="true" %}

## Group Validation Results

When a task is validated in a validation group, its result state is determined according to the table below:

<table data-full-width="true"><thead><tr><th width="191">Task 1 Before</th><th width="182">Task 2 Before</th><th width="165">Task 3 Before</th><th width="165">Task 1 After</th><th width="172">Task 2 After</th><th>Task 3 After</th></tr></thead><tbody><tr><td>ScoreReady (A)</td><td>ScoreReady (A)</td><td>ScoreReady (A)</td><td>GroupValidated</td><td>EndGroupRefund</td><td>EndGroupRefund</td></tr><tr><td>ScoreReady (A)</td><td>ScoreReady (A)</td><td>ScoreReady (B)</td><td>GroupValidated</td><td>EndGroupRefund</td><td>EndInvalidated</td></tr><tr><td>ScoreReady (A)</td><td>ScoreReady (B)</td><td>ScoreReady (C)</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ScoreReady (A)</td><td>ScoreReady (A)</td><td>ErrorReported</td><td>GroupValidated</td><td>EndGroupRefund</td><td>EndInvalidated</td></tr><tr><td>ScoreReady (A)</td><td>ScoreReady (B)</td><td>ErrorReported</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ScoreReady (A)</td><td>ScoreReady (A)</td><td>EndAborted</td><td>GroupValidated</td><td>EndGroupRefund</td><td>EndAborted</td></tr><tr><td>ScoreReady (A)</td><td>ScoreReady (B)</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ScoreReady</td><td>ErrorReported</td><td>ErrorReported</td><td>EndInvalidated</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ScoreReady</td><td>ErrorReported</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ScoreReady</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ErrorReported</td><td>ErrorReported</td><td>ErrorReported</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ErrorReported</td><td>ErrorReported</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>ErrorReported</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr><tr><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td><td>EndAborted</td></tr></tbody></table>

## Actions for Each State

<table><thead><tr><th width="248">State</th><th>Action</th></tr></thead><tbody><tr><td>Group Validated</td><td>Record the address of all the 3 nodes in the validation group.</td></tr><tr><td>End Success</td><td>Settle the payment. Release the node.</td></tr><tr><td>End Group Refund</td><td>Refund the payment. Release the node.</td></tr><tr><td>End Group Success</td><td>Distribute payment to 3 nodes. Release the node.</td></tr><tr><td>End Invalidated</td><td>Refund the payment. Slash the node.</td></tr><tr><td>End Aborted</td><td>Refund the payment. Release the node.</td></tr></tbody></table>