Voting Oracle (Stateful)
Learn how stateful oracles maintain state across invocations
Step 1 of 5
Create Voting Oracle
Submit CreateScriptOracle message to create a stateful voting oracle
🔮 STATEFUL ORACLE CREATION: This oracle maintains state across invocations. Unlike the calculator oracle, this one has initialState that will be updated with each method call. The oracle supports create, vote, and close methods.
📨 Message Type: CreateScriptOracle
{
"cid": "voting-oracle-uuid",
"scriptProgram": {
"if": [
{
"==": [
{
"var": "method"
},
"create"
]
},
{
"if": [
{
"and": [
{
"exists": [
{
"var": "title"
},
{
"var": "options"
},
{
"var": "endTime"
}
]
},
{
">": [
{
"var": "endTime"
},
{
"var": "currentTime"
}
]
}
]
},
{
"title": {
"var": "title"
},
"options": {
"var": "options"
},
"voteCount": 0,
"endTime": {
"var": "endTime"
},
"active": true
},
"Failed create checks"
]
},
{
"==": [
{
"var": "method"
},
"vote"
]
},
{
"if": [
{
"and": [
{
"==": [
{
"var": "state.active"
},
true
]
},
{
"<": [
{
"var": "currentTime"
},
{
"var": "state.endTime"
}
]
},
{
"in": [
{
"var": "option"
},
{
"var": "state.options"
}
]
},
{
"in": [
{
"var": "voter"
},
{
"var": "participants"
}
]
}
]
},
{
"title": {
"var": "state.title"
},
"options": {
"var": "state.options"
},
"voteCount": {
"+": [
{
"var": "state.voteCount"
},
1
]
},
"lastVoter": {
"var": "voter"
},
"lastOption": {
"var": "option"
},
"endTime": {
"var": "state.endTime"
},
"active": {
"var": "state.active"
}
},
"Failed vote checks"
]
},
{
"==": [
{
"var": "method"
},
"close"
]
},
{
"if": [
{
"and": [
{
"==": [
{
"var": "state.active"
},
true
]
},
{
">=": [
{
"var": "currentTime"
},
{
"var": "state.endTime"
}
]
}
]
},
{
"title": {
"var": "state.title"
},
"options": {
"var": "state.options"
},
"voteCount": {
"var": "state.voteCount"
},
"endTime": {
"var": "state.endTime"
},
"active": false
},
"Failed close checks"
]
},
"Unknown method"
]
},
"initialState": null,
"accessControl": {
"Public": {}
}
}State Before
null
State After
null
Oracle Script Program
The voting oracle uses nested if statements to handle create, vote, and close methods. Notice how it references {var: "state.field"} to access the oracle's persistent state:
{
"if": [
{
"==": [
{
"var": "method"
},
"create"
]
},
{
"if": [
{
"and": [
{
"exists": [
{
"var": "title"
},
{
"var": "options"
},
{
"var": "endTime"
}
]
},
{
">": [
{
"var": "endTime"
},
{
"var": "currentTime"
}
]
}
]
},
{
"title": {
"var": "title"
},
"options": {
"var": "options"
},
"voteCount": 0,
"endTime": {
"var": "endTime"
},
"active": true
},
"Failed create checks"
]
},
{
"==": [
{
"var": "method"
},
"vote"
]
},
{
"if": [
{
"and": [
{
"==": [
{
"var": "state.active"
},
true
]
},
{
"<": [
{
"var": "currentTime"
},
{
"var": "state.endTime"
}
]
},
{
"in": [
{
"var": "option"
},
{
"var": "state.options"
}
]
},
{
"in": [
{
"var": "voter"
},
{
"var": "participants"
}
]
}
]
},
{
"title": {
"var": "state.title"
},
"options": {
"var": "state.options"
},
"voteCount": {
"+": [
{
"var": "state.voteCount"
},
1
]
},
"lastVoter": {
"var": "voter"
},
"lastOption": {
"var": "option"
},
"endTime": {
"var": "state.endTime"
},
"active": {
"var": "state.active"
}
},
"Failed vote checks"
]
},
{
"==": [
{
"var": "method"
},
"close"
]
},
{
"if": [
{
"and": [
{
"==": [
{
"var": "state.active"
},
true
]
},
{
">=": [
{
"var": "currentTime"
},
{
"var": "state.endTime"
}
]
}
]
},
{
"title": {
"var": "state.title"
},
"options": {
"var": "state.options"
},
"voteCount": {
"var": "state.voteCount"
},
"endTime": {
"var": "state.endTime"
},
"active": false
},
"Failed close checks"
]
},
"Unknown method"
]
}Key Concepts Demonstrated
Stateful Oracles
Oracles can maintain state across invocations, enabling complex workflows like voting, escrow, and marketplace contracts
State Transitions
Each invocation reads the current state, validates guards, and returns new state that persists for the next call
Business Rule Enforcement
Guards validate conditions like active status, deadlines, and participant authorization before allowing state changes
Accumulating Data
State like voteCount increments across invocations, demonstrating how oracles can aggregate information over time