json interface

The json interface is a json object describing the Application Binary Interface (ABI) for a smart contract. Using this json interface, web3.js is able to create JavaScript object representing the smart contract and its methods and events using the web3.eth.Contract object.
Specification
Functions:
1.
type: "function", "constructor" (can be omitted, defaulting to "function"; "fallback" also possible but not relevant in web3.js).
2.
name: the name of the function (only present for function types).
3.
constant: true if function is specified to not modify the blockchain state.
4.
payable: true if function accepts ether, defaults to false
5.
stateMutability: a string with one of the following values: 
1.
pure (specified to not read blockchain state)
2.
view (same as constant above)
3.
nonpayable and payable (same as payable above)
6.
inputs: an array of objects, each of which contains:
1.
name: the name of the parameter
2.
type: the canonical type of the parameter
7.
outputs: an array of objects same as inputs, can be omitted if no outputs exist.
Events:
1.
type: always "event"
2.
name: the name of the event.
3.
inputs: an array of objects, each of which contains:
1.
name: the name of the parameter.
2.
type: the canonical type of the parameter.
3.
indexed: true if the field is part of the log's topics, false if it one of the log's data segment.
4.
anonymous: true if the event was declared as anonymous.
Example:
1
contract Test {
2
        uint a;
3
        address d = 0x12345678901234567890123456789012;
4
​
5
        function Test(uint testInt)  { a = testInt;}
6
​
7
        event Event(uint indexed b, bytes32 c);
8
​
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        event Event2(uint indexed b, bytes32 c);
10
​
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        function foo(uint b, bytes32 c) returns(address) {
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            Event(b, c);
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            return d;
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        }
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    }
16
​
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    // would result in the JSON:
18
    [{
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        "type":"constructor",
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        "payable":false,
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        "stateMutability":"nonpayable"
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        "inputs":[{"name":"testInt","type":"uint256"}],
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      },{
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        "type":"function",
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        "name":"foo",
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        "constant":false,
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        "payable":false,
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        "stateMutability":"nonpayable",
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        "inputs":[{"name":"b","type":"uint256"}, {"name":"c","type":"bytes32"}],
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        "outputs":[{"name":"","type":"address"}]
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      },{
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        "type":"event",
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        "name":"Event",
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        "inputs":[{"indexed":true,"name":"b","type":"uint256"}, {"indexed":false,"name":"c","type":"bytes32"}],
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        "anonymous":false
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      },{
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        "type":"event",
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        "name":"Event2",
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        "inputs":[{"indexed":true,"name":"b","type":"uint256"},{"indexed":false,"name":"c","type":"bytes32"}],
40
        "anonymous":false
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    }]
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Specification