Remote Procedure Calls
======================

We provide several different API's. Each API has its own ID. When running
`witness_node`, initially two API's are available:

* API 0: provides read-only access to the database
* API 1 is used to login and gain access to additional, restricted API's.

Unrestricted Calls
------------------

Since API 0 is state-less it is accessible via regular JSON-RPC calls like:::

    $ curl --data '{"jsonrpc": "2.0", "method": "get_accounts", "params": [["1.2.0"]], "id": 1}' http://127.0.0.1:8090/rpc

We can do the same thing using an HTTP client such as curl for API's which do
not require login or other session state:::

    $ curl --data '{"jsonrpc": "2.0", "method": "call", "params": [0, "get_accounts", [["1.2.0"]]], "id": 1}' http://127.0.0.1:8090/rpc
    {"id":1,"result":[{"id":"1.2.0","annotations":[],"membership_expiration_date":"1969-12-31T23:59:59","registrar":"1.2.0","referrer":"1.2.0","lifetime_referrer":"1.2.0","network_fee_percentage":2000,"lifetime_referrer_fee_percentage":8000,"referrer_rewards_percentage":0,"name":"committee-account","owner":{"weight_threshold":1,"account_auths":[],"key_auths":[],"address_auths":[]},"active":{"weight_threshold":6,"account_auths":[["1.2.5",1],["1.2.6",1],["1.2.7",1],["1.2.8",1],["1.2.9",1],["1.2.10",1],["1.2.11",1],["1.2.12",1],["1.2.13",1],["1.2.14",1]],"key_auths":[],"address_auths":[]},"options":{"memo_key":"GPH1111111111111111111111111111111114T1Anm","voting_account":"1.2.0","num_witness":0,"num_committee":0,"votes":[],"extensions":[]},"statistics":"2.7.0","whitelisting_accounts":[],"blacklisting_accounts":[]}]}

Restricted Calls
----------------

However, the restricted APIs require login and are **only** accessible over the
websocket RPC. Here is an example using wscat package from npm for websockets:::

    $ npm install -g wscat
    $ wscat -c ws://127.0.0.1:8090
    > {"id":1, "method":"call", "params":[0,"get_accounts",[["1.2.0"]]]}
    < {"id":1,"result":[{"id":"1.2.0","annotations":[],"membership_expiration_date":"1969-12-31T23:59:59","registrar":"1.2.0","referrer":"1.2.0","lifetime_referrer":"1.2.0","network_fee_percentage":2000,"lifetime_referrer_fee_percentage":8000,"referrer_rewards_percentage":0,"name":"committee-account","owner":{"weight_threshold":1,"account_auths":[],"key_auths":[],"address_auths":[]},"active":{"weight_threshold":6,"account_auths":[["1.2.5",1],["1.2.6",1],["1.2.7",1],["1.2.8",1],["1.2.9",1],["1.2.10",1],["1.2.11",1],["1.2.12",1],["1.2.13",1],["1.2.14",1]],"key_auths":[],"address_auths":[]},"options":{"memo_key":"GPH1111111111111111111111111111111114T1Anm","voting_account":"1.2.0","num_witness":0,"num_committee":0,"votes":[],"extensions":[]},"statistics":"2.7.0","whitelisting_accounts":[],"blacklisting_accounts":[]}]}

APIs
_______

The graphene witness node distinguishes sever different APIs for security
reasons:

* `database_api`
* `history_api`
* `network_broadcast_api`
* `network_node_api`
* `login_api`

The most important api for polling blockchain data is the `database_api`. A
list of all available calls can be found in
`graphene/libraries/app/include/graphene/app/database_api.hpp`.