# RPC

The client exposes HTTP and WS endpoints for RPC connections. The default ports are 9933 for HTTP and 9944 for WS but can be specified running the client with the following parameters:`--ws-port 7949  --rpc-port 7939.`

To **run a full node without mining and expose certain RPC and HTTP port**, use the following command:

```typescript
betelgeuse --chain betelgeuse.json --port 41337  --ws-port 7949  --rpc-port 7939 --rpc-methods 'Unsafe' --unsafe-ws-external --unsafe-rpc-external --rpc-cors "all"
```

To **get a list of all RPC methods**, the node has an RPC endpoint called `rpc_methods`:

```typescript
$ curl -H "Content-Type: application/json" -d '{"id":1, "jsonrpc":"2.0", "method": "rpc_methods"}' http://localhost:9933/
```

*Response:*

`{"jsonrpc":"2.0","result":{"methods":["account_nextIndex","author_hasKey","author_hasSessionKeys","author_insertKey","author_pendingExtrinsics","author_removeExtrinsic","author_rotateKeys","author_submitAndWatchExtrinsic","author_submitExtrinsic","author_unwatchExtrinsic","chain_getBlock","chain_getBlockHash","chain_getFinalisedHead","chain_getFinalizedHead","chain_getHead","chain_getHeader","chain_getRuntimeVersion","chain_subscribeAllHeads","chain_subscribeFinalisedHeads","chain_subscribeFinalizedHeads","chain_subscribeNewHead","chain_subscribeNewHeads","chain_subscribeRuntimeVersion","chain_unsubscribeAllHeads","chain_unsubscribeFinalisedHeads","chain_unsubscribeFinalizedHeads","chain_unsubscribeNewHead","chain_unsubscribeNewHeads","chain_unsubscribeRuntimeVersion","offchain_localStorageGet","offchain_localStorageSet","payment_queryInfo","state_call","state_callAt","state_getChildKeys","state_getChildStorage","state_getChildStorageHash","state_getChildStorageSize","state_getKeys","state_getKeysPaged","state_getKeysPagedAt","state_getMetadata","state_getPairs","state_getRuntimeVersion","state_getStorage","state_getStorageAt","state_getStorageHash","state_getStorageHashAt","state_getStorageSize","state_getStorageSizeAt","state_queryStorage","state_subscribeRuntimeVersion","state_subscribeStorage","state_unsubscribeRuntimeVersion","state_unsubscribeStorage","subscribe_newHead","system_accountNextIndex","system_addReservedPeer","system_chain","system_health","system_name","system_networkState","system_nodeRoles","system_peers","system_properties","system_removeReservedPeer","system_version","unsubscribe_newHead"],"version":1},"id":1}`

**Add parameters in the call**. For example, get a block by its hash value:

```typescript
$ curl -H "Content-Type: application/json" -d '{"id":1, "jsonrpc":"2.0", "method": "chain_getBlock", "params":["0x3fa6a530850324391fde50bdf0094bdc17ee17ec84aca389b4047ef54fea0037"]}' http://localhost:9933
```

*Response:*

`{"jsonrpc":"2.0","result":{"block":{"extrinsics":["0x280402000b50055ee97001","0x1004140000"],"header":{"digest":{"logs":["0x06424142453402af000000937fbd0f00000000","0x054241424501011e38401b0aab22f4d72ebc95329c3798445786b92ca1ae69366aacb6e1584851f5fcdfcc0f518df121265c343059c62ab0a34e8e88fda8578810fbe508b6f583"]},"extrinsicsRoot":"0x0e354333c062892e774898e7ff5e23bf1cdd8314755fac15079e25c1a7765f06","number":"0x16c28c","parentHash":"0xe3bf2e8f0e901c292de24d07ebc412d67224ce52a3d1ffae76dc4bd78351e8ac","stateRoot":"0xd582f0dfeb6a7c73c47db735ae82d37fbeb5bada67ee8abcd43479df0f8fc8d8"}},"justification":null},"id":1}`

Betelgeuse node uses [SCALE encoding](https://substrate.dev/docs/en/knowledgebase/advanced/codec) as a format that is suitable for resource-constrained execution environments. You will need to decode the information and use the chain [metadata](https://substrate.dev/docs/en/knowledgebase/runtime/metadata) (`state_getMetadata`) to obtain human-readable information.

### **Tracking the Chain Head**

Use the RPC endpoint`chain_subscribeFinalizedHeads`to subscribe to a stream of hashes of finalized headers, or`chain_FinalizedHeads`to fetch the finalized header's latest hash. Use`chain_getBlock`to get the block associated with a given hash. `chain_getBlock`only accepts block hashes, so if you need to query intermediate blocks, use`chain_getBlockHash`to get the block hash from a block number.