> ## Documentation Index
> Fetch the complete documentation index at: https://developers.stellar.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Retrieve a contract code ledger entry using the JavaScript SDK

> Retrieve a contract code ledger entry using the JavaScript SDK

When you deploy a contract, first the code is "installed" (i.e., it is uploaded onto the blockchain). This creates a `LedgerEntry` containing the Wasm byte-code, which is uniquely identified by its hash (that is, the hash of the uploaded code itself). Then, when the contract is "deployed," we create a `LedgerEntry` with a reference to that code's hash. So fetching the contract code is a two-step process:

1. First, we look up the contract itself, to see which code hash it is referencing.
2. Then, we can look up the raw Wasm byte-code using that hash.

```javascript theme={"theme":{"light":"github-light","dark":"github-dark"}}
import { Contract } from "@stellar/stellar-sdk";

function getLedgerKeyContractCode(contractId) {
  const instance = new Contract(contractId).getFootprint();
  return instance.toXDR("base64");
}

console.log(
  getLedgerKeyContractCode(
    "CCPYZFKEAXHHS5VVW5J45TOU7S2EODJ7TZNJIA5LKDVL3PESCES6FNCI",
  ),
);
// OUTPUT: AAAABgAAAAGfjJVEBc55drW3U87N1Py0Rw0/nlqUA6tQ6r28khEl4gAAABQAAAAB
```

We then take our output from this function, and use it as the element in the `keys` array parameter in our call to the `getLedgerEntries` method.

```json theme={"theme":{"light":"github-light","dark":"github-dark"}}
{
  "jsonrpc": "2.0",
  "id": 8675309,
  "method": "getLedgerEntries",
  "params": {
    "keys": ["AAAABgAAAAGfjJVEBc55drW3U87N1Py0Rw0/nlqUA6tQ6r28khEl4gAAABQAAAAB"]
  }
}
```

And the response we get contains the `LedgerEntryData` that can be used to find the `hash` we must use to request the Wasm byte-code. This hash is the `LedgerKey` that's been associated with the deployed contract code.

```json theme={"theme":{"light":"github-light","dark":"github-dark"}}
{
  "jsonrpc": "2.0",
  "id": 8675309,
  "result": {
    "entries": [
      {
        "key": "AAAABgAAAAGfjJVEBc55drW3U87N1Py0Rw0/nlqUA6tQ6r28khEl4gAAABQAAAAB",
        "xdr": "AAAABgAAAAAAAAABn4yVRAXOeXa1t1POzdT8tEcNP55alAOrUOq9vJIRJeIAAAAUAAAAAQAAABMAAAAA5DNtbckOGVRsNVb8L7X/lIhAOy2o5G6GkLKXvc7W8foAAAAA",
        "lastModifiedLedgerSeq": 261603
      }
    ],
    "latestLedger": 262322
  }
}
```

Now take the `xdr` field from the previous response's `result` object, and create a `LedgerKey` from the hash contained inside.

```javascript theme={"theme":{"light":"github-light","dark":"github-dark"}}
import { xdr } from "@stellar/stellar-sdk";

function getLedgerKeyWasmId(contractCodeLedgerEntryData) {
  const entry = xdr.LedgerEntryData.fromXDR(
    contractCodeLedgerEntryData,
    "base64",
  );

  const wasmHash = entry
    .contractData()
    .val()
    .instance()
    .executable()
    .wasmHash();

  let ledgerKey = xdr.LedgerKey.contractCode(
    new xdr.LedgerKeyContractCode({
      hash: wasmHash,
    }),
  );

  return ledgerKey.toXDR("base64");
}

console.log(
  getLedgerKeyWasmId(
    "AAAABgAAAAAAAAABn4yVRAXOeXa1t1POzdT8tEcNP55alAOrUOq9vJIRJeIAAAAUAAAAAQAAABMAAAAA5DNtbckOGVRsNVb8L7X/lIhAOy2o5G6GkLKXvc7W8foAAAAA",
  ),
);
// OUTPUT: AAAAB+QzbW3JDhlUbDVW/C+1/5SIQDstqORuhpCyl73O1vH6
```

Now, finally we have a `LedgerKey` that correspond to the Wasm byte-code that has been deployed under the `ContractId` we started out with so very long ago. This `LedgerKey` can be used in a final request to the Stellar-RPC endpoint.

```json theme={"theme":{"light":"github-light","dark":"github-dark"}}
{
  "jsonrpc": "2.0",
  "id": 8675309,
  "method": "getLedgerEntries",
  "params": {
    "keys": ["AAAAB+QzbW3JDhlUbDVW/C+1/5SIQDstqORuhpCyl73O1vH6"]
  }
}
```

And the response we get contains (even more) `LedgerEntryData` that we can decode and parse to get the actual, deployed, real-life contract byte-code. We'll leave that exercise up to you. You can check out what is contained using the ["View XDR" page of the Stellar Lab](https://lab.stellar.org/xdr/view?\$=network\$id=testnet\&label=Testnet\&horizonUrl=https:////horizon-testnet.stellar.org\&rpcUrl=https:////soroban-testnet.stellar.org\&passphrase=Test%20SDF%20Network%20/;%20September%202015;;).

```json theme={"theme":{"light":"github-light","dark":"github-dark"}}
{
  "jsonrpc": "2.0",
  "id": 8675309,
  "result": {
    "entries": [
      {
        "key": "AAAAB+QzbW3JDhlUbDVW/C+1/5SIQDstqORuhpCyl73O1vH6",
        "xdr": "AAAABwAAAADkM21tyQ4ZVGw1Vvwvtf+UiEA7LajkboaQspe9ztbx+gAAAkgAYXNtAQAAAAEVBGACfn4BfmADfn5+AX5gAAF+YAAAAhkEAWwBMAAAAWwBMQAAAWwBXwABAWwBOAAAAwUEAgMDAwUDAQAQBhkDfwFBgIDAAAt/AEGAgMAAC38AQYCAwAALBzUFBm1lbW9yeQIACWluY3JlbWVudAAEAV8ABwpfX2RhdGFfZW5kAwELX19oZWFwX2Jhc2UDAgqnAQSSAQIBfwF+QQAhAAJAAkACQEKOutCvhtQ5QgEQgICAgABCAVINAEKOutCvhtQ5QgEQgYCAgAAiAUL/AYNCBFINASABQiCIpyEACyAAQQFqIgBFDQFCjrrQr4bUOSAArUIghkIEhCIBQgEQgoCAgAAaQoSAgICgBkKEgICAwAwQg4CAgAAaIAEPCwAACxCFgICAAAALCQAQhoCAgAAACwQAAAALAgALAHMOY29udHJhY3RzcGVjdjAAAAAAAAAAQEluY3JlbWVudCBpbmNyZW1lbnRzIGFuIGludGVybmFsIGNvdW50ZXIsIGFuZCByZXR1cm5zIHRoZSB2YWx1ZS4AAAAJaW5jcmVtZW50AAAAAAAAAAAAAAEAAAAEAB4RY29udHJhY3RlbnZtZXRhdjAAAAAAAAAAFAAAAAAAbw5jb250cmFjdG1ldGF2MAAAAAAAAAAFcnN2ZXIAAAAAAAAGMS43Ni4wAAAAAAAAAAAACHJzc2RrdmVyAAAALzIwLjMuMSNiYTA0NWE1N2FmOTcxZmM4M2U0NzU3NDZiNTlhNTAzYjdlZjQxNjQ5AA==",
        "lastModifiedLedgerSeq": 368441,
        "liveUntilLedgerSeq": 2442040
      }
    ],
    "latestLedger": 370940
  }
}
```