feat: add script to get in chain tx cbor from tx id

Author: iccicci

README.md

@@ -137,6 +137,18 @@ for you.
 nix run .#config-update
 ```
 
+## Get CBOR representation of an on chain transaction
+
+Once we have a [running network](packages/cardano-services/README.md#production) synced at least up to the block
+containing the transaction we are interested in, issue following command to get the CBOR representation of the
+transaction.
+
+```
+yarn tx-cbor <txId>
+```
+
+This works regardless of the local ports configuration through environment variables.
+
 ## Attic
 
 Previously supported features, no longer supported, but packed with a reference branch.

package.json

@@ -37,7 +37,8 @@
     "test": "yarn workspaces foreach -v run test",
     "test:build:verify": "yarn workspaces foreach -v run test:build:verify",
     "test:e2e": "yarn workspaces foreach -v run test:e2e",
-    "test:debug": "DEBUG=true yarn workspaces foreach -v run test"
+    "test:debug": "DEBUG=true yarn workspaces foreach -v run test",
+    "tx-cbor": "tsx packages/cardano-services/scripts/tx-cbor.js"
   },
   "repository": {
     "type": "git",

packages/cardano-services/scripts/tx-cbor.ts

@@ -0,0 +1,105 @@
+import { Pool } from 'pg';
+import { readFileSync } from 'fs';
+import { spawnSync } from 'child_process';
+import WebSocket from 'ws';
+
+interface Tx {
+  cbor: string;
+  id: string;
+}
+
+const txId = process.argv[2];
+
+const normalizeError = (status: number | null, stderr: string) =>
+  [status || 1, stderr || 'Unknown error\n', ''] as const;
+
+const inside = async () => {
+  const db = new Pool({
+    database: readFileSync(process.env.POSTGRES_DB_FILE_DB_SYNC!).toString(),
+    host: 'postgres',
+    password: readFileSync(process.env.POSTGRES_PASSWORD_FILE_DB_SYNC!).toString(),
+    user: readFileSync(process.env.POSTGRES_USER_FILE_DB_SYNC!).toString()
+  });
+
+  const query = `\
+SELECT ENCODE(b2.hash, 'hex') AS id, b2.slot_no::INTEGER AS slot FROM tx
+JOIN block b1 ON block_id = b1.id
+JOIN block b2 ON b1.previous_id = b2.id
+WHERE tx.hash = $1`;
+
+  const { rows } = await db.query(query, [Buffer.from(txId, 'hex')]);
+  const [prevBlock] = rows;
+
+  await db.end();
+
+  if (!prevBlock) return [1, `Unknown transaction id ${txId}\n`, ''] as const;
+
+  const cbor = await new Promise<string>((resolve) => {
+    const client = new WebSocket(process.env.OGMIOS_URL!);
+    let request = 0;
+
+    const rpc = (method: string, params: unknown) =>
+      client.send(JSON.stringify({ id: ++request, jsonrpc: '2.0', method, params }));
+
+    client.on('open', () => rpc('findIntersection', { points: [prevBlock] }));
+
+    client.on('message', (msg) => {
+      const { result } = JSON.parse(msg.toString()) as { result: { block: { transactions: Tx[] } } };
+      let tx: Tx | undefined;
+
+      if (
+        result &&
+        result.block &&
+        result.block.transactions &&
+        (tx = result.block.transactions.find((t) => t.id === txId))
+      ) {
+        client.on('close', () => resolve(tx!.cbor));
+        client.close();
+      } else rpc('nextBlock', {});
+    });
+  });
+
+  return [0, '', `${cbor}\n`] as const;
+};
+
+const outside = async () => {
+  if (!txId) return [1, 'Missing input transaction id\n', ''] as const;
+
+  let { status, stderr, stdout } = spawnSync('docker', ['ps'], { encoding: 'utf-8' });
+
+  if (status || stderr) return normalizeError(status, stderr);
+
+  const container = [
+    'cardano-services-mainnet-provider-server-1',
+    'cardano-services-preprod-provider-server-1',
+    'cardano-services-preview-provider-server-1',
+    'cardano-services-sanchonet-provider-server-1',
+    'local-network-e2e-provider-server-1'
+  ].find((name) => stdout.includes(name));
+
+  if (!container) return [1, "Can't find any valid container\n", ''] as const;
+
+  ({ status, stderr, stdout } = spawnSync(
+    'docker',
+    ['container', 'exec', '-i', container, 'bash', '-c', `cd /app ; INSIDE_THE_CONTAINER=true yarn tx-cbor ${txId}`],
+    { encoding: 'utf-8' }
+  ));
+
+  if (status || stderr) return normalizeError(status, stderr);
+
+  return [0, '', stdout] as const;
+};
+
+(process.env.INSIDE_THE_CONTAINER ? inside() : outside())
+  .then(([status, stderr, stdout]) => {
+    if (status) {
+      process.stderr.write(stderr);
+      // eslint-disable-next-line unicorn/no-process-exit
+      process.exit(status);
+    }
+
+    process.stdout.write(stdout);
+  })
+  .catch((error) => {
+    throw error;
+  });