From 7936bc049e3812532f8fe4cf480c995e582ae20c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1s=20Gr=C3=BCner?=
 <47506558+MegaRedHand@users.noreply.github.com>
Date: Tue, 19 Dec 2023 15:14:53 -0300
Subject: [PATCH] docs: add `GetMetadata` example (#538)

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+# Metadata request example
+
+After sending a *GetMetadata* request to a peer, I get as a response:
+
+`0011ff060000734e6150705901150000cd11e7d53a03000000000000ffffffffffffffff0f`
+
+## *GetMetadata* request header
+
+Decoding it with the protocol described in the consensus specs (**Req/Resp interaction**), we get:
+
+```elixir
+# Status (success)
+"00"
+# Optional header (uncompressed length: 17)
+"11"
+# Encoded data
+"ff060000734e6150705901150000cd11e7d53a03000000000000ffffffffffffffff0f"
+```
+
+## *Snappy* framing format
+
+We can interpret the encoded data with the Snappy framing format described in [google/snappy](https://github.com/google/snappy/blob/main/framing_format.txt).
+Then we get:
+
+```elixir
+### Chunk start ###
+# Chunk type (stream identifier)
+"ff"
+# Chunk size in LE (6)
+"060000"
+# Chunk data ("sNaPpY" in ASCII)
+"734e61507059"
+
+### Chunk start ###
+# Chunk type (uncompressed data)
+"01"
+# Chunk size in LE (21)
+"150000"
+# CRC-32C checksum (4 bytes; little-endian)
+"cd11e7d5"
+# SSZ encoded payload (uncompressed)
+"3a03000000000000ffffffffffffffff0f"
+```
+
+## *SSZ*
+
+Decoding the payload with [simpleserialize.com](https://simpleserialize.com/), we find the received message:
+
+```json
+{
+  "seq_number": "826",
+  "attnets": "0xffffffffffffffff",
+  "syncnets": "0x0f"
+}
+```