feat(python): add btc get-descriptor command

python/src/trezorlib/btc.py

@@ -66,6 +66,7 @@ def get_public_node(
     show_display=False,
     coin_name=None,
     script_type=messages.InputScriptType.SPENDADDRESS,
+    ignore_xpub_magic=False,
 ):
     return client.call(
         messages.GetPublicKey(
@@ -74,6 +75,7 @@ def get_public_node(
             show_display=show_display,
             coin_name=coin_name,
             script_type=script_type,
+            ignore_xpub_magic=ignore_xpub_magic,
         )
     )
 

python/src/trezorlib/cli/btc.py

@@ -27,12 +27,18 @@ INPUT_SCRIPTS = {
     "address": messages.InputScriptType.SPENDADDRESS,
     "segwit": messages.InputScriptType.SPENDWITNESS,
     "p2shsegwit": messages.InputScriptType.SPENDP2SHWITNESS,
+    "pkh": messages.InputScriptType.SPENDADDRESS,
+    "wpkh": messages.InputScriptType.SPENDWITNESS,
+    "sh-wpkh": messages.InputScriptType.SPENDP2SHWITNESS,
 }
 
 OUTPUT_SCRIPTS = {
     "address": messages.OutputScriptType.PAYTOADDRESS,
     "segwit": messages.OutputScriptType.PAYTOWITNESS,
     "p2shsegwit": messages.OutputScriptType.PAYTOP2SHWITNESS,
+    "pkh": messages.OutputScriptType.PAYTOADDRESS,
+    "wpkh": messages.OutputScriptType.PAYTOWITNESS,
+    "sh-wpkh": messages.OutputScriptType.PAYTOP2SHWITNESS,
 }
 
 DEFAULT_COIN = "Bitcoin"
@@ -184,6 +190,63 @@ def get_public_node(client, coin, address, curve, script_type, show_display):
     }
 
 
+def _get_descriptor(client, coin, account, script_type, show_display):
+    coin = coin or DEFAULT_COIN
+    if script_type == messages.InputScriptType.SPENDADDRESS:
+        acc_type = 44
+        fmt = "pkh({})"
+    elif script_type == messages.InputScriptType.SPENDP2SHWITNESS:
+        acc_type = 49
+        fmt = "sh(wpkh({}))"
+    elif script_type == messages.InputScriptType.SPENDWITNESS:
+        acc_type = 84
+        fmt = "wpkh({})"
+    else:
+        raise ValueError("Unsupported account type")
+
+    if coin is None or coin == "Bitcoin":
+        coin_type = 0
+    elif coin == "Testnet":
+        coin_type = 1
+    else:
+        raise ValueError("Unsupported coin")
+
+    path = f"m/{acc_type}'/{coin_type}'/{account}'"
+    n = tools.parse_path(path)
+    pub = btc.get_public_node(
+        client,
+        n,
+        show_display=show_display,
+        coin_name=coin,
+        script_type=script_type,
+        ignore_xpub_magic=True,
+    )
+
+    fingerprint = pub.root_fingerprint if pub.root_fingerprint is not None else 0
+    external = f"[{fingerprint:08x}{path[1:]}]{pub.xpub}/0/*"
+    internal = f"[{fingerprint:08x}{path[1:]}]{pub.xpub}/1/*"
+    return fmt.format(external), fmt.format(internal)
+
+
+@cli.command()
+@click.option("-c", "--coin")
+@click.option(
+    "-n", "--account", required=True, type=int, help="account index (0 = first account)"
+)
+@click.option("-t", "--script-type", type=ChoiceType(INPUT_SCRIPTS), default="address")
+@click.option("-d", "--show-display", is_flag=True)
+@with_client
+def get_descriptor(client, coin, account, script_type, show_display):
+    """Get descriptor of given account."""
+    try:
+        ds = _get_descriptor(client, coin, account, script_type, show_display)
+        click.echo()
+        for d in ds:
+            click.echo(d)
+    except ValueError as e:
+        raise click.ClickException(e.msg)
+
+
 #
 # Signing functions
 #