From 5aab4801af620a9dc0459d8d51c1295092554d3a Mon Sep 17 00:00:00 2001
From: Ulrich Petri <ulo@ulo.pe>
Date: Mon, 31 Aug 2020 16:33:03 +0200
Subject: [PATCH] Split known servers

Depends-on: raiden-network/raiden-service-bundle#186
Related: #6443, #6212

This splits the known servers list into an 'active' and 'all' part.

The 'active' part is read by the Raiden client and used to select a
server to use.

The 'all' part is used by the RSB as the federation whitelist.

The purpose of this is to allow new servers to be added without making
the Raiden client immediately try to use them while they are not yet
ready.
---
 raiden/constants.py |  5 +++++
 raiden/settings.py  |  4 ++--
 raiden/utils/cli.py | 50 +++++++++++++++++++++++++++++++--------------
 3 files changed, 42 insertions(+), 17 deletions(-)

diff --git a/raiden/constants.py b/raiden/constants.py
index 52cf15520d..d736288758 100644
--- a/raiden/constants.py
+++ b/raiden/constants.py
@@ -86,6 +86,11 @@ class Capabilities(Enum):
     WEBRTC = "webRTC"
 
 
+class ServerListType(Enum):
+    ACTIVE_SERVERS = "active_servers"
+    ALL_SERVERS = "all_servers"
+
+
 # Set at 64 since parity's default is 64 and Geth's default is 128
 # TODO: Make this configurable. Since in parity this is also a configurable value
 STATE_PRUNING_AFTER_BLOCKS = 64
diff --git a/raiden/settings.py b/raiden/settings.py
index 2a75976191..65d1d6a68b 100644
--- a/raiden/settings.py
+++ b/raiden/settings.py
@@ -45,11 +45,11 @@
 DEFAULT_MATRIX_KNOWN_SERVERS = {
     Environment.PRODUCTION: (
         "https://raw.githubusercontent.com/raiden-network/raiden-service-bundle"
-        "/master/known_servers/known_servers.alderaan.yaml"
+        "/master/known_servers/known_servers-production-v1.2.0.json"
     ),
     Environment.DEVELOPMENT: (
         "https://raw.githubusercontent.com/raiden-network/raiden-service-bundle"
-        "/master/known_servers/known_servers.test.yaml"
+        "/master/known_servers/known_servers-development-v1.2.0.json"
     ),
 }
 
diff --git a/raiden/utils/cli.py b/raiden/utils/cli.py
index d59e5d4713..0cf287d510 100644
--- a/raiden/utils/cli.py
+++ b/raiden/utils/cli.py
@@ -1,9 +1,10 @@
 import errno
+import json
 import os
 import re
-import string
 from enum import EnumMeta
 from itertools import groupby
+from json.decoder import JSONDecodeError
 from pathlib import Path
 from string import Template
 from typing import Any, Callable, Dict, List, MutableMapping, Union
@@ -16,6 +17,7 @@
 from toml import TomlDecodeError, load
 from web3.gas_strategies.time_based import fast_gas_price_strategy
 
+from raiden.constants import ServerListType
 from raiden.exceptions import ConfigurationError, InvalidChecksummedAddress
 from raiden.network.rpc.middleware import faster_gas_price_strategy
 from raiden.utils.formatting import address_checksum_and_decode
@@ -423,13 +425,27 @@ def apply_config_file(
             cli_params[config_name_int] = config_value
 
 
-def get_matrix_servers(url: str) -> List[str]:
-    """Fetch a list of matrix servers from a text url
+def get_matrix_servers(
+    url: str, server_list_type: ServerListType = ServerListType.ACTIVE_SERVERS
+) -> List[str]:
+    """Fetch a list of matrix servers from a URL
 
-    '-' prefixes (YAML list) are cleaned. Comment lines /^\\s*#/ are ignored
+    The URL is expected to point to a JSON document of the following format::
 
-    url: url of a text file
-    returns: list of urls, default schema is https
+        {
+            "active_servers": [
+                "url1",
+                "url2",
+                ...
+            ],
+            "all_servers": [
+                "url1",
+                "url2",
+                ...
+            ]
+        }
+
+    Which of the two lists is returned is controlled by the ``server_list_type`` argument.
     """
     try:
         response = requests.get(url)
@@ -438,15 +454,19 @@ def get_matrix_servers(url: str) -> List[str]:
     except requests.RequestException as ex:
         raise RuntimeError(f"Could not fetch matrix servers list: {url!r} => {ex!r}") from ex
 
-    available_servers = []
-    for line in response.text.splitlines():
-        line = line.strip(string.whitespace + "-")
-        if line.startswith("#") or not line:
-            continue
-        if not line.startswith("http"):
-            line = "https://" + line  # default schema
-        available_servers.append(line)
-    return available_servers
+    try:
+        known_servers: Dict[str, List[str]] = json.loads(response.text)
+        msg = f"Unexpected format of known server list at {url}"
+        assert {type_.value for type_ in ServerListType} == known_servers.keys(), msg
+        active_servers = known_servers[server_list_type.value]
+    except (JSONDecodeError, AssertionError) as ex:
+        raise RuntimeError(
+            f"Could not process list of known matrix servers: {url!r} => {ex!r}"
+        ) from ex
+    return [
+        f"https://{server}" if not server.startswith("http") else server
+        for server in active_servers
+    ]
 
 
 ADDRESS_TYPE = AddressType()