From 72a757059edc1fd12b532ade21b768b5ab1ba657 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pawe=C5=82=20Rozlach?= Date: Thu, 17 May 2018 20:09:23 +0200 Subject: [PATCH] Make server ids persistent across reloads (#586) --- config.py | 2 +- marathon_lb.py | 100 +++++++++++++++- requirements-dev.txt | 1 + tests/test_marathon_lb.py | 244 ++++++++++++++++++++++++++++---------- 4 files changed, 278 insertions(+), 69 deletions(-) diff --git a/config.py b/config.py index b9c63c3f..472f9e8b 100644 --- a/config.py +++ b/config.py @@ -692,7 +692,7 @@ def load(self): self.add_template( ConfigTemplate(name='BACKEND_SERVER_OPTIONS', value='''\ - server {serverName} {host_ipv4}:{port}{cookieOptions}\ + server {serverName} {host_ipv4}:{port} id {serverId}{cookieOptions}\ {healthCheckOptions}{otherOptions} ''', overridable=True, diff --git a/marathon_lb.py b/marathon_lb.py index b5f072ae..a117b08f 100755 --- a/marathon_lb.py +++ b/marathon_lb.py @@ -346,6 +346,93 @@ def mergeVhostTable(left, right): return result +def calculate_server_id(server_name, taken_server_ids): + """Calculate a stable server id given server name + + Calculates stable server id [1] for the given server name [2] + which has following properties: + * is unique/has not been assigned yet + * is an integer from the range 1-32767 + * is stable - i.e. calling this function repeatably with the same + server name must yield the same server id. + + THE STABILITY OF SERVER_ID IS GUARANTEED IF THE ORDER OF CALLS OF THIS + FUNCTION IS PRESERVED, I.E. THE BACKEND LIST IS SORTED BEFORE + PROCESSING + + [1] http://cbonte.github.io/haproxy-dconv/1.8/configuration.html#5.2-id + [2] http://cbonte.github.io/haproxy-dconv/1.8/configuration.html#5.2 + + Args: + server_name(str): the name of the given backend server + taken_server_ids(set): list of allready assigned server ids + + Returns: + An integer depicting the server ID + """ + if server_name == '' or server_name is None: + raise ValueError("Malformed server name: {}".format(server_name)) + + server_name_encoded = server_name.encode('utf-8') + server_name_shasum = hashlib.sha256(server_name_encoded).hexdigest() + + # The number 32767 is not coincidental. It is very important to notice + # in [1] that: + # * due to the use of atol() call [2], server id must not exceed the length + # of 'long int' on a given platform. According to [3] it is at + # least 32bits long so 32bits is a safe limit. + # * the atol() call returns `long int` which is assigned to puid var which + # int turn is `int`. As per [4]: + # + # ``` + # On a system where long is wider than int, if the value won't fit in an + # int, then the result of the conversion is implementation-defined. (Or, + # starting in C99, it can raise an implementation-defined signal, but I + # don't know of any compilers that actually do that.) What typically + # happens is that the high-order bits are discarded, but you shouldn't + # depend on that. (The rules are different for unsigned types; the result + # of converting a signed or unsigned integer to an unsigned type is well + # defined.) + # ``` + # + # So we need to assume that server id is 16 bit signed integer. Server id + # must be a positive number so this gives us at most 2**15-1 = 32767 + # possible server IDs. Beyond that there are dragons and the undefined + # behaviour of the C compiler ;) + # + # [1] https://github.com/haproxy/haproxy/blob/c55b88ece616afe0b28dc81eb39bad37b5f9c33f/src/server.c#L359-L388 # noqa: E501 + # [2] https://github.com/haproxy/haproxy/blob/c55b88ece616afe0b28dc81eb39bad37b5f9c33f/src/server.c#L368 # noqa: E501 + # [3] https://en.wikipedia.org/wiki/C_data_types + # [4] https://stackoverflow.com/a/13652624 + server_id = int(server_name_shasum, 16) % 32767 + + if server_id not in taken_server_ids and server_id > 0: + taken_server_ids.add(server_id) + return server_id + + # We try to solve the collisions by recursively calling + # calculate_backend_id() with the server name argument set to the initial + # server name plus the calculated `server_name_shasum` appended to it. + # This way we should get stable IDs during the next haproxy + # reconfiguration. The more backends there are the more likely the + # collisions will get. Initially the probability is 1/(2**15-1) * 100 = + # 0.003%. As the new_server_id gets longer the sha sum calculation will be + # getting more CPU-heavy and the number of SHA sum calculations per backend + # server will increase. Still - it is unlikely that we will hit the number + # backend server that will this approach a problem - the number of backend + # servers would need to be in the order of thousands. + new_server_name = "{0} {1}".format(server_name, server_name_shasum) + if server_id == 0: + msg_fmt = ("server id == 0 for `%s`, retrying with `%s`") + logger.info(msg_fmt, server_name, new_server_name) + else: + msg_fmt = ("server id collision for `%s`: `%d` was already assigned, " + "retrying with `%s`") + logger.info(msg_fmt, server_name, server_id, new_server_name) + + return calculate_server_id(new_server_name, taken_server_ids) + + def config(apps, groups, bind_http_https, ssl_certs, templater, haproxy_map=False, domain_map_array=[], app_map_array=[], config_file="/etc/haproxy/haproxy.cfg", @@ -550,6 +637,7 @@ def config(apps, groups, bind_http_https, ssl_certs, templater, do_backend_healthcheck_options_once = True key_func = attrgetter('host', 'port') + taken_server_ids = set() for backend_service_idx, backendServer\ in enumerate(sorted(app.backends, key=key_func)): if do_backend_healthcheck_options_once: @@ -597,6 +685,11 @@ def config(apps, groups, bind_http_https, ssl_certs, templater, shortHashedServerName = hashlib.sha1(serverName.encode()) \ .hexdigest()[:10] + # In order to keep the state of backend servers consistent between + # reloads, server IDs need to be stable. See + # calculate_backend_id()'s docstring to learn how it is achieved. + server_id = calculate_server_id(serverName, taken_server_ids) + server_health_check_options = None if app.healthCheck: template_server_healthcheck_options = None @@ -625,10 +718,11 @@ def config(apps, groups, bind_http_https, ssl_certs, templater, host_ipv4=backendServer.ip, port=backendServer.port, serverName=serverName, - cookieOptions=' check cookie ' + - shortHashedServerName if app.sticky else '', + serverId=server_id, + cookieOptions=' check cookie ' + shortHashedServerName + if app.sticky else '', healthCheckOptions=server_health_check_options - if server_health_check_options else '', + if server_health_check_options else '', otherOptions=' disabled' if backendServer.draining else '' ) diff --git a/requirements-dev.txt b/requirements-dev.txt index 1df9f917..b3d1e515 100644 --- a/requirements-dev.txt +++ b/requirements-dev.txt @@ -3,3 +3,4 @@ coverage flake8 mock nose +pytest==3.5.1 diff --git a/tests/test_marathon_lb.py b/tests/test_marathon_lb.py index 436bb9e3..8ba64648 100644 --- a/tests/test_marathon_lb.py +++ b/tests/test_marathon_lb.py @@ -2,6 +2,8 @@ import json import unittest import os +import string +import random import marathon_lb @@ -239,7 +241,7 @@ def test_config_simple_app(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -292,7 +294,7 @@ def test_config_healthcheck_command(self): backend nginx_10000 balance roundrobin mode tcp - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -353,7 +355,7 @@ def test_config_simple_app_vhost(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -416,7 +418,7 @@ def test_config_simple_app_multiple_vhost(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -478,7 +480,7 @@ def test_config_simple_app_vhost_and_redirect(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -542,7 +544,7 @@ def test_config_simple_app_multiple_vhost_and_redirect(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -615,7 +617,7 @@ def test_config_simple_app_vhost_with_auth(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -693,7 +695,7 @@ def test_config_simple_app_multiple_vhost_and_auth(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -769,7 +771,7 @@ def test_config_simple_app_vhost_with_path_and_auth(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -851,7 +853,7 @@ def test_config_simple_app_multiple_vhost_with_path_and_auth(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -915,7 +917,7 @@ def test_config_simple_app_vhost_with_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -982,7 +984,7 @@ def test_config_simple_app_multiple_vhost_with_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -1048,7 +1050,7 @@ def test_config_simple_app_vhost_with_path_and_redirect(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -1117,7 +1119,7 @@ def test_config_simple_app_multiple_vhost_with_path_and_redirect(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -1188,7 +1190,7 @@ def test_config_simple_app_multiple_vhost_path_redirect_hsts(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -1246,7 +1248,7 @@ def test_config_simple_app_balance(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -1303,7 +1305,7 @@ def strict_mode(self): option forwardfor http-request set-header X-Forwarded-Port %[dst_port] http-request add-header X-Forwarded-Proto https if { ssl_fc } - server 10_0_2_148_1565 10.0.2.148:1565 + server 10_0_2_148_1565 10.0.2.148:1565 id 16827 ''' self.assertMultiLineEqual(config, expected) @@ -1359,11 +1361,11 @@ def strict_mode(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server 10_0_1_147_25724 10.0.1.147:25724 check inter 3s fall 11 - server 10_0_6_25_16916 10.0.6.25:16916 check inter 3s fall 11 - server 10_0_6_25_23336 10.0.6.25:23336 check inter 3s fall 11 - server 10_0_6_25_31184 10.0.6.25:31184 check inter 3s fall 11 disabled -''' + server 10_0_1_147_25724 10.0.1.147:25724 id 9975 check inter 3s fall 11 + server 10_0_6_25_16916 10.0.6.25:16916 id 14685 check inter 3s fall 11 + server 10_0_6_25_23336 10.0.6.25:23336 id 14676 check inter 3s fall 11 + server 10_0_6_25_31184 10.0.6.25:31184 id 27565 check inter 3s fall 11 disabled +''' # noqa: E501 self.assertMultiLineEqual(config, expected) def test_config_simple_app_healthcheck_port(self): @@ -1419,8 +1421,8 @@ def test_config_simple_app_healthcheck_port(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 port 1024 -''' + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 port 1024 +''' # noqa: E501 self.assertMultiLineEqual(config, expected) def test_config_simple_app_healthcheck_port_using_another_portindex(self): @@ -1486,7 +1488,7 @@ def test_config_simple_app_healthcheck_port_using_another_portindex(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1024 192.0.2.1:1024 check inter 2s fall 11 port 1025 + server agent1_192_0_2_1_1024 192.0.2.1:1024 id 18199 check inter 2s fall 11 port 1025 backend nginx_10001 balance roundrobin @@ -1496,8 +1498,8 @@ def test_config_simple_app_healthcheck_port_using_another_portindex(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1025 192.0.2.1:1025 check inter 2s fall 11 -''' + server agent1_192_0_2_1_1025 192.0.2.1:1025 id 22260 check inter 2s fall 11 +''' # noqa: E501 self.assertMultiLineEqual(config, expected) def test_config_simple_app_healthcheck_port_diff_portindex_and_group(self): @@ -1563,7 +1565,7 @@ def test_config_simple_app_healthcheck_port_diff_portindex_and_group(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1024 192.0.2.1:1024 check inter 2s fall 11 port 1025 + server agent1_192_0_2_1_1024 192.0.2.1:1024 id 18199 check inter 2s fall 11 port 1025 backend nginx_10001 balance roundrobin @@ -1573,8 +1575,8 @@ def test_config_simple_app_healthcheck_port_diff_portindex_and_group(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1025 192.0.2.1:1025 check inter 2s fall 11 -''' + server agent1_192_0_2_1_1025 192.0.2.1:1025 id 22260 check inter 2s fall 11 +''' # noqa: E501 self.assertMultiLineEqual(config, expected) def test_config_simple_app_healthcheck_port_portindex_out_of_range(self): @@ -1647,7 +1649,7 @@ def test_config_simple_app_healthcheck_port_portindex_out_of_range(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1024 192.0.2.1:1024 check inter 2s fall 11 port 1024 + server agent1_192_0_2_1_1024 192.0.2.1:1024 id 18199 check inter 2s fall 11 port 1024 backend nginx_10001 balance roundrobin @@ -1657,8 +1659,8 @@ def test_config_simple_app_healthcheck_port_portindex_out_of_range(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1025 192.0.2.1:1025 check inter 2s fall 11 -''' + server agent1_192_0_2_1_1025 192.0.2.1:1025 id 22260 check inter 2s fall 11 +''' # noqa: E501 self.assertMultiLineEqual(config, expected) def test_config_simple_app_tcp_healthcheck(self): @@ -1715,7 +1717,7 @@ def test_config_simple_app_tcp_healthcheck(self): option forwardfor http-request set-header X-Forwarded-Port %[dst_port] http-request add-header X-Forwarded-Proto https if { ssl_fc } - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -1765,12 +1767,12 @@ def test_config_haproxy_group_fallback(self): backend nginx_10000 balance roundrobin mode tcp - server agent1_1_1_1_1_1024 1.1.1.1:1024 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 backend nginx_10001 balance roundrobin mode tcp - server agent1_1_1_1_1_1025 1.1.1.1:1025 + server agent1_1_1_1_1_1025 1.1.1.1:1025 id 19971 ''' self.assertMultiLineEqual(config, expected) @@ -1815,7 +1817,7 @@ def test_config_haproxy_group_per_service(self): backend nginx_10000 balance roundrobin mode tcp - server agent1_1_1_1_1_1024 1.1.1.1:1024 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 ''' self.assertMultiLineEqual(config, expected) @@ -1860,7 +1862,7 @@ def test_config_haproxy_group_hybrid(self): backend nginx_10001 balance roundrobin mode tcp - server agent1_1_1_1_1_1025 1.1.1.1:1025 + server agent1_1_1_1_1_1025 1.1.1.1:1025 id 19971 ''' self.assertMultiLineEqual(config, expected) @@ -1916,7 +1918,7 @@ def test_config_simple_app_proxypass(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } http-request set-header Host test.example.com reqirep "^([^ :]*)\ /test//?(.*)" "\\1\ /\\2" - server agent1_1_1_1_1_1024 1.1.1.1:1024 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 ''' self.assertMultiLineEqual(config, expected) @@ -1971,7 +1973,7 @@ def test_config_simple_app_revproxy(self): acl hdr_location res.hdr(Location) -m found rspirep "^Location: (https?://test.example.com(:[0-9]+)?)?(/.*)" "Location: \ /test if hdr_location" - server agent1_1_1_1_1_1024 1.1.1.1:1024 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 ''' self.assertMultiLineEqual(config, expected) @@ -2026,7 +2028,7 @@ def test_config_simple_app_redirect(self): acl is_root path -i / acl is_domain hdr(host) -i test.example.com redirect code 301 location /test if is_domain is_root - server agent1_1_1_1_1_1024 1.1.1.1:1024 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 ''' self.assertMultiLineEqual(config, expected) @@ -2070,7 +2072,7 @@ def test_config_simple_app_sticky(self): balance roundrobin mode tcp cookie mesosphere_server_id insert indirect nocache - server agent1_1_1_1_1_1024 1.1.1.1:1024 check cookie d6ad48c81f + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check cookie d6ad48c81f ''' self.assertMultiLineEqual(config, expected) @@ -2190,7 +2192,7 @@ def test_config_multi_app_multiple_vhost_with_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_1234 192.0.2.1:1234 check inter 2s fall 11 + server agent1_192_0_2_1_1234 192.0.2.1:1234 id 15582 check inter 2s fall 11 backend nginx1_10000 balance roundrobin @@ -2200,7 +2202,7 @@ def test_config_multi_app_multiple_vhost_with_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_2234 192.0.2.1:2234 check inter 2s fall 11 + server agent1_192_0_2_1_2234 192.0.2.1:2234 id 20338 check inter 2s fall 11 backend nginx2_10000 balance roundrobin @@ -2210,7 +2212,7 @@ def test_config_multi_app_multiple_vhost_with_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_3234 192.0.2.1:3234 check inter 2s fall 11 + server agent1_192_0_2_1_3234 192.0.2.1:3234 id 3933 check inter 2s fall 11 backend nginx3_10000 balance roundrobin @@ -2220,7 +2222,7 @@ def test_config_multi_app_multiple_vhost_with_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 10s - server agent1_192_0_2_1_4234 192.0.2.1:4234 check inter 2s fall 11 + server agent1_192_0_2_1_4234 192.0.2.1:4234 id 31229 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2297,7 +2299,7 @@ def test_config_haproxy_map(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 backend nginx_10000 balance roundrobin @@ -2307,7 +2309,7 @@ def test_config_haproxy_map(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 3s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2412,7 +2414,7 @@ def test_config_haproxy_map_hybrid(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 backend nginx_10000 balance roundrobin @@ -2422,7 +2424,7 @@ def test_config_haproxy_map_hybrid(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 3s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2539,7 +2541,7 @@ def test_config_haproxy_map_auth_noauth(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 3s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 3s fall 11 backend nginx2_10001 balance roundrobin @@ -2549,7 +2551,7 @@ def test_config_haproxy_map_auth_noauth(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2655,7 +2657,7 @@ def test_config_haproxy_map_hybrid_with_vhost_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 backend nginx_10000 balance roundrobin @@ -2665,7 +2667,7 @@ def test_config_haproxy_map_hybrid_with_vhost_path(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 3s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2766,7 +2768,7 @@ def test_config_haproxy_map_hybrid_httptohttps_redirect(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 backend nginx_10000 balance roundrobin @@ -2776,7 +2778,7 @@ def test_config_haproxy_map_hybrid_httptohttps_redirect(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 3s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2865,7 +2867,7 @@ def test_config_simple_app_long_backend_proxypass(self): reqirep "^([^ :]*)\ ''' + app.proxypath + '''/?(.*)" "\\1\ /\\2" option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2925,7 +2927,7 @@ def test_config_simple_app_proxypass_health_check(self): reqirep "^([^ :]*)\ /proxy/path/?(.*)" "\\1\ /\\2" option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -2986,7 +2988,7 @@ def test_config_simple_app_revproxy_health_check(self): "Location: /proxy/path if hdr_location" option httpchk GET / timeout check 10s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 2s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 2s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -3057,7 +3059,7 @@ def test_strict_mode_on_and_off(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -3131,7 +3133,7 @@ def test_backend_disabled_and_enablede(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -3305,7 +3307,7 @@ def test_group_https_by_vhost(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent4_4_4_4_4_1026 4.4.4.4:1026 check inter 3s fall 11 + server agent4_4_4_4_4_1026 4.4.4.4:1026 id 18496 check inter 3s fall 11 backend nginx1_10000 balance roundrobin @@ -3315,7 +3317,7 @@ def test_group_https_by_vhost(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent1_1_1_1_1_1024 1.1.1.1:1024 check inter 3s fall 11 + server agent1_1_1_1_1_1024 1.1.1.1:1024 id 28363 check inter 3s fall 11 backend nginx2_10001 balance roundrobin @@ -3325,7 +3327,7 @@ def test_group_https_by_vhost(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent2_2_2_2_2_1025 2.2.2.2:1025 check inter 3s fall 11 + server agent2_2_2_2_2_1025 2.2.2.2:1025 id 5918 check inter 3s fall 11 backend nginx3_10002 balance roundrobin @@ -3335,7 +3337,7 @@ def test_group_https_by_vhost(self): http-request add-header X-Forwarded-Proto https if { ssl_fc } option httpchk GET / timeout check 15s - server agent3_3_3_3_3_1026 3.3.3.3:1026 check inter 3s fall 11 + server agent3_3_3_3_3_1026 3.3.3.3:1026 id 638 check inter 3s fall 11 ''' self.assertMultiLineEqual(config, expected) @@ -3377,3 +3379,115 @@ def test_json_nested_null_dict_list(self): data = marathon_lb.load_json(json_value) expected = ['k1', {'k3': ['k4', {}]}, 'k6'] self.assertEquals(data, expected) + + +class TestServerIdGeneration(unittest.TestCase): + @staticmethod + def _randomword(length): + letters = string.ascii_lowercase + return ''.join(random.choice(letters) for i in range(length)) + + def test_if_server_id_is_generated(self): + test_cases = [ + ('0', 17068), + ('1', 25733), + ('a', 25929), + ('10_0_6_25_23336', 14676), + ] + taken_server_ids = set() + for i in range(0, len(test_cases)): + self.assertEqual( + marathon_lb.calculate_server_id( + test_cases[i][0], taken_server_ids), + test_cases[i][1]) + + self.assertEqual(set([x[1] for x in test_cases]), taken_server_ids) + + def test_if_server_id_collisions_are_handled_synthetic(self): + # All the test cases here generate the same server id in the first + # iteration. The idea is that if the collisions are handled, it will + # still result in different server ids returned by the + # calculate_server_id() function. + test_cases = [ + ('yftjqzplpu', 28876), + ('ttccbfrdhi', 7893), + ('ilvparharq', 22002), + ('gpagkxfzou', 21805), + ('dcsfcvfolh', 20892), + ('tsqkugaath', 25675), + ] + taken_server_ids = set() + for i in range(0, len(test_cases)): + self.assertEqual( + marathon_lb.calculate_server_id( + test_cases[i][0], taken_server_ids), + test_cases[i][1]) + + self.assertEqual(set([x[1] for x in test_cases]), taken_server_ids) + + def test_if_server_id_collisions_are_handled_accurate(self): + num_server_names = 30000 + # The approach of this test is more real-life like: we generate + # num_server_names unique server names. If num_server_names is close to + # the limit (i.e. 32767), collisions need to be handled gracefull in + # order to generate all the server id. + # Haproxy is most probably incapable of handling so many + # backend servers but still - passing this test should prove that we + # have enough headroom to handle all the real life scenarios. + taken_server_ids = set() + for i in range(0, num_server_names): + marathon_lb.calculate_server_id( + self._randomword(20), taken_server_ids) + + self.assertEqual(len(taken_server_ids), num_server_names) + + def test_if_server_id_is_always_nonzero(self): + # This test assumes some knowledge of the internal implementation of + # the tested function, as it uses pre-calculated strings which normally + # would result in server_id==0. Unfortunatelly there is no easy way to + # test it more reliably - i.e without making assumptions about the + # input. + test_cases = [ + ('uudnntiqtd', 26825), + ('rghtavdepy', 5030), + ('ofdsehlvjo', 26512), + ('adwquoyjfl', 24165), + ('oebmwvpofe', 11608), + ] + for i in range(0, len(test_cases)): + self.assertEqual( + marathon_lb.calculate_server_id(test_cases[i][0], set()), + test_cases[i][1]) + + def test_service_name_sequence_to_service_id_sequence_stability(self): + num_server_names = 1000 + # This test checks if given the same sequence of string of + # service_names the resulting sequence of service_ids will always be + # the same + + server_ids = dict() + for i in range(0, num_server_names): + sn = self._randomword(20) + server_ids[sn] = list() + + for i in range(0, 3): + tmp_set = set() + for sn in server_ids: + server_ids[sn].append( + marathon_lb.calculate_server_id(sn, tmp_set)) + + for sn in server_ids: + # Compare first and the second server_id for the given server + # name: + self.assertEqual(server_ids[sn][0], server_ids[sn][1]) + # Compare second and the third server_id for the given server + # name: + self.assertEqual(server_ids[sn][1], server_ids[sn][2]) + + def test_if_server_name_cant_be_empty_string(self): + with self.assertRaises(ValueError): + marathon_lb.calculate_server_id('', set()) + + def test_if_server_name_cant_be_none(self): + with self.assertRaises(ValueError): + marathon_lb.calculate_server_id(None, set())