fix: the prometheus lables are inconsistent when using the same batch-processor instance on multi plugins

[zhendongcmss]

fix #6011

What this PR does / why we need it:

Pre-submission checklist:

• Did you explain what problem does this PR solve? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
• Is this PR backward compatible? If it is not backward compatible, please discuss on the mailing list first

[spacewander]

I just read this PR carefully.
Look like the master branch is also affected by this bug too. (I just read the code, have not reproduced it by myself)

I will try to reproduce it tomorrow.

[spacewander]

I can reproduce it in both 2.10 and master branch. What about submitting it to master first?

I reproduced it with t/plugin/prometheus3.t:

#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
BEGIN {
    if ($ENV{TEST_NGINX_CHECK_LEAK}) {
        $SkipReason = "unavailable for the hup tests";

    } else {
        $ENV{TEST_NGINX_USE_HUP} = 1;
        undef $ENV{TEST_NGINX_USE_STAP};
    }
}

use t::APISIX 'no_plan';

repeat_each(1);
no_long_string();
no_shuffle();
no_root_location();

add_block_preprocessor(sub {
    my ($block) = @_;

    if (!$block->request) {
        $block->set_value("request", "GET /t");
    }

    if ((!defined $block->error_log) && (!defined $block->no_error_log)) {
        $block->set_value("no_error_log", "[error]");
    }
});

run_tests;

__DATA__

=== TEST 1: use original etcd modified index
--- config
    location /t {
        content_by_lua_block {
            local t = require("lib.test_admin").test
            local code, body = t('/apisix/admin/plugin_configs/1',
                ngx.HTTP_PUT,
                [[{
                    "plugins": {
                        "prometheus":{}
                    }
                }]]
                )

            if code >= 300 then
                ngx.status = code
                ngx.say(body)
                return
            end

            local code, body = t('/apisix/admin/routes/1',
                ngx.HTTP_PUT,
                [[{
                    "plugin_config_id": 1,
                    "upstream": {
                        "nodes": {
                            "127.0.0.1:1980": 1
                        },
                        "type": "roundrobin"
                    },
                    "uri": "/hello"
                }]]
                )

            if code >= 300 then
                ngx.status = code
            end
            ngx.say(body)
        }
    }
--- response_body
passed



=== TEST 2: hit
--- pipelined_requests eval
["GET /hello", "GET /apisix/prometheus/metrics"]
--- error_code eval
[200, 200]



=== TEST 3: apisix_batch_process_entries, mess with global rules
--- config
    location /t {
        content_by_lua_block {
            local t = require("lib.test_admin").test
            local code, body = t('/apisix/admin/routes/1',
                 ngx.HTTP_PUT,
                 [[{
                        "plugins": {
                            "prometheus": {}
                        },
                        "upstream": {
                            "nodes": {
                                "127.0.0.1:1980": 1
                            },
                            "type": "roundrobin"
                        },
                        "uri": "/batch-process-metrics-aa"
                }]]
                )
            if code >= 300 then
                ngx.status = code
                ngx.say(body)
                return
            end

            local code, body = t('/apisix/admin/plugin_metadata/error-log-logger',
                ngx.HTTP_PUT,
                [[{
                    "tcp": {
                        "host": "127.0.0.1",
                        "port": 1999
                    },
                    "max_retry_count": 1000,
                    "level": "NOTICE"
                }]]
                )
            if code >= 300 then
                ngx.status = code
                ngx.say(body)
                return
            end

            local code, body = t('/apisix/admin/global_rules/1',
                 ngx.HTTP_PUT,
                 [[{
                        "plugins": {
                            "http-logger": {
                                "uri": "http://127.0.0.1:1979"
                            }
                        }
                }]]
                )

            if code >= 300 then
                ngx.status = code
            end
            ngx.say(body)
        }
    }
--- response_body
passed



=== TEST 4: check metrics
--- yaml_config
plugins:
  - error-log-logger
  - prometheus
  - http-logger
--- request
GET /t
--- config
    location /t {
        content_by_lua_block {
            local http = require "resty.http"
            local httpc = http.new()
            local uri = "http://127.0.0.1:" .. ngx.var.server_port
                        .. "/batch-process-metrics-aa"
            local res, err = httpc:request_uri(uri, {method = "GET"})
            if not res then
                ngx.say(err)
                return
            end

            ngx.sleep(2)
            local uri = "http://127.0.0.1:" .. ngx.var.server_port
                        .. "/apisix/prometheus/metrics"
            local res, err = httpc:request_uri(uri, {method = "GET"})
            if not res then
                ngx.say(err)
                return
            end
            ngx.say(res.body)
        }
    }
--- response_body_like eval
qr/apisix_batch_process_entries\{name="http logger",route_id="1",server_addr="127.0.0.1"\} \d+/

[spacewander]

What about providing a default value in

apisix/apisix/utils/batch-processor.lua

Line 138 in ddb9cd2

route_id = config.route_id,

?

[zhendongcmss]

I can reproduce it in both 2.10 and master branch. What about submitting it to master first?
Sure

[zhendongcmss]

What about providing a default value in

apisix/apisix/utils/batch-processor.lua

Line 138 in ddb9cd2

route_id = config.route_id,

?

I suggest that don't change the origin behavior. Sometimes we need to judge whether matching route accroding to toute_id.

[zhendongcmss]

I will raise a new pull request to master and close this pull request.
#6055