chore(test): upgrade the mock collector and drop the seed workaround

The pinned mock-collector image dated from October 2022, 13 commits behind
the tool's master. Move it to c6b91a0e, which carries the fix for the
first-insert race in SegmentItems/LogItems
(apache/skywalking-agent-test-tool#65): when two processes reported their
first segment for the same service name concurrently, the collector
silently dropped one while both reporters got HTTP 200.

sw_fork_support worked around that race by seeding the service name with a
parent-only /ping request and waiting for the collector to register it
before triggering the concurrent parent/child reports. The collector no
longer needs the help, so the endpoint, the seed step and the extra
expected segment are gone and the test is back to asserting exactly the
cross-fork trace it is about.

The upgrade also picks up the validator changes made since 2022 (stricter
span validation in #53, LogAssert ordering in #59, string operators in
#49, protocol update in #63), so the full plugin matrix on CI is the real
verification here.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: wu-sheng

tests/plugin/docker-compose.base.yml

@@ -20,7 +20,7 @@ version: '2.1'
 
 services:
   collector:
-    image: ghcr.io/apache/skywalking-agent-test-tool/mock-collector:7f20775e0631356c4823d9372b09d653db0e6540
+    image: ghcr.io/apache/skywalking-agent-test-tool/mock-collector:c6b91a0eaef16d427268e9806d5df65949e2a9bf
     ports:
       - 19876:19876
       - 12800:12800

tests/plugin/web/sw_fork_support/expected.data.yml

@@ -17,27 +17,8 @@
 
 segmentItems:
   - serviceName: provider
-    segmentSize: 3
+    segmentSize: 2
     segments:
-      - segmentId: not null
-        spans:
-          - operationName: /ping
-            parentSpanId: -1
-            spanId: 0
-            spanLayer: Http
-            tags:
-              - key: http.method
-                value: GET
-              - key: http.url
-                value: http://0.0.0.0:9090/ping
-              - key: http.status_code
-                value: '200'
-            startTime: gt 0
-            endTime: gt 0
-            componentId: 7001
-            spanType: Entry
-            peer: not null
-            skipAnalysis: false
       - segmentId: not null
         spans:
           - operationName: /users

tests/plugin/web/sw_fork_support/services/app.py

@@ -50,14 +50,6 @@ def users():
 
         frontend = Flask('frontend')
 
-        # readiness/warm-up endpoint: its segment arrives alone and seeds the service name
-        # in the mock collector, whose first-insert for a service is not concurrency-safe
-        # (SegmentItems.addSegmentItem check-then-act) — the parent and child later report
-        # their /users segments concurrently under the same service name
-        @frontend.route('/ping', methods=['GET'])
-        def ping():
-            return jsonify({'song': 'Despacito'})
-
         @frontend.route('/users', methods=['GET'])
         def call_backend():
             res = requests.get('http://127.0.0.1:9091/users', timeout=5)

tests/plugin/web/sw_fork_support/test_fork_support.py

@@ -14,7 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-import time
 from typing import Callable
 
 import pytest
@@ -26,10 +25,7 @@
 @pytest.fixture
 def prepare():
     # type: () -> Callable
-    # /ping (parent-only) also seeds the service name in the mock collector before the
-    # parent and child post their /users segments concurrently: the collector's very first
-    # insert for a service name is not concurrency-safe and can silently drop one segment
-    return lambda *_: requests.get('http://0.0.0.0:9090/ping', timeout=5).raise_for_status()
+    return lambda *_: requests.get('http://0.0.0.0:9090/users', timeout=5).raise_for_status()
 
 
 class TestPlugin(TestPluginBase):
@@ -44,19 +40,6 @@ class TestPlugin(TestPluginBase):
 
     @pytest.mark.parametrize('version', ['grpcio>=1.83'])
     def test_plugin(self, docker_compose, version):
-        # the /ping seed segment must be REGISTERED by the collector before /users makes
-        # the parent and child report concurrently, otherwise all three segments can be
-        # in flight together and the collector's first-insert race still drops one
-        for _ in range(30):
-            if '/ping' in requests.get('http://localhost:12800/receiveData', timeout=5).text:
-                break
-            time.sleep(1)
-        else:
-            raise Exception('the /ping seed segment never reached the collector')
-
-        response = requests.get('http://0.0.0.0:9090/users', timeout=5)
-        assert response.status_code == 200
-
         self.validate()
 
         stdout, stderr = docker_compose.get_logs()