Remove the 'changed tests' info from the build details API

Summary:
Data isn't exposed in the UI or used by any API clients I'm aware of, and at a spot-check wasn't
correct. But even if it were correct, it's taking up >1/3 of the build api endpoint for data we
aren't using, so seems best to remove it and look to our history if we want to revive.

Test Plan: Changes

Reviewers: naphat

Reviewed By: naphat

Subscribers: changesbot, anupc

Differential Revision: https://tails.corp.dropbox.com/D227879

changes/api/build_details.py

@@ -3,7 +3,6 @@
 from collections import defaultdict
 from flask_restful.reqparse import RequestParser
 from itertools import groupby
-from sqlalchemy import text
 from sqlalchemy.orm import contains_eager, joinedload, subqueryload_all
 from typing import List  # NOQA
 
@@ -25,95 +24,6 @@
 from changes.utils.originfinder import find_failure_origins
 
 
-def find_changed_tests(current_build, previous_build, limit=25):
-    current_job_ids = [j.id.hex for j in current_build.jobs]
-    previous_job_ids = [j.id.hex for j in previous_build.jobs]
-
-    if not (current_job_ids and previous_job_ids):
-        return []
-
-    current_job_clause = ', '.join(
-        ':c_job_id_%s' % i for i in range(len(current_job_ids))
-    )
-    previous_job_clause = ', '.join(
-        ':p_job_id_%s' % i for i in range(len(previous_job_ids))
-    )
-
-    params = {}
-    for idx, job_id in enumerate(current_job_ids):
-        params['c_job_id_%s' % idx] = job_id
-    for idx, job_id in enumerate(previous_job_ids):
-        params['p_job_id_%s' % idx] = job_id
-
-    # find all tests that have appeared in one job but not the other
-    # we have to build this query up manually as sqlalchemy doesnt support
-    # the FULL OUTER JOIN clause
-    query = """
-        SELECT c.id AS c_id,
-               p.id AS p_id
-        FROM (
-            SELECT label_sha, id
-            FROM test
-            WHERE job_id IN (%(current_job_clause)s)
-        ) as c
-        FULL OUTER JOIN (
-            SELECT label_sha, id
-            FROM test
-            WHERE job_id IN (%(previous_job_clause)s)
-        ) as p
-        ON c.label_sha = p.label_sha
-        WHERE (c.id IS NULL OR p.id IS NULL)
-    """ % {
-        'current_job_clause': current_job_clause,
-        'previous_job_clause': previous_job_clause
-    }
-
-    total = db.session.query(
-        'count'
-    ).from_statement(
-        text('SELECT COUNT(*) FROM (%s) as a' % (query,))
-    ).params(**params).scalar()
-
-    if not total:
-        return {
-            'total': 0,
-            'changes': [],
-        }
-
-    results = db.session.query(
-        'c_id', 'p_id'
-    ).from_statement(
-        text('%s LIMIT %d' % (query, limit))
-    ).params(**params)
-
-    all_test_ids = set()
-    for c_id, p_id in results:
-        if c_id:
-            all_test_ids.add(c_id)
-        else:
-            all_test_ids.add(p_id)
-
-    test_map = dict(
-        (t.id, t) for t in TestCase.query.filter(
-            TestCase.id.in_(all_test_ids),
-        ).options(
-            joinedload('job', innerjoin=True),
-        )
-    )
-
-    diff = []
-    for c_id, p_id in results:
-        if p_id:
-            diff.append(('-', test_map[p_id]))
-        else:
-            diff.append(('+', test_map[c_id]))
-
-    return {
-        'total': total,
-        'changes': sorted(diff, key=lambda x: (x[1].package, x[1].name)),
-    }
-
-
 def get_failure_reasons(build):
     from changes.buildfailures import registry
 
@@ -184,23 +94,6 @@ def get(self, build_id):
         if build is None:
             return '', 404
 
-        try:
-            most_recent_run = Build.query.filter(
-                Build.project == build.project,
-                Build.date_created < build.date_created,
-                Build.status == Status.finished,
-                Build.id != build.id,
-            ).join(
-                Source, Build.source_id == Source.id,
-            ).filter(
-                *build_type.get_any_commit_build_filters()
-            ).options(
-                contains_eager('source').joinedload('revision'),
-                joinedload('author'),
-            ).order_by(Build.date_created.desc())[0]
-        except IndexError:
-            most_recent_run = None
-
         jobs = list(Job.query.filter(
             Job.build_id == build.id,
         ))
@@ -230,12 +123,6 @@ def get(self, build_id):
         for test_failure in test_failures:
             test_failure.origin = failure_origins.get(test_failure)
 
-        # identify added/removed tests
-        if most_recent_run and build.status == Status.finished:
-            changed_tests = find_changed_tests(build, most_recent_run)
-        else:
-            changed_tests = []
-
         seen_by = list(User.query.join(
             BuildSeen, BuildSeen.user_id == User.id,
         ).filter(
@@ -261,7 +148,6 @@ def get(self, build_id):
                 'total': num_test_failures,
                 'tests': self.serialize(test_failures, extended_serializers),
             },
-            'testChanges': self.serialize(changed_tests, extended_serializers),
             'parents': self.serialize(get_parents_last_builds(build)),
         })
 

tests/changes/api/test_build_details.py

@@ -6,55 +6,7 @@
 from changes.models.event import Event
 from changes.models.failurereason import FailureReason
 from changes.models.itemstat import ItemStat
-from changes.models.test import TestCase
-from changes.testutils import APITestCase, TestCase as BaseTestCase
-from changes.api.build_details import find_changed_tests
-
-
-class FindChangedTestsTest(BaseTestCase):
-    def test_simple(self):
-        project = self.create_project()
-
-        previous_build = self.create_build(project)
-        previous_job = self.create_job(previous_build)
-
-        changed_test = TestCase(
-            job=previous_job,
-            project=previous_job.project,
-            name='unchanged test',
-        )
-        removed_test = TestCase(
-            job=previous_job,
-            project=previous_job.project,
-            name='removed test',
-        )
-        db.session.add(removed_test)
-        db.session.add(changed_test)
-
-        current_build = self.create_build(project)
-        current_job = self.create_job(current_build)
-        added_test = TestCase(
-            job=current_job,
-            project=current_job.project,
-            name='added test',
-        )
-
-        db.session.add(added_test)
-        db.session.add(TestCase(
-            job=current_job,
-            project=current_job.project,
-            name='unchanged test',
-        ))
-        db.session.commit()
-
-        results = find_changed_tests(current_build, previous_build)
-
-        assert results['total'] == 2
-
-        assert ('-', removed_test) in results['changes']
-        assert ('+', added_test) in results['changes']
-
-        assert len(results['changes']) == 2
+from changes.testutils import APITestCase
 
 
 class BuildDetailsTest(APITestCase):
@@ -99,7 +51,6 @@ def test_simple(self):
         assert data['seenBy'] == []
         assert data['testFailures']['total'] == 0
         assert data['testFailures']['tests'] == []
-        assert data['testChanges'] == []
         assert len(data['events']) == 1
         assert len(data['failures']) == 1
         assert data['failures'][0] == {