1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
# frozen_string_literal: true
require 'spec_helper'
RSpec.describe Postgresql::ReplicationSlot do
it { is_expected.to be_a Gitlab::Database::SharedModel }
describe '.in_use?' do
it 'returns true when replication slots are present' do
expect(described_class).to receive(:exists?).and_return(true)
expect(described_class.in_use?).to be_truthy
end
it 'returns false when replication slots are not present' do
expect(described_class.in_use?).to be_falsey
end
it 'returns false if the existence check is invalid' do
expect(described_class).to receive(:exists?).and_raise(ActiveRecord::StatementInvalid.new('PG::FeatureNotSupported'))
expect(described_class.in_use?).to be_falsey
end
end
describe '.lag_too_great?' do
before do
expect(described_class).to receive(:in_use?).and_return(true)
end
it 'does not raise an exception' do
expect { described_class.lag_too_great? }.not_to raise_error
end
it 'returns true when replication lag is too great' do
expect(described_class)
.to receive(:pluck)
.and_return([125.megabytes])
expect(described_class.lag_too_great?).to eq(true)
end
it 'returns false when more than one replicas is up to date enough' do
expect(described_class)
.to receive(:pluck)
.and_return([125.megabytes, 0.megabytes, 0.megabytes])
expect(described_class.lag_too_great?).to eq(false)
end
it 'returns false when replication lag is not too great' do
expect(described_class)
.to receive(:pluck)
.and_return([0.megabytes])
expect(described_class.lag_too_great?).to eq(false)
end
it 'returns false when there is a nil replication lag' do
expect(described_class)
.to receive(:pluck)
.and_return([0.megabytes, nil])
expect(described_class.lag_too_great?).to eq(false)
end
end
describe '#max_replication_slots' do
it 'returns the maximum number of replication slots' do
expect(described_class.max_replication_slots).to be >= 0
end
end
context 'with enough slots available' do
skip_examples = described_class.max_replication_slots <= described_class.count
before_all do
skip('max_replication_slots too small') if skip_examples
@current_slot_count = described_class
.connection
.select_value("SELECT COUNT(*) FROM pg_replication_slots")
@current_unused_count = described_class
.connection
.select_value("SELECT COUNT(*) FROM pg_replication_slots WHERE active = 'f';")
described_class
.connection
.execute("SELECT * FROM pg_create_physical_replication_slot('test_slot');")
end
after(:all) do
unless skip_examples
described_class
.connection
.execute("SELECT pg_drop_replication_slot('test_slot');")
end
end
describe '#slots_count' do
it 'returns the number of replication slots' do
expect(described_class.count).to eq(@current_slot_count + 1)
end
end
describe '#unused_slots_count' do
it 'returns the number of unused replication slots' do
expect(described_class.unused_slots_count).to eq(@current_unused_count + 1)
end
end
describe '#max_retained_wal' do
it 'returns the retained WAL size' do
expect(described_class.max_retained_wal).not_to be_nil
end
end
describe '#slots_retained_bytes' do
it 'returns the number of retained bytes' do
slot = described_class.slots_retained_bytes.find { |x| x['slot_name'] == 'test_slot' }
expect(slot).not_to be_nil
expect(slot['retained_bytes']).to be_nil
end
end
end
end
|
