Files
kamal/test/configuration/role_test.rb
Donal McBreen 8a41d15b69 Zero downtime deployment with cord file
When replacing a container currently we:
1. Boot the new container
2. Wait for it to become healthy
3. Stop the old container

Traefik will send requests to the old container until it notices that it
is unhealthy. But it may have stopped serving requests before that point
which can result in errors.

To get round that the new boot process is:

1. Create a directory with a single file on the host
2. Boot the new container, mounting the cord file into /tmp and
including a check for the file in the docker healthcheck
3. Wait for it to become healthy
4. Delete the healthcheck file ("cut the cord") for the old container
5. Wait for it to become unhealthy and give Traefik a couple of seconds
to notice
6. Stop the old container

The extra steps ensure that Traefik stops sending requests before the
old container is shutdown.
2023-09-06 14:35:30 +01:00

199 lines
6.3 KiB
Ruby

require "test_helper"
class ConfigurationRoleTest < ActiveSupport::TestCase
setup do
@deploy = {
service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
servers: [ "1.1.1.1", "1.1.1.2" ],
env: { "REDIS_URL" => "redis://x/y" }
}
@config = Kamal::Configuration.new(@deploy)
@deploy_with_roles = @deploy.dup.merge({
servers: {
"web" => [ "1.1.1.1", "1.1.1.2" ],
"workers" => {
"hosts" => [ "1.1.1.3", "1.1.1.4" ],
"cmd" => "bin/jobs",
"env" => {
"REDIS_URL" => "redis://a/b",
"WEB_CONCURRENCY" => 4
}
}
}
})
@config_with_roles = Kamal::Configuration.new(@deploy_with_roles)
end
test "hosts" do
assert_equal [ "1.1.1.1", "1.1.1.2" ], @config.role(:web).hosts
assert_equal [ "1.1.1.3", "1.1.1.4" ], @config_with_roles.role(:workers).hosts
end
test "cmd" do
assert_nil @config.role(:web).cmd
assert_equal "bin/jobs", @config_with_roles.role(:workers).cmd
end
test "label args" do
assert_equal [ "--label", "service=\"app\"", "--label", "role=\"workers\"" ], @config_with_roles.role(:workers).label_args
end
test "special label args for web" do
assert_equal [ "--label", "service=\"app\"", "--label", "role=\"web\"", "--label", "traefik.http.services.app-web.loadbalancer.server.scheme=\"http\"", "--label", "traefik.http.routers.app-web.rule=\"PathPrefix(\\`/\\`)\"", "--label", "traefik.http.middlewares.app-web-retry.retry.attempts=\"5\"", "--label", "traefik.http.middlewares.app-web-retry.retry.initialinterval=\"500ms\"", "--label", "traefik.http.routers.app-web.middlewares=\"app-web-retry@docker\"" ], @config.role(:web).label_args
end
test "custom labels" do
@deploy[:labels] = { "my.custom.label" => "50" }
assert_equal "50", @config.role(:web).labels["my.custom.label"]
end
test "custom labels via role specialization" do
@deploy_with_roles[:labels] = { "my.custom.label" => "50" }
@deploy_with_roles[:servers]["workers"]["labels"] = { "my.custom.label" => "70" }
assert_equal "70", @config_with_roles.role(:workers).labels["my.custom.label"]
end
test "overwriting default traefik label" do
@deploy[:labels] = { "traefik.http.routers.app-web.rule" => "\"Host(\\`example.com\\`) || (Host(\\`example.org\\`) && Path(\\`/traefik\\`))\"" }
assert_equal "\"Host(\\`example.com\\`) || (Host(\\`example.org\\`) && Path(\\`/traefik\\`))\"", @config.role(:web).labels["traefik.http.routers.app-web.rule"]
end
test "default traefik label on non-web role" do
config = Kamal::Configuration.new(@deploy_with_roles.tap { |c|
c[:servers]["beta"] = { "traefik" => "true", "hosts" => [ "1.1.1.5" ] }
})
assert_equal [ "--label", "service=\"app\"", "--label", "role=\"beta\"", "--label", "traefik.http.services.app-beta.loadbalancer.server.scheme=\"http\"", "--label", "traefik.http.routers.app-beta.rule=\"PathPrefix(\\`/\\`)\"", "--label", "traefik.http.middlewares.app-beta-retry.retry.attempts=\"5\"", "--label", "traefik.http.middlewares.app-beta-retry.retry.initialinterval=\"500ms\"", "--label", "traefik.http.routers.app-beta.middlewares=\"app-beta-retry@docker\"" ], config.role(:beta).label_args
end
test "env overwritten by role" do
assert_equal "redis://a/b", @config_with_roles.role(:workers).env["REDIS_URL"]
expected_env = <<~ENV
REDIS_URL=redis://a/b
WEB_CONCURRENCY=4
ENV
assert_equal expected_env, @config_with_roles.role(:workers).env_file
end
test "env args" do
assert_equal ["--env-file", ".kamal/env/roles/app-workers.env"], @config_with_roles.role(:workers).env_args
end
test "env secret overwritten by role" do
@deploy_with_roles[:env] = {
"clear" => {
"REDIS_URL" => "redis://a/b"
},
"secret" => [
"REDIS_PASSWORD"
]
}
@deploy_with_roles[:servers]["workers"]["env"] = {
"clear" => {
"REDIS_URL" => "redis://a/b",
"WEB_CONCURRENCY" => 4
},
"secret" => [
"DB_PASSWORD"
]
}
ENV["REDIS_PASSWORD"] = "secret456"
ENV["DB_PASSWORD"] = "secret&\"123"
expected = <<~ENV
REDIS_PASSWORD=secret456
DB_PASSWORD=secret&\"123
REDIS_URL=redis://a/b
WEB_CONCURRENCY=4
ENV
assert_equal expected, @config_with_roles.role(:workers).env_file
ensure
ENV["REDIS_PASSWORD"] = nil
ENV["DB_PASSWORD"] = nil
end
test "env secrets only in role" do
@deploy_with_roles[:servers]["workers"]["env"] = {
"clear" => {
"REDIS_URL" => "redis://a/b",
"WEB_CONCURRENCY" => 4
},
"secret" => [
"DB_PASSWORD"
]
}
ENV["DB_PASSWORD"] = "secret123"
expected = <<~ENV
DB_PASSWORD=secret123
REDIS_URL=redis://a/b
WEB_CONCURRENCY=4
ENV
assert_equal expected, @config_with_roles.role(:workers).env_file
ensure
ENV["DB_PASSWORD"] = nil
end
test "env secrets only at top level" do
@deploy_with_roles[:env] = {
"clear" => {
"REDIS_URL" => "redis://a/b"
},
"secret" => [
"REDIS_PASSWORD"
]
}
ENV["REDIS_PASSWORD"] = "secret456"
expected = <<~ENV
REDIS_PASSWORD=secret456
REDIS_URL=redis://a/b
WEB_CONCURRENCY=4
ENV
assert_equal expected, @config_with_roles.role(:workers).env_file
ensure
ENV["REDIS_PASSWORD"] = nil
end
test "host_env_directory" do
assert_equal ".kamal/env/roles", @config_with_roles.role(:workers).host_env_directory
end
test "host_env_file_path" do
assert_equal ".kamal/env/roles/app-workers.env", @config_with_roles.role(:workers).host_env_file_path
end
test "uses cord" do
assert @config_with_roles.role(:web).uses_cord?
assert !@config_with_roles.role(:workers).uses_cord?
end
test "cord host directory" do
assert_match %r{\$\(pwd\)/.kamal/cords/app-web-[0-9a-f]{32}}, @config_with_roles.role(:web).cord_host_directory
end
test "cord host file" do
assert_match %r{\$\(pwd\)/.kamal/cords/app-web-[0-9a-f]{32}/cord}, @config_with_roles.role(:web).cord_host_file
end
test "cord container directory" do
assert_equal "/tmp/kamal-cord", @config_with_roles.role(:web).cord_container_directory
end
test "cord container file" do
assert_equal "/tmp/kamal-cord/cord", @config_with_roles.role(:web).cord_container_file
end
end