• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1"""
2In a few words: some devices in Mesa CI has problematic serial connection, they
3may hang (become silent) intermittently. Every time it hangs for minutes, the
4job is retried, causing delays in the overall pipeline executing, ultimately
5blocking legit MRs to merge.
6
7To reduce reliance on UART, we explored LAVA features, such as running docker
8containers as a test alongside the DUT one, to be able to create an SSH server
9in the DUT the earliest possible and an SSH client in a docker container, to
10establish a SSH session between both, allowing the console output to be passed
11via SSH pseudo terminal, instead of relying in the error-prone UART.
12
13In more detail, we aim to use "export -p" to share the initial boot environment
14with SSH LAVA test-cases.
15The "init-stage1.sh" script handles tasks such as system mounting and network
16setup, which are necessary for allocating a pseudo-terminal under "/dev/pts".
17Although these chores are not required for establishing an SSH session, they are
18essential for proper functionality to the target script given by HWCI_SCRIPT
19environment variable.
20
21Therefore, we have divided the job definition into four parts:
22
231. [DUT] Logging in to DUT and run the SSH server with root access.
242. [DUT] Running the "init-stage1.sh" script for the first SSH test case.
253. [DUT] Export the first boot environment to `/dut-env-vars.sh` file.
264. [SSH] Enabling the pseudo-terminal for colors and running the "init-stage2.sh"
27script after sourcing "dut-env-vars.sh" again for the second SSH test case.
28"""
29
30
31import re
32from typing import TYPE_CHECKING, Any, Iterable
33
34from ruamel.yaml.scalarstring import LiteralScalarString
35
36from .constants import NUMBER_OF_ATTEMPTS_LAVA_BOOT
37
38if TYPE_CHECKING:
39    from ..lava_job_submitter import LAVAJobSubmitter
40
41# Very early SSH server setup. Uses /dut_ready file to flag it is done.
42SSH_SERVER_COMMANDS = {
43    "auto_login": {
44        "login_commands": [
45            "dropbear -R -B",
46            "touch /dut_ready",
47        ],
48        "login_prompt": "ogin:",
49        # To login as root, the username should be empty
50        "username": "",
51    }
52}
53
54# TODO: Extract this inline script to a shell file, like we do with
55# init-stage[12].sh
56# The current way is difficult to maintain because one has to deal with escaping
57# characters for both Python and the resulting job definition YAML.
58# Plus, it always good to lint bash scripts with shellcheck.
59DOCKER_COMMANDS = [
60    """set -ex
61timeout 1m bash << EOF
62while [ -z "$(lava-target-ip)" ]; do
63    echo Waiting for DUT to join LAN;
64    sleep 1;
65done
66EOF
67
68ping -c 5 -w 60 $(lava-target-ip)
69
70lava_ssh_test_case() {
71    set -x
72    local test_case="${1}"
73    shift
74    lava-test-case \"${test_case}\" --shell \\
75        ssh ${SSH_PTY_ARGS:--T} \\
76        -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null \\
77        root@$(lava-target-ip) \"${@}\"
78}""",
79]
80
81
82def to_yaml_block(steps_array: Iterable[str], escape_vars=[]) -> LiteralScalarString:
83    def escape_envvar(match):
84        return "\\" + match.group(0)
85
86    filtered_array = [s for s in steps_array if s.strip() and not s.startswith("#")]
87    final_str = "\n".join(filtered_array)
88
89    for escape_var in escape_vars:
90        # Find env vars and add '\\' before them
91        final_str = re.sub(rf"\${escape_var}*", escape_envvar, final_str)
92    return LiteralScalarString(final_str)
93
94
95def generate_dut_test(args: "LAVAJobSubmitter", first_stage_steps: list[str]) -> dict[str, Any]:
96    # Commands executed on DUT.
97    # Trying to execute the minimal number of commands, because the console data is
98    # retrieved via UART, which is hang-prone in some devices.
99    return {
100        "namespace": "dut",
101        "definitions": [
102            {
103                "from": "inline",
104                "name": "setup-ssh-server",
105                "path": "inline-setup-ssh-server",
106                "repository": {
107                    "metadata": {
108                        "format": "Lava-Test Test Definition 1.0",
109                        "name": "dut-env-export",
110                    },
111                    "run": {
112                        "steps": [
113                            to_yaml_block(first_stage_steps),
114                            "export -p > /dut-env-vars.sh",  # Exporting the first boot environment
115                        ],
116                    },
117                },
118            }
119        ],
120    }
121
122
123def generate_docker_test(
124    args: "LAVAJobSubmitter", artifact_download_steps: list[str]
125) -> dict[str, Any]:
126    # This is a growing list of commands that will be executed by the docker
127    # guest, which will be the SSH client.
128    docker_commands = []
129
130    # LAVA test wrapping Mesa CI job in a SSH session.
131    init_stages_test = {
132        "namespace": "container",
133        "timeout": {"minutes": args.job_timeout_min},
134        "failure_retry": 3,
135        "definitions": [
136            {
137                "name": "docker_ssh_client",
138                "from": "inline",
139                "path": "inline/docker_ssh_client.yaml",
140                "repository": {
141                    "metadata": {
142                        "name": "mesa",
143                        "description": "Mesa test plan",
144                        "format": "Lava-Test Test Definition 1.0",
145                    },
146                    "run": {"steps": docker_commands},
147                },
148            }
149        ],
150        "docker": {
151            "image": args.ssh_client_image,
152        },
153    }
154
155    docker_commands += [
156        to_yaml_block(DOCKER_COMMANDS, escape_vars=["LAVA_TARGET_IP"]),
157        "lava_ssh_test_case 'wait_for_dut_login' << EOF",
158        "while [ ! -e /dut_ready ]; do sleep 1; done;",
159        "EOF",
160        to_yaml_block(
161            (
162                "lava_ssh_test_case 'artifact_download' 'bash --' << EOF",
163                "source /dut-env-vars.sh",
164                *artifact_download_steps,
165                "EOF",
166            )
167        ),
168        "export SSH_PTY_ARGS=-tt",
169        # Putting CI_JOB name as the testcase name, it may help LAVA farm
170        # maintainers with monitoring
171        f"lava_ssh_test_case '{args.project_name}_{args.mesa_job_name}' "
172        # Changing directory to /, as the HWCI_SCRIPT expects that
173        "'\"cd / && /init-stage2.sh\"'",
174    ]
175
176    return init_stages_test
177
178
179def wrap_final_deploy_action(final_deploy_action: dict):
180    wrap = {
181        "namespace": "dut",
182        "failure_retry": NUMBER_OF_ATTEMPTS_LAVA_BOOT,
183        "timeout": {"minutes": 10},
184    }
185
186    final_deploy_action.update(wrap)
187
188
189def wrap_boot_action(boot_action: dict):
190    wrap = {
191        "namespace": "dut",
192        "failure_retry": NUMBER_OF_ATTEMPTS_LAVA_BOOT,
193        **SSH_SERVER_COMMANDS,
194    }
195
196    boot_action.update(wrap)
197