tsiry-sandratraina.com
A convenient CLI tool to quickly spin up DragonflyBSD virtual machines using QEMU with sensible defaults.
Refactor stop command to improve error handling and control flow using Effect
+80
-80
src/subcommands/stop.ts
+80
-80
src/subcommands/stop.ts
···
1
import _ from "@es-toolkit/es-toolkit/compat";
2
import chalk from "chalk";
3
-
import { Effect, pipe } from "effect";
4
import type { VirtualMachine } from "../db.ts";
5
-
import { getInstanceStateOrFail, updateInstanceState } from "../state.ts";
6
7
-
const logStoppingMessage = (vm: VirtualMachine) =>
8
Effect.sync(() => {
9
console.log(
10
`Stopping virtual machine ${chalk.greenBright(vm.name)} (ID: ${
···
13
);
14
});
15
16
-
const buildKillCommand = (vm: VirtualMachine) => ({
17
-
command: vm.bridge ? "sudo" : "kill",
18
-
args: [
19
-
..._.compact([vm.bridge && "kill"]),
20
-
"-TERM",
21
-
vm.pid.toString(),
22
-
],
23
-
});
24
-
25
-
const executeKillCommand = (vm: VirtualMachine) => {
26
-
const { command, args } = buildKillCommand(vm);
27
-
28
-
return Effect.tryPromise({
29
try: async () => {
30
-
const cmd = new Deno.Command(command, {
31
-
args,
32
stdin: "inherit",
33
stdout: "inherit",
34
stderr: "inherit",
35
});
36
37
-
return await cmd.spawn().status;
38
},
39
-
catch: (cause) => new Error(`Failed to execute kill command: ${cause}`),
40
-
});
41
-
};
42
-
43
-
const validateKillResult = (vm: VirtualMachine, status: Deno.CommandStatus) =>
44
-
Effect.sync(() => {
45
-
if (!status.success) {
46
-
throw new Error(`Failed to stop virtual machine ${vm.name}`);
47
-
}
48
-
return vm;
49
-
});
50
51
-
const markInstanceAsStopped = (vm: VirtualMachine) =>
52
-
updateInstanceState(vm.name, "STOPPED");
53
54
-
const logStopSuccess = (vm: VirtualMachine) =>
55
Effect.sync(() => {
56
console.log(`Virtual machine ${chalk.greenBright(vm.name)} stopped.`);
57
});
58
59
-
const stopVirtualMachineProcess = (vm: VirtualMachine) =>
60
-
pipe(
61
-
executeKillCommand(vm),
62
-
Effect.flatMap((status) => validateKillResult(vm, status)),
63
-
Effect.flatMap(() => markInstanceAsStopped(vm)),
64
-
Effect.flatMap(() => logStopSuccess(vm)),
65
-
);
66
67
-
const stopVirtualMachine = (name: string) =>
68
pipe(
69
-
getInstanceStateOrFail(name),
70
-
Effect.flatMap((vm) =>
71
-
pipe(
72
-
logStoppingMessage(vm),
73
-
Effect.flatMap(() => stopVirtualMachineProcess(vm)),
74
-
)
75
-
),
76
);
77
78
export default async function (name: string) {
79
-
const program = pipe(
80
-
stopVirtualMachine(name),
81
-
Effect.catchTags({
82
-
InstanceNotFoundError: (_error) =>
83
-
Effect.sync(() => {
84
-
console.error(
85
-
`Virtual machine with name or ID ${
86
-
chalk.greenBright(name)
87
-
} not found.`,
88
-
);
89
-
Deno.exit(1);
90
-
}),
91
-
DatabaseQueryError: (error) =>
92
-
Effect.sync(() => {
93
-
console.error(`Database error: ${error.message}`);
94
-
Deno.exit(1);
95
-
}),
96
-
DatabaseUpdateError: (error) =>
97
-
Effect.sync(() => {
98
-
console.error(`Failed to update database: ${error.message}`);
99
-
Deno.exit(1);
100
-
}),
101
-
}),
102
-
Effect.catchAll((error) =>
103
-
Effect.sync(() => {
104
-
console.error(`Error: ${error.message}`);
105
-
Deno.exit(1);
106
-
})
107
-
),
108
-
);
109
-
110
-
await Effect.runPromise(program);
111
}
···
1
import _ from "@es-toolkit/es-toolkit/compat";
2
import chalk from "chalk";
3
+
import { Data, Effect, pipe } from "effect";
4
import type { VirtualMachine } from "../db.ts";
5
+
import { getInstanceState, updateInstanceState } from "../state.ts";
6
7
+
class VmNotFoundError extends Data.TaggedError("VmNotFoundError")<{
8
+
name: string;
9
+
}> {}
10
+
11
+
class StopCommandError extends Data.TaggedError("StopCommandError")<{
12
+
vmName: string;
13
+
exitCode: number;
14
+
}> {}
15
+
16
+
class CommandError extends Data.TaggedError("CommandError")<{
17
+
cause?: unknown;
18
+
}> {}
19
+
20
+
const findVm = (name: string) =>
21
+
pipe(
22
+
getInstanceState(name),
23
+
Effect.flatMap((vm) =>
24
+
vm ? Effect.succeed(vm) : Effect.fail(new VmNotFoundError({ name }))
25
+
),
26
+
);
27
+
28
+
const logStopping = (vm: VirtualMachine) =>
29
Effect.sync(() => {
30
console.log(
31
`Stopping virtual machine ${chalk.greenBright(vm.name)} (ID: ${
···
34
);
35
});
36
37
+
const killProcess = (vm: VirtualMachine) =>
38
+
Effect.tryPromise({
39
try: async () => {
40
+
const cmd = new Deno.Command(vm.bridge ? "sudo" : "kill", {
41
+
args: [
42
+
..._.compact([vm.bridge && "kill"]),
43
+
"-TERM",
44
+
vm.pid.toString(),
45
+
],
46
stdin: "inherit",
47
stdout: "inherit",
48
stderr: "inherit",
49
});
50
51
+
const status = await cmd.spawn().status;
52
+
return { vm, status };
53
},
54
+
catch: (error) => new CommandError({ cause: error }),
55
+
}).pipe(
56
+
Effect.flatMap(({ vm, status }) =>
57
+
status.success ? Effect.succeed(vm) : Effect.fail(
58
+
new StopCommandError({
59
+
vmName: vm.name,
60
+
exitCode: status.code || 1,
61
+
}),
62
+
)
63
+
),
64
+
);
65
66
+
const updateToStopped = (vm: VirtualMachine) =>
67
+
pipe(
68
+
updateInstanceState(vm.name, "STOPPED"),
69
+
Effect.map(() => vm),
70
+
);
71
72
+
const logSuccess = (vm: VirtualMachine) =>
73
Effect.sync(() => {
74
console.log(`Virtual machine ${chalk.greenBright(vm.name)} stopped.`);
75
});
76
77
+
const handleError = (
78
+
error: VmNotFoundError | StopCommandError | CommandError | Error,
79
+
) =>
80
+
Effect.sync(() => {
81
+
if (error instanceof VmNotFoundError) {
82
+
console.error(
83
+
`Virtual machine with name or ID ${
84
+
chalk.greenBright(error.name)
85
+
} not found.`,
86
+
);
87
+
Deno.exit(1);
88
+
} else if (error instanceof StopCommandError) {
89
+
console.error(
90
+
`Failed to stop virtual machine ${chalk.greenBright(error.vmName)}.`,
91
+
);
92
+
Deno.exit(error.exitCode);
93
+
} else {
94
+
console.error(`An error occurred: ${error}`);
95
+
Deno.exit(1);
96
+
}
97
+
});
98
99
+
const stopEffect = (name: string) =>
100
pipe(
101
+
findVm(name),
102
+
Effect.tap(logStopping),
103
+
Effect.flatMap(killProcess),
104
+
Effect.flatMap(updateToStopped),
105
+
Effect.tap(logSuccess),
106
+
Effect.catchAll(handleError),
107
);
108
109
export default async function (name: string) {
110
+
await Effect.runPromise(stopEffect(name));
111
}