pub fn make_timeout_completion<F>(
timeout: Duration,
f: F,
) -> impl Fn(&Context, &str) -> Result<CompletionResult>Expand description
Creates a timeout-wrapped completion function
This is a convenience function that creates a new completion function with built-in timeout handling.
§Arguments
timeout- Maximum duration to wait for completionf- The original completion function
§Returns
A new completion function that enforces the timeout
Examples found in repository?
examples/timeout_completion_demo.rs (lines 71-99)
30fn main() {
31 let app = CommandBuilder::new("cloud-cli")
32 .short("Cloud CLI with timeout-protected completions")
33 .flag(
34 Flag::new("region")
35 .short('r')
36 .usage("Cloud region")
37 .value_type(FlagType::String)
38 .default(flag_rs::FlagValue::String("us-east-1".to_string())),
39 )
40 .subcommand(
41 CommandBuilder::new("instances")
42 .short("Manage cloud instances")
43 .subcommand(
44 CommandBuilder::new("list")
45 .short("List instances (fast completion)")
46 .arg_completion(|_ctx, prefix| {
47 // Fast completion - no timeout needed
48 let instances = vec![
49 "web-server-001",
50 "web-server-002",
51 "db-primary",
52 "db-replica",
53 "cache-node-1",
54 "cache-node-2",
55 ];
56
57 Ok(CompletionResult::new().extend(
58 instances
59 .into_iter()
60 .filter(|i| i.starts_with(prefix))
61 .map(String::from),
62 ))
63 })
64 .build(),
65 )
66 .subcommand(
67 CommandBuilder::new("describe")
68 .short("Describe instance (slow completion with timeout)")
69 .arg_completion({
70 // Wrap slow completion with timeout
71 make_timeout_completion(
72 Duration::from_millis(500), // 500ms timeout
73 |ctx, prefix| {
74 eprintln!("Fetching instance details from API...");
75
76 // Simulate slow API call (1 second)
77 let instances = slow_completion(prefix, 1000);
78
79 let mut result = CompletionResult::new();
80 for instance in instances {
81 result = result.add_with_description(
82 instance.clone(),
83 format!(
84 "Instance in region {}",
85 ctx.flag("region")
86 .unwrap_or(&"us-east-1".to_string())
87 ),
88 );
89 }
90
91 if prefix.is_empty() {
92 result = result.add_help_text(
93 "Fetching live instance data from cloud API...",
94 );
95 }
96
97 Ok(result)
98 },
99 )
100 })
101 .build(),
102 )
103 .subcommand(
104 CommandBuilder::new("create")
105 .short("Create instance (very slow completion)")
106 .arg_completion({
107 // Use default timeout (2 seconds)
108 make_timeout_completion(DEFAULT_COMPLETION_TIMEOUT, |_ctx, prefix| {
109 eprintln!("Checking available instance types...");
110
111 // Simulate very slow operation (3 seconds)
112 let types = slow_completion(prefix, 3000);
113
114 Ok(CompletionResult::new()
115 .extend(types)
116 .add_help_text("Available instance types"))
117 })
118 })
119 .build(),
120 )
121 .build(),
122 )
123 .build();
124
125 println!("=== Timeout Completion Demo ===\n");
126 println!("This demo shows how timeouts protect against slow completion operations.\n");
127 println!("To test timeout handling:");
128 println!("1. Set up bash completion:");
129 println!(
130 " source <({} completion bash)",
131 std::env::args().next().unwrap_or_default()
132 );
133 println!();
134 println!("2. Test different completion speeds:");
135 println!();
136 println!(" Fast (no timeout needed):");
137 println!(
138 " {} instances list <TAB>",
139 std::env::args().next().unwrap_or_default()
140 );
141 println!();
142 println!(" Slow (500ms timeout, 1s operation - will timeout):");
143 println!(
144 " {} instances describe <TAB>",
145 std::env::args().next().unwrap_or_default()
146 );
147 println!();
148 println!(" Very slow (2s timeout, 3s operation - will timeout):");
149 println!(
150 " {} instances create <TAB>",
151 std::env::args().next().unwrap_or_default()
152 );
153 println!();
154 println!("When a timeout occurs, you'll see:");
155 println!("- A warning message about the timeout");
156 println!("- Any partial results that were available");
157 println!("- Suggestion to use a more specific prefix");
158 println!("\n---\n");
159
160 let args: Vec<String> = std::env::args().skip(1).collect();
161 if let Err(e) = app.execute(args) {
162 eprintln!("{}", e);
163 std::process::exit(1);
164 }
165}