tailtriage-analyzer 0.2.0

Heuristic triage analyzer and report rendering for tailtriage runs
Documentation 
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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141

use super::{Confidence, EvidenceQualityLevel, Report, TemporalSegment};

fn fmt_opt_u64(value: Option<u64>) -> String {
    match value {
        Some(value) => value.to_string(),
        None => "n/a".to_string(),
    }
}

fn fmt_percent_permille(value: Option<u64>) -> String {
    match value {
        Some(value) => format!("{}.{:01}%", value / 10, value % 10),
        None => "n/a".to_string(),
    }
}

fn fmt_confidence(confidence: Confidence) -> &'static str {
    match confidence {
        Confidence::Low => "low",
        Confidence::Medium => "medium",
        Confidence::High => "high",
    }
}

/// Renders a compact text triage summary from a [`Report`].
///
/// The rendered output is guidance for follow-up checks, not proof of root cause.
#[must_use]
pub fn render_text(report: &Report) -> String {
    let mut lines = vec![
        "tailtriage diagnosis".to_string(),
        format!("Requests analyzed: {}", report.request_count),
        format!(
            "Latency (us): p50 {}, p95 {}, p99 {}",
            fmt_opt_u64(report.p50_latency_us),
            fmt_opt_u64(report.p95_latency_us),
            fmt_opt_u64(report.p99_latency_us),
        ),
        format!(
            "Request time at p95: queue {}, non-queue service {}",
            fmt_percent_permille(report.p95_queue_share_permille),
            fmt_percent_permille(report.p95_service_share_permille),
        ),
    ];

    match &report.inflight_trend {
        Some(trend) => {
            lines.push(format!(
                "Inflight trend: gauge '{}', samples {}, peak {}, p95 {}, net growth {:+}",
                trend.gauge,
                trend.sample_count,
                trend.peak_count,
                trend.p95_count,
                trend.growth_delta,
            ));
        }
        None => lines.push("Inflight trend: none".to_string()),
    }

    lines.push(format!(
        "Primary suspect: {} ({} confidence, score {})",
        report.primary_suspect.kind.as_str(),
        fmt_confidence(report.primary_suspect.confidence),
        report.primary_suspect.score,
    ));
    lines.push(format!(
        "Evidence quality: {}{}",
        match report.evidence_quality.quality {
            EvidenceQualityLevel::Strong => "strong",
            EvidenceQualityLevel::Partial => "partial",
            EvidenceQualityLevel::Weak => "weak",
        },
        report
            .evidence_quality
            .limitations
            .first()
            .map_or_else(String::new, |l| format!(" ({l})"))
    ));

    if !report.warnings.is_empty() {
        lines.push("Warnings:".to_string());
        for warning in &report.warnings {
            lines.push(format!("- {warning}"));
        }
    }
    if !report.primary_suspect.evidence.is_empty() {
        lines.push("Evidence:".to_string());
        for evidence in &report.primary_suspect.evidence {
            lines.push(format!("- {evidence}"));
        }
    }
    if !report.primary_suspect.next_checks.is_empty() {
        lines.push("Next checks:".to_string());
        for next_check in &report.primary_suspect.next_checks {
            lines.push(format!("- {next_check}"));
        }
    }
    if !report.secondary_suspects.is_empty() {
        lines.push("Secondary suspects:".to_string());
        for suspect in &report.secondary_suspects {
            lines.push(format!(
                "- {} ({} confidence, score {})",
                suspect.kind.as_str(),
                fmt_confidence(suspect.confidence),
                suspect.score
            ));
        }
    }
    if !report.route_breakdowns.is_empty() {
        lines.push("Route breakdowns:".to_string());
        for route in &report.route_breakdowns {
            lines.push(format!(
                "- {}: requests {}, p95 {}us, suspect {} ({} confidence)",
                route.route,
                route.request_count,
                fmt_opt_u64(route.p95_latency_us),
                route.primary_suspect.kind.as_str(),
                fmt_confidence(route.primary_suspect.confidence)
            ));
        }
    }
    append_temporal_segment_text(&mut lines, &report.temporal_segments);
    lines.join("\n")
}

fn append_temporal_segment_text(lines: &mut Vec<String>, segments: &[TemporalSegment]) {
    if segments.is_empty() {
        return;
    }
    lines.push("Temporal segments:".to_string());
    for seg in segments {
        lines.push(format!(
            "- {}: requests {}, p95 {}us, suspect {} ({} confidence)",
            seg.name,
            seg.request_count,
            fmt_opt_u64(seg.p95_latency_us),
            seg.primary_suspect.kind.as_str(),
            fmt_confidence(seg.primary_suspect.confidence)
        ));
    }
}