feat(usage): parse the TokenTracker sessions export defensively

2026-08-24 13:34:01 +02:00
parent 16952b6432
commit 106f9a374a
2 changed files with 198 additions and 0 deletions
@@ -0,0 +1,98 @@
+using System.Text.Json;
+
+namespace ClaudeDo.Worker.Usage.TokenTracker;
+
+/// <summary>
+/// Parses <c>tokentracker sessions --format json</c>. The export is not a promised API, so every
+/// field is read defensively: a missing number becomes 0, an unreadable row is skipped, and
+/// unparseable output returns null rather than throwing into the caller's face.
+/// </summary>
+public static class TokenTrackerExportParser
+{
+    /// <summary>The <c>version</c> value this parser was written against (CLI v0.88.4).</summary>
+    public const int SupportedFormatVersion = 11;
+
+    public static TokenTrackerExport? Parse(string? json, DateTime fetchedAtUtc)
+    {
+        if (string.IsNullOrWhiteSpace(json)) return null;
+
+        JsonDocument doc;
+        try { doc = JsonDocument.Parse(json); }
+        catch (JsonException) { return null; }
+
+        using (doc)
+        {
+            var root = doc.RootElement;
+            if (root.ValueKind != JsonValueKind.Object) return null;
+            if (!root.TryGetProperty("sessions", out var sessions) ||
+                sessions.ValueKind != JsonValueKind.Array) return null;
+
+            var parsed = new List<TokenTrackerSession>();
+            var version = 0;
+
+            foreach (var row in sessions.EnumerateArray())
+            {
+                if (row.ValueKind != JsonValueKind.Object) continue;
+
+                version = Math.Max(version, (int)GetLong(row, "version"));
+
+                var hash = GetString(row, "session_hash");
+                if (string.IsNullOrWhiteSpace(hash)) continue;
+
+                var source = GetString(row, "source") ?? "";
+                if (!string.Equals(source, "claude", StringComparison.OrdinalIgnoreCase)) continue;
+
+                if (!DateTimeOffset.TryParse(GetString(row, "started_at"), out var startedAt)) continue;
+
+                var tokens = row.TryGetProperty("tokens", out var t) && t.ValueKind == JsonValueKind.Object
+                    ? t
+                    : default;
+
+                parsed.Add(new TokenTrackerSession(
+                    SessionHash: hash!,
+                    Source: source,
+                    Model: GetString(row, "model") ?? "",
+                    StartedAt: startedAt,
+                    InputTokens: GetLong(tokens, "input_tokens"),
+                    OutputTokens: GetLong(tokens, "output_tokens"),
+                    CacheReadTokens: GetLong(tokens, "cached_input_tokens"),
+                    CacheCreationTokens: GetLong(tokens, "cache_creation_input_tokens"),
+                    CostUsd: GetDouble(row, "cost_usd"),
+                    Turns: (int)GetLong(row, "turns"),
+                    RetryTurns: (int)GetLong(row, "retry_turns"),
+                    Productive: GetBool(row, "productive"),
+                    OneShot: GetBool(row, "one_shot")));
+            }
+
+            return new TokenTrackerExport(version, parsed, fetchedAtUtc);
+        }
+    }
+
+    private static string? GetString(JsonElement obj, string prop) =>
+        obj.ValueKind == JsonValueKind.Object &&
+        obj.TryGetProperty(prop, out var el) &&
+        el.ValueKind == JsonValueKind.String
+            ? el.GetString()
+            : null;
+
+    private static long GetLong(JsonElement obj, string prop) =>
+        obj.ValueKind == JsonValueKind.Object &&
+        obj.TryGetProperty(prop, out var el) &&
+        el.ValueKind == JsonValueKind.Number &&
+        el.TryGetInt64(out var v)
+            ? v
+            : 0;
+
+    private static double GetDouble(JsonElement obj, string prop) =>
+        obj.ValueKind == JsonValueKind.Object &&
+        obj.TryGetProperty(prop, out var el) &&
+        el.ValueKind == JsonValueKind.Number &&
+        el.TryGetDouble(out var v)
+            ? v
+            : 0;
+
+    private static bool GetBool(JsonElement obj, string prop) =>
+        obj.ValueKind == JsonValueKind.Object &&
+        obj.TryGetProperty(prop, out var el) &&
+        el.ValueKind == JsonValueKind.True;
+}