Merge ticket/018-boolean-param-kind and ticket/019-docs-isError-use-case

webapp/src/components/Docs.tsx

@@ -178,6 +178,14 @@ const SECTIONS: DocSection[] = [
           a metric (see <em>Filtering</em> above — bare params aren't queryable by name on their own, only metric
           labels/values are).
         </p>
+        <p>
+          Given the same kind of lines, declaring a param named <Code>IsError</Code> with regex{' '}
+          <Code>{String.raw`(?i)error`}</Code> and type <Code>boolean</Code> — no capture group needed — shows{' '}
+          <Code>IsError</Code> as <Code>true</Code> or <Code>false</Code> on every line in the log table, based on
+          whether the regex matches that line's text case-insensitively. Unlike <Code>string</Code>/<Code>number</Code>
+          /<Code>timestamp</Code>/<Code>duration</Code> params, a <Code>boolean</Code> param is never omitted for a
+          non-matching line.
+        </p>
       </div>
     ),
   },

webapp/src/components/Params.tsx

@@ -21,12 +21,15 @@ export function Params({ params, onDeclared }: { params: ParamDeclaration[]; onD
   const [submitting, setSubmitting] = useState(false)
   const [collapsed, setCollapsed] = useSectionCollapsed('params')
 
+  const isBoolean = kind === 'boolean'
+
   async function handleSubmit(e: React.FormEvent) {
     e.preventDefault()
     setSubmitError(null)
     setSubmitting(true)
     try {
-      await declareParam({ name, message_match_regex: regex, capture_group: captureGroup, kind })
+      // A boolean-kind param never uses a capture group — its value is just whether the regex matched.
+      await declareParam({ name, message_match_regex: regex, capture_group: isBoolean ? '' : captureGroup, kind })
       setName('')
       setRegex('')
       setCaptureGroup('')
@@ -82,13 +85,16 @@ export function Params({ params, onDeclared }: { params: ParamDeclaration[]; onD
           </div>
           <div className="flex items-end gap-1">
             <div className="min-w-0 flex-1">
-              <label className="mb-1 block text-xs text-text-subtle">Capture group</label>
+              <label className="mb-1 block text-xs text-text-subtle">
+                Capture group{isBoolean && ' (unused for boolean)'}
+              </label>
               <input
-                className="w-full min-w-0 rounded border border-border-soft bg-surface-1 px-1.5 py-1 text-xs text-text placeholder:text-text-subtle focus:border-border-strong focus:outline-none"
+                className="w-full min-w-0 rounded border border-border-soft bg-surface-1 px-1.5 py-1 text-xs text-text placeholder:text-text-subtle focus:border-border-strong focus:outline-none disabled:opacity-50"
                 value={captureGroup}
                 onChange={(e) => setCaptureGroup(e.target.value)}
                 placeholder="path"
-                required
+                required={!isBoolean}
+                disabled={isBoolean}
               />
             </div>
             <select
@@ -100,6 +106,7 @@ export function Params({ params, onDeclared }: { params: ParamDeclaration[]; onD
               <option value="number">number</option>
               <option value="timestamp">timestamp</option>
               <option value="duration">duration</option>
+              <option value="boolean">boolean</option>
             </select>
           </div>
           {submitError && <div className="rounded border border-danger-border bg-danger-bg/50 px-2 py-1 text-xs text-danger-text">{submitError}</div>}
@@ -122,7 +129,7 @@ export function Params({ params, onDeclared }: { params: ParamDeclaration[]; onD
                 className="rounded border border-border-soft px-2 py-1 text-xs text-text-secondary"
                 title={p.message_match_regex}
               >
-                {p.name} ({p.kind}, group {p.capture_group})
+                {p.name} ({p.kind}{p.kind === 'boolean' ? '' : `, group ${p.capture_group}`})
               </span>
             ))}
           </div>