Function ginMiddlewareChainEdges

src/resolution/callback-synthesizer.ts:1524–1582

(queries: QueryBuilder, ctx: ResolutionContext)

}

function ginMiddlewareChainEdges(queries: QueryBuilder, ctx: ResolutionContext): Edge[] {
  // 1. Find the chain dispatcher(s): a Go method that invokes a `handlers` slice by index.
  const dispatchers: Node[] = [];
  for (const n of queries.iterateNodesByKind('method')) {
    if (n.language !== 'go') continue;
    const content = ctx.readFile(n.filePath);
    const src = content && sliceLines(content, n.startLine, n.endLine);
    if (src && GIN_DISPATCH_RE.test(src)) dispatchers.push(n);
  }
  if (dispatchers.length === 0) return [];                              // not a gin repo — bail

  // 2. Collect handler identifiers registered via gin registration calls
  //    (.Use / .GET / … / .Handle). String args (paths/methods) and inline
  //    closures are dropped by goHandlerIdent; the rest are HandlerFuncs.
  const registered = new Map<string, string>();                         // name → registeredAt (file:line)
  for (const file of ctx.getAllFiles()) {
    if (!file.endsWith('.go')) continue;
    const content = ctx.readFile(file);
    if (!content || (!content.includes('.Use(') && !/\.(?:GET|POST|PUT|PATCH|DELETE|OPTIONS|HEAD|Any|Handle)\(/.test(content))) continue;
    const safe = stripCommentsForRegex(content, 'go');
    GIN_REG_RE.lastIndex = 0;
    let m: RegExpExecArray | null;
    while ((m = GIN_REG_RE.exec(safe))) {
      const parenIdx = m.index + m[0].length - 1;
      const argStr = goBalancedArgs(safe, parenIdx);
      if (!argStr) continue;
      const line = safe.slice(0, m.index).split('\n').length;
      for (const arg of goSplitArgs(argStr)) {
        const name = goHandlerIdent(arg);
        if (name && !registered.has(name)) registered.set(name, `${file}:${line}`);
      }
    }
  }
  if (registered.size === 0) return [];

  // 3. Link each dispatcher → each registered handler node (dedup, capped).
  const edges: Edge[] = [];
  const seen = new Set<string>();
  for (const disp of dispatchers) {
    let added = 0;
    for (const [name, registeredAt] of registered) {
      if (added >= MAX_CALLBACKS_PER_CHANNEL) break;
      const handler = ctx.getNodesByName(name).find(
        (n) => (n.kind === 'function' || n.kind === 'method') && n.language === 'go'
      );
      if (!handler || handler.id === disp.id) continue;
      const key = `${disp.id}>${handler.id}`;
      if (seen.has(key)) continue;
      seen.add(key);
      edges.push({
        source: disp.id, target: handler.id, kind: 'calls', line: disp.startLine,
        provenance: 'heuristic',
        metadata: { synthesizedBy: 'gin-middleware-chain', via: name, registeredAt },
      });
      added++;
    }
  }
  return edges;