cb99f0b11bdeee5dfa76064d38b6410da0f4a709
max
  Thu Sep 10 00:55:21 2026 -0700
Centralize CGI Content-Type printing in one cgiPrintContentType() helper

Around 90 places across the tree hand-rolled the CGI response header, each
with its own spelling: "Content-Type:" or "Content-type:", \n or \r\n, and
the terminating blank line written as part of the same string, as a separate
puts("\n") (which emits two newlines, so a stray blank line led the body) or
as printf("\r\n\r\n") (two blank lines).  A handful forgot the terminator
entirely and relied on a following header to supply it.

cgiPrintContentType() in lib/cheapcgi.c now writes the Content-Type line and
the blank line that ends the header.  Header lines are not ordered, so the
callers that also send Status, Set-Cookie, Content-Disposition, Content-Length
or X-Sendfile write those first and call this last to close the header; that
keeps it to a single helper rather than a print-the-line / end-the-header pair
that a caller can half-use.  cart.c's existing httpHeaders list already worked
this way.

Only the CGI response path is touched.  The dyStringPrintf("Content-type: ...")
calls that build outgoing HTTP *requests* (genomeSpace, oauthLogin, eapMetaSync,
edwWebAuthLogin, ga4ghToBed) are unrelated and left alone.

Also fills out the apiKey error message in botDelay.c to say where to create a
key and that keys are server-specific.

No behavior change on the wire beyond dropping those stray blank lines and
adding the missing newline after Retry-After.

diff --git src/hg/hgGateway/hgGateway.c src/hg/hgGateway/hgGateway.c
index f4af0d2392f..3331582b0fc 100644
--- src/hg/hgGateway/hgGateway.c
+++ src/hg/hgGateway/hgGateway.c
@@ -1203,31 +1203,31 @@
 eraseTrailingSpaces(term);
 touppers(term);
 if (isEmpty(term))
     errAbort("Missing required CGI parameter %s", SEARCH_TERM);
 popWarnHandler();
 popAbortHandler();
 return term;
 }
 
 static void lookupTerm()
 /* Look for matches to term in hgcentral and print as JSON for autocomplete if found. */
 {
 char *term = getSearchTermUpperCase();
 
 // Write JSON response with list of matches
-puts("Content-Type:text/javascript\n");
+cgiPrintContentType("text/javascript");
 
 // Before accessing hubs, intialize udc cache location from hg.conf:
 setUdcCacheDir();
 struct dbDb *dbDbList = hDbDbList();
 struct dbDbMatch *matchList = searchDbDb(dbDbList, term);
 struct gHubMatch *gHubMatchList = searchGenark(dbDbList, &matchList, term);
 struct aHubMatch *aHubMatchList = searchPublicHubs(dbDbList, term);
 struct jsonWrite *jw = jsonWriteNew();
 jsonWriteListStart(jw, NULL);
 // Write out JSON for dbDb matches, if any; add category if we found assembly hub matches too.
 char *category = aHubMatchList ? "UCSC Genome Browser assemblies - annotation tracks curated by UCSC" : NULL;
 struct dbDbMatch *match;
 for (match = matchList;  match != NULL;  match = match->next)
     writeDbDbMatch(jw, match, term, category);