private static void writeJson(HttpServletRequest request, Writer writer, Object output)
throws IOException {
Map<String, Object> json = new CompactMap<String, Object>();
if (output instanceof Throwable) {
Throwable error = (Throwable) output;
json.put("status", "error");
json.put("errorClass", error.getClass().getName());
json.put("errorMessage", error.getMessage());
} else {
if (!"html".equals(request.getParameter("_result"))) {
output =
HtmlMicrodata.Static.parseString(
new URL(JspUtils.getAbsoluteUrl(request, "")), (String) output);
}
json.put("status", "ok");
json.put("result", output);
}
writer.write(ObjectUtils.toJson(json));
}
@Override
protected void doRequest(
HttpServletRequest request, HttpServletResponse response, FilterChain chain)
throws IOException, ServletException {
String format = request.getParameter("_format");
if (ObjectUtils.isBlank(format)) {
chain.doFilter(request, response);
return;
}
Writer writer = response.getWriter();
if ("js".equals(format)) {
response.setContentType("text/javascript");
writer.write("(function(window, undefined) {");
writer.write("var d = window.document,");
writer.write("ss = d.getElementsByTagName('SCRIPT'),");
writer.write("s = ss[ss.length - 1],");
writer.write("f = d.createElement('IFRAME'),");
writer.write("h;");
writer.write("f.scrolling = 'no';");
writer.write("f.style.border = 'none';");
writer.write("f.style.width = '100%';");
writer.write("f.src = '");
writer.write(
StringUtils.escapeJavaScript(JspUtils.getAbsoluteUrl(request, "", "_format", "_frame")));
writer.write("';");
writer.write("s.parentNode.insertBefore(f, s);");
writer.write("s.parentNode.removeChild(s);");
writer.write("window.addEventListener('message', function(event) {");
writer.write("var nh = parseInt(event.data, 10);");
writer.write("if (h !== nh) {");
writer.write("f.style.height = nh + 'px';");
writer.write("h = nh;");
writer.write("}");
writer.write("}, false);");
writer.write("})(window);");
return;
} else if ("_frame".equals(format)) {
@SuppressWarnings("resource")
HtmlWriter html = new HtmlWriter(writer);
response.setContentType("text/html");
html.writeTag("!doctype html");
html.writeStart("html");
html.writeStart("head");
html.writeEnd();
html.writeStart(
"body",
"style",
html.cssString(
"margin", 0,
"padding", 0));
html.writeStart(
"iframe",
"scrolling",
"no",
"src",
JspUtils.getAbsoluteUrl(request, "", "_format", null),
"style",
html.cssString(
"border", "none",
"width", "100%"));
html.writeEnd();
html.writeStart("script", "type", "text/javascript");
html.writeRaw("(function(window, undefined) {");
html.writeRaw("setInterval(function() {");
html.writeRaw(
"var f = document.getElementsByTagName('iframe')[0], h = f.contentDocument.body.scrollHeight;");
html.writeRaw("f.height = h + 'px';");
html.writeRaw("window.parent.postMessage('' + h, '*');");
html.writeRaw("}, 500);");
html.writeRaw("})(window);");
html.writeEnd();
html.writeEnd();
html.writeEnd();
return;
}
CapturingResponse capturing = new CapturingResponse(response);
Object output;
try {
chain.doFilter(request, capturing);
output = capturing.getOutput();
} catch (RuntimeException error) {
output = error;
}
if ("json".equals(format)) {
response.setContentType("application/json");
writeJson(request, writer, output);
} else if ("jsonp".equals(format)) {
String callback = request.getParameter("_callback");
// Legacy parameter support.
if (ObjectUtils.isBlank(callback)) {
callback = request.getParameter("callback");
}
Preconditions.checkArgument(!ObjectUtils.isBlank(callback));
response.setContentType("application/javascript");
writer.write(callback);
writer.write("(");
writeJson(request, writer, output);
writer.write(");");
} else if ("oembed".equals(format)) {
response.setContentType("application/json+oembed");
Map<String, Object> json = new CompactMap<String, Object>();
StringWriter string = new StringWriter();
@SuppressWarnings("resource")
HtmlWriter html = new HtmlWriter(string);
html.writeStart(
"script",
"type",
"text/javascript",
"src",
JspUtils.getAbsoluteUrl(request, "", "_format", "js"));
html.writeEnd();
json.put("version", "1.0");
json.put("type", "rich");
json.put("html", string.toString());
writer.write(ObjectUtils.toJson(json));
} else {
throw new IllegalArgumentException(
String.format("[%s] isn't a valid API response format!", format));
}
}