Get all the http servers working with OM.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>

Author: brian-brazil

simpleclient_common/src/main/java/io/prometheus/client/exporter/common/TextFormat.java

@@ -218,6 +218,7 @@ public static void writeOpenMetrics100(Writer writer, Enumeration<Collector.Metr
         writer.write('\n');
       }
     }
+    writer.write("# EOF\n");
   }
 
   private static String omTypeString(Collector.Type t) {

simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/TestHTTPServer.java

@@ -65,6 +65,17 @@ String requestWithCompression(String context, String suffix) throws IOException
     return s.hasNext() ? s.next() : "";
   }
 
+  String requestWithAccept(String accept) throws IOException {
+    String url = "http://localhost:" + s.server.getAddress().getPort();
+    URLConnection connection = new URL(url).openConnection();
+    connection.setDoOutput(true);
+    connection.setDoInput(true);
+    connection.setRequestProperty("Accept", accept);
+    Scanner s = new Scanner(connection.getInputStream(), "UTF-8").useDelimiter("\\A");
+    return s.hasNext() ? s.next() : "";
+  }
+
+  @Test
   @Test(expected = IllegalArgumentException.class)
   public void testRefuseUsingUnbound() throws IOException {
     CollectorRegistry registry = new CollectorRegistry();
@@ -120,6 +131,12 @@ public void testGzipCompression() throws IOException {
     assertThat(response).contains("c 0.0");
   }
 
+  @Test
+  public void testOpenMetrics() throws IOException {
+    String response = requestWithAccept("application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1");
+    assertThat(response).contains("# EOF");
+  }
+
   @Test
   public void testHealth() throws IOException {
     String response = request("/-/healthy", "");

simpleclient_servlet/src/main/java/io/prometheus/client/exporter/MetricsServlet.java

@@ -42,11 +42,12 @@ public MetricsServlet(CollectorRegistry registry) {
   protected void doGet(final HttpServletRequest req, final HttpServletResponse resp)
           throws ServletException, IOException {
     resp.setStatus(HttpServletResponse.SC_OK);
-    resp.setContentType(TextFormat.CONTENT_TYPE_004);
+    String contentType = TextFormat.chooseContentType(req.getHeader("Accept"));
+    resp.setContentType(contentType);
 
     Writer writer = new BufferedWriter(resp.getWriter());
     try {
-      TextFormat.write004(writer, registry.filteredMetricFamilySamples(parse(req)));
+      TextFormat.writeFormat(contentType, writer, registry.filteredMetricFamilySamples(parse(req)));
       writer.flush();
     } finally {
       writer.close();

simpleclient_servlet/src/test/java/io/prometheus/client/exporter/MetricsServletTest.java

@@ -74,4 +74,23 @@ public void testWriterIsClosedOnException() throws IOException, ServletException
 
     verify(writer).close();
   }
+
+  @Test
+  public void testOpenMetricsNegotiated() throws IOException, ServletException {
+    CollectorRegistry registry = new CollectorRegistry();
+    Gauge.build("a", "a help").register(registry);
+
+    HttpServletRequest req = mock(HttpServletRequest.class);
+    when(req.getHeader("Accept")).thenReturn("application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1");
+    HttpServletResponse resp = mock(HttpServletResponse.class);
+    StringWriter stringWriter = new StringWriter();
+    PrintWriter writer = new PrintWriter(stringWriter);
+    when(resp.getWriter()).thenReturn(writer);
+
+    new MetricsServlet(registry).doGet(req, resp);
+
+    assertThat(stringWriter.toString()).contains("a 0.0");
+    assertThat(stringWriter.toString()).contains("# EOF");
+  }
+
 }

simpleclient_spring_boot/src/main/java/io/prometheus/client/spring/boot/PrometheusEndpoint.java

@@ -23,13 +23,13 @@ class PrometheusEndpoint extends AbstractEndpoint<String> {
 
   @Override
   public String invoke() {
-    return writeRegistry(Collections.<String>emptySet());
+    return writeRegistry(Collections.<String>emptySet(), "");
   }
 
-  public String writeRegistry(Set<String> metricsToInclude) {
+  public String writeRegistry(Set<String> metricsToInclude, String contentType) {
     try {
       Writer writer = new StringWriter();
-      TextFormat.write004(writer, collectorRegistry.filteredMetricFamilySamples(metricsToInclude));
+      TextFormat.writeFormat(contentType, writer, collectorRegistry.filteredMetricFamilySamples(metricsToInclude));
       return writer.toString();
     } catch (IOException e) {
       // This actually never happens since StringWriter::write() doesn't throw any IOException

simpleclient_spring_boot/src/main/java/io/prometheus/client/spring/boot/PrometheusMvcEndpoint.java

@@ -4,6 +4,7 @@
 import org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.RequestHeader;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
@@ -29,16 +30,18 @@ public PrometheusMvcEndpoint(PrometheusEndpoint delegate) {
   )
   @ResponseBody
   public ResponseEntity value(
-          @RequestParam(value = "name[]", required = false, defaultValue = "") Set<String> name) {
+          @RequestParam(value = "name[]", required = false, defaultValue = "") Set<String> name,
+          @RequestHeader(value = "Accept", required = false, defaultValue = "") String accept) {
     if (!getDelegate().isEnabled()) {
       // Shouldn't happen - MVC endpoint shouldn't be registered when delegate's
       // disabled
       return getDisabledResponse();
     }
 
-    String result = delgate.writeRegistry(name);
+    String contentType = TextFormat.chooseContentType(accept);
+    String result = delgate.writeRegistry(name, contentType);
     return ResponseEntity.ok()
-            .header(CONTENT_TYPE, TextFormat.CONTENT_TYPE_004)
+            .header(CONTENT_TYPE, contentType)
             .body(result);
   }
 }

simpleclient_spring_boot/src/test/java/io/prometheus/client/spring/boot/PrometheusMvcEndpointTest.java

@@ -17,6 +17,7 @@
 import org.springframework.test.context.junit4.SpringRunner;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 import static org.springframework.boot.test.context.SpringBootTest.WebEnvironment.RANDOM_PORT;
 
 @RunWith(SpringRunner.class)
@@ -50,6 +51,19 @@ public void testAcceptPlainText() throws Exception {
         assertEquals(HttpStatus.OK, metricsResponse.getStatusCode());
     }
 
+    @Test
+    public void testAcceptOpenMetrics() throws Exception {
+
+        HttpHeaders headers = new HttpHeaders();
+        headers.set("Accept", "application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1");
+
+        ResponseEntity<String> metricsResponse = template.exchange(getBaseUrl() + "/prometheus", HttpMethod.GET, new HttpEntity(headers), String.class);
+
+        assertEquals(HttpStatus.OK, metricsResponse.getStatusCode());
+        assertEquals(StringUtils.deleteWhitespace(TextFormat.CONTENT_TYPE_OPENMETRICS_100), metricsResponse.getHeaders().getContentType().toString().toLowerCase());
+        assertTrue(metricsResponse.getBody().contains("# EOF"));
+    }
+
     @Test
     public void testNameParamIsNotNull() {
         ResponseEntity metricsResponse = template.exchange(getBaseUrl() + "/prometheus?name[]=foo_bar", HttpMethod.GET, getEntity(), String.class);
@@ -68,4 +82,4 @@ public HttpEntity getEntity() {
     private String getBaseUrl() {
         return "http://localhost:" + localServerPort;
     }
-}
+}

simpleclient_vertx/src/main/java/io/prometheus/client/vertx/MetricsHandler.java

@@ -73,10 +73,12 @@ public MetricsHandler(CollectorRegistry registry) {
   public void handle(RoutingContext ctx) {
     try {
       final BufferWriter writer = new BufferWriter();
-      TextFormat.write004(writer, registry.filteredMetricFamilySamples(parse(ctx.request())));
+      String contentType = TextFormat.chooseContentType(ctx.request().headers().get("Accept"));
+
+      TextFormat.writeFormat(contentType, writer, registry.filteredMetricFamilySamples(parse(ctx.request())));
       ctx.response()
               .setStatusCode(200)
-              .putHeader("Content-Type", TextFormat.CONTENT_TYPE_004)
+              .putHeader("Content-Type", contentType)
               .end(writer.getBuffer());
     } catch (IOException e) {
       ctx.fail(e);