tests: add test for 'Basic Heatmap' example

Author: striezel

export-server/tests/charts/scientific/heatmap.test.js

@@ -0,0 +1,91 @@
+const assert = require('node:assert');
+const http = require('node:http');
+const { describe, it } = require('node:test');
+
+describe('scientific charts, part 2', () => {
+  describe('heatmaps', () => {
+    it('Basic Heatmap', () => {
+      const options = {
+        port: 3000,
+        host: 'localhost',
+        method: 'POST'
+      };
+
+      const req = http.request(options);
+      // Data taken from https://plotly.com/javascript/heatmaps/#basic-heatmap example.
+      const payload = `{
+                         "data": [
+                           {
+                             "z": [ [ 1, 20, 30 ],
+                                    [ 20, 1, 60 ],
+                                    [ 30, 60, 1 ]
+                                  ],
+                             "type": "heatmap"
+                           }
+                         ],
+                         "layout": {}
+                       }`;
+      req.write(payload);
+      req.end();
+
+      req.on('response', (response) => {
+        assert.strictEqual(500, response.statusCode);
+        let body = '';
+        response.on('data', (chunk) => {
+          body += chunk;
+        });
+        response.on('end', () => {
+          // Browser-based answer is an SVG with embedded binary PNG image data
+          // (due to heatmap colouring).
+
+          // Currently, the server cannot handle that and returns HTTP status code 500.
+          // Reasons seem to be the heatmap colouring and the labels.
+          assert.ok(body == '{"success":false,"failure":"promise-rejected"}');
+        });
+      });
+    });
+
+    // TODO: Heatmap with Categorical Axis Labels - https://plotly.com/javascript/heatmaps/#heatmap-with-categorical-axis-labels
+    // TODO: Annotated Heatmap - https://plotly.com/javascript/heatmaps/#annotated-heatmap
+    // TODO: Heatmap with Unequal Block Sizes - https://plotly.com/javascript/heatmaps/#heatmap-with-unequal-block-sizes
+
+/*
+    it('request with different data', () => {
+      const options = {
+        port: 3000,
+        host: 'localhost',
+        method: 'POST'
+      };
+
+      const req = http.request(options);
+      // Data taken from https://plotly.com/javascript/... example.
+      const payload = '{ "x": ["2013-10-04 22:23:00", "2013-11-04 22:23:00", "2013-12-04 22:23:00"], "y": [1, 3, 6], "type": "scatter" }';
+      req.write(payload);
+      req.end();
+
+      req.on('response', (response) => {
+        assert.strictEqual(200, response.statusCode);
+        let body = '';
+        response.on('data', (chunk) => {
+          body += chunk;
+        });
+        response.on('end', () => {
+          assert.ok(body.startsWith('<svg'));
+          assert.ok(body.endsWith('</svg>'));
+
+          // Browser-based answer is something like
+          // <svg ..
+
+          // Current server response is visually almost the same.
+          // <svg ...
+
+          // Check partial matches, avoiding the random id bits.
+          assert.ok(body.indexOf('') >= 0);
+          assert.ok(body.indexOf('') > 0);
+          assert.ok(body.indexOf('') > 0);
+        });
+      });
+    });
+    */
+  });
+});