cache bbox,translate to english,support views

bbox.js

 // based on https://raw.githubusercontent.com/tobinbradley/dirt-simple-postgis-http-api/master/routes/bbox.js
 
 const sqlTableName = require('./utils/sqltablename.js');
+const DirCache = require('./utils/dircache.js')
+const cache = new DirCache('./cache');
 
 
 const sql = (params, query) => {
@@ -18,6 +20,30 @@ select allrows, geomrows, bboxll,srid,bboxsrid from bboxll,srid,bboxsrid
       `
 }
 
+let cacheMiddleware = async(req, res, next) => {
+  const cacheDir = `${req.params.table}/bbox`
+  const key = ((req.query.geom_column?req.query.geom_column:'geom') 
+    + (req.query.columns?'_'+req.query.columns:'')
+    + (req.query.filter?'_'+req.query.filter:''))
+    .replace(/[\W]+/g, '_');
+
+  const bbox = await cache.getCachedFile(cacheDir, key);
+  if (bbox) {
+    console.log(`bbox cache hit for ${cacheDir}?${key}`);
+    res.header('Content-Type', 'application/json').send(bbox);
+    return;
+  } else {
+    res.sendResponse = res.send;
+    res.send = (body) => {
+      if (res.statusCode >= 200 && res.statusCode < 300) {
+        cache.setCachedFile(cacheDir, key, body);
+      }
+      res.sendResponse(body);
+    }
+    next();
+  }
+}
+
 module.exports = function(app, pool) {
 /**
  * @swagger
@@ -38,11 +64,6 @@ module.exports = function(app, pool) {
  *         description: name of geometry column (default 'geom')
  *         in: query
  *         required: false
- *       - name: strid
- *         description: 'The SRID for the returned centroid. The default is <em>4326</em> WGS84 Lat/Lng.'
- *         in: query
- *         required: false
- *         type: integer
  *       - name: filter
  *         type: string
  *         description: 'Optional filter parameters for a SQL WHERE statement.'
@@ -50,13 +71,47 @@ module.exports = function(app, pool) {
  *         required: false
  *     responses:
  *       200:
- *         description: vector tile
- *       204:
- *         description: no data (empty tile)
+ *         description: boundingboxes and row counters
+ *         content:
+ *            application/json
+ *         schema:
+ *            type: object
+ *            properties:
+ *               allrows:
+ *                 type: integer
+ *                 description: number of rows in table
+ *               geomrows:
+ *                  type: integer
+ *                  description: number of non-null geometries in table
+ *               bboxll:
+ *                  description: boundingbox of geometries defined in latitude and longitude
+ *                  type: array
+ *                  minItems: 2
+ *                  maxItems: 2
+ *                  items:
+ *                     type: array
+ *                     minItems: 2
+ *                     maxItems: 2
+ *                     items: 
+ *                       type: number
+ *               srid:
+ *                   type: integer
+ *                   description: id of spatial reference system (EPSG code) used by geometries
+ *               bboxsrid:
+ *                  description: boundingbox of geometries defined using geometry srid 
+ *                  type: array
+ *                  minItems: 2
+ *                  maxItems: 2
+ *                  items:
+ *                     type: array
+ *                     minItems: 2
+ *                     maxItems: 2
+ *                     items: 
+ *                       type: number
  *       422:
  *         description: invalid datasource or columnname
  */
-  app.get('/api/bbox/:table', async (req, res)=>{
+  app.get('/api/bbox/:table', cacheMiddleware, async (req, res)=>{
       if (!req.query.geom_column) {
         req.query.geom_column = 'geom'; //default
       }

public/attrinfo.html

@@ -252,10 +252,10 @@
             if (response.ok) {
                 response.json().then(json=> {
                     const div = document.querySelector('#attrinfo');
-                    div.innerHTML = `<b>aantal</b>:${json[0].count}<br>
-                    <b>verschillend</b>:${json[0].distinct}<br>
-                    <b>min</b>:${json[0].min}<br>
-                    <b>max</b>:${json[0].max}<br>`;
+                    div.innerHTML = `<b>count</b>:${json[0].count}<br>
+                    <b>nr of unique values</b>:${json[0].distinct}<br>
+                    <b>minimum</b>:${json[0].min}<br>
+                    <b>maximum</b>:${json[0].max}<br>`;
                 })
             }
         })
@@ -358,7 +358,7 @@ linearTicks.min: ${linearTicks.min}, linearTicks.max: ${linearTicks.max}, linear
                             data: {
                                 labels: histLabels,
                                 datasets: [{
-                                    label: `aantal ${tableName}`,
+                                    label: `count of ${tableName}`,
                                     data: values,
                                     backgroundColor: "blue",
                                     borderColor: "white",
@@ -426,7 +426,7 @@ linearTicks.min: ${linearTicks.min}, linearTicks.max: ${linearTicks.max}, linear
     </script>
 </head>
 <body onload="init()">
-    <h1>Attribuut-informatie</h1>
+    <h1>Attribuut-information</h1>
     <h2 id="tablename"></h2>
     <h2 id="columnname"></h2>
     <div id="attrinfo"></div>

public/info.html

@@ -67,7 +67,7 @@
         table.innerHTML = '<tr><th>schema</th><th>name</th><th>geom_column</th><th>srid</th><th>geom_type</th><th>dim</th><th>count</th></tr>' +
             layerInfo.map(item=>`<tr>
                 <td>${item.f_table_schema}</td>
-                <td>${Number(item.estimated_rows)?`<a href="tableinfo.html?table=${item.f_table_schema}.${item.f_table_name}&geom_column=${item.f_geometry_column}&srid=${item.srid}&geomtype=${item.type}&dimensions=${item.coord_dimension}&estimated_rows=${item.estimated_rows}">${item.f_table_name}</a>`:`${item.f_table_name}`}</td>
+                <td><a href="tableinfo.html?table=${item.f_table_schema}.${item.f_table_name}&geom_column=${item.f_geometry_column}&srid=${item.srid}&geomtype=${item.type}&dimensions=${item.coord_dimension}&estimated_rows=${item.estimated_rows}">${item.f_table_name}</a></td>
                 <td>${item.f_geometry_column}</td>
                 <td>${item.srid}</td>
                 <td>${item.type}</td>