Adds the If-Modified-Since header parsing to api/v1/enties/:spec: cal…

…ls (nightscout#3571)
dallascyclist · May 18, 2018 · a354405 · a354405
1 parent 57beae5
commit a354405
Showing 1 changed file with 37 additions and 1 deletion.
diff --git a/lib/api/entries/index.js b/lib/api/entries/index.js
@@ -83,9 +83,11 @@ function configure (app, wares, ctx) {
         res.setHeader('Last-Modified', lastEntryDate.toUTCString());
       }
 
-      var ifModifiedSince = req.get('If-Modified-Since');
+      var ifModifiedSince = req.get('If-Modified-Since');	
       if (!ifModifiedSince) { return next(); }
 
+      console.log("CGM Entry request with If-Modified-Since: ", ifModifiedSince);
+
       if (lastEntryDate.getTime() <= new Date(ifModifiedSince).getTime()) {
         res.status(304).send({status:304, message: 'Not modified', type:'internal'});
         return;
@@ -114,6 +116,40 @@ function configure (app, wares, ctx) {
       if (res.entries_err) {
         return res.sendJSONStatus(res, consts.HTTP_INTERNAL_ERROR, 'Mongo Error', res.entries_err);
       }
+
+      // IF-Modified-Since support
+
+      function compare(a,b) {
+         var a_field = a.mills ? a.mills : a.date;
+         var b_field = b.mills ? b.mills : b.date;
+
+ 		 if (a_field < b_field)
+  		  return -1;
+    	 if (a_field > b_field)
+		    return 1;
+	    return 0;
+	  }
+
+  	res.entries.sort(compare);
+
+      var lastEntry = _.last(res.entries);
+      var lastEntryDate = null;
+
+      if (!_.isNil(lastEntry)) {
+      	if (lastEntry.mills) lastEntryDate = new Date(lastEntry.mills);
+      	if (!lastEntry.mills && lastEntry.date ) lastEntryDate = new Date(lastEntry.date);
+        res.setHeader('Last-Modified', lastEntryDate.toUTCString());
+      }
+
+      var ifModifiedSince = req.get('If-Modified-Since');
+
+      console.log('If-Modified-Since: ' + new Date(ifModifiedSince) + ' Last-Modified', lastEntryDate);
+
+      if (lastEntryDate !== null && ifModifiedSince !== null && lastEntryDate.getTime() <= new Date(ifModifiedSince).getTime()) {
+        res.status(304).send({status:304, message: 'Not modified', type:'internal'});
+        return;
+      }
+
       // if no error, format the payload
       // The general pattern here is to create an output stream that reformats
       // the data correctly into the desired representation.