DOCSP-17732 time series page (#154)

* added time series page

Author: kyuan-mongodb

source/fundamentals.txt

@@ -23,6 +23,7 @@ Fundamentals
    /fundamentals/monitoring
    /fundamentals/gridfs
    /fundamentals/csfle
+   /fundamentals/time-series
 
 The Fundamentals section contains detailed information to help you
 expand your knowledge on how to use MongoDB with the Java driver. We

source/fundamentals/builders/aggregates.txt

@@ -538,6 +538,8 @@ The following example creates a pipeline stage that executes two parallel aggreg
    :language: java
    :dedent:
 
+.. _builders-aggregates-setWindowFields:
+
 SetWindowFields
 ---------------
 

source/fundamentals/time-series.txt

@@ -0,0 +1,107 @@
+=======================
+Time Series Collections
+=======================
+
+.. default-domain:: mongodb
+
+.. contents:: On this page
+   :local:
+   :backlinks: none
+   :depth: 1
+   :class: singlecol
+
+Overview
+--------
+
+In this guide, you can learn about **time series collections** in
+MongoDB, and how to interact with them in the MongoDB Java driver. 
+
+Time series collections efficiently store sequences of measurements over
+a period of time. Time series data consists of any data collected over
+time, metadata that describes the measurement, and the time of the
+measurement.
+
+.. list-table::
+   :widths: 33, 33, 33
+   :header-rows: 1
+   :stub-columns: 1
+
+   * - Example 
+     - Measurement
+     - Metadata
+
+   * - Sales Data
+     - Revenue
+     - Company
+
+   * - Infection Rates
+     - Amount of People Infected
+     - Location
+
+Create a Time Series Collection
+-------------------------------
+
+To create a time series collection, pass the following parameters to the
+`createCollection() <{+api+}/apidocs/mongodb-driver-sync/com/mongodb/client/MongoDatabase.html#createCollection(java.lang.String,com.mongodb.client.model.CreateCollectionOptions)>`__
+method: 
+
+- The name of the new collection to create
+- The `TimeSeriesOptions <{+api+}/apidocs/mongodb-driver-core/com/mongodb/client/model/TimeSeriesOptions.html>`__  for creating the collection in a `CreateCollectionOptions <{+api+}/apidocs/mongodb-driver-core/com/mongodb/client/model/CreateCollectionOptions.html>`__ object
+
+.. literalinclude:: /includes/fundamentals/code-snippets/TimeSeries.java
+   :start-after: begin time series
+   :end-before: end time series
+   :emphasize-lines: 5
+   :language: java
+   :dedent:
+
+.. important::
+
+   Versions prior to MongoDB 5.0 cannot create a time series collection.
+
+To check if you successfully created the collection, send the
+``"listCollections"`` command to the `runCommand() <{+api+}/apidocs/mongodb-driver-sync/com/mongodb/client/MongoDatabase.html#runCommand(org.bson.conversions.Bson)>`__ method.
+
+.. literalinclude:: /includes/fundamentals/code-snippets/TimeSeries.java
+   :start-after: begin check collection type
+   :end-before: end check collection type
+   :emphasize-lines: 1
+   :language: java
+   :dedent:
+
+Your output should look similar to the following:
+
+.. code-block:: json
+   :emphasize-lines: 7, 10
+
+   {
+    "id": <some number>,
+    "ns": "<db name>.$cmd.listCollections",
+    "firstBatch": [
+     {
+       "name": "<time series collection name>",
+       "type": "timeseries",
+       "options": {
+        "expireAfterSeconds": <some number>,
+         "timeseries": { ... }
+        },
+        ...
+      },
+      ...
+    ]
+   }
+
+Query a Time Series Collection
+------------------------------
+
+To query in a time series collection, use the same conventions as you
+would for :doc:`retrieving </fundamentals/crud/read-operations/retrieve>`
+and :ref:`aggregating data <java-aggregation>`. 
+
+.. note:: Window Functions
+
+   MongoDB version 5.0 introduces window functions into the aggregation
+   framework. You can use window functions to perform operations on a
+   contiguous span of time series data. For more information, see our
+   :ref:`Aggregates Builders guide <builders-aggregates-setWindowFields>`.
+   

source/includes/fundamentals/code-snippets/TimeSeries.java

@@ -0,0 +1,43 @@
+public package docs;
+
+import org.bson.BsonInt64;
+import org.bson.Document;
+
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+import com.mongodb.client.MongoDatabase;
+import com.mongodb.MongoException;
+import com.mongodb.client.model.CreateCollectionOptions;
+import com.mongodb.client.model.TimeSeriesOptions;
+
+import java.util.Arrays;
+import java.util.List;
+
+public class TimeSeriesCollection {
+    
+    public static void main(String[] args) {
+        
+        final String uri = System.getenv("DRIVER_REF_URI");
+
+        try(MongoClient mongoClient = MongoClients.create(uri)){
+
+            // begin time series
+            MongoDatabase database = mongoClient.getDatabase("fall_weather");
+            TimeSeriesOptions tsOptions = new TimeSeriesOptions("temperature");
+            CreateCollectionOptions collOptions = new CreateCollectionOptions().timeSeriesOptions(tsOptions);
+            
+            database.createCollection("september2021", collOptions);
+            // end time series
+            try {
+                // begin check collection type
+                Document commandResult = database.runCommand(new Document("listCollections", new BsonInt64(1)));
+                
+                List<String> keys = Arrays.asList("cursor");
+                System.out.println("listCollections: " + commandResult.getEmbedded(keys, Document.class).toJson());
+                // end check collection type
+            } catch (MongoException me) {
+                System.err.println("An error occurred: " + me);
+            }  
+        }     
+    }
+}