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# C# Native API

The Git repository for the C# Native API client is located [here](https://github.com/apache/iotdb-client-csharp/)

## Installation

### Install from NuGet Package

We have prepared Nuget Package for C# users. Users can directly install the client through .NET CLI. [The link of our NuGet Package is here](https://www.nuget.org/packages/Apache.IoTDB/). Run the following command in the command line to complete installation

```sh
dotnet add package Apache.IoTDB
```

Note that the `Apache.IoTDB` package only supports versions of the `.net framework 4.6.1` greater than `4.6.1`.

## Prerequisites

    .NET SDK Version >= 5.0 
    .NET Framework >= 4.6.1

## How to Use the Client (Quick Start)

Users can quickly get started by referring to the use cases under the [Apache-IoTDB-Client-CSharp-UserCase](https://github.com/apache/iotdb-client-csharp/tree/main/Apache-IoTDB-Client-CSharp-UserCase) directory in the [iotdb-client-csharp Git repository](https://github.com/apache/iotdb-client-csharp). These use cases serve as a useful resource for getting familiar with the client's functionality and capabilities.

For those who wish to delve deeper into the client's usage and explore more advanced features, the [samples](https://github.com/apache/iotdb-client-csharp/tree/main/samples/Apache.IoTDB.Samples) directory in the same repository contains additional code samples. 

## Developer environment requirements for iotdb-client-csharp

```
.NET SDK Version >= 5.0
.NET Framework >= 4.6.1
ApacheThrift >= 0.14.1
NLog >= 4.7.9
```

### OS

* Linux, Macos or other unix-like OS
* Windows+bash(WSL, cygwin, Git Bash)

### Command Line Tools

* dotnet CLI
* Thrift

## Basic interface description

The Session interface is semantically identical to other language clients

```csharp
// Parameters
string host = "localhost";
int port = 6667;
int pool_size = 2;

// Init Session
var session_pool = new SessionPool(host, port, pool_size);

// Open Session
await session_pool.Open(false);

// Create TimeSeries 
await session_pool.CreateTimeSeries("root.test_group.test_device.ts1", TSDataType.TEXT, TSEncoding.PLAIN, Compressor.UNCOMPRESSED);
await session_pool.CreateTimeSeries("root.test_group.test_device.ts2", TSDataType.BOOLEAN, TSEncoding.PLAIN, Compressor.UNCOMPRESSED);
await session_pool.CreateTimeSeries("root.test_group.test_device.ts3", TSDataType.INT32, TSEncoding.PLAIN, Compressor.UNCOMPRESSED);

// Insert Record
var measures = new List<string>{"ts1", "ts2", "ts3"};
var values = new List<object> { "test_text", true, (int)123 };
var timestamp = 1;
var rowRecord = new RowRecord(timestamp, values, measures);
await session_pool.InsertRecordAsync("root.test_group.test_device", rowRecord);

// Insert Tablet
var timestamp_lst = new List<long>{ timestamp + 1 };
var value_lst = new List<object> {"iotdb", true, (int) 12};
var tablet = new Tablet("root.test_group.test_device", measures, value_lst, timestamp_ls);
await session_pool.InsertTabletAsync(tablet);

// Close Session
await session_pool.Close();
```

### **Row Record**

- Encapsulate and abstract the `record` data in **IoTDB**
- e.g.

| timestamp | status | temperature |
| --------- | ------ | ----------- |
| 1         | 0      | 20          |

- Construction：

```csharp
var rowRecord = 
  new RowRecord(long timestamp, List<object> values, List<string> measurements);
```

### **Tablet**

- A data structure similar to a table, containing several non-empty data blocks of a device's rows。
- e.g.

| time | status | temperature |
| ---- | ------ | ----------- |
| 1    | 0      | 20          |
| 2    | 0      | 20          |
| 3    | 3      | 21          |

- Construction：

```csharp
var tablet = 
  Tablet(string deviceId,  List<string> measurements, List<List<object>> values, List<long> timestamps);
```

## **API**

### **Basic API**

| api name       | parameters                | notes                    | use example                        |
| -------------- | ------------------------- | ------------------------ |------------------------------------|
| Open           | bool                      | open session             | session_pool.Open(false)           |
| Close          | null                      | close session            | session_pool.Close()               |
| IsOpen         | null                      | check if session is open | session_pool.IsOpen()              |
| OpenDebugMode  | LoggingConfiguration=null | open debug mode          | session_pool.OpenDebugMode()       |
| CloseDebugMode | null                      | close debug mode         | session_pool.CloseDebugMode()      |
| SetTimeZone    | string                    | set time zone            | session_pool.SetTimeZone("+08:00") |
| GetTimeZone    | null                      | get time zone            | session_pool.GetTimeZone()         |

### **Record API**

| api name                            | parameters                        | notes                               | use example                                                                                                                          |
|-------------------------------------|-----------------------------------|-------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------|
| InsertRecordAsync                   | string, RowRecord                 | insert single record                | session_pool.InsertRecordAsync("root.97209_TEST_CSHARP_CLIENT_GROUP.TEST_CSHARP_CLIENT_DEVICE", new RowRecord(1, values, measures)); |
| InsertRecordsAsync                  | List\<string\>, List\<RowRecord\> | insert records                      | session_pool.InsertRecordsAsync(device_ids, rowRecords)                                                                              |
| InsertRecordsOfOneDeviceAsync       | string, List\<RowRecord\>         | insert records of one device        | session_pool.InsertRecordsOfOneDeviceAsync(device_id, rowRecords)                                                                    |
| InsertRecordsOfOneDeviceSortedAsync | string, List\<RowRecord\>         | insert sorted records of one device | InsertRecordsOfOneDeviceSortedAsync(deviceId, sortedRowRecords);                                                                     |
| TestInsertRecordAsync               | string, RowRecord                 | test insert record                  | session_pool.TestInsertRecordAsync("root.97209_TEST_CSHARP_CLIENT_GROUP.TEST_CSHARP_CLIENT_DEVICE", rowRecord)                       |
| TestInsertRecordsAsync              | List\<string\>, List\<RowRecord\> | test insert record                  | session_pool.TestInsertRecordsAsync(device_ids, rowRecords)                                                                          |

### **Tablet API**

| api name               | parameters     | notes                | use example                                  |
| ---------------------- |----------------| -------------------- |----------------------------------------------|
| InsertTabletAsync      | Tablet         | insert single tablet | session_pool.InsertTabletAsync(tablet)       |
| InsertTabletsAsync     | List\<Tablet\> | insert tablets       | session_pool.InsertTabletsAsync(tablets)     |
| TestInsertTabletAsync  | Tablet         | test insert tablet   | session_pool.TestInsertTabletAsync(tablet)   |
| TestInsertTabletsAsync | List\<Tablet\> | test insert tablets  | session_pool.TestInsertTabletsAsync(tablets) |

### **SQL API**

| api name                      | parameters | notes                          | use example                                                                                                                                                                |
| ----------------------------- | ---------- | ------------------------------ |----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ExecuteQueryStatementAsync    | string     | execute sql query statement    | session_pool.ExecuteQueryStatementAsync("select * from root.97209_TEST_CSHARP_CLIENT_GROUP.TEST_CSHARP_CLIENT_DEVICE where time<15");                                      |
| ExecuteNonQueryStatementAsync | string     | execute sql nonquery statement | session_pool.ExecuteNonQueryStatementAsync( "create timeseries root.97209_TEST_CSHARP_CLIENT_GROUP.TEST_CSHARP_CLIENT_DEVICE.status with datatype=BOOLEAN,encoding=PLAIN") |

### **Scheam API**

| api name                   | parameters                                                                   | notes                       | use example                                                                                                      |
| -------------------------- |------------------------------------------------------------------------------| --------------------------- |------------------------------------------------------------------------------------------------------------------|
| SetStorageGroup            | string                                                                       | set storage group           | session_pool.SetStorageGroup("root.97209_TEST_CSHARP_CLIENT_GROUP_01")                                           |
| CreateTimeSeries           | string, TSDataType, TSEncoding, Compressor                                   | create time series          | session_pool.CreateTimeSeries("root.97209_TEST_CSHARP_CLIENT_GROUP_01", data_type, encoding, compressor)         |
| DeleteStorageGroupAsync    | string                                                                       | delete single storage group | session_pool.DeleteStorageGroupAsync("root.97209_TEST_CSHARP_CLIENT_GROUP_01")                                   |
| DeleteStorageGroupsAsync   | List\<string\>                                                               | delete storage group        | session_pool.DeleteStorageGroupAsync("root.97209_TEST_CSHARP_CLIENT_GROUP")                                      |
| CreateMultiTimeSeriesAsync | List\<string\>, List\<TSDataType\> , List\<TSEncoding\> , List\<Compressor\> | create multi time series    | session_pool.CreateMultiTimeSeriesAsync(ts_path_lst, data_type_lst, encoding_lst, compressor_lst);               |
| DeleteTimeSeriesAsync      | List\<string\>                                                               | delete time series          | session_pool.DeleteTimeSeriesAsync(ts_path_lst)                                                                  |
| DeleteTimeSeriesAsync      | string                                                                       | delete time series          | session_pool.DeleteTimeSeriesAsync("root.97209_TEST_CSHARP_CLIENT_GROUP_01")                                     |
| DeleteDataAsync            | List\<string\>, long, long                                                   | delete data                 | session_pool.DeleteDataAsync(ts_path_lst, 2, 3)                                                                  |

### **Other API**

| api name                   | parameters | notes                       | use example                                          |
| -------------------------- | ---------- | --------------------------- | ---------------------------------------------------- |
| CheckTimeSeriesExistsAsync | string     | check if time series exists | session_pool.CheckTimeSeriesExistsAsync(time series) |


[e.g.](https://github.com/apache/iotdb-client-csharp/tree/main/samples/Apache.IoTDB.Samples)

## SessionPool

In order to execute concurrent client requests, we provide a `SessionPool` for the native interface. 
Since `SessionPool` itself is a superset of `Session`, as soon as `SessionPool` is instantiated with a `pool_size` parameter set to 1, it reverts to the original `Session`.

We use the `ConcurrentQueue` data structure to encapsulate a client queue to maintain multiple connections with the server. 
When the `Open()` interface is called, a specified number of clients are created and stored in the queue. 
Synchronous access to the queue is achieved through the `System.Threading.Monitor` class.

When a request is executed, it will try to find an idle client connection from the Connection pool. 
If there is no idle connection, the program will wait until there is an idle connection available and use that.

When a connection is finished executing a request, it will automatically be returned to the pool and be available for processing other requests.