influxdata/influxdb-client-go

InfluxDB Client Go

This repository contains the Go client library for use with InfluxDB 2.x and Flux. InfluxDB 3.x users should instead use the lightweight v3 client library. InfluxDB 1.x users should use the v1 client library.

For ease of migration and a consistent query and write experience, v2 users should consider using InfluxQL and the v1 client library.

• Features
• Documentation
  • Examples
• How To Use
  • Installation
  • Basic Example
  • Writes in Detail
  • Queries in Detail
  • Parametrized Queries
  • Concurrency
  • Proxy and redirects
  • Checking Server State
• InfluxDB 1.8 API compatibility
• Contributing
• License

Features

• InfluxDB 2 client
  • Querying data
    • using the Flux language
    • into raw data, flux table representation
    • How to queries
  • Writing data using
    • Line Protocol
    • Data Point
    • Both asynchronous or synchronous ways
    • How to writes
  • InfluxDB 2 API
    • setup, ready, health
    • authotizations, users, organizations
    • buckets, delete
    • ...

Documentation

This section contains links to the client library documentation.

• Product documentation, Getting Started
• Examples
• API Reference
• Changelog

Examples

Examples for basic writing and querying data are shown below in this document

There are also other examples in the API docs:

• Client usage
• Management APIs

How To Use

Installation

Go 1.17 or later is required.

Go mod project

1. Add the latest version of the client package to your project dependencies (go.mod).

   go get github.com/influxdata/influxdb-client-go/v2
   

2. Add import github.com/influxdata/influxdb-client-go/v2 to your source code.

GOPATH project

go get github.com/influxdata/influxdb-client-go

Note: To have go get in the GOPATH mode, the environment variable GO111MODULE must have the off value.

Basic Example

The following example demonstrates how to write data to InfluxDB 2 and read them back using the Flux language:

package main

import (
    "context"
    "fmt"
    "time"

    "github.com/influxdata/influxdb-client-go/v2"
)

func main() {
    // Create a new client using an InfluxDB server base URL and an authentication token
    client := influxdb2.NewClient("http://localhost:8086", "my-token")
    // Use blocking write client for writes to desired bucket
    writeAPI := client.WriteAPIBlocking("my-org", "my-bucket")
    // Create point using full params constructor
    p := influxdb2.NewPoint("stat",
        map[string]string{"unit": "temperature"},
        map[string]interface{}{"avg": 24.5, "max": 45.0},
        time.Now())
    // write point immediately
    writeAPI.WritePoint(context.Background(), p)
    // Create point using fluent style
    p = influxdb2.NewPointWithMeasurement("stat").
        AddTag("unit", "temperature").
        AddField("avg", 23.2).
        AddField("max", 45.0).
        SetTime(time.Now())
    err := writeAPI.WritePoint(context.Background(), p)
	if err != nil {
		panic(err)
	}
    // Or write directly line protocol
    line := fmt.Sprintf("stat,unit=temperature avg=%f,max=%f", 23.5, 45.0)
    err = writeAPI.WriteRecord(context.Background(), line)
	if err != nil {
		panic(err)
	}

    // Get query client
    queryAPI := client.QueryAPI("my-org")
    // Get parser flux query result
    result, err := queryAPI.Query(context.Background(), `from(bucket:"my-bucket")|> range(start: -1h) |> filter(fn: (r) => r._measurement == "stat")`)
    if err == nil {
        // Use Next() to iterate over query result lines
        for result.Next() {
            // Observe when there is new grouping key producing new table
            if result.TableChanged() {
                fmt.Printf("table: %s\n", result.TableMetadata().String())
            }
            // read result
            fmt.Printf("row: %s\n", result.Record().String())
        }
        if result.Err() != nil {
            fmt.Printf("Query error: %s\n", result.Err().Error())
        }
    } else {
		panic(err)
    }
    // Ensures background processes finishes
    client.Close()
}

Options

The InfluxDBClient uses set of options to configure behavior. These are available in the Options object Creating a client instance using

client := influxdb2.NewClient("http://localhost:8086", "my-token")

will use the default options.

To set different configuration values, e.g. to set gzip compression and trust all server certificates, get default options and change what is needed:

client := influxdb2.NewClientWithOptions("http://localhost:8086", "my-token",
    influxdb2.DefaultOptions().
        SetUseGZip(true).
        SetTLSConfig(&tls.Config{
            InsecureSkipVerify: true,
        }))

Writes

Client offers two ways of writing, non-blocking and blocking.

Non-blocking write client

Non-blocking write client uses implicit batching. Data are asynchronously written to the underlying buffer and they are automatically sent to a server when the size of the write buffer reaches the batch size, default 5000, or the flush interval, default 1s, times out. Writes are automatically retried on server back pressure.

This write client also offers synchronous blocking method to ensure that write buffer is flushed and all pending writes are finished, see Flush() method. Always use Close() method of the client to stop all background processes.

Asynchronous write client is recommended for frequent periodic writes.

package main

import (
    "fmt"
    "math/rand"
    "time"

    "github.com/influxdata/influxdb-client-go/v2"
)

func main() {
    // Create a new client using an InfluxDB server base URL and an authentication token
    // and set batch size to 20
    client := influxdb2.NewClientWithOptions("http://localhost:8086", "my-token",
        influxdb2.DefaultOptions().SetBatchSize(20))
    // Get non-blocking write client
    writeAPI := client.WriteAPI("my-org","my-bucket")
    // write some points
    for i := 0; i <100; i++ {
        // create point
        p := influxdb2.NewPoint(
            "system",
            map[string]string{
                "id":       fmt.Sprintf("rack_%v", i%10),
                "vendor":   "AWS",
                "hostname": fmt.Sprintf("host_%v", i%100),
            },
            map[string]interface{}{
                "temperature": rand.Float64() * 80.0,
                "disk_free":   rand.Float64() * 1000.0,
                "disk_total":  (i/10 + 1) * 1000000,
                "mem_total":   (i/100 + 1) * 10000000,
                "mem_free":    rand.Uint64(),
            },
            time.Now())
        // write asynchronously
        writeAPI.WritePoint(p)
    }
    // Force all unwritten data to be sent
    writeAPI.Flush()
    // Ensures background processes finishes
    client.Close()
}

Handling of failed async writes

WriteAPI by default continues with retrying of failed writes. Retried are automatically writes that fail on a connection failure or when server returns response HTTP status code >= 429.

Retrying algorithm uses random exponential strategy to set retry time. The delay for the next retry attempt is a random value in the interval retryInterval * exponentialBase^(attempts) and retryInterval * exponentialBase^(attempts+1). If writes of batch repeatedly fails, WriteAPI continues with retrying until maxRetries is reached or the overall retry time of batch exceeds maxRetryTime.

The defaults parameters (part of the WriteOptions) are:

• retryInterval=5,000ms
• exponentialBase=2
• maxRetryDelay=125,000ms
• maxRetries=5
• maxRetryTime=180,000ms

Retry delays are by default randomly distributed within the ranges:

1. 5,000-10,000
2. 10,000-20,000
3. 20,000-40,000
4. 40,000-80,000
5. 80,000-125,000

Setting retryInterval to 0 disables retry strategy and any failed write will discard the batch.

WriteFailedCallback allows advanced controlling of retrying. It is synchronously notified in case async write fails. It controls further batch handling by its return value. If it returns true, WriteAPI continues with retrying of writes of this batch. Returned false means the batch should be discarded.

Reading async errors

WriteAPI automatically logs write errors. Use Errors() method, which returns the channel for reading errors occuring during async writes, for writing write error to a custom target:

package main

import (
    "fmt"
    "math/rand"
    "time"

    "github.com/influxdata/influxdb-client-go/v2"
)

func main() {
    // Create a new client using an InfluxDB server base URL and an authentication token
    client := influxdb2.NewClient("http://localhost:8086", "my-token")
    // Get non-blocking write client
    writeAPI := client.WriteAPI("my-org", "my-bucket")
    // Get errors channel
    errorsCh := writeAPI.Errors()
    // Create go proc for reading and logging errors
    go func() {
        for err := range errorsCh {
            fmt.Printf("write error: %s\n", err.Error())
        }
    }()
    // write some points
    for i := 0; i < 100; i++ {
        // create point
        p := influxdb2.NewPointWithMeasurement("stat").
            AddTag("id", fmt.Sprintf("rack_%v", i%10)).
            AddTag("vendor", "AWS").
            AddTag("hostname", fmt.Sprintf("host_%v", i%100)).
            AddField("temperature", rand.Float64()*80.0).
            AddField("disk_free", rand.Float64()*1000.0).
            AddField("disk_total", (i/10+1)*1000000).
            AddField("mem_total", (i/100+1)*10000000).
            AddField("mem_free", rand.Uint64()).
            SetTime(time.Now())
        // write asynchronously
        writeAPI.WritePoint(p)
    }
    // Force all unwritten data to be sent
    writeAPI.Flush()
    // Ensures background processes finishes
    client.Close()
}

Blocking write client

Blocking write client writes given point(s) synchronously. It doesn't do implicit batching. Batch is created from given set of points. Implicit batching can be enabled with WriteAPIBlocking.EnableBatching().

package main

import (
    "context"
    "fmt"
    "math/rand"
    "time"

    "github.com/influxdata/influxdb-client-go/v2"
)

func main() {
    // Create a new client using an InfluxDB server base URL and an authentication token
    client := influxdb2.NewClient("http://localhost:8086", "my-token")
    // Get blocking write client
    writeAPI := client.WriteAPIBlocking("my-org","my-bucket")
    // write some points
    for i := 0; i <100; i++ {
        // create data point
        p := influxdb2.NewPoint(
            "system",
            map[string]string{
                "id":       fmt.Sprintf("rack_%v", i%10),
                "vendor":   "AWS",
                "hostname": fmt.Sprintf("host_%v", i%100),
            },
            map[string]interface{}{
                "temperature": rand.Float64() * 80.0,
                "disk_free":   rand.Float64() * 1000.0,
                "disk_total":  (i/10 + 1) * 1000000,
                "mem_total":   (i/100 + 1) * 10000000,
                "mem_free":    rand.Uint64(),
            },
            time.Now())
        // write synchronously
        err := writeAPI.WritePoint(context.Background(), p)
        if err != nil {
            panic(err)
        }
    }
    // Ensures background processes finishes
    client.Close()
}

Queries

Query client offers retrieving of query results to a parsed representation in a QueryTableResult or to a raw string.

QueryTableResult

QueryTableResult offers comfortable way how to deal with flux query CSV response. It parses CSV stream into FluxTableMetaData, FluxColumn and FluxRecord objects for easy reading the result.

package main

import (
    "context"
    "fmt"

    "github.com/influxdata/influxdb-client-go/v2"
)

func main() {
    // Create a new client using an InfluxDB server base URL and an authentication token
    client := influxdb2.NewClient("http://localhost:8086", "my-token")
    // Get query client
    queryAPI := client.QueryAPI("my-org")
    // get QueryTableResult
    result, err := queryAPI.Query(context.Background(), `from(bucket:"my-bucket")|> range(start: -1h) |> filter(fn: (r) => r._measurement == "stat")`)
    if err == nil {
        // Iterate over query response
        for result.Next() {
            // Notice when group key has changed
            if result.TableChanged() {
                fmt.Printf("table: %s\n", result.TableMetadata().String())
            }
            // Access data
            fmt.Printf("value: %v\n", result.Record().Value())
        }
        // check for an error
        if result.Err() != nil {
            fmt.Printf("query parsing error: %s\n", result.Err().Error())
        }
    } else {
        panic(err)
    }
    // Ensures background processes finishes
    client.Close()
}

Raw

QueryRaw() returns raw, unparsed, query result string and process it on your own. Returned csv format can be controlled by the third parameter, query dialect.

package main

import (
    "context"
    "fmt"

    "github.com/influxdata/influxdb-client-go/v2"
)

func main() {
    // Create a new client using an InfluxDB server base URL and an authentication token
    client := influxdb2.NewClient("http://localhost:8086", "my-token")
    // Get query client
    queryAPI := client.QueryAPI("my-org")
    // Query and get complete result as a string
    // Use default dialect
    result, err := queryAPI.QueryRaw(context.Background(), `from(bucket:"my-bucket")|> range(start: -1h) |> filter(fn: (r) => r._measurement == "stat")`, influxdb2.DefaultDialect())
    if err == nil {
        fmt.Println("QueryResult:")
        fmt.Println(result)
    } else {
        panic(err)
    }
    // Ensures background processes finishes
    client.Close()
}

Parametrized Queries

InfluxDB Cloud supports Parameterized Queries that let you dynamically change values in a query using the InfluxDB API. Parameterized queries make Flux queries more reusable and can also be used to help prevent injection attacks.

InfluxDB Cloud inserts the params object into the Flux query as a Flux record named params. Use dot or bracket notation to access parameters in the params record in your Flux query. Parameterized Flux queries support only int , float, and string data types. To convert the supported data types into other Flux basic data types, use Flux type conversion functions.

Query parameters can be passed as a struct or map. Param values can be only simple types or time.Time. The name of the parameter represented by a struct field can be specified by JSON annotation.

Parameterized query example:

:warning: Parameterized Queries are supported only in InfluxDB Cloud. There is no support in InfluxDB OSS currently.

package main

import (
	"context"
	"fmt"

	"github.com/influxdata/influxdb-client-go/v2"
)

func main() {
	// Create a new client using an InfluxDB server base URL and an authentication token
	client := influxdb2.NewClient("http://localhost:8086", "my-token")
	// Get query client
	queryAPI := client.QueryAPI("my-org")
	// Define parameters
	parameters := struct {
		Start string  `json:"start"`
		Field string  `json:"field"`
		Value float64 `json:"value"`
	}{
		"-1h",
		"temperature",
		25,
	}
	// Query with parameters
	query := `from(bucket:"my-bucket")
				|> range(start: duration(params.start))
				|> filter(fn: (r) => r._measurement == "stat")
				|> filter(fn: (r) => r._field == params.field)
				|> filter(fn: (r) => r._value > params.value)`

	// Get result
	result, err := queryAPI.QueryWithParams(context.Background(), query, parameters)
	if err == nil {
		// Iterate over query response
		for result.Next() {
			// Notice when group key has changed
			if result.TableChanged() {
				fmt.Printf("table: %s\n", result.TableMetadata().String())
			}
			// Access data
			fmt.Printf("value: %v\n", result.Record().Value())
		}
		// check for an error
		if result.Err() != nil {
			fmt.Printf("query parsing error: %s\n", result.Err().Error())
		}
	} else {
		panic(err)
	}
	// Ensures background processes finishes
	client.Close()
}

Concurrency

InfluxDB Go Client can be used in a concurrent environment. All its functions are thread-safe.

The best practise is to use a single Client instance per server URL. This ensures optimized resources usage, most importantly reusing HTTP connections.

For efficient reuse of HTTP resources among multiple clients, create an HTTP client and use Options.SetHTTPClient() for setting it to all clients:

    // Create HTTP client
    httpClient := &http.Client{
        Timeout: time.Second * time.Duration(60),
        Transport: &http.Transport{
            DialContext: (&net.Dialer{
                Timeout: 5 * time.Second,
            }).DialContext,
            TLSHandshakeTimeout: 5 * time.Second,
            TLSClientConfig: &tls.Config{
                InsecureSkipVerify: true,
            },
            MaxIdleConns:        100,
            MaxIdleConnsPerHost: 100,
            IdleConnTimeout:     90 * time.Second,
        },
    }
    // Client for server 1
    client1 := influxdb2.NewClientWithOptions("https://server:8086", "my-token", influxdb2.DefaultOptions().SetHTTPClient(httpClient))
    // Client for server 2
    client2 := influxdb2.NewClientWithOptions("https://server:9999", "my-token2", influxdb2.DefaultOptions().SetHTTPClient(httpClient))

Client ensures that there is a single instance of each server API sub-client for the specific area. E.g. a single WriteAPI instance for each org/bucket pair, a single QueryAPI for each org.

Such a single API sub-client instance can be used concurrently:

package main

import (
	"math/rand"
	"sync"
	"time"

	influxdb2 "github.com/influxdata/influxdb-client-go"
	"github.com/influxdata/influxdb-client-go/v2/api/write"
)

func main() {
    // Create client
    client := influxdb2.NewClient("http://localhost:8086", "my-token")
    // Ensure closing the client
    defer client.Close()

    // Get write client
    writeApi := client.WriteAPI("my-org", "my-bucket")

    // Create channel for points feeding
    pointsCh := make(chan *write.Point, 200)

    threads := 5

    var wg sync.WaitGroup
    go func(points int) {
        for i := 0; i < points; i++ {
            p := influxdb2.NewPoint("meas",
                map[string]string{"tag": "tagvalue"},
                map[string]interface{}{"val1": rand.Int63n(1000), "val2": rand.Float64()*100.0 - 50.0},
                time.Now())
            pointsCh <- p
        }
        close(pointsCh)
    }(1000000)

    // Launch write routines
    for t := 0; t < threads; t++ {
        wg.Add(1)
        go func() {
            for p := range pointsCh {
                writeApi.WritePoint(p)
            }
            wg.Done()
        }()
    }
    // Wait for writes complete
    wg.Wait()
}

Proxy and redirects

You can configure InfluxDB Go client behind a proxy in two ways:

1. Using environment variable Set environment variable HTTP_PROXY (or HTTPS_PROXY based on the scheme of your server url). e.g. (linux) export HTTP_PROXY=http://my-proxy:8080 or in Go code os.Setenv("HTTP_PROXY","http://my-proxy:8080")

2. Configure http.Client to use proxy
   Create a custom http.Client with a proxy configuration:

   proxyUrl, err := url.Parse("http://my-proxy:8080")
   httpClient := &http.Client{
       Transport: &http.Transport{
           Proxy: http.ProxyURL(proxyUrl)
       }
   }
   client := influxdb2.NewClientWithOptions("http://localhost:8086", token, influxdb2.DefaultOptions().SetHTTPClient(httpClient))
   

Client automatically follows HTTP redirects. The default redirect policy is to follow up to 10 consecutive requests. Due to a security reason Authorization header is not forwarded when redirect leads to a different domain. To overcome this limitation you have to set a custom redirect handler:

token := "my-token"

httpClient := &http.Client{
    CheckRedirect: func(req *http.Request, via []*http.Request) error {
        req.Header.Add("Authorization","Token " + token)
        return nil
    },
}
client := influxdb2.NewClientWithOptions("http://localhost:8086", token, influxdb2.DefaultOptions().SetHTTPClient(httpClient))

Checking Server State

There are three functions for checking whether a server is up and ready for communication:

Only the Ping() function works in InfluxDB Cloud server.

InfluxDB 1.8 API compatibility

InfluxDB 1.8.0 introduced forward compatibility APIs for InfluxDB 2.0. This allow you to easily move from InfluxDB 1.x to InfluxDB 2.0 Cloud or open source.

Client API usage differences summary:

1. Use the form username:password for an authentication token. Example: my-user:my-password. Use an empty string ("") if the server doesn't require authentication.
2. The organization parameter is not used. Use an empty string ("") where necessary.
3. Use the form database/retention-policy where a bucket is required. Skip retention policy if the default retention policy should be used. Examples: telegraf/autogen, telegraf.  

The following forward compatible APIs are available:

Example

package main

import (
    "context"
    "fmt"
    "time"

    "github.com/influxdata/influxdb-client-go/v2"
)

func main() {
    userName := "my-user"
    password := "my-password"
     // Create a new client using an InfluxDB server base URL and an authentication token
    // For authentication token supply a string in the form: "username:password" as a token. Set empty value for an unauthenticated server
    client := influxdb2.NewClient("http://localhost:8086", fmt.Sprintf("%s:%s",userName, password))
    // Get the blocking write client
    // Supply a string in the form database/retention-policy as a bucket. Skip retention policy for the default one, use just a database name (without the slash character)
    // Org name is not used
    writeAPI := client.WriteAPIBlocking("", "test/autogen")
    // create point using full params constructor
    p := influxdb2.NewPoint("stat",
        map[string]string{"unit": "temperature"},
        map[string]interface{}{"avg": 24.5, "max": 45},
        time.Now())
    // Write data
    err := writeAPI.WritePoint(context.Background(), p)
    if err != nil {
        fmt.Printf("Write error: %s\n", err.Error())
    }

    // Get query client. Org name is not used
    queryAPI := client.QueryAPI("")
    // Supply string in a form database/retention-policy as a bucket. Skip retention policy for the default one, use just a database name (without the slash character)
    result, err := queryAPI.Query(context.Background(), `from(bucket:"test")|> range(start: -1h) |> filter(fn: (r) => r._measurement == "stat")`)
    if err == nil {
        for result.Next() {
            if result.TableChanged() {
                fmt.Printf("table: %s\n", result.TableMetadata().String())
            }
            fmt.Printf("row: %s\n", result.Record().String())
        }
        if result.Err() != nil {
            fmt.Printf("Query error: %s\n", result.Err().Error())
        }
    } else {
        fmt.Printf("Query error: %s\n", err.Error())
    }
    // Close client
    client.Close()
}

Contributing

If you would like to contribute code you can do through GitHub by forking the repository and sending a pull request into the master branch.

License

The InfluxDB 2 Go Client is released under the MIT License.