GreptimeDB Go Ingester

Provide API to insert data into GreptimeDB.

How To Use

Installation

go get -u github.com/GreptimeTeam/greptimedb-ingester-go

Import

import greptime "github.com/GreptimeTeam/greptimedb-ingester-go"

Config

Initiate a Config for Client

cfg := greptime.NewConfig("<host>").
    WithPort(4001).
    WithAuth("<username>", "<password>").
    WithDatabase("<database>")

Options

Secure

cfg.WithInsecure(false) // default insecure=true

keepalive

cfg.WithKeepalive(time.Second*30, time.Second*5) // keepalive isn't enabled by default

Client

cli, err := greptime.NewClient(cfg)

Insert & StreamInsert

• you can Insert data into GreptimeDB via different style:

  • Table style
  • ORM style

• streaming insert is to Send data into GreptimeDB without waiting for response.

Table style

you can define schema via Table and Column, and then AddRow to include the real data you want to write.

define table schema, and add rows

import(
    "github.com/GreptimeTeam/greptimedb-ingester-go/table"
    "github.com/GreptimeTeam/greptimedb-ingester-go/table/types"
)

tbl, err := table.New("<table_name>")

tbl.AddTagColumn("id", types.INT64)
tbl.AddFieldColumn("host", types.STRING)
tbl.AddTimestampColumn("ts", types.TIMESTAMP_MILLISECOND)

err := tbl.AddRow(1, "127.0.0.1", time.Now())
err := tbl.AddRow(2, "127.0.0.2", time.Now())
...

Write into GreptimeDB

resp, err := cli.Write(context.Background(), tbl)

Delete from GreptimeDB

dtbl, err := table.New("<table_name>")
dtbl.AddTagColumn("id", types.INT64)
dtbl.AddTimestampColumn("ts", types.TIMESTAMP_MILLISECOND)

// timestamp is the time you want to delete row
err := dtbl.AddRow(1, "127.0.0.1",timestamp)

affected, err := cli.Delete(context.Background(),dtbl)

Stream Write into GreptimeDB

err := cli.StreamWrite(context.Background(), tbl)
...
affected, err := cli.CloseStream(ctx)

Stream Delete from GreptimeDB

err := cli.StreamDelete(context.Background(), tbl)
...
affected, err := cli.CloseStream(ctx)

ORM style

If you prefer ORM style, and define column-field relationship via struct field tag, you can try the following way.

Tag

• greptime is the struct tag key
• tag, field, timestamp is for SemanticType, and the value is ignored
• column is to define the column name
• type is to define the data type. if type is timestamp, precision is supported
• the metadata separator is ; and the key value separator is :

type supported is the same as described Datatypes supported, and case insensitive

define struct with tags

type Monitor struct {
    ID          int64     `greptime:"tag;column:id;type:int64"`
    Host        string    `greptime:"field;column:host;type:string"`
    Ts          time.Time `greptime:"timestamp;column:ts;type:timestamp;precision:millisecond"`
}

// TableName is to define the table name.
func (Monitor) TableName() string {
    return "<table_name>"
}

instance your struct

monitors := []Monitor{
    {
        ID:          randomId(),
        Host:        "127.0.0.1",
        Running:     true,
    },
    {
        ID:          randomId(),
        Host:        "127.0.0.2",
        Running:     true,
    },
}

WriteObject into GreptimeDB

resp, err := cli.WriteObject(context.Background(), monitors)

DeleteObject in GreptimeDB

deleteMonitors := monitors[:1]

affected, err := cli.DeleteObject(context.Background(), deleteMonitors)

Stream WriteObject into GreptimeDB

err := cli.StreamWriteObject(context.Background(), monitors)
...
affected, err := cli.CloseStream(ctx)

Stream DeleteObject in GreptimeDB

deleteMonitors := monitors[:1]

err := cli.StreamDeleteObject(context.Background(), deleteMonitors)
...
affected, err := cli.CloseStream(ctx)

Datatypes supported

The GreptimeDB column is for the datatypes supported in library, and the Go column is the matched Go type.

GreptimeDB	Go	Description
INT8	int8
INT16	int16
INT32	int32
INT64, INT	int64
UINT8	uint8
UINT16	uint16
UINT32	uint32
UINT64, UINT	uint64
FLOAT32	float32
FLOAT64, FLOAT	float64
BOOLEAN, BOOL	bool
STRING	string
BINARY, BYTES	[]byte
DATE	Int or time.Time	the day elapsed since 1970-1-1
DATETIME	Int or time.Time	the millisecond elapsed since 1970-1-1
TIMESTAMP_SECOND	Int or time.Time
TIMESTAMP_MILLISECOND, TIMESTAMP	Int or time.Time
TIMESTAMP_MICROSECOND	Int or time.Time
TIMESTAMP_NANOSECOND	Int or time.Time

NOTE: Int is for all of Integer and Unsigned Integer in Go

Query

You can use ORM library like gorm with MySQL or PostgreSQL driver to connect GreptimeDB and retrieve data from it.

type Monitor struct {
    ID          int64     `gorm:"primaryKey;column:id"`
    Host        string    `gorm:"column:host"`
    Ts          time.Time `gorm:"column:ts"`
}

// Get all monitors
var monitors []Monitor
result := db.Find(&monitors)