prometheus/vendor/github.com/influxdata/influxdb/client/v2/client.go
2017-04-03 12:38:05 +02:00

610 lines
15 KiB
Go

// Package client (v2) is the current official Go client for InfluxDB.
package client // import "github.com/influxdata/influxdb/client/v2"
import (
"bytes"
"crypto/tls"
"encoding/json"
"errors"
"fmt"
"io"
"io/ioutil"
"net/http"
"net/url"
"strconv"
"strings"
"time"
"github.com/influxdata/influxdb/models"
)
// HTTPConfig is the config data needed to create an HTTP Client.
type HTTPConfig struct {
// Addr should be of the form "http://host:port"
// or "http://[ipv6-host%zone]:port".
Addr string
// Username is the influxdb username, optional.
Username string
// Password is the influxdb password, optional.
Password string
// UserAgent is the http User Agent, defaults to "InfluxDBClient".
UserAgent string
// Timeout for influxdb writes, defaults to no timeout.
Timeout time.Duration
// InsecureSkipVerify gets passed to the http client, if true, it will
// skip https certificate verification. Defaults to false.
InsecureSkipVerify bool
// TLSConfig allows the user to set their own TLS config for the HTTP
// Client. If set, this option overrides InsecureSkipVerify.
TLSConfig *tls.Config
}
// BatchPointsConfig is the config data needed to create an instance of the BatchPoints struct.
type BatchPointsConfig struct {
// Precision is the write precision of the points, defaults to "ns".
Precision string
// Database is the database to write points to.
Database string
// RetentionPolicy is the retention policy of the points.
RetentionPolicy string
// Write consistency is the number of servers required to confirm write.
WriteConsistency string
}
// Client is a client interface for writing & querying the database.
type Client interface {
// Ping checks that status of cluster, and will always return 0 time and no
// error for UDP clients.
Ping(timeout time.Duration) (time.Duration, string, error)
// Write takes a BatchPoints object and writes all Points to InfluxDB.
Write(bp BatchPoints) error
// Query makes an InfluxDB Query on the database. This will fail if using
// the UDP client.
Query(q Query) (*Response, error)
// Close releases any resources a Client may be using.
Close() error
}
// NewHTTPClient returns a new Client from the provided config.
// Client is safe for concurrent use by multiple goroutines.
func NewHTTPClient(conf HTTPConfig) (Client, error) {
if conf.UserAgent == "" {
conf.UserAgent = "InfluxDBClient"
}
u, err := url.Parse(conf.Addr)
if err != nil {
return nil, err
} else if u.Scheme != "http" && u.Scheme != "https" {
m := fmt.Sprintf("Unsupported protocol scheme: %s, your address"+
" must start with http:// or https://", u.Scheme)
return nil, errors.New(m)
}
tr := &http.Transport{
TLSClientConfig: &tls.Config{
InsecureSkipVerify: conf.InsecureSkipVerify,
},
}
if conf.TLSConfig != nil {
tr.TLSClientConfig = conf.TLSConfig
}
return &client{
url: *u,
username: conf.Username,
password: conf.Password,
useragent: conf.UserAgent,
httpClient: &http.Client{
Timeout: conf.Timeout,
Transport: tr,
},
transport: tr,
}, nil
}
// Ping will check to see if the server is up with an optional timeout on waiting for leader.
// Ping returns how long the request took, the version of the server it connected to, and an error if one occurred.
func (c *client) Ping(timeout time.Duration) (time.Duration, string, error) {
now := time.Now()
u := c.url
u.Path = "ping"
req, err := http.NewRequest("GET", u.String(), nil)
if err != nil {
return 0, "", err
}
req.Header.Set("User-Agent", c.useragent)
if c.username != "" {
req.SetBasicAuth(c.username, c.password)
}
if timeout > 0 {
params := req.URL.Query()
params.Set("wait_for_leader", fmt.Sprintf("%.0fs", timeout.Seconds()))
req.URL.RawQuery = params.Encode()
}
resp, err := c.httpClient.Do(req)
if err != nil {
return 0, "", err
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return 0, "", err
}
if resp.StatusCode != http.StatusNoContent {
var err = fmt.Errorf(string(body))
return 0, "", err
}
version := resp.Header.Get("X-Influxdb-Version")
return time.Since(now), version, nil
}
// Close releases the client's resources.
func (c *client) Close() error {
c.transport.CloseIdleConnections()
return nil
}
// client is safe for concurrent use as the fields are all read-only
// once the client is instantiated.
type client struct {
// N.B - if url.UserInfo is accessed in future modifications to the
// methods on client, you will need to syncronise access to url.
url url.URL
username string
password string
useragent string
httpClient *http.Client
transport *http.Transport
}
// BatchPoints is an interface into a batched grouping of points to write into
// InfluxDB together. BatchPoints is NOT thread-safe, you must create a separate
// batch for each goroutine.
type BatchPoints interface {
// AddPoint adds the given point to the Batch of points.
AddPoint(p *Point)
// AddPoints adds the given points to the Batch of points.
AddPoints(ps []*Point)
// Points lists the points in the Batch.
Points() []*Point
// Precision returns the currently set precision of this Batch.
Precision() string
// SetPrecision sets the precision of this batch.
SetPrecision(s string) error
// Database returns the currently set database of this Batch.
Database() string
// SetDatabase sets the database of this Batch.
SetDatabase(s string)
// WriteConsistency returns the currently set write consistency of this Batch.
WriteConsistency() string
// SetWriteConsistency sets the write consistency of this Batch.
SetWriteConsistency(s string)
// RetentionPolicy returns the currently set retention policy of this Batch.
RetentionPolicy() string
// SetRetentionPolicy sets the retention policy of this Batch.
SetRetentionPolicy(s string)
}
// NewBatchPoints returns a BatchPoints interface based on the given config.
func NewBatchPoints(conf BatchPointsConfig) (BatchPoints, error) {
if conf.Precision == "" {
conf.Precision = "ns"
}
if _, err := time.ParseDuration("1" + conf.Precision); err != nil {
return nil, err
}
bp := &batchpoints{
database: conf.Database,
precision: conf.Precision,
retentionPolicy: conf.RetentionPolicy,
writeConsistency: conf.WriteConsistency,
}
return bp, nil
}
type batchpoints struct {
points []*Point
database string
precision string
retentionPolicy string
writeConsistency string
}
func (bp *batchpoints) AddPoint(p *Point) {
bp.points = append(bp.points, p)
}
func (bp *batchpoints) AddPoints(ps []*Point) {
bp.points = append(bp.points, ps...)
}
func (bp *batchpoints) Points() []*Point {
return bp.points
}
func (bp *batchpoints) Precision() string {
return bp.precision
}
func (bp *batchpoints) Database() string {
return bp.database
}
func (bp *batchpoints) WriteConsistency() string {
return bp.writeConsistency
}
func (bp *batchpoints) RetentionPolicy() string {
return bp.retentionPolicy
}
func (bp *batchpoints) SetPrecision(p string) error {
if _, err := time.ParseDuration("1" + p); err != nil {
return err
}
bp.precision = p
return nil
}
func (bp *batchpoints) SetDatabase(db string) {
bp.database = db
}
func (bp *batchpoints) SetWriteConsistency(wc string) {
bp.writeConsistency = wc
}
func (bp *batchpoints) SetRetentionPolicy(rp string) {
bp.retentionPolicy = rp
}
// Point represents a single data point.
type Point struct {
pt models.Point
}
// NewPoint returns a point with the given timestamp. If a timestamp is not
// given, then data is sent to the database without a timestamp, in which case
// the server will assign local time upon reception. NOTE: it is recommended to
// send data with a timestamp.
func NewPoint(
name string,
tags map[string]string,
fields map[string]interface{},
t ...time.Time,
) (*Point, error) {
var T time.Time
if len(t) > 0 {
T = t[0]
}
pt, err := models.NewPoint(name, models.NewTags(tags), fields, T)
if err != nil {
return nil, err
}
return &Point{
pt: pt,
}, nil
}
// String returns a line-protocol string of the Point.
func (p *Point) String() string {
return p.pt.String()
}
// PrecisionString returns a line-protocol string of the Point,
// with the timestamp formatted for the given precision.
func (p *Point) PrecisionString(precison string) string {
return p.pt.PrecisionString(precison)
}
// Name returns the measurement name of the point.
func (p *Point) Name() string {
return p.pt.Name()
}
// Tags returns the tags associated with the point.
func (p *Point) Tags() map[string]string {
return p.pt.Tags().Map()
}
// Time return the timestamp for the point.
func (p *Point) Time() time.Time {
return p.pt.Time()
}
// UnixNano returns timestamp of the point in nanoseconds since Unix epoch.
func (p *Point) UnixNano() int64 {
return p.pt.UnixNano()
}
// Fields returns the fields for the point.
func (p *Point) Fields() (map[string]interface{}, error) {
return p.pt.Fields()
}
// NewPointFrom returns a point from the provided models.Point.
func NewPointFrom(pt models.Point) *Point {
return &Point{pt: pt}
}
func (c *client) Write(bp BatchPoints) error {
var b bytes.Buffer
for _, p := range bp.Points() {
if _, err := b.WriteString(p.pt.PrecisionString(bp.Precision())); err != nil {
return err
}
if err := b.WriteByte('\n'); err != nil {
return err
}
}
u := c.url
u.Path = "write"
req, err := http.NewRequest("POST", u.String(), &b)
if err != nil {
return err
}
req.Header.Set("Content-Type", "")
req.Header.Set("User-Agent", c.useragent)
if c.username != "" {
req.SetBasicAuth(c.username, c.password)
}
params := req.URL.Query()
params.Set("db", bp.Database())
params.Set("rp", bp.RetentionPolicy())
params.Set("precision", bp.Precision())
params.Set("consistency", bp.WriteConsistency())
req.URL.RawQuery = params.Encode()
resp, err := c.httpClient.Do(req)
if err != nil {
return err
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
if resp.StatusCode != http.StatusNoContent && resp.StatusCode != http.StatusOK {
var err = fmt.Errorf(string(body))
return err
}
return nil
}
// Query defines a query to send to the server.
type Query struct {
Command string
Database string
Precision string
Chunked bool
ChunkSize int
Parameters map[string]interface{}
}
// NewQuery returns a query object.
// The database and precision arguments can be empty strings if they are not needed for the query.
func NewQuery(command, database, precision string) Query {
return Query{
Command: command,
Database: database,
Precision: precision,
Parameters: make(map[string]interface{}),
}
}
// NewQueryWithParameters returns a query object.
// The database and precision arguments can be empty strings if they are not needed for the query.
// parameters is a map of the parameter names used in the command to their values.
func NewQueryWithParameters(command, database, precision string, parameters map[string]interface{}) Query {
return Query{
Command: command,
Database: database,
Precision: precision,
Parameters: parameters,
}
}
// Response represents a list of statement results.
type Response struct {
Results []Result
Err string `json:"error,omitempty"`
}
// Error returns the first error from any statement.
// It returns nil if no errors occurred on any statements.
func (r *Response) Error() error {
if r.Err != "" {
return fmt.Errorf(r.Err)
}
for _, result := range r.Results {
if result.Err != "" {
return fmt.Errorf(result.Err)
}
}
return nil
}
// Message represents a user message.
type Message struct {
Level string
Text string
}
// Result represents a resultset returned from a single statement.
type Result struct {
Series []models.Row
Messages []*Message
Err string `json:"error,omitempty"`
}
// Query sends a command to the server and returns the Response.
func (c *client) Query(q Query) (*Response, error) {
u := c.url
u.Path = "query"
jsonParameters, err := json.Marshal(q.Parameters)
if err != nil {
return nil, err
}
req, err := http.NewRequest("POST", u.String(), nil)
if err != nil {
return nil, err
}
req.Header.Set("Content-Type", "")
req.Header.Set("User-Agent", c.useragent)
if c.username != "" {
req.SetBasicAuth(c.username, c.password)
}
params := req.URL.Query()
params.Set("q", q.Command)
params.Set("db", q.Database)
params.Set("params", string(jsonParameters))
if q.Chunked {
params.Set("chunked", "true")
if q.ChunkSize > 0 {
params.Set("chunk_size", strconv.Itoa(q.ChunkSize))
}
}
if q.Precision != "" {
params.Set("epoch", q.Precision)
}
req.URL.RawQuery = params.Encode()
resp, err := c.httpClient.Do(req)
if err != nil {
return nil, err
}
defer resp.Body.Close()
var response Response
if q.Chunked {
cr := NewChunkedResponse(resp.Body)
for {
r, err := cr.NextResponse()
if err != nil {
// If we got an error while decoding the response, send that back.
return nil, err
}
if r == nil {
break
}
response.Results = append(response.Results, r.Results...)
if r.Err != "" {
response.Err = r.Err
break
}
}
} else {
dec := json.NewDecoder(resp.Body)
dec.UseNumber()
decErr := dec.Decode(&response)
// ignore this error if we got an invalid status code
if decErr != nil && decErr.Error() == "EOF" && resp.StatusCode != http.StatusOK {
decErr = nil
}
// If we got a valid decode error, send that back
if decErr != nil {
return nil, fmt.Errorf("unable to decode json: received status code %d err: %s", resp.StatusCode, decErr)
}
}
// If we don't have an error in our json response, and didn't get statusOK
// then send back an error
if resp.StatusCode != http.StatusOK && response.Error() == nil {
return &response, fmt.Errorf("received status code %d from server",
resp.StatusCode)
}
return &response, nil
}
// duplexReader reads responses and writes it to another writer while
// satisfying the reader interface.
type duplexReader struct {
r io.Reader
w io.Writer
}
func (r *duplexReader) Read(p []byte) (n int, err error) {
n, err = r.r.Read(p)
if err == nil {
r.w.Write(p[:n])
}
return n, err
}
// ChunkedResponse represents a response from the server that
// uses chunking to stream the output.
type ChunkedResponse struct {
dec *json.Decoder
duplex *duplexReader
buf bytes.Buffer
}
// NewChunkedResponse reads a stream and produces responses from the stream.
func NewChunkedResponse(r io.Reader) *ChunkedResponse {
resp := &ChunkedResponse{}
resp.duplex = &duplexReader{r: r, w: &resp.buf}
resp.dec = json.NewDecoder(resp.duplex)
resp.dec.UseNumber()
return resp
}
// NextResponse reads the next line of the stream and returns a response.
func (r *ChunkedResponse) NextResponse() (*Response, error) {
var response Response
if err := r.dec.Decode(&response); err != nil {
if err == io.EOF {
return nil, nil
}
// A decoding error happened. This probably means the server crashed
// and sent a last-ditch error message to us. Ensure we have read the
// entirety of the connection to get any remaining error text.
io.Copy(ioutil.Discard, r.duplex)
return nil, errors.New(strings.TrimSpace(r.buf.String()))
}
r.buf.Reset()
return &response, nil
}