baseapi/platformapi/platformapi.go

package platformapi

import (
	"bytes"
	"errors"
	"io"
	"io/ioutil"
	"net"
	"net/http"
	"net/url"
	"strings"
	"time"

	"git.rosy.net.cn/baseapi"
	"git.rosy.net.cn/baseapi/utils"
	"github.com/fatih/structs"
)

const (
	DefClientTimeout              = 10 * time.Second
	DefSleepSecondWhenExceedLimit = 3 * time.Second
	DefRandSlice                  = 10
	DefMaxRecoverableRetryCount   = 3
	DefMaxExceedLimitRetryCount   = 25
)

type APIRetryConfig struct {
	MaxExceedLimitRetryCount   int
	MaxRecoverableRetryCount   int
	SleepSecondWhenExceedLimit time.Duration
}

type APIConfig struct {
	APIRetryConfig
	ClientTimeout time.Duration
}

type AccessPlatformAPIWithRetryParam struct {
	APIRetryConfig
	Client  *http.Client
	Request *http.Request
}

var (
	DefAPIConfig = APIConfig{
		APIRetryConfig: APIRetryConfig{
			MaxExceedLimitRetryCount:   DefMaxExceedLimitRetryCount,
			MaxRecoverableRetryCount:   DefMaxRecoverableRetryCount,
			SleepSecondWhenExceedLimit: DefSleepSecondWhenExceedLimit,
		},
		ClientTimeout: DefClientTimeout,
	}
)

const (
	ErrLevelSuccess        = "JXC4_SUCCESS"
	ErrLevelExceedLimit    = "JXC4_EXCEED_LIMIT"
	ErrLevelRecoverableErr = "JXC4_RECOVERABLE"
	ErrLevelGeneralFail    = "JXC4_GENERAL_FAIL"
	ErrLevelCodeIsNotOK    = "JXC4_CODE_IS_NOT_OK"
)

const (
	maxDataSizeDontOutput = 20 * 1024
)

// common api access error
var (
	ErrAPIAccessFailed         = errors.New("access API failed")
	ErrHTTPCodeIsNot200        = errors.New("HTTP code is not 200")
	ErrResponseDataFormatWrong = errors.New("the data of response has wrong format")
)

// common callback response
var (
	ErrStrUnescapeError            = "can not unescape data:%v, error:%v"
	ErrStrUnmarshalError           = "can not unmarshal data:%v, error:%v"
	ErrStrCallbackSignatureIsWrong = "wrong signature"
)

func init() {
	structs.DefaultTagName = "json"
}

func getClonedData(requestURL *url.URL, r *bytes.Buffer) string {
	if strings.Index(requestURL.String(), "uploadImg") >= 0 {
		return "binary content"
	}
	retVal := string(r.Bytes())
	if len(retVal) > maxDataSizeDontOutput {
		return "request data is too large"
	}
	return retVal
}

func AccessPlatformAPIWithRetry(client *http.Client, handleRequest func() *http.Request, config *APIConfig, handleResponse func(bodyMap map[string]interface{}) (string, error)) error {
	exceedLimitRetryCount := 0
	recoverableErrorRetryCount := 0
	for {
		savedBuf := new(bytes.Buffer)
		request := handleRequest()
		if request.Body != nil {
			request.Body = ioutil.NopCloser(io.TeeReader(request.Body, savedBuf))
		}
		beginTime := time.Now()
		trackID := utils.GetUUID()
		baseapi.SugarLogger.Debugf("begin AccessPlatformAPIWithRetry:%s do url:%v", trackID, request.URL)
		response, err := client.Do(request)
		baseapi.SugarLogger.Debugf("end AccessPlatformAPIWithRetry:%s do url:%v, request:%s", trackID, request.URL, getClonedData(request.URL, savedBuf))
		if err != nil {
			baseapi.SugarLogger.Debugf("AccessPlatformAPIWithRetry:%s client.Get return err:%v", err)
			err, ok := err.(net.Error)
			if ok && err.Timeout() && recoverableErrorRetryCount <= config.MaxRecoverableRetryCount {
				recoverableErrorRetryCount++
				continue
			} else {
				baseapi.SugarLogger.Errorf("AccessPlatformAPIWithRetry:%s access api url:%v, request:%v, error:%v", trackID, request.URL, getClonedData(request.URL, savedBuf), err)
				return ErrAPIAccessFailed
			}
		}
		usedMilliSecond := time.Now().Sub(beginTime) / time.Millisecond
		if usedMilliSecond > 5000 {
			baseapi.SugarLogger.Infof("AccessPlatformAPIWithRetry:%s access api too slow, url:%v, request:%v, usedMilliSecond:%d", trackID, request.URL, getClonedData(request.URL, savedBuf), usedMilliSecond)
		}
		defer response.Body.Close()
		if response.StatusCode != http.StatusOK {
			// todo, hardcode，暂时在这里处理饿百的访问异常
			if response.StatusCode == http.StatusBadRequest && request.URL.Hostname() == "api-be.ele.me" {
				recoverableErrorRetryCount++
				if recoverableErrorRetryCount <= config.MaxRecoverableRetryCount {
					continue
				}
			}
			if bodyData, err := ioutil.ReadAll(response.Body); err == nil {
				baseapi.SugarLogger.Errorf("AccessPlatformAPIWithRetry:%s HTTP code is:%d, url:%v, request:%v, response:%s", trackID, response.StatusCode, request.URL, getClonedData(request.URL, savedBuf), string(bodyData))
			} else {
				baseapi.SugarLogger.Errorf("AccessPlatformAPIWithRetry:%s HTTP code is:%d, url:%v, request:%v", trackID, response.StatusCode, request.URL, getClonedData(request.URL, savedBuf))
			}
			return ErrHTTPCodeIsNot200
		}
		var (
			errLevel string
			bodyMap  map[string]interface{}
		)
		bodyData, err := ioutil.ReadAll(response.Body)
		if err != nil {
			baseapi.SugarLogger.Errorf("AccessPlatformAPIWithRetry:%s url:%v, request:%v failed with error:%v", trackID, request.URL, getClonedData(request.URL, savedBuf), err)
		} else if err = utils.TryUnmarshalUseNumber(bodyData, &bodyMap); err != nil {
			baseapi.SugarLogger.Errorf("AccessPlatformAPIWithRetry:%s url:%v, request:%v failed with error:%v, bodyData:%s", trackID, request.URL, getClonedData(request.URL, savedBuf), err, string(bodyData))
		}

		if err != nil {
			errLevel = ErrLevelRecoverableErr // 读取数据错误，或数据格式错误认为是偶发情况，重试
		} else {
			errLevel, err = handleResponse(bodyMap)
		}
		baseapi.SugarLogger.Debugf("AccessPlatformAPIWithRetry:%s url:%v, response:%s", trackID, request.URL, utils.Format4Output(bodyMap, true))
		if err == nil {
			return nil
		} else if errLevel == ErrLevelExceedLimit {
			exceedLimitRetryCount++
			if exceedLimitRetryCount <= config.MaxExceedLimitRetryCount {
				time.Sleep(config.SleepSecondWhenExceedLimit)
				continue
			}
		} else if errLevel == ErrLevelRecoverableErr {
			recoverableErrorRetryCount++
			if recoverableErrorRetryCount <= config.MaxRecoverableRetryCount {
				continue
			}
		}
		baseapi.SugarLogger.Infof("AccessPlatformAPIWithRetry:%s failed, url:%v, response:%s, error:%v", trackID, request.URL, utils.Format4Output(bodyMap, true), err)
		return err
	}
}