my-rook-config/pkg/cephmgr/client/mon.go

/*
Copyright 2016 The Rook Authors. All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

Some of the code below came from https://github.com/digitalocean/ceph_exporter
which has the same license.
*/
package client

import (
	"encoding/json"
	"fmt"
)

func ExecuteMonCommand(connection Connection, cmd map[string]interface{}, message string) ([]byte, error) {
	response, _, err := ExecuteMonCommandWithInfo(connection, cmd, message)
	return response, err
}

func ExecuteMonCommandWithInfo(connection Connection, cmd map[string]interface{}, message string) ([]byte, string, error) {
	// ensure the json attribute is included in the request, unless already set
	if _, ok := cmd["format"]; !ok {
		cmd["format"] = "json"
	}

	prefix, ok := cmd["prefix"]
	if !ok {
		return nil, "", fmt.Errorf("missing prefix for the mon_command")
	}

	command, err := json.Marshal(cmd)
	if err != nil {
		return nil, "", fmt.Errorf("marshalling command %s failed: %+v", prefix, err)
	}

	logger.Debugf("mon_command: '%s'", string(command))

	response, info, err := connection.MonCommand(command)
	if err != nil {
		return nil, "", fmt.Errorf("mon_command %+v failed: %+v", cmd, err)
	}

	logger.Debugf("succeeded %s. info: %s", message, info)
	return response, info, err
}

// represents the response from a mon_status mon_command (subset of all available fields, only
// marshal ones we care about)
type MonStatusResponse struct {
	Quorum []int `json:"quorum"`
	MonMap struct {
		Mons []MonMapEntry `json:"mons"`
	} `json:"monmap"`
}

// request to simplify deserialization of a test request
type MonStatusRequest struct {
	Prefix string   `json:"prefix"`
	Format string   `json:"format"`
	ID     int      `json:"id"`
	Weight float32  `json:"weight"`
	Pool   string   `json:"pool"`
	Var    string   `json:"var"`
	Args   []string `json:"args"`
}

// represents an entry in the monitor map
type MonMapEntry struct {
	Name    string `json:"name"`
	Rank    int    `json:"rank"`
	Address string `json:"addr"`
}

// calls mon_status mon_command
func GetMonStatus(adminConn Connection) (MonStatusResponse, error) {
	cmd := map[string]interface{}{"prefix": "mon_status"}
	buf, err := ExecuteMonCommand(adminConn, cmd, fmt.Sprintf("retrieving mon_status"))

	var resp MonStatusResponse
	err = json.Unmarshal(buf, &resp)
	if err != nil {
		return MonStatusResponse{}, fmt.Errorf("unmarshall failed: %+v.  raw buffer response: %s", err, string(buf[:]))
	}

	return resp, nil
}

// MonStats is a subset of fields on the response from the mon command "status".  These fields
// are focused on monitor stats.
type MonStats struct {
	Health struct {
		Health struct {
			HealthServices []struct {
				Mons []struct {
					Name         string      `json:"name"`
					KBTotal      json.Number `json:"kb_total"`
					KBUsed       json.Number `json:"kb_used"`
					KBAvail      json.Number `json:"kb_avail"`
					AvailPercent json.Number `json:"avail_percent"`
					StoreStats   struct {
						BytesTotal json.Number `json:"bytes_total"`
						BytesSST   json.Number `json:"bytes_sst"`
						BytesLog   json.Number `json:"bytes_log"`
						BytesMisc  json.Number `json:"bytes_misc"`
					} `json:"store_stats"`
				} `json:"mons"`
			} `json:"health_services"`
		} `json:"health"`
		TimeChecks struct {
			Mons []struct {
				Name    string      `json:"name"`
				Skew    json.Number `json:"skew"`
				Latency json.Number `json:"latency"`
			} `json:"mons"`
		} `json:"timechecks"`
	} `json:"health"`
	Quorum []int `json:"quorum"`
}

func GetMonStats(conn Connection) (*MonStats, error) {
	// note this is another call to the mon command "status", but we'll be marshalling it into
	// a type with a different subset of fields, scoped to monitor stats
	cmd := map[string]interface{}{"prefix": "status"}
	buf, err := ExecuteMonCommand(conn, cmd, "status")
	if err != nil {
		return nil, fmt.Errorf("failed to get status: %+v", err)
	}

	var monStats MonStats
	if err := json.Unmarshal(buf, &monStats); err != nil {
		return nil, fmt.Errorf("failed to unmarshal status response: %+v", err)
	}

	return &monStats, nil
}