github.com/m3db/m3@v1.5.0/src/query/api/v1/handler/namespace/get.go (about)

     1  // Copyright (c) 2018 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package namespace
    22  
    23  import (
    24  	"bytes"
    25  	"fmt"
    26  	"net/http"
    27  	"path"
    28  	"strconv"
    29  
    30  	clusterclient "github.com/m3db/m3/src/cluster/client"
    31  	"github.com/m3db/m3/src/cluster/kv"
    32  	"github.com/m3db/m3/src/cluster/placementhandler/handleroptions"
    33  	nsproto "github.com/m3db/m3/src/dbnode/generated/proto/namespace"
    34  	"github.com/m3db/m3/src/query/api/v1/route"
    35  	"github.com/m3db/m3/src/query/generated/proto/admin"
    36  	"github.com/m3db/m3/src/query/util/logging"
    37  	"github.com/m3db/m3/src/x/instrument"
    38  	xhttp "github.com/m3db/m3/src/x/net/http"
    39  
    40  	"github.com/gogo/protobuf/jsonpb"
    41  	"github.com/golang/protobuf/proto"
    42  	"go.uber.org/zap"
    43  )
    44  
    45  var (
    46  	// M3DBGetURL is the url for the namespace get handler (with the GET method).
    47  	M3DBGetURL = path.Join(route.Prefix, M3DBServiceNamespacePathName)
    48  
    49  	// GetHTTPMethod is the HTTP method used with this resource.
    50  	GetHTTPMethod = http.MethodGet
    51  )
    52  
    53  const (
    54  	debugParam = "debug"
    55  )
    56  
    57  // GetHandler is the handler for namespace gets.
    58  type GetHandler Handler
    59  
    60  // NewGetHandler returns a new instance of GetHandler.
    61  func NewGetHandler(
    62  	client clusterclient.Client,
    63  	instrumentOpts instrument.Options,
    64  ) *GetHandler {
    65  	return &GetHandler{
    66  		client:         client,
    67  		instrumentOpts: instrumentOpts,
    68  	}
    69  }
    70  
    71  func (h *GetHandler) ServeHTTP(
    72  	svc handleroptions.ServiceNameAndDefaults,
    73  	w http.ResponseWriter,
    74  	r *http.Request,
    75  ) {
    76  	ctx := r.Context()
    77  	logger := logging.WithContext(ctx, h.instrumentOpts)
    78  	opts := handleroptions.NewServiceOptions(svc, r.Header, nil)
    79  	nsRegistry, err := h.Get(opts)
    80  
    81  	if err != nil {
    82  		logger.Error("unable to get namespace", zap.Error(err))
    83  		xhttp.WriteError(w, err)
    84  		return
    85  	}
    86  
    87  	resp := &admin.NamespaceGetResponse{
    88  		Registry: &nsRegistry,
    89  	}
    90  
    91  	if debug, err := strconv.ParseBool(r.URL.Query().Get(debugParam)); err == nil && debug {
    92  		nanosToDurationMap, err := nanosToDuration(resp)
    93  		if err != nil {
    94  			logger.Error("error converting nano fields to duration", zap.Error(err))
    95  			xhttp.WriteError(w, err)
    96  			return
    97  		}
    98  
    99  		xhttp.WriteJSONResponse(w, nanosToDurationMap, logger)
   100  		return
   101  	}
   102  
   103  	xhttp.WriteProtoMsgJSONResponse(w, resp, logger)
   104  }
   105  
   106  // Get gets the namespaces.
   107  func (h *GetHandler) Get(opts handleroptions.ServiceOptions) (nsproto.Registry, error) {
   108  	var emptyReg = nsproto.Registry{}
   109  
   110  	store, err := h.client.Store(opts.KVOverrideOptions())
   111  	if err != nil {
   112  		return emptyReg, err
   113  	}
   114  
   115  	value, err := store.Get(M3DBNodeNamespacesKey)
   116  
   117  	if err == kv.ErrNotFound {
   118  		// Having no namespace should not be treated as an error
   119  		return emptyReg, nil
   120  	} else if err != nil {
   121  		return emptyReg, err
   122  	}
   123  
   124  	var protoRegistry nsproto.Registry
   125  
   126  	if err := value.Unmarshal(&protoRegistry); err != nil {
   127  		return emptyReg, fmt.Errorf("failed to parse namespace version %v: %v", value.Version(), err)
   128  	}
   129  
   130  	return protoRegistry, nil
   131  }
   132  
   133  func nanosToDuration(resp proto.Message) (map[string]interface{}, error) {
   134  	marshaler := jsonpb.Marshaler{EmitDefaults: true}
   135  	buf := new(bytes.Buffer)
   136  	marshaler.Marshal(buf, resp)
   137  
   138  	toDuration, err := xhttp.NanosToDurationBytes(buf)
   139  	if err != nil {
   140  		return nil, err
   141  	}
   142  
   143  	return toDuration, nil
   144  }