Golang KeyRange.StartKey方法代碼示例

// Get a list of all members which are currently in the trash.
func (m *MembershipDB) EnumerateTrashedMembers(prev string, num int32) ([]*MemberWithKey, error) {
	var cp *cassandra.ColumnParent = cassandra.NewColumnParent()
	var pred *cassandra.SlicePredicate = cassandra.NewSlicePredicate()
	var r *cassandra.KeyRange = cassandra.NewKeyRange()
	var kss []*cassandra.KeySlice
	var ks *cassandra.KeySlice
	var rv []*MemberWithKey
	var err error

	// Fetch the protobuf column of the application column family.
	cp.ColumnFamily = "membership_archive"
	pred.ColumnNames = [][]byte{
		[]byte("pb_data"),
	}
	if len(prev) > 0 {
		var uuid cassandra.UUID
		if uuid, err = cassandra.ParseUUID(prev); err != nil {
			return rv, err
		}
		r.StartKey = append([]byte(archivePrefix), []byte(uuid)...)
	} else {
		r.StartKey = []byte(archivePrefix)
	}
	r.EndKey = []byte(archiveEnd)
	r.Count = num

	kss, err = m.conn.GetRangeSlices(cp, pred, r, cassandra.ConsistencyLevel_ONE)
	if err != nil {
		return rv, err
	}

	for _, ks = range kss {
		var member *MemberWithKey
		var scol *cassandra.ColumnOrSuperColumn
		var uuid cassandra.UUID = cassandra.UUIDFromBytes(
			ks.Key[len(archivePrefix):])

		if len(ks.Columns) == 0 {
			continue
		}

		for _, scol = range ks.Columns {
			var col *cassandra.Column = scol.Column

			if string(col.Name) == "pb_data" {
				var agreement = new(MembershipAgreement)
				member = new(MemberWithKey)
				err = proto.Unmarshal(col.Value, agreement)
				proto.Merge(&member.Member, agreement.GetMemberData())
				member.Key = uuid.String()
			}
		}

		if member != nil {
			rv = append(rv, member)
		}
	}

	return rv, nil
}

// Retrieve a specific members detailed membership data, but fetch it by the
// user name of the member.
func (m *MembershipDB) GetMemberDetailByUsername(username string) (
	*MembershipAgreement, error) {
	var member *MembershipAgreement = new(MembershipAgreement)
	var cp *cassandra.ColumnParent = cassandra.NewColumnParent()
	var pred *cassandra.SlicePredicate = cassandra.NewSlicePredicate()
	var kr *cassandra.KeyRange = cassandra.NewKeyRange()
	var expr *cassandra.IndexExpression = cassandra.NewIndexExpression()

	var r []*cassandra.KeySlice
	var ks *cassandra.KeySlice
	var err error

	expr.ColumnName = []byte("username")
	expr.Op = cassandra.IndexOperator_EQ
	expr.Value = []byte(username)

	cp.ColumnFamily = "members"
	pred.ColumnNames = [][]byte{[]byte("pb_data")}
	kr.StartKey = []byte(memberPrefix)
	kr.EndKey = []byte(memberEnd)
	kr.RowFilter = []*cassandra.IndexExpression{expr}

	r, err = m.conn.GetRangeSlices(
		cp, pred, kr, cassandra.ConsistencyLevel_ONE)
	if err != nil {
		return nil, err
	}

	for _, ks = range r {
		var cos *cassandra.ColumnOrSuperColumn

		for _, cos = range ks.Columns {
			var col = cos.Column
			if string(col.Name) == "pb_data" {
				member = new(MembershipAgreement)
				err = proto.Unmarshal(col.Value, member)
				return member, nil
			} else {
				return nil, errors.New("Unexpected column " +
					string(col.Name))
			}
		}
	}

	return nil, errors.New("Not found")
}

func (self *ProductSearchAPI) ServeHTTP(w http.ResponseWriter, req *http.Request) {
	var err error
	var query string = req.FormValue("q")
	var rawdata []byte
	var res CategorizedSearchResult

	numRequests.Add(1)
	numAPIRequests.Add(1)

	// Check the user is in the reqeuested scope.
	if !self.authenticator.IsAuthenticatedScope(req, self.scope) {
		numDisallowedScope.Add(1)
		http.Error(w,
			"You are not in the right group to access this resource",
			http.StatusForbidden)
		return
	}

	if len(query) >= 3 {
		var product_results [][]byte
		var cp *cassandra.ColumnParent = cassandra.NewColumnParent()
		var pred *cassandra.SlicePredicate = cassandra.NewSlicePredicate()
		var kr *cassandra.KeyRange = cassandra.NewKeyRange()
		var colmap map[string][]*cassandra.ColumnOrSuperColumn
		var slices []*cassandra.KeySlice
		var ire *cassandra.InvalidRequestException
		var ue *cassandra.UnavailableException
		var te *cassandra.TimedOutException
		var endkey []byte = []byte(query)
		var r *SearchResult
		var pos int = len(endkey) - 1

		// Handle overflows
		for endkey[pos] == 255 && pos > 0 {
			endkey[pos] = 0
			pos--
		}

		// Produce endkey by incrementing the last byte of the start key.
		endkey[pos]++

		// Search for projects with the given name.
		cp.ColumnFamily = "products_byname"
		pred.ColumnNames = [][]byte{[]byte("product")}

		kr.StartKey = []byte(query)
		kr.EndKey = endkey
		kr.Count = 32 // Limit to 32 results.

		slices, ire, ue, te, err = self.client.GetRangeSlices(
			cp, pred, kr, cassandra.ConsistencyLevel_ONE)
		if ire != nil {
			log.Print("Error fetching products_byname: ", ire.Why)
			numCassandraErrors.Add("invalid-request", 1)
			http.Error(w, ire.Why, http.StatusInternalServerError)
			return
		}
		if ue != nil {
			log.Print("Cassandra unavailable when fetching products_byname")
			numCassandraErrors.Add("invalid-request", 1)
			http.Error(w, "Database unavailable", http.StatusInternalServerError)
			return
		}
		if te != nil {
			log.Print("Cassandra timed out when fetching products_byname")
			numCassandraErrors.Add("timeout", 1)
			http.Error(w, "Database timed out", http.StatusInternalServerError)
			return
		}
		if err != nil {
			log.Print("OS error when fetching products_byname: ", err)
			numCassandraErrors.Add("generic-error", 1)
			http.Error(w, "OS error talking to database",
				http.StatusInternalServerError)
			return
		}

		for _, slice := range slices {
			for _, csc := range slice.Columns {
				var col *cassandra.Column = csc.Column
				if col == nil || !col.IsSetValue() {
					continue
				}

				if string(col.Name) != "product" {
					log.Print("Bizarre products_byname row ",
						string(slice.Key), " (", slice.Key, "), has ",
						string(col.Name), " (", col.Name, ")")
					continue
				}

				r = new(SearchResult)
				r.Name = string(slice.Key)
				r.Uuid = UUID(col.Value).String()
				res.Products = append(res.Products, r)
			}
		}

		// Search for projects with the given name.
		cp.ColumnFamily = "products_bybarcode"
//.........這裏部分代碼省略.........

//.........這裏部分代碼省略.........
			var uid string

			for _, uid = range entry.GetAttributeValues("uidNumber") {
				var uidNumber uint64
				uidNumber, err = strconv.ParseUint(uid, 10, 64)
				if err != nil {
					log.Print("Error parsing \"", uid, "\" as a number: ",
						err)
				} else if uidNumber > greatestUid {
					greatestUid = uidNumber
				}
			}
		}
	}

	// Connect to Cassandra so we can get a list of records to be processed.
	db, err = cassandra.NewRetryCassandraClient(
		config.DatabaseConfig.GetDatabaseServer())
	if err != nil {
		log.Fatal("Error connecting to Cassandra database at ",
			config.DatabaseConfig.GetDatabaseServer(), ": ", err)
	}

	err = db.SetKeyspace(config.DatabaseConfig.GetDatabaseName())
	if err != nil {
		log.Fatal("Error setting keyspace: ", err)
	}

	cp = cassandra.NewColumnParent()
	cp.ColumnFamily = "membership_queue"
	pred = cassandra.NewSlicePredicate()
	pred.ColumnNames = [][]byte{[]byte("pb_data")}
	kr = cassandra.NewKeyRange()
	kr.StartKey = []byte("queue:")
	kr.EndKey = []byte("queue;")

	kss, err = db.GetRangeSlices(cp, pred, kr,
		cassandra.ConsistencyLevel_QUORUM)
	if err != nil {
		log.Fatal("Error getting range slice: ", err)
	}

	for _, ks = range kss {
		mmap = make(map[string]map[string][]*cassandra.Mutation)
		var csc *cassandra.ColumnOrSuperColumn
		for _, csc = range ks.Columns {
			var col *cassandra.Column = csc.Column
			var agreement membersys.MembershipAgreement
			var m *cassandra.Mutation

			if col == nil {
				continue
			}

			if string(col.Name) != "pb_data" {
				log.Print("Column selected was not as requested: ",
					col.Name)
				continue
			}

			err = proto.Unmarshal(col.Value, &agreement)
			if err != nil {
				log.Print("Unable to parse column ", col.Name, " of ",
					ks.Key, ": ", err)
				continue
			}

// Get a list of all membership applications currently in the database.
// Returns a set of "num" entries beginning after "prev". If "criterion" is
// given, it will be compared against the name of the member.
func (m *MembershipDB) EnumerateMembershipRequests(criterion, prev string, num int32) (
	[]*MemberWithKey, error) {
	var cp *cassandra.ColumnParent = cassandra.NewColumnParent()
	var pred *cassandra.SlicePredicate = cassandra.NewSlicePredicate()
	var r *cassandra.KeyRange = cassandra.NewKeyRange()
	var kss []*cassandra.KeySlice
	var ks *cassandra.KeySlice
	var rv []*MemberWithKey
	var err error

	// Fetch the name, street, city and fee columns of the application column family.
	cp.ColumnFamily = "application"
	pred.ColumnNames = [][]byte{
		[]byte("name"), []byte("street"), []byte("city"), []byte("fee"),
		[]byte("fee_yearly"),
	}
	if len(prev) > 0 {
		var uuid cassandra.UUID
		if uuid, err = cassandra.ParseUUID(prev); err != nil {
			return rv, err
		}
		r.StartKey = append([]byte(applicationPrefix), []byte(uuid)...)
	} else {
		r.StartKey = []byte(applicationPrefix)
	}
	r.EndKey = []byte(applicationEnd)
	r.Count = num

	kss, err = m.conn.GetRangeSlices(
		cp, pred, r, cassandra.ConsistencyLevel_ONE)
	if err != nil {
		return rv, err
	}

	for _, ks = range kss {
		var member *MemberWithKey = new(MemberWithKey)
		var scol *cassandra.ColumnOrSuperColumn
		var uuid cassandra.UUID = cassandra.UUIDFromBytes(
			ks.Key[len(applicationPrefix):])

		member.Key = uuid.String()

		if len(ks.Columns) == 0 {
			continue
		}

		for _, scol = range ks.Columns {
			var col *cassandra.Column = scol.Column

			if string(col.Name) == "name" {
				member.Name = proto.String(string(col.Value))
			} else if string(col.Name) == "street" {
				member.Street = proto.String(string(col.Value))
			} else if string(col.Name) == "city" {
				member.City = proto.String(string(col.Value))
			} else if string(col.Name) == "fee" {
				member.Fee = proto.Uint64(binary.BigEndian.Uint64(col.Value))
			} else if string(col.Name) == "fee_yearly" {
				member.FeeYearly = proto.Bool(col.Value[0] == 1)
			}
		}

		rv = append(rv, member)
	}

	return rv, nil
}

// Get a list of all members currently in the database. Returns a set of
// "num" entries beginning after "prev".
// Returns a filled-out member structure and the timestamp when the
// membership was approved.
func (m *MembershipDB) EnumerateMembers(prev string, num int32) (
	[]*Member, error) {
	var cp *cassandra.ColumnParent = cassandra.NewColumnParent()
	var pred *cassandra.SlicePredicate = cassandra.NewSlicePredicate()
	var r *cassandra.KeyRange = cassandra.NewKeyRange()
	var kss []*cassandra.KeySlice
	var ks *cassandra.KeySlice
	var rv []*Member
	var err error

	// Fetch all relevant non-protobuf columns of the members column family.
	cp.ColumnFamily = "members"
	pred.ColumnNames = [][]byte{
		[]byte("name"), []byte("street"), []byte("city"), []byte("country"),
		[]byte("email"), []byte("phone"), []byte("username"), []byte("fee"),
		[]byte("fee_yearly"),
	}
	r.StartKey = []byte(memberPrefix + prev)
	r.EndKey = []byte(memberEnd)
	r.Count = num

	kss, err = m.conn.GetRangeSlices(
		cp, pred, r, cassandra.ConsistencyLevel_ONE)
	if err != nil {
		return rv, err
	}

	for _, ks = range kss {
		var member *Member = new(Member)
		var scol *cassandra.ColumnOrSuperColumn

		if len(ks.Columns) == 0 {
			continue
		}

		member.Email = proto.String(string(ks.Key[len(memberPrefix):]))

		for _, scol = range ks.Columns {
			var col *cassandra.Column = scol.Column
			var colname string = string(col.Name)

			if colname == "name" {
				member.Name = proto.String(string(col.Value))
			} else if colname == "street" {
				member.Street = proto.String(string(col.Value))
			} else if colname == "city" {
				member.City = proto.String(string(col.Value))
			} else if colname == "country" {
				member.Country = proto.String(string(col.Value))
			} else if colname == "email" {
				member.Email = proto.String(string(col.Value))
			} else if colname == "phone" {
				member.Phone = proto.String(string(col.Value))
			} else if colname == "username" {
				member.Username = proto.String(string(col.Value))
			} else if colname == "fee" {
				member.Fee = proto.Uint64(binary.BigEndian.Uint64(col.Value))
			} else if colname == "fee_yearly" {
				member.FeeYearly = proto.Bool(col.Value[0] == 1)
			}
		}

		rv = append(rv, member)
	}

	return rv, nil
}