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Diffstat (limited to 'src/lib/pgsql/pgsql_exchange.h')
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diff --git a/src/lib/pgsql/pgsql_exchange.h b/src/lib/pgsql/pgsql_exchange.h new file mode 100644 index 0000000..22ec7af --- /dev/null +++ b/src/lib/pgsql/pgsql_exchange.h @@ -0,0 +1,1004 @@ +// Copyright (C) 2016-2022 Internet Systems Consortium, Inc. ("ISC") +// +// This Source Code Form is subject to the terms of the Mozilla Public +// License, v. 2.0. If a copy of the MPL was not distributed with this +// file, You can obtain one at http://mozilla.org/MPL/2.0/. + +#ifndef PGSQL_EXCHANGE_H +#define PGSQL_EXCHANGE_H + +#include <asiolink/io_address.h> +#include <database/database_connection.h> +#include <cc/data.h> +#include <util/triplet.h> +#include <util/boost_time_utils.h> +#include <exceptions/exceptions.h> + +#include <boost/lexical_cast.hpp> +#include <boost/noncopyable.hpp> +#include <boost/shared_ptr.hpp> +#include <libpq-fe.h> + +#include <stdint.h> +#include <vector> +#include <iostream> + +namespace isc { +namespace db { + +/// @brief RAII wrapper for PostgreSQL Result sets +/// +/// When a Postgresql statement is executed, the results are returned +/// in a pointer allocated structure, PGresult*. Data and status information +/// are accessed via calls to functions such as PQgetvalue() which require +/// the results pointer. In order to ensure this structure is freed, any +/// invocation of Psql function which returns a PGresult* (e.g. PQexec, +/// PQExecPrepared, ...) must save the result to an instance of this +/// class. Example: +/// {{{ +/// PgSqlResult r(PQexec(conn_, "ROLLBACK")); +/// }}} +/// +/// This eliminates the need for an explicit release via, PQclear() and +/// guarantees that the resources are released even if the an exception is +/// thrown. + +class PgSqlResult : public boost::noncopyable { +public: + /// @brief Constructor + /// + /// Store the pointer to the fetched result set. Set row and column + /// counts for convenience. + /// + /// @param result pointer to the Postgresql client layer result + /// If the value of is NULL, row and col values will be set to -1. + /// This allows PgSqlResult to be passed into statement error + /// checking. + PgSqlResult(PGresult *result); + + /// @brief Destructor + /// + /// Frees the result set + ~PgSqlResult(); + + /// @brief Returns the number of rows in the result set. + int getRows() const { + return (rows_); + } + + /// @brief Returns the number of columns in the result set. + int getCols() const { + return (cols_); + } + + /// @brief Determines if a row index is valid + /// + /// @param row index to range check + /// + /// @throw DbOperationError if the row index is out of range + void rowCheck(int row) const; + + /// @brief Determines if a column index is valid + /// + /// @param col index to range check + /// + /// @throw DbOperationError if the column index is out of range + void colCheck(int col) const; + + /// @brief Determines if both a row and column index are valid + /// + /// @param row index to range check + /// @param col index to range check + /// + /// @throw DbOperationError if either the row or column index + /// is out of range + void rowColCheck(int row, int col) const; + + /// @brief Fetches the name of the column in a result set + /// + /// Returns the column name of the column from the result set. + /// If the column index is out of range it will return the + /// string "Unknown column:<index>" + /// + /// @param col index of the column name to fetch + /// @return string containing the name of the column + /// This method is exception safe. + std::string getColumnLabel(const int col) const; + + /// @brief Conversion Operator + /// + /// Allows the PgSqlResult object to be passed as the result set argument to + /// PQxxxx functions. + operator PGresult*() const { + return (result_); + } + + /// @brief Boolean Operator + /// + /// Allows testing the PgSqlResult object for emptiness: "if (result)" + operator bool() const { + return (result_); + } + +private: + PGresult* result_; ///< Result set to be freed + int rows_; ///< Number of rows in the result set + int cols_; ///< Number of columns in the result set +}; + +typedef boost::shared_ptr<PgSqlResult> PgSqlResultPtr; + +/// @brief Structure used to bind C++ input values to dynamic SQL parameters +/// The structure contains three vectors which store the input values, +/// data lengths, and formats. These vectors are passed directly into the +/// PostgreSQL execute call. +/// +/// Note that the data values are stored as pointers. These pointers need to +/// be valid for the duration of the PostgreSQL statement execution. In other +/// words populating them with pointers to values that go out of scope before +/// statement is executed is a bad idea. +/// +/// Other than vectors or buffers of binary data, all other values are currently +/// converted to their string representation prior to sending them to PostgreSQL. +/// All of the add() method variants which accept a non-string value internally +/// create the conversion string which is then retained in the bind array to ensure +/// scope. +/// +/// @brief smart pointer to const std::strings used by PsqlBindArray to ensure scope +/// of strings supplying exchange values +typedef boost::shared_ptr<const std::string> ConstStringPtr; + +struct PsqlBindArray { + /// @brief Constructor. + PsqlBindArray() : values_(0), lengths_(0), formats_(0) {} + + /// @brief Vector of pointers to the data values. + std::vector<const char*> values_; + + /// @brief Vector of data lengths for each value. + std::vector<int> lengths_; + + /// @brief Vector of "format" for each value. A value of 0 means the + /// value is text, 1 means the value is binary. + std::vector<int> formats_; + + /// @brief Format value for text data. + static const int TEXT_FMT; + + /// @brief Format value for binary data. + static const int BINARY_FMT; + + /// @brief Constant string passed to DB for boolean true values. + static const char* TRUE_STR; + + /// @brief Constant string passed to DB for boolean false values. + static const char* FALSE_STR; + + /// @brief Fetches the number of entries in the array. + /// @return Returns size_t containing the number of entries. + size_t size() const { + return (values_.size()); + } + + /// @brief Indicates it the array is empty. + /// @return Returns true if there are no entries in the array, false + /// otherwise. + bool empty() const { + return (values_.empty()); + } + + /// @brief Adds a char array to bind array based + /// + /// Adds a TEXT_FMT value to the end of the bind array, using the given + /// char* as the data source. The value is expected to be NULL + /// terminated. The caller is responsible for ensuring that value + /// remains in scope until the bind array has been discarded. + /// + /// @param value char array containing the null-terminated text to add. + /// @throw DbOperationError if value is NULL. + void add(const char* value); + + /// @brief Adds a string value to the bind array + /// + /// Adds a TEXT formatted value to the end of the bind array using the + /// given string as the data source. The caller is responsible for + /// ensuring that string parameter remains in scope until the bind + /// array has been discarded. + /// + /// @param value std::string containing the value to add. + void add(const std::string& value); + + /// @brief Inserts a string value to the bind array before the given index + /// + /// Inserts a TEXT_FMT value into the bind array before the element + /// position given by index, using the given char* as the data source. + /// The value is expected to be NULL terminated. The caller is responsible + /// for ensuring that value remains in scope until the bind array has been + /// discarded. + /// + /// @param value char array containing the null-terminated text to add. + /// @param index element position before which the string should be inserted. + /// + /// @throw DbOperationError if value is NULL. + /// @throw OutOfRange if the index is beyond the end of the array. + void insert(const char* value, size_t index); + + /// @brief Inserts a string value to the bind array before the given index + /// + /// Inserts a TEXT_FMT value into the bind array before the element + /// position given by index, using the given given string as the data + /// source. This creates an internally scoped copy of the string. + /// + /// @param value char array containing the null-terminated text to add. + /// @param index element position before which the string should be + /// inserted. + /// + /// @throw DbOperationError if value is NULL. + /// @throw OutOfRange if the index is beyond the end of the array. + void insert(const std::string& value, size_t index); + + /// @brief Removes the last entry in the bind array. + /// + /// @throw OutOfRange if array is empty. + void popBack(); + + /// @brief Adds a vector of binary data to the bind array. + /// + /// Adds a BINARY_FMT value to the end of the bind array using the + /// given vector as the data source. NOTE this does not replicate + /// the vector, so it must remain in scope until the bind array + /// is destroyed. + /// + /// @param data vector of binary bytes. + void add(const std::vector<uint8_t>& data); + + /// @brief Adds a vector of binary data to the bind array. + /// + /// Adds a BINARY_FMT value to the end of the bind array using the + /// given vector as the data source. This creates an internally scoped + /// copy of the vector. + /// + /// @param data vector of binary bytes. + void addTempBinary(const std::vector<uint8_t>& data); + + /// @brief Adds a buffer of binary data to the bind array. + /// + /// Adds a BINARY_FMT value to the end of the bind array using the + /// given vector as the data source. NOTE this does not replicate + /// the buffer, so it must remain in scope until the bind array + /// is destroyed. + /// + /// @param data buffer of binary data. + /// @param len number of bytes of data in buffer + /// @throw DbOperationError if data is NULL. + void add(const uint8_t* data, const size_t len); + + /// @brief Adds a temporary buffer of binary data to the bind array. + /// + /// Adds a BINARY_FMT value to the end of the bind array using the + /// given vector as the data source. + /// Prior to adding the buffer, it is duplicated as a ConstStringPtr + /// and saved internally. This guarantees the buffer remains in scope + /// until the PsqlBindArray is destroyed, without the caller maintaining + /// the buffer values. + /// + /// @param data buffer of binary data. + /// @param len number of bytes of data in buffer + /// @throw DbOperationError if data is NULL. + void addTempBuffer(const uint8_t* data, const size_t len); + + /// @brief Adds a boolean value to the bind array. + /// + /// Converts the given boolean value to its corresponding to PostgreSQL + /// string value and adds it as a TEXT_FMT value to the bind array. + /// This creates an internally scoped string. + /// + /// @param value the boolean value to add. + void add(const bool& value); + + /// @brief Adds a uint8_t value to the bind array. + /// + /// Converts the given uint8_t value to its corresponding numeric string + /// literal and adds it as a TEXT_FMT value to the bind array. + /// This creates an internally scoped string. + /// + /// @param byte the one byte value to add. + void add(const uint8_t& byte); + + /// @brief Adds the given IOAddress value to the bind array. + /// + /// Converts the IOAddress, based on its protocol family, to the + /// corresponding string literal and adds it as a TEXT_FMT value to + /// the bind array. + /// This creates an internally scoped string. + /// + /// @param addr IP address value to add. + void add(const isc::asiolink::IOAddress& addr); + + /// @brief Adds the given value to the bind array. + /// + /// Converts the given value to its corresponding string literal + /// boost::lexical_cast and adds it as a TEXT_FMT value to the bind array. + /// This is intended primarily for numeric types. + /// This creates an internally scoped string. + /// + /// @param value data value to add. + template<typename T> + void add(const T& value) { + addTempString(boost::lexical_cast<std::string>(value)); + } + + /// @brief Binds the given string to the bind array. + /// + /// Prior to add the given string the vector of exchange values, + /// it duplicated as a ConstStringPtr and saved internally. This guarantees + /// the string remains in scope until the PsqlBindArray is destroyed, + /// without the caller maintaining the string values. + /// + /// @param str string value to add. + void addTempString(const std::string& str); + + /// @brief Adds a NULL value to the bind array + /// + /// This should be used whenever the value for a parameter specified + /// in the SQL statement should be NULL. + void addNull(const int format = PsqlBindArray::TEXT_FMT); + + /// @brief Adds an integer Triplet's value to the bind array + /// + /// Stores the current value of a triplet to the bind array. + /// If it is unspecified it stores a NULL. + /// + /// @param triplet Triplet instance from which to get the value. + void add(const isc::util::Triplet<uint32_t>& triplet); + + /// @brief Adds an integer Triplet's minimum value to the bind array + /// + /// Stores the minimum value of a triplet to the bind array. + /// If it is unspecified it stores a NULL. + /// + /// @param triplet Triplet instance from which to get the value. + void addMin(const isc::util::Triplet<uint32_t>& triplet); + + /// @brief Adds an integer Triplet's maximum value to the bind array + /// + /// Stores the maximum value of a triplet to the bind array. + /// If it is unspecified it stores a NULL. + /// + /// @param triplet Triplet instance from which to get the value. + void addMax(const isc::util::Triplet<uint32_t>& triplet); + + /// @brief Adds an @c Optional string to the bind array. + /// + /// Optional strings require adding a temp string to the + /// bind array, unlike other types which implicitly do so. + /// + /// @param value Optional string value to add + void addOptional(const util::Optional<std::string>& value); + + /// @brief Adds an @c Optional<type> value to the bind array. + /// + /// @tparam T variable type corresponding to the binding type, e.g. + /// @c string, bool, uint8_t, @c uint16_t etc. + /// @param value Optional of type T. + template<typename T> + void addOptional(const util::Optional<T>& value) { + if (value.unspecified()) { + addNull(); + } else { + add(value); + } + } + + /// @brief Adds an IPv4 address to the bind array. + /// + /// This is used for inet type columns. + /// + /// @param value Optional boolean value to add + /// @throw BadValue if the address is not a IPv4 address. + void addInet4(const isc::asiolink::IOAddress& value); + + /// @brief Adds an IPv6 address to the bind array. + /// + /// This is used for inet type columns. + /// + /// @param value Optional boolean value to add + /// @throw BadValue if the address is not a IPv6 address. + void addInet6(const isc::asiolink::IOAddress& value); + + /// @brief Adds an @c Optional IPv4 address to the bind array. + /// + /// This is used for inet type columns. + /// + /// @param value Optional boolean value to add + /// @throw BadValue if the address is not a IPv4 address. + void addOptionalInet4(const util::Optional<isc::asiolink::IOAddress>& value); + + /// @brief Adds an @c Optional IPv6 address to the bind array. + /// + /// This is used for inet type columns which expect + /// v4 addresses to be inserted in string form: + /// '3001::1' + /// + /// @param value Optional boolean value to add + /// @throw BadValue if the address is not a IPv6 address. + void addOptionalInet6(const util::Optional<isc::asiolink::IOAddress>& value); + + + /// @brief Adds a timestamp from a ptime to the bind array. + /// + /// Precision is seconds. + /// + /// @param timestamp Timestamp value to be sent to the database. + /// @throw BadValue if the timestamp exceeds DatabaseConnection::MAX_DB_TIME. + void addTimestamp(const boost::posix_time::ptime& timestamp); + + /// @brief Adds a timestamp of the current time to the bind array. + /// + /// Precision is seconds. + void addTimestamp(); + + /// @brief Adds an ElementPtr to the bind array + /// + /// Adds a TEXT_FMT value to the end of the bind array containing + /// the JSON text output by given ElementPtr::toJSON(). + /// + /// @param value ElementPtr containing Element tree to add. + /// @throw DbOperationError if value is NULL. + void add(const data::ElementPtr& value); + + /// @brief Adds a ConstElementPtr to the bind array + /// + /// Adds a TEXT_FMT value to the end of the bind array containing + /// the JSON text output by given ElementPtr::toJSON(). + /// + /// @param value ElementPtr containing Element tree to add. + /// @throw DbOperationError if value is NULL. + void add(const data::ConstElementPtr& value); + + /// @brief Dumps the contents of the array to a string. + /// @return std::string containing the dump + std::string toText() const; + + // --- the following methods are mostly useful for testing ----- + + /// @brief Determines if specified value is null + /// @param index if array holds more than one value, this index determines + /// which column to use + /// @return true if the column is defined and is null + bool amNull(size_t index = 0) const; + + /// @brief Returns the value as an integer. + /// @param index if array holds more than one value, this index determines + /// which column to use + /// @return value interpreted as specified integer type + /// @throw OutOfRange if the offset is too large + /// @throw BadValue if the data is null + /// @throw boost::bad_lexical_cast if value is not an integer + template<typename T> + T getInteger(size_t index = 0) { + if (values_.size() < index + 1) { + isc_throw(OutOfRange, "Invalid index " << index << ", the values array has " + << values_.size() << " element(s)"); + } + auto x = values_.at(index); + if (!x) { + isc_throw(BadValue, "the data in column " << index << " is null"); + } + return (boost::lexical_cast<T>(x)); + } + + /// @brief Returns the column type + /// @param index if array holds more than one value, this index determines + /// which column to use + /// @return the type of specified column + /// @throw BadValue if the offset is too large + int getType(size_t index = 0 ) { + if (formats_.size() < index + 1) { + isc_throw(OutOfRange, "Invalid index " << index << ", the formats_ array has " + << formats_.size() << " element(s)"); + } + return (formats_.at(index)); + } + +private: + /// @brief vector of strings which supplied the values + std::vector<ConstStringPtr> bound_strs_; +}; + +/// @brief Defines a smart pointer to PsqlBindArray +typedef boost::shared_ptr<PsqlBindArray> PsqlBindArrayPtr; + +/// @brief Base class for marshalling data to and from PostgreSQL. +/// +/// Provides the common functionality to set up binding information between +/// application objects in the program and their representation in the +/// database, and for retrieving column values from rows of a result set. +class PgSqlExchange { +public: + /// @brief Constructor + PgSqlExchange(const size_t num_columns = 0) : columns_(num_columns) {} + + /// @brief Destructor + virtual ~PgSqlExchange() {} + + /// @brief Converts UTC time_t value to a text representation in local time. + /// + /// @param input_time A time_t value representing time. + /// @return std::string containing stringified time. + static std::string convertToDatabaseTime(const time_t input_time); + + /// @brief Converts local time_t value to a text representation in local time. + /// + /// @param input_time A time_t value representing time. + /// @return std::string containing stringified time. + static std::string convertLocalToDatabaseTime(const time_t input_time); + + /// @brief Converts lease expiration time to a text representation in + /// local time. + /// + /// The expiration time is calculated as a sum of the cltt (client last + /// transmit time) and the valid lifetime. + /// + /// The format of the output string is "%Y-%m-%d %H:%M:%S". Database + /// table columns using this value should be typed as TIMESTAMP WITH + /// TIME ZONE. For such columns PostgreSQL assumes input strings without + /// timezones should be treated as in local time and are converted to UTC + /// when stored. Likewise, these columns are automatically adjusted + /// upon retrieval unless fetched via "extract(epoch from <column>))". + /// + /// Unless we start using binary input, timestamp columns must be input as + /// date/time strings. + /// + /// @param cltt Client last transmit time + /// @param valid_lifetime Valid lifetime + /// + /// @return std::string containing the stringified time + /// @throw isc::BadValue if the sum of the calculated expiration time is + /// greater than the value of @c DataSource::MAX_DB_TIME. + static std::string convertToDatabaseTime(const time_t cltt, + const uint32_t valid_lifetime); + + /// @brief Converts time stamp from the database to a time_t + /// + /// We're fetching timestamps as an integer string of seconds since the + /// epoch. This method converts such a string to a time_t. + /// + /// @param db_time_val timestamp to be converted. This value + /// is expected to be the number of seconds since the epoch + /// expressed as base-10 integer string. + /// @return Converted timestamp as time_t value. + static time_t convertFromDatabaseTime(const std::string& db_time_val); + + /// @brief Converts time stamp from the database to a boost::posix::ptime + /// + /// We're fetching timestamps as an integer string of seconds since the + /// epoch. This method converts such a string to a boost::posix_time::ptime. + /// + /// @param db_time_val timestamp to be converted. This value + /// is expected to be the number of seconds since the epoch + /// expressed as base-10 integer string. + /// @param[out] conv_time resulting time as a ptime (UTC) + static void convertFromDatabaseTime(const std::string& db_time_val, + boost::posix_time::ptime& conv_time); + + /// @brief Gets a pointer to the raw column value in a result set row + /// + /// Given a result set, row, and column return a const char* pointer to + /// the data value in the result set. The pointer is valid as long as + /// the result set has not been freed. It may point to text or binary + /// data depending on how query was structured. You should not attempt + /// to free this pointer. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// + /// @return a const char* pointer to the column's raw data + /// @throw DbOperationError if the value cannot be fetched. + static const char* getRawColumnValue(const PgSqlResult& r, const int row, + const size_t col); + + /// @brief Fetches the name of the column in a result set + /// + /// Returns the column name of the column from the result set. + /// If the column index is out of range it will return the + /// string "Unknown column:<index>". Note this is NOT from the + /// list of columns defined in the exchange. + /// + /// @param r the result set containing the query results + /// @param col index of the column name to fetch + /// + /// @return string containing the name of the column + static std::string getColumnLabel(const PgSqlResult& r, const size_t col); + + /// @brief Fetches text column value as a string + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] value parameter to receive the string value + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static void getColumnValue(const PgSqlResult& r, const int row, + const size_t col, std::string& value); + + /// @brief Fetches boolean text ('t' or 'f') as a bool. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] value parameter to receive the converted value + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static void getColumnValue(const PgSqlResult& r, const int row, + const size_t col, bool &value); + + /// @brief Fetches an integer text column as a uint8_t. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] value parameter to receive the converted value + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static void getColumnValue(const PgSqlResult& r, const int row, + const size_t col, uint8_t &value); + + /// @brief Converts a column in a row in a result set into IPv4 address. + /// + /// This is used to fetch values from inet type columns. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// + /// @return isc::asiolink::IOAddress containing the IPv4 address. + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static isc::asiolink::IOAddress getInetValue4(const PgSqlResult& r, + const int row, + const size_t col); + + /// @brief Converts a column in a row in a result set into IPv6 address. + /// + /// This is used to fetch values from inet type columns. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// + /// @return isc::asiolink::IOAddress containing the IPv6 address. + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static isc::asiolink::IOAddress getInetValue6(const PgSqlResult& r, + const int row, + const size_t col); + + /// @brief Converts a column in a row in a result set into IPv6 address. + /// + /// This used for IPv6 columns stored as varchar. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// + /// @return isc::asiolink::IOAddress containing the IPv6 address. + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static isc::asiolink::IOAddress getIPv6Value(const PgSqlResult& r, + const int row, + const size_t col); + + /// @brief Returns true if a column within a row is null + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// + /// @return True if the column values in the row is NULL, false otherwise. + static bool isColumnNull(const PgSqlResult& r, const int row, + const size_t col); + + /// @brief Fetches a text column as the given value type + /// + /// Uses boost::lexicalcast to convert the text column value into + /// a value of type T. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] value parameter to receive the converted value + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + template<typename T> + static void getColumnValue(const PgSqlResult& r, const int row, + const size_t col, T& value) { + const char* data = getRawColumnValue(r, row, col); + try { + value = boost::lexical_cast<T>(data); + } catch (const std::exception& ex) { + isc_throw(db::DbOperationError, "Invalid data:[" << data + << "] for row: " << row << " col: " << col << "," + << getColumnLabel(r, col) << " : " << ex.what()); + } + } + + /// @brief Fetches a timestamp column as a ptime. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] value ptime parameter to receive the converted timestamp + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static void getColumnValue(const PgSqlResult& r, const int row, + const size_t col, boost::posix_time::ptime& value); + + /// @brief Fetches a JSON column as an ElementPtr. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] value ElementPtr to receive the column data + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static void getColumnValue(const PgSqlResult& r, const int row, + const size_t col, data::ElementPtr& value); + + /// @brief Converts a column in a row in a result set to a binary bytes + /// + /// Method is used to convert columns stored as BYTEA into a buffer of + /// binary bytes, (uint8_t). It uses PQunescapeBytea to do the conversion. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] buffer pre-allocated buffer to which the converted bytes + /// will be stored. + /// @param buffer_size size of the output buffer + /// @param[out] bytes_converted number of bytes converted + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static void convertFromBytea(const PgSqlResult& r, const int row, + const size_t col, uint8_t* buffer, + const size_t buffer_size, + size_t &bytes_converted); + + /// @brief Converts a column in a row in a result set to a binary bytes + /// + /// Method is used to convert columns stored as BYTEA into a vector of + /// binary bytes, (uint8_t). It uses PQunescapeBytea to do the conversion. + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row + /// @param[out] value vector to receive the converted bytes + /// value + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static void convertFromBytea(const PgSqlResult& r, const int row, + const size_t col, std::vector<uint8_t>& value); + + /// @brief Fetches a uint32_t value into a Triplet using a single + /// column value + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param col the column number within the row. If the column + /// is null, the Triplet is returned as unspecified. + /// @return Triplet to receive the column value + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static isc::util::Triplet<uint32_t> getTripletValue(const PgSqlResult& r, + const int row, + const size_t col); + + /// @brief Fetches a uint32_t value into a Triplet using a three + /// column values: default, minimum, and maximum + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// @param def_col the column number within the row that contains the + /// default value. If this column is null, the Triplet is returned + /// as unspecified. + /// @param min_col the column number within the row that contains the + /// minimum value. + /// @param max_col the column number within the row that contains the + /// maximum value. + /// @return Triplet to receive the column value + /// + /// @throw DbOperationError if the value cannot be fetched or is + /// invalid. + static isc::util::Triplet<uint32_t> getTripletValue(const PgSqlResult& r, + const int row, + const size_t def_col, + const size_t min_col, + const size_t max_col); + + /// @brief Diagnostic tool which dumps the Result row contents as a string + /// + /// @param r the result set containing the query results + /// @param row the row number within the result set + /// + /// @return A string depiction of the row contents. + static std::string dumpRow(const PgSqlResult& r, int row); + +protected: + /// @brief Stores text labels for columns, currently only used for + /// logging and errors. + std::vector<std::string> columns_; +}; + +/// @brief Convenience class which facilitates fetching column values +/// from a result set row. +class PgSqlResultRowWorker { +public: + /// @brief Constructor + /// + /// @param r result set containing the fetched rows of data. + /// @param row zero-based index of the desired row, (e.g. + /// 0 .. n - 1 where n = number of rows in r) + /// @throw DbOperationError if row value is invalid. + PgSqlResultRowWorker(const PgSqlResult& r, const int row); + + /// @brief Indicates whether or not the given column value is null. + /// + /// @param col the column number within the row + /// + /// @return true if the value is null, false otherwise. + bool isColumnNull(const size_t col); + + /// @brief Fetches the column value as a string. + /// + /// @param col the column number within the row + /// + /// @return std::string containing the column value. + std::string getString(const size_t col); + + /// @brief Fetches the boolean value at the given column. + /// + /// @param col the column number within the row + /// + /// @return bool containing the column value. + bool getBool(const size_t col); + + /// @brief Fetches the floating point value at the given column. + /// + /// @param col the column number within the row + /// + /// @return double containing the column value. + double getDouble(const size_t col); + + /// @brief Gets a pointer to the raw column value in a result set row + /// + /// Given a column return a const char* pointer to the data value in + /// the result set row. The pointer is valid as long as the underlying + /// result set has not been freed. It may point to text or binary + /// data depending on how query was structured. You should not attempt + /// to free this pointer. + /// + /// @param col the column number within the row + /// + /// @return a const char* pointer to the column's raw data + const char* getRawColumnValue(const size_t col); + + /// @brief Fetches the uint64_t value at the given column. + /// + /// @param col the column number within the row + /// + /// @return uint64_t containing the column value + uint64_t getBigInt(const size_t col); + + /// @brief Fetches the uint32_t value at the given column. + /// + /// @param col the column number within the row + /// + /// @return uint32_t containing the column value + uint32_t getInt(const size_t col); + + /// @brief Fetches the uint16_t value at the given column. + /// + /// @param col the column number within the row + /// + /// @return uint16_t containing the column value + uint16_t getSmallInt(const size_t col); + + /// @brief Fetches binary data at the given column into a vector. + /// + /// @param col the column number within the row + /// @param[out] value vector to receive the fetched data. + void getBytes(const size_t col, std::vector<uint8_t>& value); + + /// @brief Fetches the v4 IP address at the given column. + /// + /// This is used to fetch values from inet type columns. + /// @param col the column number within the row + /// + /// @return isc::asiolink::IOAddress containing the IPv4 address. + isc::asiolink::IOAddress getInet4(const size_t col); + + /// @brief Fetches the v6 IP address at the given column. + /// + /// This is used to fetch values from inet type columns. + /// @param col the column number within the row + /// + /// @return isc::asiolink::IOAddress containing the IPv6 address. + isc::asiolink::IOAddress getInet6(const size_t col); + + /// @brief Fetches a text column as the given value type + /// + /// Uses boost::lexicalcast to convert the text column value into + /// a value of type T. + /// + /// @param col the column number within the row + /// @param[out] value parameter to receive the converted value + template<typename T> + void getColumnValue(const size_t col, T& value) { + PgSqlExchange::getColumnValue(r_, row_, col, value); + } + + /// @brief Fetches a timestamp column as a ptime. + /// + /// @param col the column number within the row + /// @return ptime parameter to receive the converted timestamp + boost::posix_time::ptime getTimestamp(const size_t col); + + /// @brief Fetches a JSON column as an ElementPtr. + /// + /// @param col the column number within the row + /// @return ElementPtr parameter to receive the column value + data::ElementPtr getJSON(const size_t col); + + /// @brief Fetches a uint32_t value into a Triplet using a single + /// column value + /// + /// @param col the column number within the row If the column + /// is null, the Triplet is returned as unspecified. + /// @return Triplet to receive the column value + isc::util::Triplet<uint32_t> getTriplet(const size_t col); + + /// @brief Fetches a uint32_t value into a Triplet using a three + /// column values: default, minimum, and maximum + /// + /// @param def_col the column number within the row that contains the + /// default value. If this column is null, the Triplet is returned + /// as unspecified. + /// @param min_col the column number within the row that contains the + /// minimum value. + /// @param max_col the column number within the row that contains the + /// maximum value. + /// @return Triplet to receive the column value + isc::util::Triplet<uint32_t> getTriplet(const size_t def_col, + const size_t min_col, + const size_t max_col); + + /// @brief Diagnostic tool which dumps the Result row contents as a string + /// + /// @return A string representation of the row contents. + std::string dumpRow(); + +private: + /// @brief Result set containing the row. + const PgSqlResult& r_; + + /// @brief Index of the desired row. + size_t row_; +}; + +/// @brief Pointer to a result row worker. +typedef boost::shared_ptr<PgSqlResultRowWorker> PgSqlResultRowWorkerPtr; + +} // end of isc::db namespace +} // end of isc namespace + +#endif // PGSQL_EXCHANGE_H |