nulib-spout/openspout3/src/Reader/CSV/RowIterator.php

250 lines
8.3 KiB
PHP

<?php
namespace OpenSpout\Reader\CSV;
use OpenSpout\Common\Entity\Row;
use OpenSpout\Common\Helper\EncodingHelper;
use OpenSpout\Common\Helper\GlobalFunctionsHelper;
use OpenSpout\Common\Manager\OptionsManagerInterface;
use OpenSpout\Reader\Common\Entity\Options;
use OpenSpout\Reader\CSV\Creator\InternalEntityFactory;
use OpenSpout\Reader\RowIteratorInterface;
/**
* Iterate over CSV rows.
*/
class RowIterator implements RowIteratorInterface
{
/**
* Value passed to fgetcsv. 0 means "unlimited" (slightly slower but accomodates for very long lines).
*/
public const MAX_READ_BYTES_PER_LINE = 0;
/** @var null|resource Pointer to the CSV file to read */
protected $filePointer;
/** @var int Number of read rows */
protected $numReadRows = 0;
/** @var null|Row Buffer used to store the current row, while checking if there are more rows to read */
protected $rowBuffer;
/** @var bool Indicates whether all rows have been read */
protected $hasReachedEndOfFile = false;
/** @var string Defines the character used to delimit fields (one character only) */
protected $fieldDelimiter;
/** @var string Defines the character used to enclose fields (one character only) */
protected $fieldEnclosure;
/** @var string Encoding of the CSV file to be read */
protected $encoding;
/** @var bool Whether empty rows should be returned or skipped */
protected $shouldPreserveEmptyRows;
/** @var \OpenSpout\Common\Helper\EncodingHelper Helper to work with different encodings */
protected $encodingHelper;
/** @var \OpenSpout\Reader\CSV\Creator\InternalEntityFactory Factory to create entities */
protected $entityFactory;
/** @var \OpenSpout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
protected $globalFunctionsHelper;
/**
* @param resource $filePointer Pointer to the CSV file to read
*/
public function __construct(
$filePointer,
OptionsManagerInterface $optionsManager,
EncodingHelper $encodingHelper,
InternalEntityFactory $entityFactory,
GlobalFunctionsHelper $globalFunctionsHelper
) {
$this->filePointer = $filePointer;
$this->fieldDelimiter = $optionsManager->getOption(Options::FIELD_DELIMITER);
$this->fieldEnclosure = $optionsManager->getOption(Options::FIELD_ENCLOSURE);
$this->encoding = $optionsManager->getOption(Options::ENCODING);
$this->shouldPreserveEmptyRows = $optionsManager->getOption(Options::SHOULD_PRESERVE_EMPTY_ROWS);
$this->encodingHelper = $encodingHelper;
$this->entityFactory = $entityFactory;
$this->globalFunctionsHelper = $globalFunctionsHelper;
}
/**
* Rewind the Iterator to the first element.
*
* @see http://php.net/manual/en/iterator.rewind.php
*/
#[\ReturnTypeWillChange]
public function rewind(): void
{
$this->rewindAndSkipBom();
$this->numReadRows = 0;
$this->rowBuffer = null;
$this->next();
}
/**
* Checks if current position is valid.
*
* @see http://php.net/manual/en/iterator.valid.php
*/
#[\ReturnTypeWillChange]
public function valid(): bool
{
return $this->filePointer && !$this->hasReachedEndOfFile;
}
/**
* Move forward to next element. Reads data for the next unprocessed row.
*
* @see http://php.net/manual/en/iterator.next.php
*
* @throws \OpenSpout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
*/
#[\ReturnTypeWillChange]
public function next(): void
{
$this->hasReachedEndOfFile = $this->globalFunctionsHelper->feof($this->filePointer);
if (!$this->hasReachedEndOfFile) {
$this->readDataForNextRow();
}
}
/**
* Return the current element from the buffer.
*
* @see http://php.net/manual/en/iterator.current.php
*/
#[\ReturnTypeWillChange]
public function current(): ?Row
{
return $this->rowBuffer;
}
/**
* Return the key of the current element.
*
* @see http://php.net/manual/en/iterator.key.php
*/
#[\ReturnTypeWillChange]
public function key(): int
{
return $this->numReadRows;
}
/**
* Cleans up what was created to iterate over the object.
*/
#[\ReturnTypeWillChange]
public function end(): void
{
// do nothing
}
/**
* This rewinds and skips the BOM if inserted at the beginning of the file
* by moving the file pointer after it, so that it is not read.
*/
protected function rewindAndSkipBom()
{
$byteOffsetToSkipBom = $this->encodingHelper->getBytesOffsetToSkipBOM($this->filePointer, $this->encoding);
// sets the cursor after the BOM (0 means no BOM, so rewind it)
$this->globalFunctionsHelper->fseek($this->filePointer, $byteOffsetToSkipBom);
}
/**
* @throws \OpenSpout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
*/
protected function readDataForNextRow()
{
do {
$rowData = $this->getNextUTF8EncodedRow();
} while ($this->shouldReadNextRow($rowData));
if (false !== $rowData) {
// array_map will replace NULL values by empty strings
$rowDataBufferAsArray = array_map(function ($value) { return (string) $value; }, $rowData);
$this->rowBuffer = $this->entityFactory->createRowFromArray($rowDataBufferAsArray);
++$this->numReadRows;
} else {
// If we reach this point, it means end of file was reached.
// This happens when the last lines are empty lines.
$this->hasReachedEndOfFile = true;
}
}
/**
* @param array|bool $currentRowData
*
* @return bool Whether the data for the current row can be returned or if we need to keep reading
*/
protected function shouldReadNextRow($currentRowData)
{
$hasSuccessfullyFetchedRowData = (false !== $currentRowData);
$hasNowReachedEndOfFile = $this->globalFunctionsHelper->feof($this->filePointer);
$isEmptyLine = $this->isEmptyLine($currentRowData);
return
(!$hasSuccessfullyFetchedRowData && !$hasNowReachedEndOfFile)
|| (!$this->shouldPreserveEmptyRows && $isEmptyLine)
;
}
/**
* Returns the next row, converted if necessary to UTF-8.
* As fgetcsv() does not manage correctly encoding for non UTF-8 data,
* we remove manually whitespace with ltrim or rtrim (depending on the order of the bytes).
*
* @throws \OpenSpout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
*
* @return array|false The row for the current file pointer, encoded in UTF-8 or FALSE if nothing to read
*/
protected function getNextUTF8EncodedRow()
{
$encodedRowData = $this->globalFunctionsHelper->fgetcsv($this->filePointer, self::MAX_READ_BYTES_PER_LINE, $this->fieldDelimiter, $this->fieldEnclosure);
if (false === $encodedRowData) {
return false;
}
foreach ($encodedRowData as $cellIndex => $cellValue) {
switch ($this->encoding) {
case EncodingHelper::ENCODING_UTF16_LE:
case EncodingHelper::ENCODING_UTF32_LE:
// remove whitespace from the beginning of a string as fgetcsv() add extra whitespace when it try to explode non UTF-8 data
$cellValue = ltrim($cellValue);
break;
case EncodingHelper::ENCODING_UTF16_BE:
case EncodingHelper::ENCODING_UTF32_BE:
// remove whitespace from the end of a string as fgetcsv() add extra whitespace when it try to explode non UTF-8 data
$cellValue = rtrim($cellValue);
break;
}
$encodedRowData[$cellIndex] = $this->encodingHelper->attemptConversionToUTF8($cellValue, $this->encoding);
}
return $encodedRowData;
}
/**
* @param array|bool $lineData Array containing the cells value for the line
*
* @return bool Whether the given line is empty
*/
protected function isEmptyLine($lineData)
{
return \is_array($lineData) && 1 === \count($lineData) && null === $lineData[0];
}
}