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In PHP, the hash_update_stream() function is a very useful function for step-by-step update of hash values, especially when hashing is required for large data streams. To ensure that the function can work stably and accurately in different scenarios, it is crucial to conduct effective testing. This article will introduce how to effectively test the correctness of the hash_update_stream() function, and comes with an example of an automated test script.
The hash_update_stream() function is a function in PHP used to update hash values, and it is used with hash_init() and hash_final() . This function allows us to perform step-by-step hashing calculations on a data stream (such as a file or other stream resource).
grammar:
hash_update_stream(resource $context, resource $stream, int $length = 8192): bool
$context : hash context, created through hash_init() function.
$stream : An effective stream resource, which can be a file, memory stream, etc.
$length : The maximum number of bytes per read stream, default is 8192 bytes.
The main purpose of testing hash_update_stream() is to ensure its correctness and performance in various situations. This includes:
Ensure that the function can handle input streams of different sizes.
Make sure it performs well in memory usage and performance.
Ensure that the hash value is correctly calculated under different stream content and conditions.
To test hash_update_stream() we can adopt the following strategy:
Basic testing : Test whether the function can update the hash value correctly.
Large file testing : Test the processing capabilities of large files or large data streams.
Boundary testing : For example, test for an empty stream, a very small stream, or a data stream that exceeds the expected size.
Concurrent testing : If necessary, test the stability of the function in concurrent situations.
Below is a simple PHP automated test script example that is used to verify the basic functionality and performance of the hash_update_stream() function.
<?php
// Define a hashing algorithm
$algorithm = 'sha256';
// Test file path（Assume that there is a test file）
$filePath = '/path/to/testfile.txt';
// Initialize hash context
$context = hash_init($algorithm);
// Open the file stream
$stream = fopen($filePath, 'rb');
if (!$stream) {
die('Unable to open the file');
}
// Gradually update the hash value
while (!feof($stream)) {
hash_update_stream($context, $stream, 8192);
}
// Get the final hash value
$hash = hash_final($context);
// Output result
echo "The hash value of the file is: " . $hash . PHP_EOL;
// Close the stream
fclose($stream);
// Automated test examples - Boundary conditions
function testEmptyStream($algorithm) {
$context = hash_init($algorithm);
$stream = fopen('php://memory', 'rb'); // Empty memory stream
hash_update_stream($context, $stream);
$hash = hash_final($context);
echo "The hash value of the empty stream: " . $hash . PHP_EOL;
}
function testLargeStream($algorithm, $filePath) {
$context = hash_init($algorithm);
$stream = fopen($filePath, 'rb');
$startTime = microtime(true);
while (!feof($stream)) {
hash_update_stream($context, $stream, 8192);
}
$hash = hash_final($context);
$endTime = microtime(true);
echo "Hash value of large files: " . $hash . PHP_EOL;
echo "Processing time: " . ($endTime - $startTime) . " Second" . PHP_EOL;
fclose($stream);
}
// Run the test
testEmptyStream($algorithm);
testLargeStream($algorithm, $filePath);
?>
Basic Test :
We first initialize a hash context $context and then gradually update the hash value by opening a file stream $stream . Read 8192 bytes from the file stream and update the hash each time. Finally, hash_final() is used to return the final hash value.
Automated Testing - Boundary Conditions :
The testEmptyStream() function tests the hash value of an empty stream. Create an empty memory stream through php://memory and hash it.
Automated testing - large file processing :
The testLargeStream() function tests the hash calculation of a large file. It calculates processing time by reading a large file and calculating the hash step by step to evaluate the performance of the function.
When performing these tests, you should pay attention to the following aspects:
Consistency of hash values : for the same input stream, hash_update_stream() should always return the same hash value.
Performance : For large files or data streams, functions should be able to process efficiently to avoid memory overflow or long-term blocking.
Boundary conditions : For empty streams, extremely small data streams, etc., the function should be able to handle them correctly and return a valid hash value (such as empty streams return a default hash value).
Through the above tests, you can verify the correctness of the hash_update_stream() function to ensure that it is stable and efficient in actual use. With automated test scripts, we can easily simulate different usage scenarios and conduct more comprehensive testing.
Make sure these tests are performed regularly, especially when updating PHP versions or changing code, can help you quickly catch potential feature issues or performance bottlenecks.
