Implementation method of Chunked encoding in HTTP Response under PHP

The HTTP Response for Chunked encoding transmission will be set in the message header:
Transfer-Encoding: chunked
Indicates that the Content Body will use Chunked encoding to transmit the content.
Chunked encoding is formed by concatenating several Chunks and ends with a chunk indicating a length of 0. Each Chunk is divided into two parts: header and body. The header content specifies the total number of characters (hexadecimal numbers) and quantity unit (generally not written) of the next paragraph of text. The body part is the actual content of the specified length. The two parts Separate them with carriage return and line feed (CRLF). The content in the last Chunk of length 0 is called footer, which is some additional Header information (usually can be ignored directly). The specific Chunk encoding format is as follows:

Copy the code The code is as follows:

　Chunked-Body = *chunk
　　　　"0" CRLF
　　　footer
　　　　CRLF
　chunk = chunk-size [ chunk-ext ] CRLF
　　　 chunk -data CRLF
　hex-no-zero =
　chunk-size = hex-no-zero *HEX
　chunk-ext = *( ";" chunk-ext-name [ "=" chunk-ext-value ] )
　chunk-ext-name = token
　chunk-ext-val = token | quoted-string
　chunk-data = chunk-size(OCTET)
　footer = *entity-header

RFC document The Chunked decoding process in is as follows:

Copy code The code is as follows:

　length := 0
　read chunk-size, chunk-ext (if any) and CRLF
　while (chunk-size > 0) {
　read chunk-data and CRLF
　append chunk-data to entity-body
　length := length + chunk-size
　read chunk-size and CRLF
　}
　read entity-header
　while (entity-header not empty) {
　Append entity-header to existing header fields
　read entity-header
　}
　Content-Length := length
　Remove "chunked" from Transfer-Encoding

Finally provide a PHP version of the chunked decoding code:

Copy Code The code is as follows:

$chunk_size = (integer)hexdec(fgets( $socket_fd, 4096 ) );
while(!feof($socket_fd) && $chunk_size > 0) {
$bodyContent .= fread( $socket_fd, $chunk_size );
fread( $socket_fd, 2 ); // skip rn
$chunk_size = (integer)hexdec(fgets( $socket_fd, 4096 ) );
}

The above introduces the implementation method of Chunked encoding in HTTP Response under PHP, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.