cli.md

Creating dictionary-compressed responses

The response stream formats for compression dictionary transport include a magic file header and a hash of the dictionary. The CLI commands below will create files in the correct format.

dcb

Assuming the dictionary file is dictionary.txt and the file to be compressed is data.text, this will create a dcb-compressed file data.txt.dcb that includes the magic header and embedded dictionary hash:

echo -en '\xffDCB' > data.txt.dcb && \
openssl dgst -sha256 -binary dictionary.txt >> data.txt.dcb && \
brotli --stdout -D dictionary.txt data.txt >> data.txt.dcb

dcz

Assuming the dictionary file is dictionary.txt and the file to be compressed is data.text, this will create a dcz-compressed file data.txt.dcz that includes the magic header and embedded dictionary hash:

echo -en '\x5e\x2a\x4d\x18\x20\x00\x00\x00' > data.txt.dcz && \
openssl dgst -sha256 -binary dictionary.txt >> data.txt.dcz && \
zstd -D dictionary.txt -f -o tmp.zstd data.txt && \
cat tmp.zstd >> data.txt.dcz