Decode/encode Postgres bytea strings to Buffers
npm install postgres-bytea
To decode a bytea string into a buffer:
const bytea = require('postgres-bytea')
// bytea hex format
bytea.decode('\\x1234') // <Buffer 12 34>
// bytea escape format
bytea.decode('\\000\\100\\200') // <Buffer 00 40 80>
The decode
function supports both the hex format used in Postgres 9+ and the escape format used in Postgres 8 and earlier. It automatically detects the format from the incoming data.
For backward compatibility, decode
is also the default export from the package.
To decode a bytea hex stream into binary:
const bytea = require('postgres-bytea')
readable.pipe(new bytea.Decoder())
Decoder
expects a double-escaped \\x
prefix to allow reading from a COPY TO
statement.
const bytea = require('postgres-bytea')
readable.pipe(new bytea.Encoder())
Encoder
adds a double-escaped \\x
prefix to allow writing to a COPY FROM
statement.
Required
Type: string
A Postgres bytea binary string.
Creates a bytea decoder stream that emits buffer chunks.
Creates a bytea encoder stream that receives buffer chunks and emits them as bytea strings.
The “hex” format encodes binary data as 2 hexadecimal digits per byte, most significant nibble first. The entire string is preceded by the sequence \x (to distinguish it from the escape format). In some contexts, the initial backslash may need to be escaped by doubling it (see Section 4.1.2.1).
https://www.postgresql.org/docs/12/datatype-binary.html#id-1.5.7.12.9
A SELECT
statement returns bytea values using the single-escaped \x
prefix. The COPY TO
and COPY FROM
commands expect and return bytea values with the double-escaped \\x
prefix.
bytea.decode
expects the single-escaped prefix. The Decoder
and Encoder
streams expect the double-escaped prefix, since they are most useful in COPY FROM
and COPY TO
statements.
MIT © Ben Drucker