Javascript implementation of the SSB binary field encodings spec.
The spec only has one type of nil, but JavaScript has two: null and
undefined. ssb-bfe will treat these two values in a way that mirrors what
JSON.stringify does:
null field becomes an object with the
nil marker
JSON.stringify({a: null}) === '{"a": null}'null element becomes an array with the
nil marker
JSON.stringify([null]) === '[null]'undefined field will omit that field
JSON.stringify({a: undefined}) === '{}'undefined element becomes an array with
the nil marker
JSON.stringify([undefined]) === '[null]'encode(input)Takes any JavaScript primitive and returns its encoded counterpart. Is applied recursively in case the input is an object or an array. All inputs are converted to TFD Buffers, except for objects, arrays, and numbers, which remain the same.
decode(input)Takes an encoded value (such as the output from encode) and returns the
decoded counterparts as JavaScript primitives.
decodeTypeFormat(input, typeName, formatName)Takes an encoded value (such as the output from encode), a typeName
and formatName and returns the decoded counterparts as JavaScript
primitives. This is much faster than decode if you know the type.
bfeTypesReturns the bfe.json object that can be used to look up information
based on Type and Field. Example:
const { bfeTypes } = require('ssb-bfe')
const classic_key_size = bfeTypes[0][0].data_lengthbfeNamedTypesReturns the bfe.json object converted to a map where the keys are
the type and format names. Example:
const { bfeNamedTypes } = require('ssb-bfe')
const FEED = bfeNamedTypes['feed']
const CLASSIC_FEED_TF = Buffer.from([FEED.code, FEED.formats['classic'].code])toTF(typeName, formatName)Sometimes when you're wanting to check what sort of buffer you're handling, you want to pivot on the type and format bytes.
const CLASSIC_MSG_TF = Buffer.from([1, 0]) // << Did I get the right codes?
if (buf.slice(0, 2).equals(CLASSIC_MSG_TF)) {
// ...
}because remembering those codes is tricky, it's safer to use this convenience method:
const CLASSIC_MSG_TF = bfe.toTF('msg', 'classic')If you remembered the type or format name wrong, you'll instantly get an error!
Given any input, these functions tell you whether the input is of the specified type (and format, if applicable). Example:
const bfe = require('ssb-bfe')
const x = bfe.encode('@6CAxOI3f+LUOVrbAl0IemqiS7ATpQvr9Mdw9LC4+Uv0=.ed25519')
bfe.isEncodedFeedClassic(x) // trueList of functions:
isEncodedFeed(input) => booleanisEncodedFeedClassic(input) => booleanisEncodedFeedGabbygroveV1(input) => booleanisEncodedFeedBamboo(input) => booleanisEncodedFeedBendybuttV1(input) => booleanisEncodedFeedButtwooV1(input) => booleanisEncodedMessage(input) => booleanisEncodedMessageClassic(input) => booleanisEncodedMessageGabbygroveV1(input) => booleanisEncodedMessageCloaked(input) => booleanisEncodedMessageBamboo(input) => booleanisEncodedMessageBendybuttV1(input) => booleanisEncodedMessageButtwooV1(input) => booleanisEncodedBlob(input) => booleanisEncodedBlobClassic(input) => booleanisEncodedEncryptionKey(input) => booleanisEncodedEncryptionKeyBox2DmDh(input) => booleanisEncodedEncryptionKeyBox2PoboxDh(input) => booleanisEncodedSignature(input) => booleanisEncodedSignatureMsgEd25519(input) => booleanisEncodedEncrypted(input) => booleanisEncodedEncryptedBox1(input) => booleanisEncodedEncryptedBox2(input) => booleanisEncodedGeneric(input) => booleanisEncodedGenericStringUTF8(input) => booleanisEncodedGenericBoolean(input) => booleanisEncodedGenericNil(input) => booleanisEncodedGenericAnyBytes(input) => booleanisEncodedIdentity(input) => booleanisEncodedIdentityPoBox(input) => boolean