Mirroristas/bigchaindb
2
0
Fork 0
mirror of https://github.com/bigchaindb/bigchaindb.git synced 2024-10-13 13:34:05 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #1654 from bigchaindb/docs/1615/explain-fulfillment-uri

Browse Source 
Wrote more about how to calculate a fulfillment string
This commit is contained in:
Troy McConaghy 2017-07-24 16:53:15 +02:00 committed by GitHub
commit 53b15aa723
1 changed files with 14 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
docs/server/source/data-models/inputs-outputs.rst
View File

@ -17,7 +17,7 @@ An input has the following structure:
{
"owners_before": ["<The public_keys list in the output being spent>"],
"fulfillment": "<Fulfillment URI fulfilling the condition of the output being spent>",
"fulfillment": "<String that fulfills the condition in the output being spent>",
"fulfills": {
"output_index": "<Index of the output being spent (an integer)>",
"transaction_id": "<ID of the transaction containing the output being spent>"
@ -28,10 +28,22 @@ You can think of the ``fulfills`` object as a pointer to an output on another tr
A CREATE transaction should have exactly one input. That input can contain one or more ``owners_before``, a ``fulfillment`` (with one signature from each of the owners-before), and the value of ``fulfills`` should be ``null``). A TRANSFER transaction should have at least one input, and the value of ``fulfills`` should not be ``null``.
See the reference on :ref:`inputs <Input>` for more description about the meaning of each field.
To calculate a fulfillment URI, you can use one of the
The ``fulfillment`` string fulfills the condition in the output that is being spent (transferred).
To calculate it:
1. Determine the fulfillment as per the `Crypto-Conditions spec (version 02) <https://tools.ietf.org/html/draft-thomas-crypto-conditions-02>`_.
2. Encode the fulfillment using the `ASN.1 Distinguished Encoding Rules (DER) <http://www.itu.int/ITU-T/recommendations/rec.aspx?rec=12483&lang=en>`_.
3. Encode the resulting bytes using "base64url" (*not* typical base64) as per `RFC 4648, Section 5 <https://tools.ietf.org/html/rfc4648#section-5>`_.
To do those calculations, you can use one of the
:ref:`BigchainDB drivers or transaction-builders <Drivers & Tools>`,
or use a low-level crypto-conditions library as illustrated
in the page about `Handcrafting Transactions <https://docs.bigchaindb.com/projects/py-driver/en/latest/handcraft.html>`_.
A ``fulfillment`` string should look something like:
.. code::
"pGSAIDgbT-nnN57wgI4Cx17gFHv3UB_pIeAzwZCk10rAjs9bgUDxyNnXMl-5PFgSIOrN7br2Tz59MiWe2XY0zlC7LcN52PKhpmdRtcr7GR1PXuTfQ9dE3vGhv7LHn6QqDD6qYHYM"
Outputs