implement GET /blocks endpoint

bigchaindb/web/routes.py

@@ -1,6 +1,7 @@
 """ API routes definition """
 from flask_restful import Api
 from bigchaindb.web.views import (
+    blocks,
     info,
     statuses,
     transactions as tx,
@@ -23,6 +24,8 @@ def r(*args, **kwargs):
 
 ROUTES_API_V1 = [
     r('/', info.ApiV1Index),
+    r('blocks/<string:block_id>', blocks.BlockApi),
+    r('blocks/', blocks.BlockListApi),
     r('statuses/', statuses.StatusApi),
     r('transactions/<string:tx_id>', tx.TransactionApi),
     r('transactions', tx.TransactionListApi),

bigchaindb/web/views/blocks.py

@@ -0,0 +1,62 @@
+"""This module provides the blueprint for the blocks API endpoints.
+
+For more information please refer to the documentation on ReadTheDocs:
+ - https://docs.bigchaindb.com/projects/server/en/latest/drivers-clients/
+   http-client-server-api.html
+"""
+from flask import current_app
+from flask_restful import Resource, reqparse
+
+from bigchaindb.web.views.base import make_error
+
+
+class BlockApi(Resource):
+    def get(self, block_id):
+        """API endpoint to get details about a block.
+
+        Args:
+            block_id (str): the id of the block.
+
+        Return:
+            A JSON string containing the data about the block.
+        """
+
+        pool = current_app.config['bigchain_pool']
+
+        with pool() as bigchain:
+            block = bigchain.get_block(block_id=block_id)
+
+        if not block:
+            return make_error(404)
+
+        return block
+
+
+class BlockListApi(Resource):
+    def get(self):
+        """API endpoint to get the related blocks and statuses of a transaction.
+
+        Return:
+            A ``dict`` in the format ``{'block_id': <status>}``, where
+            ``<status>`` is one of "valid", "invalid", "undecided", "backlog".
+            It's possible to return multiple keys of 'block_id'.
+        """
+        parser = reqparse.RequestParser()
+        parser.add_argument('tx_id', type=str)
+
+        args = parser.parse_args(strict=True)
+
+        if sum(arg is not None for arg in args.values()) != 1:
+            return make_error(400, "Provide exactly one query parameter. Choices are: block_id, tx_id")
+
+        pool = current_app.config['bigchain_pool']
+        blocks = None
+
+        with pool() as bigchain:
+            if args['tx_id']:
+                blocks = bigchain.get_blocks_status_containing_tx(args['tx_id'])
+
+        if not blocks:
+            return make_error(404)
+
+        return blocks

tests/web/test_blocks.py

@@ -0,0 +1,104 @@
+import pytest
+
+from bigchaindb.models import Transaction
+
+BLOCKS_ENDPOINT = '/api/v1/blocks/'
+
+
+@pytest.mark.bdb
+@pytest.mark.usefixtures('inputs')
+def test_get_block_endpoint(b, client):
+    tx = Transaction.create([b.me], [([b.me], 1)])
+    tx = tx.sign([b.me_private])
+
+    block = b.create_block([tx])
+    b.write_block(block)
+
+    res = client.get(BLOCKS_ENDPOINT + block.id)
+    assert block.to_dict() == res.json
+    assert res.status_code == 200
+
+
+@pytest.mark.bdb
+@pytest.mark.usefixtures('inputs')
+def test_get_block_returns_404_if_not_found(client):
+    res = client.get(BLOCKS_ENDPOINT + '123')
+    assert res.status_code == 404
+
+    res = client.get(BLOCKS_ENDPOINT + '123/')
+    assert res.status_code == 404
+
+
+@pytest.mark.bdb
+@pytest.mark.usefixtures('inputs')
+def test_get_blocks_by_txid_endpoint(b, client):
+    tx = Transaction.create([b.me], [([b.me], 1)])
+    tx = tx.sign([b.me_private])
+
+    tx2 = Transaction.create([b.me], [([b.me], 10)])
+    tx2 = tx2.sign([b.me_private])
+
+    block_invalid = b.create_block([tx])
+    b.write_block(block_invalid)
+
+    res = client.get(BLOCKS_ENDPOINT + "?tx_id=" + tx.id)
+    # test if block is retrieved as undecided
+    assert res.status_code == 200
+    assert block_invalid.id in res.json
+    assert res.json[block_invalid.id] == b.block_election_status(block_invalid.id, block_invalid.voters)
+    assert res.json[block_invalid.id] == 'undecided'
+    assert len(res.json) == 1
+
+    # vote the block invalid
+    vote = b.vote(block_invalid.id, b.get_last_voted_block().id, False)
+    b.write_vote(vote)
+
+    res = client.get(BLOCKS_ENDPOINT + "?tx_id=" + tx.id)
+    # test if block is retrieved as invalid
+    assert res.status_code == 200
+    assert block_invalid.id in res.json
+    assert res.json[block_invalid.id] == b.block_election_status(block_invalid.id, block_invalid.voters)
+    assert res.json[block_invalid.id] == 'invalid'
+    assert len(res.json) == 1
+
+    # create a new block containing the same tx (and tx2 to avoid block id collision)
+    block_valid = b.create_block([tx, tx2])
+    b.write_block(block_valid)
+
+    res = client.get(BLOCKS_ENDPOINT + "?tx_id=" + tx.id)
+    # test if block is retrieved as undecided
+    assert res.status_code == 200
+    assert block_valid.id in res.json
+    assert res.json[block_valid.id] == b.block_election_status(block_valid.id, block_valid.voters)
+    assert res.json[block_valid.id] == 'undecided'
+    assert len(res.json) == 2
+
+    # vote the block valid
+    vote = b.vote(block_valid.id, block_invalid.id, True)
+    b.write_vote(vote)
+
+    res = client.get(BLOCKS_ENDPOINT + "?tx_id=" + tx.id)
+    # test if block is retrieved as valid
+    assert res.status_code == 200
+    assert block_valid.id in res.json
+    assert res.json[block_valid.id] == b.block_election_status(block_valid.id, block_valid.voters)
+    assert res.json[block_valid.id] == 'valid'
+    assert len(res.json) == 2
+
+
+@pytest.mark.bdb
+def test_get_blocks_by_txid_endpoint_returns_404_if_not_found(client):
+    res = client.get(BLOCKS_ENDPOINT + "?tx_id=123")
+    assert res.status_code == 404
+
+
+@pytest.mark.bdb
+def test_get_blocks_by_txid_endpoint_returns_400_bad_query_params(client):
+    res = client.get(BLOCKS_ENDPOINT)
+    assert res.status_code == 400
+
+    res = client.get(BLOCKS_ENDPOINT + "?ts_id=123")
+    assert res.status_code == 400
+
+    res = client.get(BLOCKS_ENDPOINT + "?tx_id=123&block_id=123")
+    assert res.status_code == 400