[SteemSQL Wrapper] Added the info about the delay to API

Right now SteemSQL has some issues with performances because of the blockchain size and speed (today Steemit has the biggest number of transactions per day). UPDATE: sorry, it is incorrect, see the arcange's comment.

The result is that SteemSQL sometimes has lagged — for example, right now (when I am writing this post) the delay is 228 minutes. And the lack of information about the delay is a problem for some users.

So I updated SteemSQL Wrapper — now you can get the info about the delay from API.

Example:

curl https://sql.steemhelpers.com/delay
{"delay_seconds": 12018}

The homepage also updated and you can check the delay right on it.

How this works

• Firstly, I get the creation date of the last block from SteemSQL

SELECT TOP 1 timestamp FROM Blocks ORDER BY block_num DESC

• Secondly, I get the creation date of the last block from the blockchain.

blockchain = steem.blockchain.Blockchain()
steemd = steem.steemd.Steemd()
current_block_num = blockchain.get_current_block_num()
current_block = steemd.get_block_header(current_block_num)
blockchain_last_date = datetime.strptime(current_block['timestamp'], "%Y-%m-%dT%H:%M:%S")

• Thirdly, I compare these two dates.

delay = blockchain_last_date - steemsql_last_date

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