Is this a BUG REPORT or FEATURE REQUEST? (choose one):

BUG REPORT

Tendermint version (use tendermint version or git rev-parse --verify HEAD if installed from source):

0.16.0-c8a2bdf7

ABCI app (name for built-in, URL for self-written if it's publicly available):

https://github.com/confio/weave
(mycoind)

Merkleeyes version (use git rev-parse --verify HEAD, skip if you don't use it):

Environment:

• OS (e.g. from /etc/os-release): Ubuntu 16.04.4
• Install tools:
• Others:

What happened:

I add tags to my custom app on DeliverTx, and search for them over rpc.
What I get back looks something like this:

{ height: 10881,
    index: 0,
    tx_result: { data: '', tags: [Array] },
    tx: 'CjcKFAkYgpzi47TwsbYesjCeMRz0lhmdEhSrIOWLIXyj4w9AyAjjt178B4bYURoJCNwLGgRDQVNIqgFqCAESIgogCji5T8tsovBm0v4M7uU0vWHUImYnuFikx+hMH4e1o/4iQgpAwYBknp9DsHdcSxOK3oiDCFD8lEKYglBQHO9d8o4fNKdNL+Rjm5Pt9F+bkwsihQF0XlXqMu/I98J5ndX9nYAiAw==',
    proof: { Index: 0, Total: 0, RootHash: '', Data: null, Proof: [Object] } },

When I sent the tx, I get data like:

{ hash: 'F35768030D7051CC8AE7329F807AA7F6CBFACF05',
  height: 22238 }

What you expected to happen:

If the tx_hash is supposed to be the canonical id, it would be nice to return it on /search_tx.
Of course, I can hash it myself, but assumes I have the same hashing algorithm as tendermint,
and makes external (non-golang) libraries harder to develop.

How to reproduce it (as minimally and precisely as possible):

You can work through the demo on https://github.com/confio/weave-js/blob/master/README.md

The error is in the last section "Searching and subscribing to tx", of course, you need to run the server locally and create a few tx first....

Anything else do we need to know:

I showed it to @melekes personally and he agreed it was sub-optimal behavior.