Last week you may remember Twitter planned to enable the new Status ID
generator - 'Snowflake' but didn't. The purpose of this email is to explain
the reason why this didn't happen, what we are doing about it, and what the
new release plan is.
So what is Snowflake?
------------------------------
Snowflake is a service we will be using to generate unique Tweet IDs. These
Tweet IDs are unique 64bit unsigned integers, which, instead of being
sequential like the current IDs, are based on time. The full ID is composed
of a timestamp, a worker number, and a sequence number.
The problem
-----------------
Before launch it came to our attention that some programming languages such
as Javascript cannot support numbers with >53bits. This can be easily
examined by running a command similar to: (90071992547409921).toString() in
your browsers console or by running the following JSON snippet through your
JSON parser.
{"id": 10765432100123456789, "id_str": "10765432100123456789"}
In affected JSON parsers the ID will not be converted successfully and will
lose accuracy. In some parsers there may even be an exception.
The solution
----------------
To allow javascript and JSON parsers to read the IDs we need to include a
string version of any ID when responding in the JSON format. What this means
is Status, User, Direct Message and Saved Search IDs in the Twitter API will
now be returned as an integer and a string in JSON responses. This will
apply to the main Twitter API, the Streaming API and the Search API.
For example, a status object will now contain an id and an id_str. The
following JSON representation of a status object shows the two versions of
the ID fields for each data point.
[
{
"coordinates": null,
"truncated": false,
"created_at": "Thu Oct 14 22:20:15 +0000 2010",
"favorited": false,
"entities": {
"urls": [
],
"hashtags": [
],
"user_mentions": [
{
"name": "Matt Harris",
"id": 777925,
"id_str": "777925",
"indices": [
0,
14
],
"screen_name": "themattharris"
}
]
},
"text": "@themattharris hey how are things?",
"annotations": null,
"contributors": [
{
"id": 819797,
"id_str": "819797",
"screen_name": "episod"
}
],
"id": 12738165059,
"id_str": "12738165059",
"retweet_count": 0,
"geo": null,
"retweeted": false,
"in_reply_to_user_id": 777925,
"in_reply_to_user_id_str": "777925",
"in_reply_to_screen_name": "themattharris",
"user": {
"id": 6253282
"id_str": "6253282"
},
"source": "web",
"place": null,
"in_reply_to_status_id": 12738040524
"in_reply_to_status_id_str": "12738040524"
}
]
What should you do - RIGHT NOW
----------------------------------------------
The first thing you should do is attempt to decode the JSON snippet above
using your production code parser. Observe the output to confirm the ID has
not lost accuracy.
What you do next depends on what happens:
* If your code converts the ID successfully without losing accuracy you are
OK but should consider converting to the _str versions of IDs as soon as
possible.
* If your code has lost accuracy, convert your code to using the _str
version immediately. If you do not do this your code will be unable to
interact with the Twitter API reliably.
* In some language parsers, the JSON may throw an exception when reading the
ID value. If this happens in your parser you will need to ‘pre-parse’ the
data, removing or replacing ID parameters with their _str versions.
Summary
-------------
1) If you develop in Javascript, know that you will have to update your code
to read the string version instead of the integer version.
2) If you use a JSON decoder, validate that the example JSON, above, decodes
without throwing exceptions. If exceptions are thrown, you will need to
pre-parse the data. Please let us know the name, version, and language of
the parser which throws the exception so we can investigate.
Timeline
-----------
by 22nd October 2010 (Friday): String versions of ID numbers will start
appearing in the API responses
4th November 2010 (Thursday) : Snowflake will be turned on but at ~41bit
length
26th November 2010 (Friday) : Status IDs will break 53bits in length and
cease being usable as Integers in Javascript based languages
We understand this isn’t as seamless a transition as we had planned and
appreciate for some of you this change requires an update to your code.
We’ve tried to give as much time as possible for you to make the migration
and update your code to use the new string representations.
Our own products and tools are affected by the change and we will be making
available any pre-parsing snippets we have created to ensure code continues
to work with the new IDs.
Thanks for your support and understanding.
---
@themattharris
Developer Advocate, Twitterhttp://twitter.com/themattharris
