I was not sure where to post this question but I figured here was better than
anywhere else. I've been working on a datastore client for the Google JSON API
that wraps around the generated Go code here
https://godoc.org/code.google.com/p/google-api-go-client/datastore/v1beta2
My client eases the ability to construct compliant requests, entities, queries
as well as provides some configuration and authentication assistance (much as
the python an java libraries do). However, I ran into a wrinkle during some
testing today. The core of it is how the omitempty tag on the Property struct's
Indexed field is handled. The behavior is displayed in this play link.
What steps will reproduce the problem?
http://play.golang.org/p/4t8ZfyncgA
What is the expected output? What do you see instead?
Here is the output of the play
2009/11/10 23:00:00 A:{BlobValue:Not Omitted Indexed:false}
2009/11/10 23:00:00 Buff {"blobValue":"Not Omitted","indexed":false}
2009/11/10 23:00:00 See how the above has the Indexed property exported?
2009/11/10 23:00:00 Marshal exports it too {"blobValue":"Not
Omitted","indexed":false}
2009/11/10 23:00:00 What happens if we add omitempty to the Indexed property?
2009/11/10 23:00:00 B:{BlobValue:Omitted Indexed:false}
2009/11/10 23:00:00 Buff {"blobValue":"Omitted"}
2009/11/10 23:00:00 See how the above does not have the Indexed property
exported?
2009/11/10 23:00:00 Marshal does not export it either: {"blobValue":"Omitted"}
The issue is that the JSON api itself assumes that indexed = true if you do not
explicitly set it to false in the JSON of your request. This is a problem
because Marshaling the structs in the JSON API library will never give you an
explicit indexed = false even if you have that set to false on the struct
because the Indexed field is tagged 'omitempty'. I was trying to use the
structs from the generated go but I don't see a way to work around this without
just writing/copying my own verbatim copies of those structs so I can change
that single tag. If the indexed field is not in the JSON of the request,
specifically for a BlobValue, and the length of the BlobValue is > 500 bytes
then you will get a 400 error response telling you that it can't save an
indexed blob greater than 500 bytes (which is correct and in the docs). Is
there anything I might be missing?
Here is a cleaned dump of the requests and response
http://pastebin.com/2t2Twy2Q
We have previously been constructing our own JSON for our entities and naively
had the omitempty tag not on our Indexed property. Now that we're trying to
make something that is more flexible we've run into this problem. I'm open to
suggestions. Thank you for your time.
Ross
What version of the product are you using? Google Datastore JSON API v1betav2,
Go 1.3.1
On what operating system? Linux & OSX
Original issue reported on code.google.com by ross.hen...@workiva.com on 6 Nov 2014 at 3:41
Original issue reported on code.google.com by
ross.hen...@workiva.comon 6 Nov 2014 at 3:41