Go 1.8 + datastore.RunInTransaction

[aleem....@gmail.com]

I just opted into the go 1.8 beta for appengine standard because a library I am depending on has moved to using the native context.Context.

However, it seems that the appengine datastore package does not support the native context.Context and instead still uses golang.org/x/net/context. 

How do I use the datastore and memcache packages on GAE Go 1.8 standard?

thanks!

[mg...@shift.com]

Since the old and new "Context" interfaces are equivalent you can pass them back and forth interchangeably. Do you have an example that wasn't working for you?

[aleem....@gmail.com]

Here's the error I get when running go build:

./DAO.go:125: cannot use func literal (type func("context".Context) error) as type func("golang.org/x/net/context".Context) error in argument to "google.golang.org/appengine/datastore".RunInTransaction

Here's a subset of my code:

import (

"context"

"google.golang.org/appengine/datastore"

)

func MyFunction(c context.Context, f func(tc context.Context) (bool, error, *Build), opts *datastore.TransactionOptions) error {
        // do some stuff
 err := datastore.RunInTransaction(c, func(tc context.Context) error {

 var innerError error
 didSaveBuild, innerError, build = f(tc)
 return innerError
 }, opts)
       // do more
 return err

}

The bolded line throws the error...

[mg...@shift.com]

When you're passing a function as a parameter, Go requires the function signature to match exactly. RunInTransaction requires a "func(x/net/context.Context)" type, so you need to change the signature of the function you're passing there.

However, you can then pass "tc" as a parameter to functions that expect a "context.Context", since their interfaces are compatible.

[Aleem Mawani]

Thanks for that, I'll give that a shot.

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