A presentation at Go Atlanta Meetup in in Atlanta, GA, USA by Kat Cosgrove
A Recipe for Migrating to Go Modules
Modules are the Default …and migrating is easier than you think!
Mender.io ◂ Used for large-scale IoT deployments ◂ Build as a collection of microservices ◂ Varying version tags between services @Dixie3Flatline jfrog.com/shownotes @jfrog 3
Get a go.mod file go mod init ◂ ◂ ◂ ◂ ◂
Glide Godeps Govendor Dep … and more!
v2+ ◂ ◂ ◂ ◂
Slightly more complex Increment major version Add to module path Causes some other issues to address
`go mod init github.com/mendersoftware/deviceauth/v3’ @Dixie3Flatline
jfrog.com/shownotes
@jfrog
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Update imports ◂ ◂ ◂ ◂ @Dixie3Flatline Build and test Both will likely fail Update import statements for new path May want to use a script for this in large projects jfrog.com/shownotes @jfrog 5
Module Versioning ◂ After go mod init or go mod tidy, check version numbers ◂ Some dependencies may cause problems here ◂ Untagged changes in satori/go.uuid broke Mender ◂ At this point, you should be able to build and run tests @Dixie3Flatline
jfrog.com/shownotes
@jfrog
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Module Proxy ◂ ◂ ◂ ◂
JFrog GoCenter Immutable and persistent modules Much faster than cloning Consistent, secure, reproducible builds export GOPROXY=https://gocenter.io
@Dixie3Flatline
jfrog.com/shownotes
@jfrog
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Static Analysis and Code Generators ◂ Some projects may need to handle additional issues with paths here ◂ Remember to look at your .proto and Dockerfiles @Dixie3Flatline jfrog.com/shownotes @jfrog 8
Testing Changes ◂ Go v1.13 made changes to testing ◂ Specifically, when flags are parsed ◂ Move flag.Parse() to main test function @Dixie3Flatline jfrog.com/shownotes @jfrog 9
Thanks! Any questions? You can find me at ◂ ◂ ◂ @Dixie3Flatline katc@jfrog.com jfrog.com/shownotes 10
Modules arrived with Go v1.11, and with Go v1.13, they’re enabled by default. But fear not, updating an established project to support modules doesn’t have to be difficult; you just need to show up armed and aware of a few common problems. To find out just how much trouble this would be, I decided to update a large project myself – the server-side microservices for Mender. In this talk, I’ll share what I learned in doing this and show you how to do the same to your own projects with as little pain as possible.
for free. You
can too.