Managing dependencies
At the build stage, Cloud Functions automatically installs dependencies necessary for a function to run. This is done when creating a new function version.
Cloud Functions supports two ways to automatically manage dependencies: using modules and the dep utility.
mod
Modules are built-in dependency management mechanisms for the Go programming language. This is the main and recommended way to manage dependencies in Cloud Functions.
To install dependencies using modules, import the go.mod file together with the function source code. This installs the latest versions of the packages specified in this file. To explicitly specify the versions, you should also import the go.sum file.
dep
Dep is the dependency management system for Go.
To install dependencies using the dep utility, import the Gopkg.toml and Gopkg.lock files together with the function source code. In this case, the dep ensure command is run just before the code is built.
Note
If you have both the go.mod and Gopkg.toml files, builder performance isn't guaranteed. We don't recommend using these two files at the same time.
The process of installing dependencies has resource and execution time limits. For more information, see Quotas and limits. You can view the dependency installation log using the link that appears in the list of operations.