I'm new to go modules, and am taking them for a spin in a new project which I'm trying to model after the structure described here
Here is an example of my directory structure:
.
├── cmd
│ └── app_name
│ └── main.go
├── go.mod
├── go.sum
├── internal
│ └── bot
│ └── bot.go
└── pkg
├── website_name
│ ├── client.go
│ ├── client.options.go
│ ├── server.go
│ └── server.options.go
└── lib
└── lib.go
Is this idiomatically correct? I know there's not a whole lot of consensus out there, but I'd like to follow best practices.
When I run go build I get 'unexpected module path "github.com/ragurney/app_name/cmd/app_name"', but when I run go build ./... it works. Why?
When I move main.go to the top level everything works as expected. Should I just not use the /cmd pattern with modules?
To answer your first question, its completely opinionated and whatever you like best that is also easy to understand for others you should go with (I think it's fine).
To answer your second question the reason go build ./... works as opposed to go build from the root directory is because ./... starts in the current directory (the root) and searches for all program entry-points and builds them. When you move main.go to the root directory, with this new information, go build working then makes sense, as its only looking in the current directory.
You can explicitly say go build ./cmd/app_name which would also work.
Your application structure works perfectly fine with modules, as I use something very similar to it (https://www.ardanlabs.com/blog/2017/02/package-oriented-design.html) and modules work very well for me.
from what i can tell there is nothing wrong with your project structure. What has worked for me is to run the go build/run command from the project root
eg.
go run github.com/username/project/cmd/somecommand
go build -o somebinary github.com/username/project/cmd/somecommand
I prefer to add the specific file to build, there are some projects with more than one executable
go build -o app ./cmd/server/main.go
Related
I'm using Gradle with the wrapper, and the folder structure by default is like so:
.
├── settings.gradle
├── build.gradle
├── gradle.properties
├── gradle
│ └── wrapper
│ ├── gradle-wrapper.jar
│ └── gradle-wrapper.properties
├── gradlew
└── gradlew.bat
However, I would like to change it to so:
.
├── gradle
| ├── build.gradle
│ ├── settings.gradle
│ ├── gradle.properties
│ └── wrapper
│ ├── gradlew
│ ├── gradlew.bat
│ ├── gradle-wrapper.jar
│ └── gradle-wrapper.properties
└── src
├── main
└── test
Other than the fact that I don't know how to tell IntelliJ about the folder structure, I don't know how to change it for Gradle since the Environment Options related with changing the folder structure are deprecated:
-b, --build-file (deprecated)
Specifies the build file. For example: gradle --build-file=foo.gradle. The default is build.gradle, then build.gradle.kts.
-c, --settings-file (deprecated)
Specifies the settings file. For example: gradle --settings-file=somewhere/else/settings.gradle
You can't tell Gradle and Intellij IDEA that you use a non-standard Gradle build layout. And in all honesty, you shouldn't even consider that unless you have strong reasons to do so. There are mainly two reasons for that:
Developers familiar with one Gradle project feel immediately at home when starting with your Gradle project.
A non-standard build file and directory layout requires additional logic in IDE's (which is not present) and requires to provide extra parameters when building on the command line.
To put things into context, please have look at Gradle issue #16402.
Deprecate command-line options that describe the build layout
The -b and -c command-line options are effectively used to describe a non-standard build layout to Gradle. This is problematic because it means that a specific combination of options must be used whenever Gradle is used on that build, for example whenever invoked from the IDE, CI, command-line or some other tool. These command-line options also have some potentially surprising behaviours, such as running a settings script present in the target directory.
We don't think there are any use cases that are strong enough to justify keeping these options, and we should remove them (via deprecation). If we discover there are some use cases, we might consider replacing the options with more self-describing contracts, for example conventions for build script names.
I have a golang application structure like this:
.
├── calc
│ ├── go.mod
│ ├── main.go
│ └── Makefile
├── go.mod
├── LICENSE
├── num
│ ├── go.mod
│ └── num.go
└── README.md
Where calc is an "application" where I'm importing the num package to add 2 numbers.
calc/go.mod
go 1.15
require github.com/github_username/goapp/num v0.2.1
num/go.mod
module github.com/github_username/goapp/num/v0.2.1
go 1.15
go.mod
module github.com/github_username/goapp/v0.2.1
go 1.15
When in /calc, and I run go run main.go, I get the following:
go: github.com/github_username/goapp/num#v0.2.1: reading github.com/github_username/goapp/num/num/go.mod at revision num/v0.2.1: unknown revision num/v0.2.1
What am I doing wrong? The github repo has the annotated tags.
For further context, I'm mimicking a production setup where we have six different mini golang services in folders such as calc, calc2, etc. where each "calc" service has a go.mod file.
module github.com/github_username/goapp/num/v0.2.1
Is nonsense. The semver version tag "v0.2.1" does not belong into the module name.
(Note that for major versions > 1, e.g. 4.3.1, the major version becomes part of the name like in module github.com/user/proj/folder/v4).
And one more: There are no source code belonging to the root go.mod so this module makes no sense whatsoever.
You really should not make that many modules.
Are you working with private repositories?
if yes, then you need to configure OAuth authentication:
export GITHUB_TOKEN=MY_GITHUB_TOKEN
git config --global url."https://${GITHUB_TOKEN}:x-oauth-basic#github.com/".insteadOf "https://github.com/"
Now, if you don't have the necessity to use private repositories!
Turn your repositories to the public that will solve the problem too.
I have a repository structure as follows :-
xyz/src
1. abc
- p
- q
- r
2. def
- t
- u
- v
3. etc
- o
- m
- n
I have created a .mod file in src and run go build ./...
Except for local packages everything is fine. So if abc/p is being used in def then it throws the following exception :- cannot find module providing package abc/p. The idea behind keeping the .mod file in src package was to make sure the path is being found from where the mod file is located. Can anyone suggest where should the mod file ideally should be? also i tried placing it one directory above in xyz but still same issue as well as i created one for each sub directory. I am bit confused on this. Will I have to create separate repository for abc and etc. But considering gopath which earlier used to work for the same I think module should also be able to do the same. Any suggestions?
The most common and easiest approach is a single go.mod file in your repository, where that single go.mod file is placed in the root of your repository.
Russ Cox commented in #26664:
For all but power users, you probably want to adopt the usual convention that one repo = one module. It's important for long-term evolution of code storage options that a repo can contain multiple modules, but it's almost certainly not something you want to do by default.
The Modules wiki says:
For example, if you are creating a module for a repository
github.com/my/repo that will contain two packages with import paths
github.com/my/repo/foo and github.com/my/repo/bar, then the first
line in your go.mod file typically would declare your module path as
module github.com/my/repo, and the corresponding on-disk structure
could be:
repo/
├── go.mod <<<<< Note go.mod is located in repo root
├── bar
│ └── bar.go
└── foo
└── foo.go
In Go source code, packages are imported using the full path including
the module path. For example, if a module declared its identity in its
go.mod as module github.com/my/repo, a consumer could do:
import "example.com/my/repo/bar"
That imports package bar from the module github.com/my/repo.
I have a single go.mod in the root of my go application. I am using the following structure inspired by Kat Zien - How Do You Structure Your Go Apps
At the minute one of my applications looks like this
.
├── bin
├── cmd
│ ├── cli
│ └── server
│ └── main.go
├── pkg
│ ├── http
│ │ └── rest
| │ # app-specific directories excluded
│ └── storage
│ └── sqlite
All packages are imported via their full path, i.e. import "github.com/myusername/myapp/pkg/http/rest" otherwise it causes problems all over the place and this was the one change I had to make going from $GOPATH to go mod.
go mod then handles all the dependencies it discovers properly as far as I've discovered so far.
my working tree is like this:
/opt/go/src/tb-to-composer/
├── apis
│ └── rtb.go
├── config.yaml
├── jsondef
│ └── structures.go
├── LICENSE.md
├── README.md
├── tb-to-composer
└── thingsToComposer.go
when I do go build inside /opt/go/src/tb-to-composer/ the build doesn't recompile rtb.go and structures.go even though there was changes in them. In order to achieve build I need to run go build -a every time I do a change to rtb.go or structures.go, is that the expected behavior from go build? How to I recompile only custom libs inside my package folder without recompile the whole /opt/go/src tree?
You can try the -i flag, or (this does not work, sorry) specify the files in the directories explicitly as arguments to go build, i.e. go build thingsToComposer.go apis/rtb.go jsondef/structures.go
I’ve tried to add a package to Buildroot that uses Qt and Boost. The package uses qmake to generate a Makefile, this part seems to be working, however I get an error when I build saying:
Could not find qmake configuration file qws/linux-arm-g++.
Error processing project file: MsgDisplay.pro
The contents of my package is laid out like this:
DummyPgm
├── main.cpp
├── MsgDisplay.pri
├── MsgDisplay.pro
├── MsgDisplay.pro.user
├── MsgHandler.cpp
├── MsgHandler.h
├── MsgServer.cpp
├── MsgServer.h
├── Tcp
│ ├── TcpAddrPort.cpp
│ ├── TcpAddrPort.h
│ ├── TcpServer.cpp
│ ├── TcpServer.h
│ ├── TcpSocket.cpp
│ └── TcpSocket.h
└── Tools
├── Banner.cpp
├── Banner.h
├── IoExt.h
├── SeparateArgumentList.cpp
├── SeparateArgumentList.h
└── SysTypes.h
2 directories, 20 files
I have added a package directory, dummypgm, which contains Config.in and dummypgm.mk files. The contents of the files are:
Config.in:
config BR2_PACKAGE_DUMMYPGM
bool "dummypgm"
help
Foo Software.
http://www.foo.com
dummypgm.mk:
DUMMYPGM_VERSION = 0.1.0
DUMMYPGM_SOURCE = DummyPgm-$(DUMMYPGM_VERSION).tar.gz
define DUMMYPGM_CONFIGURE_CMDS
(cd $(#D); $(QT_QMAKE) MsgDisplay.pro)
endef
define DUMMYPGM_BUILD_CMDS
$(MAKE) -C $(#D)
endef
$(eval $(generic-package))
Since the package is hosted locally, I’ve simply put the DummyPgm-0.1.0.tar.gz in the dl directory.
I’ve also added the following to package/Config.in:
source "package/dummypgm/Config.in"
I’m a little lost as to why this doesn’t work, if anyone could help me I would be very grateful. Also, is there any way to call $(eval $(qmake-package)) or something?
Are you using Qt4 or Qt5 ? Your package/dummypgm/Config.in should have a depends on on one of them, and your dummypgm.mk should have a DUMMYPGM_DEPENDENCIES = qt or DUMMYPGM_DEPENDENCIES = qt5base.
My intuition is that you are using Qt5. In this case, you shouldn't call $(QT_QMAKE), but $(QT5_QMAKE).
Have a look at http://git.buildroot.net/buildroot/tree/package/qextserialport/qextserialport.mk for an example. Note that this example supports both Qt4 and Qt5, probably in your case you only need one of the two.
Also, you should really subscribe to the Buildroot mailing list, you would get a lot more answers than here.