I'm working on a system where I can't add a new module by adding it's path to sys.path. Instead, I want to place the module in the same folder as the files using it, and then import the module on runtime using imp or importlib (or similar).
I've tried to use both imp and importlib, but can not get it to work. Time will tell if I'm just misinterpreting how and what params to specify when using either of the two libraries.
The folder structure for my project is defined like this:
root-folder-in-sys-path/
- file1.py
- file2.py
- file3.py
- my-module/
--- __init__.py
--- helper1.py
--- helper2.py
As my example indicates, the root folder is part of sys.path. The files (file1.py etc.) is part of the system and is from where I need access to the module. Only files that contains classes of a specific type is added, so it will not be possible just to add the module files in the root to load them, as they will be ignored. Best case would be if helper1.py to helper-n.py is made available - otherwise It is ok if only one is loaded.
Thanks.
I was able to come up with a solution that loads anyone of the helpers. I guess it could easily be made into a package with many more modules this way as well.
To for example access helper1.py in file1.py, this will work:
import os.path, imp
path = os.path.abspath(os.path.join(os.path.dirname(__file__), "my-module/helper1.py"))
im = imp.load_source("helper1", path)
If you find a better solution, then please let me know!
I have an ember app, and a folder with a file playGame/game.js. This file includes game logic, and I want to import it for asset compilation.
If this file is under app/playGame/game.js and my Brocfile is like this:
app.import('app/playGame/game.js')
this gives the error, path or pattern app/playGame/game.js didn't match any files..
but if I put the file under bower_components/playGame/game.js and my Brocfile:
app.import('bower_components/playGame/game.js'), this compiles successfully.
What is the problem and solution here?
There are two parts to this:
Where should I put my file to import it as an asset?
Why isn't putting it in my app-folder working?
The way to do what you want is to create a folder called vendor in your root, put the file somewhere in there, and then import it in your Brocfile.js like so:
app.import('vendor/playGame/game.js');
This is documented on ember-cli.com, although somewhat hidden.
You could also put it in bower_components, but that folder is for things installed with bower, and could theoretically be deleted (in fact, this is a common recommendation to various issues). Things in bower_components is also not checked in to version control by default, which you probably want to do in this case.
This should solve your issue.
Now, why doesn't it work to put it in /app?
app is a special folder. From the documentation:
Contains your Ember application’s code. Javascript files in this
folder are compiled through the ES6 module transpiler and concatenated
into a file called app.js.
This is what makes it possible for you to import stuff from within your app. The folders in app is available directly under your <appname> namespace, along with some other files and folders like config/environment.
Example:
import myWidget from 'my-app/widgets/my-widget';`
The referenced file is /app/widgets/my-widget.js.
The ember-cli website has some more resources for how to use modules. Read those if this doesn't make any sense.
To sum up:
You could put your file in app, but that would make it part of your transpiled package, and you'd have to use it that way internally with an export and everything else that comes with it. It would end up as part of <appname>.js
You could put your file in vendor and import it in your Brocfile.js as explained above. It would be part of vendor.js and load before your app code.
Even though I have GOPATH properly set, I still can't get "go build" or "go run" to find my own packages. What am I doing wrong?
$ echo $GOROOT
/usr/local/go
$ echo $GOPATH
/home/mitchell/go
$ cat ~/main.go
package main
import "foobar"
func main() { }
$ cat /home/mitchell/go/src/foobar.go
package foobar
$ go build main.go
main.go:3:8: import "foobar": cannot find package
It does not work because your foobar.go source file is not in a directory called foobar. go build and go install try to match directories, not source files.
Set $GOPATH to a valid directory, e.g. export GOPATH="$HOME/go"
Move foobar.go to $GOPATH/src/foobar/foobar.go and building should work just fine.
Additional recommended steps:
Add $GOPATH/bin to your $PATH by: PATH="$GOPATH/bin:$PATH"
Move main.go to a subfolder of $GOPATH/src, e.g. $GOPATH/src/test
go install test should now create an executable in $GOPATH/bin that can be called by typing test into your terminal.
Although the accepted answer is still correct about needing to match directories with package names, you really need to migrate to using Go modules instead of using GOPATH. New users who encounter this problem may be confused about the mentions of using GOPATH (as was I), which are now outdated. So, I will try to clear up this issue and provide guidance associated with preventing this issue when using Go modules.
If you're already familiar with Go modules and are experiencing this issue, skip down to my more specific sections below that cover some of the Go conventions that are easy to overlook or forget.
This guide teaches about Go modules: https://golang.org/doc/code.html
Project organization with Go modules
Once you migrate to Go modules, as mentioned in that article, organize the project code as described:
A repository contains one or more modules. A module is a collection of
related Go packages that are released together. A Go repository
typically contains only one module, located at the root of the
repository. A file named go.mod there declares the module path: the
import path prefix for all packages within the module. The module
contains the packages in the directory containing its go.mod file as
well as subdirectories of that directory, up to the next subdirectory
containing another go.mod file (if any).
Each module's path not only serves as an import path prefix for its
packages, but also indicates where the go command should look to
download it. For example, in order to download the module
golang.org/x/tools, the go command would consult the repository
indicated by https://golang.org/x/tools (described more here).
An import path is a string used to import a package. A package's
import path is its module path joined with its subdirectory within the
module. For example, the module github.com/google/go-cmp contains a
package in the directory cmp/. That package's import path is
github.com/google/go-cmp/cmp. Packages in the standard library do not
have a module path prefix.
You can initialize your module like this:
$ go mod init github.com/mitchell/foo-app
Your code doesn't need to be located on github.com for it to build. However, it's a best practice to structure your modules as if they will eventually be published.
Understanding what happens when trying to get a package
There's a great article here that talks about what happens when you try to get a package or module: https://medium.com/rungo/anatomy-of-modules-in-go-c8274d215c16
It discusses where the package is stored and will help you understand why you might be getting this error if you're already using Go modules.
Ensure the imported function has been exported
Note that if you're having trouble accessing a function from another file, you need to ensure that you've exported your function. As described in the first link I provided, a function must begin with an upper-case letter to be exported and made available for importing into other packages.
Names of directories
Another critical detail (as was mentioned in the accepted answer) is that names of directories are what define the names of your packages. (Your package names need to match their directory names.) You can see examples of this here: https://medium.com/rungo/everything-you-need-to-know-about-packages-in-go-b8bac62b74cc
With that said, the file containing your main method (i.e., the entry point of your application) is sort of exempt from this requirement.
As an example, I had problems with my imports when using a structure like this:
/my-app
├── go.mod
├── /src
├── main.go
└── /utils
└── utils.go
I was unable to import the code in utils into my main package.
However, once I put main.go into its own subdirectory, as shown below, my imports worked just fine:
/my-app
├── go.mod
├── /src
├── /app
| └── main.go
└── /utils
└── utils.go
In that example, my go.mod file looks like this:
module git.mydomain.com/path/to/repo/my-app
go 1.14
When I saved main.go after adding a reference to utils.MyFunction(), my IDE automatically pulled in the reference to my package like this:
import "git.mydomain.com/path/to/repo/my-app/src/my-app"
(I'm using VS Code with the Golang extension.)
Notice that the import path included the subdirectory to the package.
Dealing with a private repo
If the code is part of a private repo, you need to run a git command to enable access. Otherwise, you can encounter other errors This article mentions how to do that for private Github, BitBucket, and GitLab repos: https://medium.com/cloud-native-the-gathering/go-modules-with-private-git-repositories-dfe795068db4
This issue is also discussed here: What's the proper way to "go get" a private repository?
I solved this problem by set my go env GO111MODULE to off
go env -w GO111MODULE=off
Note: setting GO111MODULE=off will turn off the latest GO Modules feature.
Reference: Why is GO111MODULE everywhere, and everything about Go Modules (updated with Go 1.17)
GO111MODULE with Go 1.16
As of Go 1.16, the default behavior is GO111MODULE=on, meaning that if
you want to keep using the old GOPATH way, you will have to force Go
not to use the Go Modules feature:
export GO111MODULE=off
In the recent go versions from 1.14 onwards, we have to do go mod vendor before building or running, since by default go appends -mod=vendor to the go commands.
So after doing go mod vendor, if we try to build, we won't face this issue.
Edit: since you meant GOPATH, see fasmat's answer (upvoted)
As mentioned in "How do I make go find my package?", you need to put a package xxx in a directory xxx.
See the Go language spec:
package math
A set of files sharing the same PackageName form the implementation of a package.
An implementation may require that all source files for a package inhabit the same directory.
The Code organization mentions:
When building a program that imports the package "widget" the go command looks for src/pkg/widget inside the Go root, and then—if the package source isn't found there—it searches for src/widget inside each workspace in order.
(a "workspace" is a path entry in your GOPATH: that variable can reference multiple paths for your 'src, bin, pkg' to be)
(Original answer)
You also should set GOPATH to ~/go, not GOROOT, as illustrated in "How to Write Go Code".
The Go path is used to resolve import statements. It is implemented by and documented in the go/build package.
The GOPATH environment variable lists places to look for Go code.
On Unix, the value is a colon-separated string.
On Windows, the value is a semicolon-separated string.
On Plan 9, the value is a list.
That is different from GOROOT:
The Go binary distributions assume they will be installed in /usr/local/go (or c:\Go under Windows), but it is possible to install them in a different location.
If you do this, you will need to set the GOROOT environment variable to that directory when using the Go tools.
TL;DR: Follow Go conventions! (lesson learned the hard way), check for old go versions and remove them. Install latest.
For me the solution was different. I worked on a shared Linux server and after verifying my GOPATH and other environment variables several times it still didn't work. I encountered several errors including 'Cannot find package' and 'unrecognized import path'. After trying to reinstall with this solution by the instructions on golang.org (including the uninstall part) still encountered problems.
Took me some time to realize that there's still an old version that hasn't been uninstalled (running go version then which go again... DAHH) which got me to this question and finally solved.
Running go env -w GO111MODULE=auto worked for me
Without editing GOPATH or anything, in my case just worked the following:
/app
├── main.go
├── /utils
└── utils.go
Import packages where needed. This can be unintuitive, because it isn't relative to the app path. You need to add the app in the package path too:
main.go:
package main
import(
"app/util"
)
Being in app directory, run:
go mod init app
go get <package/xxx>
go build main.go / go run main.go
You should be good to go.
GOPATH = /home/go
appPath = /home/projects/app
Create a proper go.mod and go.sum with go mod init app (delete old before)
After that resolve all dependencies like missing packages with go get github.com/example/package.
In simple words you can solve the import problem even with GO111MODULE=on with the following syntax for import:
import <your_module_name>/<package_name>
your_module_name -> module name which can be found in the go.mod file of the module as the first line.
example: github.com/nikhilg-hub/todo/ToDoBackend
package_name -> Path to your package within module.
example: orm
So the import statement would look like:
import "github.com/nikhilg-hub/todo/ToDoBackend/orm"
According to me we need to specify the module name + package name because we may need a same package name in two or more different modules.
Note: If you are importing a package from same module still you need to specify the full import path like above.
If you have a valid $GOROOT and $GOPATH but are developing outside of them, you might get this error if the package (yours or someone else's) hasn't been downloaded.
If that's the case, try go get -d (-d flag prevents installation) to ensure the package is downloaded before you run, build or install.
GOROOT should be set to your installation directory (/usr/local/go).
GOPATH should be set to your working directory (something like /home/username/project_folder).
GOPATH should not be set to GOROOT as your own project may need to install packages, and it's not recommended to have those packages in the Go installation folder. Check out this link for more.
For me none of the above solutions worked. But my go version was not the latest one. I have downloaded the latest version and replaced the older version in my mac os after that it worked perfectly.
I had a similar problem when building a docker file:
[1/3] STEP 9/9: RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -a -o manager main.go
api/v1alpha1/XXX.go:5:2: cannot find package "." in:
/workspace/client/YYY/YYY.go
This only appeared when building the Dockerfile, building locally worked fine.
The problem turned out to be a missing statement in my Dockerfile:
COPY client/ client/
I do not understand why this happens, we must be able to import from wherever our file is in its nest, since I have discovered that if we have more than one nest this will throw an error.
package main
import (
"fmt"
"indexer/source/testPackage3" // this will be show a GOROOT error.
"indexer/testPackage"
"indexer/testPackage2"
)
func main() {
fmt.Println("Agile content indexer -")
fmt.Println(testPackage.Greeting())
fmt.Println(testPackage2.Greeting())
fmt.Println(testPackage3.Greeting())
}
├── testPackage2
│ ├── entry2.go
│ └── source
│ └── entry3.go
To conclude, I just want to tell you, the entry3.go file will not work when imported into my main file, which in this case is (main.go), I do not understand why, therefore, I have simply chosen to use a depth folder in the packages I need to export.
entry.go, entry2.go will work perfectly when imported, but entry3.go will not work..
In addition, both the directory and the name of the package must be the same so that they work properly when importing them.
Have you tried adding the absolute directory of go to your 'path'?
export PATH=$PATH:/directory/to/go/
I am venturing into the land of creating C/C++ bindings for Python using pybindgen. I've followed the steps outlined under "Building it ( GCC instructions )" to create bindings for the sample files:
http://packages.python.org/PyBindGen/tutorial.html#a-simple-example
Running make produces a .so file. If I understand how .so files work, I should be able to import the classes in the shared object into Python. However, I'm not sure where to place the file and how to let Python know where it is. Additionally, do the original c/c++ source files need to accompany the .so file?
So far I've tried placing the file in /usr/local/lib and adding that path to DYLD_LIBRARY_PATH to the .bash_profile. When I try to import the module from within the Python interpeter an error is thrown stating that the module can not be found.
So, my question is: What needs to be done with the generated .so file in order for it to be used by a Python program?
Python looks for .so modules in the same directories where it searches python ones. So you have to install it as you would normal python module either somewhere that is on python's sys.path by default (/usr/share/python/site-lib or something like that—it'd distribution-dependent) or add the directory to PYTHONPATH environment variable.
It's python that's loading the module using dlopen, not the dynamic linker, so LD_LIBRARY_PATH (note, there is no DY) won't help you.
Same as all other Python modules. It must be within one of the locations given in sys.path.
I'm running into an import issue that as a relative newcomer to the Objective-C/C++/XCode world I haven't seen before.
I'd like to include this library with my project: https://github.com/jdkoftinoff/jdksmidi
But, it seems like no matter how I try to add it to the project, I get errors when I try to import:
#import "jdksmidi/world.h"
(No such file or directory)
I can import without the jdksmidi subdirectory, but since inside all of the headers included with the library, the author uses the same syntax with the subdirectory, I'm stuck.
Simplified question: how do I add the library to my project so that I can use the #import "jdksmidi/___FILE____.h" format and not throw compiler errors?
Thanks
You probably need to adjust your User Header Search Paths (USER_HEADER_SEARCH_PATHS) in your build settings. Make sure that the folder containing jdksmidi is in the path. Hope that helps.
you need add your jdksmidi/world.h file in project, just drag'n'drop it into your groups & files section. Or you can use #include directive