--- title: "Quickly Change Conda Env With Fzf" description: "Changing conda environments is a bit verbose, I use a function with fzf that both lists environments and selects the one I want in one go." date: 2021-01-11 published: true tags: - python template: blog-post --- Changing conda environments is a bit verbose, I use a function with fzf that both lists environments and selects the one I want in one go. ## Conda I have used conda as a virtual environment tool for years now. I started using conda for its simplicity to install packages on windows, but now that has gotten so much better and it's been years since I have run a `conda install` command. I'm sure that I could use a different environment manager, but it works for me and makes sense. > What environment manager do you use for python? Conda environments are stored in a central location such as `~/miniconda3/envs/` and not with the project. They contain both the python interpreter and packages for that env. ## Conda create Conda environments are created with the `conda create` command. At this point, you will need to name your env and select the python version. ``` bash conda create -n my_env python=3.8 ``` After running this command you will have a directory `~/miniconda3/envs/my_env` with a base python install. It will not be active yet. ## List environments Before activating an environment I often want to list the environments that I have installed which are often upwards of 70, so it's hard to remember them all. ``` bash conda info --envs ``` After running this command you will see something like the following. ``` bash # conda environments: # base /home/waylon/miniconda3 my_env /home/waylon/my_env ``` ## Activating an environment Activating a conda environment will do some magic to your current shells `$PATH` variable to ensure that the environment that you select is preferred over the base environment. ``` bash conda activate my_env ``` ## Ready to work Now you can install packages for your project in an isolated environment safe from wrecking another project or being wrecked by another project. ``` bash pip install -r requirements.txt ``` ## Using fzf _a bit less verbose_ [fzf](https://github.com/junegunn/fzf) is an amazing tool for the terminal that is a generic fuzzy matcher. It is super performant and can handle insane amounts of text and is brilliant at figuring out what you mean with just a few characters. We can use it here to list out all of our conda environments and select the one we want to activate with just a few keystrokes. ### Selecting the environment Piping our list of environments directly into `fzf` gives us a fuzzy selection where we can type a few characters and it will return the row we were looking for. ``` bash conda info --envs | fzf ``` This returns us something like this which also includes the path where it is located. ``` bash my_env /home/walkews/miniconda3/envs/my_env ``` ### getting just the environment name To get just the name without the path I pipe the output into awk. There are many ways to do this in bash, this is the way that worked for me at the time I made this function. ``` bash conda info --envs | fzf | awk '{print $1}' ``` ### Time to activate Functions that use `fzf` can be a bit odd, running them in a subshell with the $() syntax generally makes it super simple to utilize the output. No matter how many times I have tried without running it in a subshell it's always buggy without it. ``` bash conda activate "$(conda info --envs | fzf | awk '{print $1}')" ``` This will now run conda activate on the environment that we select with fzf. ### Make it a function We don't want to type that out every time we want to activate an environment. I keep a function called `a` in my `~/.bashrc` and `~/.zshrc` so that I can activate an environment with a single character. Yes, I switch environments often enough to justify the valuable namespace of a single character. ``` bash a () { conda activate "$(conda info --envs | fzf | awk '{print $1}')" } ``` Creating Reusable Bash Scripts > for more information on writing reusable bash scripts check out one of my > favorite articles I am always on the lookout for cool new use cases for `fzf`, if you have one please share it with me.