# Passing reference or whole directory as input?

**URL:** <https://cwl.discourse.group/t/passing-reference-or-whole-directory-as-input/64>\
**Category:** CWL Questions\
**Created:** [November 4, 2019, 5:52pm UTC](https://cwl.discourse.group/t/passing-reference-or-whole-directory-as-input/64 "2019-11-04T17:52:54Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Paul\_Biociphers](https://yyz2.discourse-cdn.com/free1/user_avatar/cwl.discourse.group/paul_biociphers/32/47_2.png) [@Paul\_Biociphers](https://cwl.discourse.group/u/Paul_Biociphers)\
**Post date:** [November 4, 2019, 5:52pm UTC](https://cwl.discourse.group/t/passing-reference-or-whole-directory-as-input/64/1 "2019-11-04T17:52:54Z")

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Good Afternoon,

Apologies for the newbie question. I am trying to set up CWL with my set of tools so I am going through a kind of boot camp now. 🙂

One of my tools works by having a directory specified in a config file (a config file for the inner program) which will contain many files that the program will read. So for example the program will have a config file with:

[settings]  
main\_dir=/path/to/some/data/dir

I pass in this settings file itself through the usual CWL “class: File” method which works as expected. What I need to do is also pass in as input the data directory. So for example, I may have in the config file that is passed in:

[settings]  
main\_dir=data\_dir

And then include an input in the CWL file like:  
inputs:  
dataDir:  
type: Directory

(and in settings)  
dataDir:  
class: Directory  
path: /actual/absolute/path/to/data/dir/with/data/files

This runs without error, but the actual data directory does not seem to be passed, or at least I think I am using “Directory” incorrectly. I have tries testing with “tree” and “ls” commands and only one temp file is shown - no directory. How can I make this directory location available to the program either by copying it or using a symlink? Is there a way to include a whole directory?

Thanks for reading and have an awesome day!

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**Author:** ![ttubb](https://yyz2.discourse-cdn.com/free1/user_avatar/cwl.discourse.group/ttubb/32/37_2.png) [@ttubb](https://cwl.discourse.group/u/ttubb)\
**Post date:** [November 4, 2019, 7:08pm UTC](https://cwl.discourse.group/t/passing-reference-or-whole-directory-as-input/64/2 "2019-11-04T19:08:54Z")

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Hi Paul!

Let’s start by what is happening when you run your tool in its current form: During runtime, your cwl-runner will create a temporary directory in which the `CommandLineTool` operates and writes output. Symlinks to input Files/Directories are passed to the Tool. If a config file specifies an absolute path, the Tool will not be able to find it because it does not have access to anything outside the temporary directory.

We can use an `InitialWorkDirRequirement` and relative paths to adress the issue:

```
requirements:
  InitialWorkDirRequirement:
    listing:
      - $(inputs.dataDir)

inputs:
  settings:
    type: File
    inputBinding: 
      [...omitted, because i don't know how the tool works...]
  dataDir:
    type: Directory

```

This allows us to pass dataDir as in input parameter to the `CommandLineTool` in the job file. The cwl-runner will place it in the temporary folder where the tool runs. You can then specify a relative path to the data directory (in this case `./nameOfDataDir`) in the settings file.

I had to do a very similar thing for the `necat` assembler, maybe the workflow and tools can help you as an additional example: [https://github.com/ttubb/autopore/blob/f5b2d90dc52acc1565c6ac42fd639a3f9e8b5fe4/cwl-tools/assembly/necatWorkflow.cwl](https://github.com/ttubb/autopore/blob/f5b2d90dc52acc1565c6ac42fd639a3f9e8b5fe4/cwl-tools/assembly/necatWorkflow.cwl)

To make the whole workflow more elegant, you might consider writing a short script which creates the settings file at runtime according to the input provided in the cwl-job.

I hope this post is helpful. Feel free to ask follow-up questions! Figuring this scenario out for the first time gave me a headache.

Cheers  
Tom

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**Author:** ![tetron](https://yyz2.discourse-cdn.com/free1/user_avatar/cwl.discourse.group/tetron/32/40_2.png) [@tetron](https://cwl.discourse.group/u/tetron)\
**Post date:** [November 4, 2019, 10:33pm UTC](https://cwl.discourse.group/t/passing-reference-or-whole-directory-as-input/64/3 "2019-11-04T22:33:51Z")

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Welcome @Paul_Biociphers !

When you pass in files and directories as input, you don’t know where they will be staged to ahead of time. So either you can stage them under a known name in the working directory (as suggested by @ttubb) or you can create a configuration file with the correct paths on the fly:

```auto
class: CommandLineTool
inputs:
  dataDir: Directory
requirements:
  InitialWorkDirRequirement:
    listing:
      - entryname: config.ini
        entry: |
          [settings]
          main_dir=$(inputs.dataDir.path)
arguments: ["my_program", "config.ini"]

```

Hope this helps!