navsection: adminguide
title: Cheat Sheet
navorder: 1
----
+...
h1. Cheat Sheet
{
"tail_kind":"arvados#user",
"tail_uuid":"$user_uuid",
- "head_kind":"arvados#virtual_machine",
+ "head_kind":"arvados#virtualMachine",
"head_uuid":"$vm_uuid",
"link_class":"permission",
"name":"can_login",
navmenu: Concepts
title: Resources
navorder: 4
----
+...
h1. Resources
table(table table-bordered table-condensed).
|*Attribute*|*Type*|*Description*|*Example*|
- |kind|string|@arvados#{resource_type}_list@|@arvados#project_list@|
+ |kind|string|@arvados#{resource_type}List@|@arvados#projectList@|
|etag|string|The ETag[1] of the resource list|@cd3o1wi9sf934saajykawrz2e@|
|self_link|string|||
|next_page_token|string|||
navmenu: Schema
title: Link
navorder: 12
----
+...
h1. Link
**Links** describe relationships between Arvados objects, and from objects to primitives.
- Links are directional: each metadata object has a tail (subject), class, name, properties, and head (object or value). A Link may describe a relationship between two objects in an Arvados database: e.g. a _permission_ link between a User and a Group defines the permissions that User has to read or modify the Group. Other Links simply represent metadata for a single object, e.g. the _identifier_ Link, in which the _name_ property represents a human-readable identifier for the object at the link's head.
+ Links are directional: each metadata object has a tail (the "subject" being described), class, name, properties, and head (the "object" that describes the "subject"). A Link may describe a relationship between two objects in an Arvados database: e.g. a _permission_ link between a User and a Group defines the permissions that User has to read or modify the Group. Other Links simply represent metadata for a single object, e.g. the _identifier_ Link, in which the _name_ property represents a human-readable identifier for the object at the link's head.
For links that don't make sense to share between API clients, a _link_class_ that begins with @client@ (like @client.my_app_id@ or @client.my_app_id.anythinghere@) should be used.
navmenu: Tutorials
title: "Running external programs"
navorder: 18
----
+...
h1. Running external programs
*This tutorial assumes that you are "logged into an Arvados VM instance":{{site.basedoc}}/user/getting_started/ssh-access.html#login, and have a "working environment.":{{site.basedoc}}/user/getting_started/check-environment.html*
+ In this tutorial, you will use the external program @md5sum@ to compute hashes instead of the built-in Python library used in earlier tutorials.
+
Start by entering the @crunch_scripts@ directory of your git repository:
<notextile>
<pre><code>$ <span class="userinput">cd you/crunch_scripts</span>
</code></pre>
</notextile>
-
- Next, using your favorite text editor, create a new file called @run-md5sum.py@ in the @crunch_scripts@ directory. Add the following code to compute the md5 hash of each file in a collection:
+
+ Next, using your favorite text editor, create a new file called @run-md5sum.py@ in the @crunch_scripts@ directory. Add the following code to use the @md5sum@ program to compute the hash of each file in a collection:
<pre><code class="userinput">{% include run-md5sum.py %}</code></pre>
navmenu: Tutorials
title: "Writing a Crunch script"
navorder: 13
----
+...
h1. Writing a Crunch script
Next, on the Arvados virtual machine, clone your git repository:
<notextile>
- <pre><code>$ <span class="userinput">git clone git://git.{{ site.arvados_api_host }}:you.git</span>
+ <pre><code>$ <span class="userinput">git clone git@git.{{ site.arvados_api_host }}:you.git</span>
Cloning into 'you'...</code></pre>
</notextile>