Issue links - what is the meaning of "inward" and "outward"

[Trudy Claspill]

When creating an issue link type, I understand that the inward and outward descriptions clarify the relationship between the issue; i.e. A blocks B, and B is blocked by A.

What I don't understand is if it matters which description is "inward" and which is "outward"?

Is there some implied meaning behind those terms? Is JIRA core using the "inward description" for some purpose, and/or the "outward description" for some other purpose

[Jonathan MacDonald]

The Inward/Outward refers to the directionality of the relationship as it is stored in the database. The table that stores issue links (issuelink) has a source issue id and a destination issue id. The outward relationship refers to the relation from source to destination, and the inward relationship refers to the relation from destination to source.

The outward relationship tends to be the relationship that is the causal direction, meaning the source issue is taking action on the destination issue.

i.e. the source issue can block, clone, duplicate, relate, resolve etc.

The inward relationship tends to describe the issue that was acted upon. 

i.e. the destination issue was blocked by, cloned by, duplicated by, related to, and resolved by etc.

[Joseph Miner]

Great explanation. Very helpful.

[David Sumlin]

I know this is an old post, but I've found two reasons to get the outward and inward designation correct.

1 - It makes importing related issues more difficult

When importing issues via CSV, the CSV importer always uses the outward designation. It assumes that you're importing issues that are related to pre-existing issues, therefore, your new issues are probably the issues that block, impact, resolve, are children of, etc to existing issues.

2 - Addon JQL functions that use the link type 

Some JQL functions have a link type parameter. The addon documentation will usually give you an example of how to use the function. 

• Examples
  • Issue Link Functions for JQL Tricks
  • Issue Link Functions for ScriptRunner for Jira

The problem is that if you reverse your outward and inward designations, then the JQL syntax needs to be reversed to what the user expects it to be. This can make the function syntax look "wrong" and can be difficult to explain to users during support.

Conclusion

If you setup your Jira and start adding and using links and get the outward vs inward designation backwards, the users "may" never notice, but your CSV imports and JQL syntax will become more difficult.  (lessons learned and still dealing with) 

[Nic Brough -Adaptavist-]

I suspect that the inward and outward thing is probably partly inherited from the code and how the language is used in there.  Sadly, it's still quite fuzzy on what the exact difference is.

Links are directional, and the inward/outward thing is supposed to tell us which direction you are looking at.  For example, if you have a link of "Block", you are using it to say "Issue A is blocked by B".  That description is only half the story, because you can also say "Issue B is blocking A".   So it distinguishes between the two points of view.

But it doesn't really tell us which is which, as you could swap the descriptions of those without changing the inward/outward.

So, the answer is only partial.  The inward/outward is about the directionality of the link, but I am not sure which way round it is.

[Dugald Morrow]

Hi @Nic Brough (Adaptavist) , @Alexey Matveev , @Jonathan MacDonald and @David Sumlin , I also became confused by issue link data returned from Jira's API so I investigated and created a blog on the topic:

https://blog.developer.atlassian.com/jira-issue-linking-model/

I hope this helps,

Regards,

Dugald

[Mike Quentel]

A bit of a dark way to remember...shooter vs target...

1. A blocks B: the Outward Issue is B...might be easier to imagine the Outward Issue as being the target. Can imagine A shoots B. So Outward Issue == target ..."A" is for "Attacker".
2. B is blocked by A: the Inward Issue is A...it is the incoming, attacking force; it is the "active shooter". Can imagine B is being shot by A's incoming bullets. So Inward Issue == shooter ...the shooter A is charging in to attack B

One way to examine these relationships is through the REST API: $SERVER/rest/api/2/search?jql=key = $SOME_KEY_YOU_WANT_TO_EXAMINE where $SERVER is the base URL of your Jira instance, and $SOME_KEY_YOU_WANT_TO_EXAMINE is a key that has Inward and/or Outward relationships.

And in maybe 6 months, I will be searching for this very post to refresh my memory, again.

[Jason Dunn]

thanks for actually answering the question

[Adan Warren]

A neat description but something a lot of people seem to misunderstand (and your comment doesn't really help) is that the issues themselves are not inward or outward. Rather, the relationship itself is inward/outward depending on the perspective.

For the example of A shoots B:

• A is outward to B
• B is inward from A
• A is not an "outward issue" and B is not an "inward issue". Instead focus on the directionality of the link.

The easy rule of thumb is: "Which of these two issues affects the other by what it does?" The acting issue has an outward link to the affected issue.

A parent issue or an epic is not an inward issue, but it will have a lot of inward relationships from other issues. Likewise, those children issues will be outward to the parent or epic. "Causes", "supersedes", "tests", "contained within", etc. are all outward links because they have an effect on the other issue.

[Eugene Geis]

Finally... 

It took so long for one person to acknowledge the fact that every single issue has BOTH and inward and outward relationship with the linked issue. Which are the two objects the Jira API returns for every issuelink.

I came here for clarification of what I intuitively thought it was... you're the first to answer the question!

[Alexey Matveev]

Hello,

When you make a link between issues, one of the issues has the outward connection and the other one has the inward connection. You have these two connections because if you have a link called Blocks, then one issue is blocking the other issue and the other issue is blocked by first issue. That is why you need two different descriptions.

[Trudy Claspill]

Hello Alexey,

As I stated, I understand the need for two descriptions. I don't understand the use of the terms "inward" and "outward". What is the relevance of the terminology? Is JIRA executing some functionality based on "inward" and "outward"?

[Alexey Matveev]

As @Nic Brough -Adaptavist- said, it might be a way of coding links. I think it is the same like why we call transitions from statuses outgoing and incoming. Somebody just named it like this.