feat(#556): added check circular dependencies

[renanbastos93]

Added validation to ensure that dependencies do not form circular dependencies.
An error is raised if such a condition is detected.

ISSUE: #556
Repository reference to simulate it: https://github.com/renanbastos93/weaver-issue-556

[renanbastos93]

@mwhittaker @sysulq @rgrandl

Does anyone have comments on this? Is it good, or do I need to change this commit?

[rgrandl]

@renanbastos93, thanks for the PR.

Few comments:

1. We already have a graph package, so we would prefer not to get a dependency on another graph library (github.com/dominikbraun/graph)
2. A better place to check for circular dependencies is in the deployer. For example, in the multi deployer, you can do the check when you read the component graph https://github.com/ServiceWeaver/weaver/blob/main/internal/tool/multi/deployer.go#L250. Similar path should exist for the other deployers.

[renanbastos93]

@renanbastos93, thanks for the PR.

Few comments:

1. We already have a graph package, so we would prefer not to get a dependency on another graph library (github.com/dominikbraun/graph)
2. A better place to check for circular dependencies is in the deployer. For example, in the multi deployer, you can do the check when you read the component graph https://github.com/ServiceWeaver/weaver/blob/main/internal/tool/multi/deployer.go#L250. Similar path should exist for the other deployers.

awesome, i will use that. Thanks a lot soon i will do a new commit.

[renanbastos93]

@rgrandl done, check please.

[rgrandl]

Sorry for the late reply on this, Renan.

In dfs.go, we have a dfs function that does a DFS traversal of the graph already. Is it possible to modify that function to detect cycles instead of implementing another traversal?

[renanbastos93]

Sorry for the late reply on this, Renan.

In dfs.go, we have a dfs function that does a DFS traversal of the graph already. Is it possible to modify that function to detect cycles instead of implementing another traversal?

No worries! I can do this, but I will need more time because I've started a new job and my free time has been limited.