Added dry-run mode command line option (-n, --dry-run). #283
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When invoked, Docuum will report what images would have been deleted during it's initial vacuuming run at start up then exit. In order to do this, Docuum now creates a list of images to delete ensuring that by deleting them it will meet the space requirements set forth by the user.
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Hi @mardambey, thanks for creating this pull request! I'll review it when I can. In the meantime, would you mind rebasing onto the latest commit on |
This should be up to date with Thank you! |
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Added some initial feedback, but I haven't had time for a full review yet (it might take some time—my apologies).
Since this PR affects how non-dry-run behavior works, we will have to be extremely careful. Some big companies including Netflix and Airbnb rely on this.
| .long(DRY_RUN_OPTION) | ||
| .required(false) | ||
| .takes_value(false) | ||
| .help("Dry run mode, prevents deletion of any images."), |
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For consistency with the other flag descriptions, don't punctuate as a sentence
.help("Dry run mode, prevents deletion of any images"),| @@ -85,6 +85,7 @@ struct ImageRecord { | |||
| parent_id: Option<String>, | |||
| created_since_epoch: Duration, | |||
| repository_tags: Vec<RepositoryTag>, // [ref:at_least_one_repository_tag] | |||
| size: u128, | |||
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For clarity:
size: u128, // In bytes(It is in bytes, right?)
| @@ -96,6 +97,15 @@ struct ImageNode { | |||
| ancestors: usize, // 0 for images with no parent or missing parent | |||
| } | |||
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| // Builds an image's name from as repository:tag | |||
| @@ -928,6 +995,7 @@ mod tests { | |||
| repository: String::from("alpine"), | |||
| tag: String::from("latest"), | |||
| }], | |||
| size: 30000, | |||
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Why not 30_000 for consistency with the other sizes?
| @@ -858,6 +917,14 @@ pub fn run(settings: &Settings, state: &mut State, first_run: &mut bool) -> io:: | |||
| )) | |||
| } | |||
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| // Spawn `docker events --format '{{json .}}'`. | |||
| fn docker_events_listener() -> io::Result<Child> { | |||
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Can you make this function return the ScopeGuard (or just leave it inlined as it was)? The concern is that this creates a runaway process that is easy to forget about.
| "--format", | ||
| "{{.ID}}\\t{{.Repository}}\\t{{.Tag}}\\t{{.CreatedAt}}", | ||
| "{{range .Images}}{{.ID}}\\t{{.Repository}}\\t\ | ||
| {{.Tag}}\\t{{.CreatedAt}}\\t{{.UniqueSize}}\n{{end}}", |
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Is there a reason to double escape the tabs but only single escape the line break?
| match image_records.entry(id.to_owned()) { | ||
| // The id is in the format: | ||
| // sha256:745895703263072416be27b333d19eff4494b287001f6c6adddd22b963a3429d | ||
| // We only want the first 12 characters of the hash. |
| // The id is in the format: | ||
| // sha256:745895703263072416be27b333d19eff4494b287001f6c6adddd22b963a3429d | ||
| // We only want the first 12 characters of the hash. | ||
| let id = sha256_id.get(7..19).unwrap(); |
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Repository convention: all unwraps should be justified with a comment (even if obvious).
| } | ||
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| let new_space = space_usage()?; |
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So this is using a different mechanism to calculate the space usage than the loop that computes images_to_delete. I'm a bit concerned about what happens if these different methodologies disagree.
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(Closing old PRs due to inactivity.) |
When invoked, Docuum will report what images would have been deleted during it's initial vacuuming run at start up then exit.
In order to do this, Docuum now creates a list of images to delete ensuring that by deleting them it will meet the space requirements set forth by the user.
Fixes: #242