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Merge pull request #17819 from peterhauke/patch-11

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Fix typos and make minor language edits
This commit is contained in:
David Karlsson
2023-07-31 11:09:48 +02:00
committed by GitHub
parent 2c62ba1121 764f75cf9b
commit d8d84eeb05
1 changed files with 6 additions and 6 deletions
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build/guide/layers.md
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@@ -6,7 +6,7 @@ keywords: build, buildkit, buildx, guide, tutorial, layers
{% include_relative nav.html selected="2" %}
The order of Dockerfile instructions matter. A Docker build consists of a series
The order of Dockerfile instructions matters. A Docker build consists of a series
of ordered build instructions. Each instruction in a Dockerfile roughly translates
to an image layer. The following diagram illustrates how a Dockerfile translates
into a stack of layers in a container image.
@@ -22,20 +22,20 @@ If a layer has changed since the last build, that layer, and all layers that fol
The Dockerfile from the previous section copies all project files to the
container (`COPY . .`) and then downloads application dependencies in the
following step (`RUN go mod download`). If you were to change any of the project
files, that would invalidate the cache for the `COPY` layer. It also invalidates
files, then that would invalidate the cache for the `COPY` layer. It also invalidates
the cache for all of the layers that follow.
![Layer cache is bust](./images/cache-bust.png){:.invertible}
The current order of the Dockerfile instruction make it so that the builder must
Because of the current order of the Dockerfile instructions, the builder must
download the Go modules again, despite none of the packages having changed since
last time.
the last time.
## Update the instruction order
You can avoid this redundancy by reordering the instructions in the Dockerfile.
Change the order of the instructions so that downloading and installing dependencies
occurs before you copy the source code over to the container. That way, the
occur before the source code is copied over to the container. In that way, the
builder can reuse the "dependencies" layer from the cache, even when you
make changes to your source code.
@@ -58,7 +58,7 @@ For Go to know which dependencies to download, you need to copy the `go.mod` and
ENTRYPOINT [ "/bin/server" ]
```
Now if you edit the application code, building the image won't cause the
Now if you edit your source code, building the image won't cause the
builder to download the dependencies each time. The `COPY . .` instruction
appears after the package management instructions, so the builder can reuse the
`RUN go mod download` layer.