fix: use trailing slash on multi-source COPY destinations#48
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MatthewJamisonJS wants to merge 1 commit intoref-tools:mainfrom
Open
fix: use trailing slash on multi-source COPY destinations#48MatthewJamisonJS wants to merge 1 commit intoref-tools:mainfrom
MatthewJamisonJS wants to merge 1 commit intoref-tools:mainfrom
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Modern Docker builders (BuildKit, default since Docker 23) reject
multi-source COPY instructions whose destination does not end with a
slash, per the Dockerfile reference: "If multiple <src> resources are
specified ... then <dest> must be a directory, and it must end with a
slash /."
Building this image with default Docker fails at:
Step 3/14 : COPY package.json package-lock.json tsconfig.json .
When using COPY with more than one source file, the destination
must be a directory and end with a /
Fix the two affected lines (lines 8 and 18) by changing the
destination from "." to "./". Single-source COPY instructions are
unchanged because Docker resolves them against the WORKDIR directly.
Build verified locally with Docker 28.5.1.
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docker buildfails on current Docker (BuildKit, default since Docker 23) because twoCOPYlines use.as the destination with multiple sources:The Dockerfile reference requires a trailing
/for multi-source copies. Changing.→./on the two affected lines fixes the build.Single-source
COPYlines are untouched.Verified locally on Docker 28.5.1 — build completes and
docker run -e REF_API_KEY=test ...starts as expected. Independent of #47 (different lines); built both layered together too with no conflict.