first version

Dockerfile

@@ -0,0 +1,9 @@
+FROM alpine:latest
+
+RUN	apk add --no-cache \
+  curl \
+  jq
+
+COPY fetch_github_asset.sh /fetch_github_asset.sh
+
+ENTRYPOINT ["/fetch_github_asset.sh"]

README.md

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-# fetch-gh-release-asset
-Github Action to download an asset from a Github release
+# Fetch GH Release Asset
+
+This action downloads an asset from a Github release. Private repos are supported.
+
+## Inputs
+
+### `repo`
+
+**Required** The `org/repo`.
+
+### `version`
+
+The release version to fetch from. Default `"latest"`.
+
+### `file`
+
+**Required** The name of the file in the release.
+
+## Example usage
+
+```yaml
+uses: dsaltares/fetch-gh-release-asset@master
+with:
+  repo: "dsaltares/godot-wild-jam-18"
+  version: "latest"
+  file: "plague-linux.zip"
+```

action.yaml

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+name: 'Fetch Github Release Asset'
+description: 'Downloads an asset from a Github release'
+
+inputs:
+  repo:
+    description: 'org/repo to download from'
+    required: true
+  version:
+    description: 'version of the release to download from'
+    required: false
+    default: 'latest'
+  file:
+    description: 'name of the file in the release to download'
+    required: true
+
+runs:
+  using: 'docker'
+  image: 'Dockerfile'
+  args:
+    - ${{ inputs.repo }}
+    - ${{ inputs.version }}
+    - ${{ inputs.file }}
+
+branding:
+  icon: 'download-cloud'
+  color: 'orange'

fetch_github_asset.sh

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+#!/bin/bash
+
+if [[ -z "$GITHUB_TOKEN" ]]; then
+  echo "Missing GITHUB_TOKEN env variable"
+  exit 1
+fi
+
+if [[ -z "$INPUT_REPO" ]]; then
+  echo "Missing repo input in the action"
+  exit 1
+fi
+
+if [[ -z "$INPUT_FILE" ]]; then
+  echo "Missing file input in the action"
+  exit 1
+fi
+
+API_URL="https://$GITHUB_TOKEN:@api.github.com/repos/$INPUT_REPO"
+ASSET_ID=$(curl $API_URL/releases/${INPUT_VERSION} | jq -r ".assets | map(select(.name == \"${INPUT_FILE}\"))[0].id")
+
+if [[ -z "$ASSET_ID" ]]; then
+  echo "Could not find asset id"
+  exit 1
+fi
+
+curl \
+  -J \
+  -L \
+  -H "Accept: application/octet-stream" \
+  "$API_URL/releases/assets/$ASSET_ID" \
+  -o ${INPUT_FILE}