feat(ci): gha and blacksmith for prs (#4647)

.github/workflows/scripts/common.sh

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+set -eo pipefail
+
+# shellcheck disable=SC2034
+DOCKER_IMAGE_TAG="speckle/speckle-${SPECKLE_SERVER_PACKAGE}"
+
+# shellcheck disable=SC2034,SC2086
+IMAGE_VERSION_TAG="${IMAGE_VERSION_TAG:-${GITHUB_SHA}}"
+
+# shellcheck disable=SC2068,SC2046
+LAST_RELEASE="$(git describe --always --tags $(git rev-list --tags) | grep -E '^[0-9]+\.[0-9]+\.[0-9]+$' | head -n 1)" # get the last release tag. FIXME: Fails if a commit is tagged with more than one tag: https://stackoverflow.com/questions/8089002/git-describe-with-two-tags-on-the-same-commit/56039163#56039163
+
+# shellcheck disable=SC2034
+NEXT_RELEASE="$(echo "${LAST_RELEASE}" | awk -F. -v OFS=. '{$NF += 1 ; print}')"
+
+# shellcheck disable=SC2034
+BRANCH_NAME_TRUNCATED="$(echo "${GITHUB_HEAD_REF}" | cut -c -50 | sed 's/[^a-zA-Z0-9.-]/-/g')" # docker has a 128 character tag limit, so ensuring the branch name will be short enough
+
+# shellcheck disable=SC2034
+COMMIT_SHA1_TRUNCATED="$(echo "${GITHUB_SHA}" | cut -c -7)"

.github/workflows/scripts/get_version.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+set -eo pipefail
+
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+# shellcheck disable=SC1090,SC1091
+source "${SCRIPT_DIR}/common.sh"
+
+
+if [[ "${GITHUB_REF}" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
+    echo "${GITHUB_REF}"
+    exit 0
+fi
+
+if [[ "${GITHUB_HEAD_REF}" == "main" ]]; then
+    echo "${NEXT_RELEASE}-alpha.${GITHUB_RUN_ID}"
+    exit 0
+fi
+
+# if branch name truncated contains an underscore, we should exit
+if [[ "${BRANCH_NAME_TRUNCATED}" =~ "_" ]]; then
+    echo "Branch name contains an underscore, exiting"
+    exit 1
+fi
+
+echo "${NEXT_RELEASE}-branch.${BRANCH_NAME_TRUNCATED}.${GITHUB_RUN_ID}-${COMMIT_SHA1_TRUNCATED}"
+exit 0