install go via script

.circleci/config.yml

@@ -212,7 +212,7 @@ jobs:
       - restore_cache:
           key: go-mod-v1-{{ checksum "go.sum" }}
       - check-changed-files-or-halt
-      - run: 'snap install go --classic'
+      - run: './scripts/installgo_linux.sh'
       - run: 'make deps'
       - run: 'make test-integration'
   test-go-mac:

scripts/installgo_linux.sh

@@ -0,0 +1,34 @@
+#!/bin/sh
+
+set -eux
+
+ARCH=$(uname -m)
+GO_VERSION="1.18.3"
+GO_ARCH="linux-amd64"
+# from https://golang.org/dl
+GO_VERSION_SHA="956f8507b302ab0bb747613695cdae10af99bbd39a90cae522b7c0302cc27245"
+
+setup_go () {
+    echo "installing go"
+    curl -L https://golang.org/dl/go${GO_VERSION}.${GO_ARCH}.tar.gz --output go${GO_VERSION}.${GO_ARCH}.tar.gz
+    if ! echo "${GO_VERSION_SHA}  go${GO_VERSION}.${GO_ARCH}.tar.gz" | shasum --algorithm 256 --check -; then
+        echo "Checksum failed" >&2
+        exit 1
+    fi
+
+    rm -rf /usr/local/go
+    tar -C /usr/local -xzf go${GO_VERSION}.${GO_ARCH}.tar.gz
+    sudo ln -sf /usr/local/go/bin/go /usr/local/bin/go
+}
+
+if command -v go >/dev/null 2>&1; then
+    echo "Go is already installed"
+    v=$(go version | { read -r _ _ v _; echo "${v#go}"; })
+    echo "$v is installed, required version is ${GO_VERSION}"
+    if [ "$v" != ${GO_VERSION} ]; then
+        setup_go
+        go version
+    fi
+else
+    setup_go
+fi