Add dependency check to Makefile

DEVELOPMENT.md

@@ -1,16 +1,10 @@
 # Development
+**Check Dependencies**: Use the `make check_dependencies` command to ensure that all necessary commands are available for generation.
 
-`make generate` uses `generate.jsonnet` to create Jsonnet libraries for each version in
-`gen/<version>/`, it also creates `gen/grafonnet-latest/` which refers to the newest
-version. These Jsonnet libraries depend on the JSON Schemas from Grok and `grafonnet-base/`.
+**Generate Jsonnet Libraries**: The `make generate` command uses `generate.jsonnet` to generate Jsonnet libraries for each version found in `gen/<version>/`. It also produces `gen/grafonnet-latest/` referring to the latest version. These libraries are dependent on the JSON schemas from Grok and the `grafonnet-base/`.
 
-`make libdocs` will generate the docs for every version in `gen/<version>/` and `make
-latestdocs` will generate the docs in `docs/` for the `gen/grafonnet-latest/`. `make docs`
-combines them.
+**Generate Library Documentation**: By running `make libdocs`, you can produce documentation for every version in `gen/<version>/`. To create documentation for the `gen/grafonnet-latest/` you can use the `make latestdocs` command, which outputs documentation to `docs/`. Use `make docs` to combine these generated documents.
 
-The `grafonnet-base/` library provides the logic to convert JSON Schemas to a runtime
-library and adds veneer on top. The veneer is a thin layer on top of the raw library to
-improve the user experience.
+**Grafonnet-base Library**: The `grafonnet-base/` library forms the basis for converting JSON schemas into a compiled library, additionally providing an overlay for improved user experience.
 
-In `examples/` there are few example dashboard configurations that serve as inspiration as
-well as an experimentation playground for library features.
+**Examples**: The `examples/` directory contains several example dashboard configurations, which can be used both for inspiration and as a testing ground for library features.

Makefile

@@ -2,6 +2,9 @@
 
 LATEST := v10.0.0
 
+check_dependencies:
+	./scripts/dependancy_check.sh
+
 generate:
 	./scripts/generate.sh v10.0.0
 	./scripts/generate_latest.sh v10.0.0

scripts/dependancy_check.sh

@@ -0,0 +1,54 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+MIN_BASH_VERSION=4
+REQUIRED_COMMANDS=(
+  "mapfile"
+  "jb"
+  "jsonnet"
+  "jsonnetfmt"
+  "jrsonnet"
+  )
+
+function check_command_availability () {
+  if ! command -v "${1}" >/dev/null 2>&1; then
+    echo "Warning: $1 could not be found."
+    exit 1
+  else
+    echo "$1 found. Carry on."
+  fi
+}
+
+bash_version_check () {
+  local bash_version="${BASH_VERSINFO[0]:-0}"
+
+  if ((bash_version < MIN_BASH_VERSION)); then
+    echo "Warning: bash version ${bash_version} found. A minimum bash version of ${MIN_BASH_VERSION} is required."
+    return 1
+  else
+    echo "Bash version ${bash_version} is sufficient. Carry on."
+  fi
+}
+
+required_commands_availability_check () {
+  for cmd in "${REQUIRED_COMMANDS[@]}"
+  do
+    if  command -v $cmd >/dev/null 2>&1
+    then
+      echo "$cmd found. Carry on."
+    else
+      echo "Warning: $cmd could not be found."
+      exit 1
+    fi
+  done
+}
+
+check_dependencies () {
+  bash_version_check || exit 1
+
+  for cmd in "${REQUIRED_COMMANDS[@]}"; do
+    check_command_availability "$cmd" || exit 1
+  done
+}
+
+check_dependencies