Verify dependencies for fetch_input are available

1 files changed, 17 insertions, 0 deletions

diff --git a/bin/fetch_input.sh b/bin/fetch_input.sh
index 6b27931..d3a96ec 100755
--- a/bin/fetch_input.sh
+++ b/bin/fetch_input.sh
@@ -1,4 +1,5 @@
 #!/bin/sh -eu
+# vim: sw=2 et
 
 COOKIES="${HOME}/.adventofcode.json"
 
@@ -11,6 +12,20 @@ MODE="wget"
 # https://stackoverflow.com/q/21919156/how-do-i-copy-cookies-from-chrome
 SESSION=$(jq < "${COOKIES}" '."session-cookie"')
 
+check_dependency_availability() {
+  local bin
+
+  for bin in 'elinks' \
+    'jq' \
+    'wget'
+  do
+    if ! which "${bin}" >/dev/null; then
+      echo "Missing dependency: ${bin}" >&2
+      exit 1
+    fi
+  done
+}
+
 concat() {
   local part
 
@@ -26,6 +41,8 @@ authenticated_wget() {
       "${@}"
 }
 
+check_dependency_availability
+
 if [ "${MODE}" = 'wget' ]; then
   cd "${YEAR}"
   cd 'rust'