subsystem: cli

Add kata command line bash completion

Fixes #110

Signed-off-by: Ricardo Aravena <raravena@branch.io>

Makefile

@@ -78,6 +78,9 @@ GENERATED_FILES += $(COLLECT_SCRIPT)
 SCRIPTS += $(COLLECT_SCRIPT)
 SCRIPTS_DIR := $(BINDIR)
 
+BASH_COMPLETIONS := data/completions/bash/kata-runtime
+BASH_COMPLETIONSDIR := $(SHAREDIR)/bash-completion/completions
+
 PKGDATADIR := $(SHAREDIR)/$(PROJECT_DIR)
 PKGLIBDIR := $(LOCALSTATEDIR)/lib/$(PROJECT_DIR)
 PKGRUNDIR := $(LOCALSTATEDIR)/run/$(PROJECT_DIR)
@@ -389,13 +392,16 @@ check-go-static:
 coverage:
 	$(QUIET_TEST).ci/go-test.sh html-coverage
 
-install: default runtime install-scripts
+install: default runtime install-scripts install-completions
 	$(QUIET_INST)install -D $(TARGET) $(DESTTARGET)
 	$(QUIET_INST)install -D $(CONFIG) $(DESTCONFIG)
 
 install-scripts: $(SCRIPTS)
 	$(foreach f,$(SCRIPTS),$(call INSTALL_EXEC,$f,$(SCRIPTS_DIR)))
 
+install-completions:
+	$(QUIET_INST)install --mode 0644 -D $(BASH_COMPLETIONS) $(BASH_COMPLETIONSDIR)
+
 clean:
 	$(QUIET_CLEAN)rm -f $(TARGET) $(CONFIG) $(GENERATED_GO_FILES) $(GENERATED_FILES) $(COLLECT_SCRIPT)
 

data/completions/bash/kata-runtime

@@ -0,0 +1,138 @@
+#!/bin/bash
+#
+# Copyright (c) 2018 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+#---------------------------------------------------------------------
+# Description: Bash tab completion script.
+#---------------------------------------------------------------------
+
+_kataruntime='kata-runtime'
+
+# Return a list of sub-commands
+_kata_get_subcmds()
+{
+    "$_kataruntime" --generate-bash-completion
+}
+
+# Return a list of options for the specified sub-command
+#
+# Limitation: Note that this only supports long-options.
+_kata_get_subcmd_options()
+{
+    local subcmd="$1"
+
+    "$_kataruntime" "$subcmd" --help |\
+        egrep -- "^ *--[^ ]*[ ][^ ]*" |\
+        awk '{print $1}' |\
+        tr -d \, |\
+        sort
+}
+
+# Return a list of global options
+_kata_get_global_options()
+{
+    _kata_get_subcmd_options ""
+}
+
+# Return name of subcmd already seen, or ""
+_kata_subcmd_seen()
+{
+    local subcmds=$(_kata_get_subcmds)
+    local cmd
+
+    for cmd in $subcmds; do
+        local word
+        for word in ${COMP_WORDS[@]}; do
+            [ "$cmd" = "$word" ] && echo "$cmd"
+        done
+    done
+
+    echo ""
+}
+
+# Return 0 if the specified sub-command requires the name of an
+# *existing* container, else 1.
+_kata_subcmd_needs_existing_container()
+{
+    local subcmd="$1"
+    local cmd
+
+    for cmd in \
+	    'kata-check' \
+	    'kata-env' \
+	    'create' \
+	    'help' \
+	    'list' \
+	    'version'; do
+        [ "$cmd" = "$subcmd" ] && return 1
+    done
+
+    return 0
+}
+
+# Returns a list of container names
+_kata_get_containers()
+{
+    # Commands that manipulate containers need root privileges.
+    # If the user isn't running as root, don't attempt to obtain a list
+    # as it will result in an error.
+    [ $(id -u) -eq 0 ] || return
+
+    "$_kataruntime" list --quiet
+}
+
+_kata_bash_autocomplete() {
+    COMPREPLY=()
+
+    local opts opt
+
+    local cur="${COMP_WORDS[COMP_CWORD]}"
+
+    for opt in \
+        '-h' '--help' 'help' \
+        '-v' '--version' 'version';
+    do
+        # No further completions possible for these commands
+        [ "$cur" = "$opt" ] && return 0
+    done
+
+    local subcmd_seen=$(_kata_subcmd_seen)
+
+    if [ -n "$subcmd_seen" ]; then
+	    _kata_subcmd_needs_existing_container "$subcmd_seen"
+	    local container_cmd=$?
+
+            if [ -n "$cur" ]; then
+                    # Complete with local options and maybe container names
+                    opts=$(_kata_get_subcmd_options "$subcmd_seen")
+                    [ $container_cmd -eq 0 ] && opts="$opts $(_kata_get_containers)"
+            elif [[ "${cur}" == -* ]]; then
+                    # Complete with local options
+                    opts=$(_kata_get_subcmd_options "$subcmd_seen")
+            else
+                    # Potentially complete with container names
+                    [ $container_cmd -eq 0 ] && opts="$(_kata_get_containers)"
+            fi
+    else
+            if [ -n "$cur" ]; then
+                    # Complete with global options and subcmds
+                    opts="$opts $(_kata_get_global_options)"
+                    opts="$opts $(_kata_get_subcmds)"
+            elif [[ "${cur}" == -* ]]; then
+                    # Complete with global options
+                    opts=$(_kata_get_global_options)
+            else
+                    # Complete with subcmds
+                    opts=$(_kata_get_subcmds)
+            fi
+    fi
+
+    [ -n "$opts" ] && COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
+
+    return 0
+}
+
+complete -F _kata_bash_autocomplete "$_kataruntime"