Add json schema

plugin/lsp_settings.vim

@@ -17,6 +17,8 @@ let s:servers_dir = expand('<sfile>:h:h').'/servers'
 let s:settings = json_decode(join(readfile(expand('<sfile>:h:h').'/settings.json'), "\n"))
 let s:ftmap = {}
 
+call remove(s:settings, '$schema')
+
 function! s:executable(cmd) abort
   if executable(a:cmd)
     return 1

schema.json

@@ -0,0 +1,56 @@
+{
+  "$schema": "http://json-schema.org/draft-04/schema",
+  "type": "object",
+  "title": "vim-lsp-settings",
+  "additionalProperties": false,
+  "patternProperties": {
+    "^\\$schema$": {
+      "type": "string"
+    },
+    "^([a-z0-9_-]+)+$": {
+      "type": "array",
+      "title": "filetype name",
+      "items": {
+        "title": "define command description",
+        "type": "object",
+        "additionalProperties": false,
+        "required": [
+          "command",
+          "requires"
+        ],
+        "properties": {
+          "command": {
+            "title": "define name of language server",
+            "type": "string"
+          },
+          "requires": {
+            "title": "define commands to install this language server",
+            "type": "array",
+            "items": {
+              "type": "string",
+              "title": "executable command name"
+            }
+          },
+          "vim-plugin": {
+            "title": "define suggestion for vim-plugin",
+            "type": "object",
+            "additionalProperties": false,
+            "properties": {
+              "extensions": {
+                "type": "array",
+                "items": {
+                  "type": "string",
+                  "title": "file extensions"
+                }
+              },
+              "name": {
+                "type": "string",
+                "title": "plugin identify user/repo"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

settings.json

@@ -1,4 +1,5 @@
 {
+  "$schema": "./schema.json",
   "c": [
     {
       "command": "clangd",