feat: add schema validate admin API

apisix/admin/init.lua

@@ -376,6 +376,41 @@ local function reload_plugins(data, event, source, pid)
 end
 
 
+local function schema_validate()
+    local uri_segs = core.utils.split_uri(ngx.var.uri)
+    core.log.info("uri: ", core.json.delay_encode(uri_segs))
+
+    local seg_res = uri_segs[6]
+    local resource = resources[seg_res]
+    if not resource then
+        core.response.exit(404, {error_msg = "Unsupported resource type: ".. seg_res})
+    end
+
+    local req_body, err = core.request.get_body(MAX_REQ_BODY)
+    if err then
+        core.log.error("failed to read request body: ", err)
+        core.response.exit(400, {error_msg = "invalid request body: " .. err})
+    end
+
+    if req_body then
+        local data, err = core.json.decode(req_body)
+        if err then
+            core.log.error("invalid request body: ", req_body, " err: ", err)
+            core.response.exit(400, {error_msg = "invalid request body: " .. err,
+                                     req_body = req_body})
+        end
+
+        req_body = data
+    end
+
+    local ok, err = core.schema.check(resource.schema, req_body)
+    if ok then
+        core.response.exit(200)
+    end
+    core.response.exit(400, {error_msg = err})
+end
+
+
 local uri_route = {
     {
         paths = [[/apisix/admin]],
@@ -392,6 +427,11 @@ local uri_route = {
         methods = {"GET"},
         handler = get_plugins_list,
     },
+    {
+        paths = [[/apisix/admin/schema/validate/*]],
+        methods = {"POST"},
+        handler = schema_validate,
+    },
     {
         paths = reload_event,
         methods = {"PUT"},

docs/en/latest/admin-api.md

@@ -1514,3 +1514,52 @@ Proto resource request address: /apisix/admin/protos/{id}
 | content   | True    | String | content of `.proto` or `.pb` files | See [here](./plugins/grpc-transcode.md#enabling-the-plugin)         |
 | create_time | False    | Epoch timestamp (in seconds) of the created time. If missing, this field will be populated automatically.             | 1602883670                                       |
 | update_time | False    | Epoch timestamp (in seconds) of the updated time. If missing, this field will be populated automatically.             | 1602883670                                       |
+
+## Schema validation
+
+Check the validity of a configuration against its entity schema. This allows you to test your input before submitting a request to the entity endpoints of the Admin API.
+
+Note that this only performs the schema validation checks, checking that the input configuration is well-formed. Requests to the entity endpoint using the given configuration may still fail due to other reasons, such as invalid foreign key relationships or uniqueness check failures against the contents of the data store.
+
+### Schema validation
+
+Schema validation request address: /apisix/admin/schema/validate/{resource}
+
+### Request Methods
+
+| Method | Request URI                      | Request Body | Description                                     |
+| ------ | -------------------------------- | ------------ | ----------------------------------------------- |
+| POST   | /apisix/admin/schema/validate/{resource}      | {..resource conf..}        | Validate the resource configuration against corresponding schema.         |
+
+### Request Body Parameters
+
+* 200: validate ok.
+* 400: validate failed, with error as response body in JSON format.
+
+Example:
+
+```bash
+curl http://127.0.0.1:9180/apisix/admin/schema/validate/routes \
+    -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X POST -i -d '{
+    "uri": 1980,
+    "upstream": {
+        "scheme": "https",
+        "type": "roundrobin",
+        "nodes": {
+            "nghttp2.org": 1
+        }
+    }
+}'
+HTTP/1.1 400 Bad Request
+Date: Mon, 21 Aug 2023 07:37:13 GMT
+Content-Type: application/json
+Transfer-Encoding: chunked
+Connection: keep-alive
+Server: APISIX/3.4.0
+Access-Control-Allow-Origin: *
+Access-Control-Allow-Credentials: true
+Access-Control-Expose-Headers: *
+Access-Control-Max-Age: 3600
+
+{"error_msg":"property \"uri\" validation failed: wrong type: expected string, got number"}
+```