From be8864775227f6543a9cb00b36abb66bf26362f0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=BA=AA=E5=8D=93=E5=BF=97?= <jizhuozhi.george@gmail.com>
Date: Wed, 28 Jun 2023 09:42:19 +0800
Subject: [PATCH] feat: extract boilerplate code of `on_configure` to function
 (DRY) (#396)

---
 .../wasm-rust/extensions/say-hello/src/lib.rs | 33 ++++------------
 plugins/wasm-rust/src/rule_matcher.rs         | 38 +++++++++++++++----
 2 files changed, 39 insertions(+), 32 deletions(-)

diff --git a/plugins/wasm-rust/extensions/say-hello/src/lib.rs b/plugins/wasm-rust/extensions/say-hello/src/lib.rs
index 7c6302c6b..458a7a466 100644
--- a/plugins/wasm-rust/extensions/say-hello/src/lib.rs
+++ b/plugins/wasm-rust/extensions/say-hello/src/lib.rs
@@ -13,12 +13,12 @@
 // limitations under the License.
 
 use higress_wasm_rust::log::Log;
-use higress_wasm_rust::rule_matcher::RuleMatcher;
+use higress_wasm_rust::rule_matcher::{on_configure, RuleMatcher};
 use proxy_wasm::traits::{Context, HttpContext, RootContext};
 use proxy_wasm::types::{Action, ContextType, LogLevel};
 use serde::Deserialize;
-use serde_json::{from_slice, Value};
 use std::cell::RefCell;
+use std::ops::DerefMut;
 use std::rc::Rc;
 
 proxy_wasm::main! {{
@@ -53,29 +53,12 @@ impl Context for SayHelloRoot {}
 
 impl RootContext for SayHelloRoot {
     fn on_configure(&mut self, _plugin_configuration_size: usize) -> bool {
-        let config_buffer = match self.get_plugin_configuration() {
-            None => {
-                self.log
-                    .error("Error when configuring RootContext, no configuration supplied");
-                return false;
-            }
-            Some(bytes) => bytes,
-        };
-
-        let value = match from_slice::<Value>(config_buffer.as_slice()) {
-            Err(error) => {
-                self.log.error(
-                    format!("cannot parse plugin configuration JSON string: {}", error).as_str(),
-                );
-                return false;
-            }
-            Ok(value) => value,
-        };
-
-        self.rule_matcher
-            .borrow_mut()
-            .parse_rule_config(&value)
-            .is_ok()
+        on_configure(
+            self,
+            _plugin_configuration_size,
+            self.rule_matcher.borrow_mut().deref_mut(),
+            &self.log,
+        )
     }
 
     fn create_http_context(&self, _context_id: u32) -> Option<Box<dyn HttpContext>> {
diff --git a/plugins/wasm-rust/src/rule_matcher.rs b/plugins/wasm-rust/src/rule_matcher.rs
index b8de27662..10a874dd2 100644
--- a/plugins/wasm-rust/src/rule_matcher.rs
+++ b/plugins/wasm-rust/src/rule_matcher.rs
@@ -14,11 +14,13 @@
 
 use crate::error::WasmRustError;
 use crate::internal::{get_http_request_header, get_property};
+use crate::log::Log;
 use proxy_wasm::hostcalls::log;
+use proxy_wasm::traits::RootContext;
 use proxy_wasm::types::LogLevel;
-use serde_json::{Map, Value};
-use std::collections::HashSet;
 use serde::de::DeserializeOwned;
+use serde_json::{from_slice, Map, Value};
+use std::collections::HashSet;
 
 enum Category {
     Route,
@@ -55,12 +57,9 @@ pub struct RuleMatcher<PluginConfig> {
 
 impl<PluginConfig> RuleMatcher<PluginConfig>
 where
-    PluginConfig: Default+DeserializeOwned,
+    PluginConfig: Default + DeserializeOwned,
 {
-    pub fn parse_rule_config(
-        &mut self,
-        config: &Value,
-    ) -> Result<(), WasmRustError> {
+    pub fn parse_rule_config(&mut self, config: &Value) -> Result<(), WasmRustError> {
         let empty_object = Map::new();
         let empty_vec = Vec::new();
 
@@ -216,3 +215,28 @@ where
         false
     }
 }
+
+pub fn on_configure<RC: RootContext, PluginConfig: Default + DeserializeOwned>(
+    root_context: &RC,
+    _plugin_configuration_size: usize,
+    rule_matcher: &mut RuleMatcher<PluginConfig>,
+    log: &Log,
+) -> bool {
+    let config_buffer = match root_context.get_plugin_configuration() {
+        None => {
+            log.error("Error when configuring RootContext, no configuration supplied");
+            return false;
+        }
+        Some(bytes) => bytes,
+    };
+
+    let value = match from_slice::<Value>(config_buffer.as_slice()) {
+        Err(error) => {
+            log.error(format!("cannot parse plugin configuration JSON string: {}", error).as_str());
+            return false;
+        }
+        Ok(value) => value,
+    };
+
+    rule_matcher.parse_rule_config(&value).is_ok()
+}