From c73dca05857d171447625d1f2826055f965e75af Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Fri, 5 Jul 2024 16:57:45 +0200
Subject: [PATCH] Support new flexible YAML settings file format.

---
 libs/httpcl/include/httpcl/http-settings.hpp | 10 +-
 libs/httpcl/src/http-settings.cpp            | 98 ++++++++++++++++----
 2 files changed, 88 insertions(+), 20 deletions(-)

diff --git a/libs/httpcl/include/httpcl/http-settings.hpp b/libs/httpcl/include/httpcl/http-settings.hpp
index f62a0e5..125a3d6 100644
--- a/libs/httpcl/include/httpcl/http-settings.hpp
+++ b/libs/httpcl/include/httpcl/http-settings.hpp
@@ -5,6 +5,7 @@
 #include <map>
 #include <vector>
 #include <string>
+#include "yaml-cpp/yaml.h"
 
 
 namespace httpcl
@@ -41,6 +42,10 @@ struct Config
         std::string keychain;
     };
 
+    std::optional<std::string> scope;
+    std::regex urlPattern;
+    std::string urlPatternString;
+
     std::map<std::string, std::string> cookies;
     std::optional<BasicAuthentication> auth;
     std::optional<Proxy> proxy;
@@ -67,7 +72,7 @@ struct Config
 };
 
 /**
- * Loads settings from HTTP_SETTINGS_FILE.
+ * Loads/stores settings from/to HTTP_SETTINGS_FILE.
  * Allows returning config for a specific URL.
  */
 struct Settings
@@ -85,7 +90,8 @@ struct Settings
     /**
      * Map from URL pattern to some config values.
      */
-    std::map<std::string, Config> settings;
+    std::vector<Config> settings;
+    YAML::Node document;
 };
 
 struct secret
diff --git a/libs/httpcl/src/http-settings.cpp b/libs/httpcl/src/http-settings.cpp
index 71dfc97..4540ddd 100644
--- a/libs/httpcl/src/http-settings.cpp
+++ b/libs/httpcl/src/http-settings.cpp
@@ -112,9 +112,51 @@ struct convert<Config::Proxy>
 }
 
 namespace {
-YAML::Node configToNode(Config const& config, std::string const& url=".*") {
+
+std::string convertToRegex(const std::string& scope) {
+    std::string regexPattern = "^";
+    for (char c : scope) {
+        switch (c) {
+        case '*':
+            regexPattern += ".*";
+            break;
+        case '.':
+            regexPattern += "\\.";
+            break;
+        case '\\':
+            regexPattern += "\\\\";
+            break;
+        case '^':
+        case '$':
+        case '|':
+        case '(':
+        case ')':
+        case '[':
+        case ']':
+        case '{':
+        case '}':
+        case '?':
+        case '+':
+        case '-':
+        case '!':
+            regexPattern += '\\';
+            regexPattern += c;
+            break;
+        default:
+            regexPattern += c;
+            break;
+        }
+    }
+    regexPattern += ".*$";
+    return regexPattern;
+}
+
+YAML::Node configToNode(Config const& config) {
     YAML::Node result;
-    result["url"] = url;
+    if (config.scope)
+        result["scope"] = *config.scope;
+    else
+        result["url"] = config.urlPatternString;
 
     if (!config.cookies.empty())
         result["cookies"] = config.cookies;
@@ -139,16 +181,21 @@ YAML::Node configToNode(Config const& config, std::string const& url=".*") {
     return result;
 }
 
-std::pair<Config, std::string> configFromNode(YAML::Node const& node)
+Config configFromNode(YAML::Node const& node)
 {
-    std::string urlPattern;
     Config conf;
 
-    if (auto entryParam = node["url"])
-        urlPattern = entryParam.as<std::string>();
-    else
-        throw std::runtime_error(
-            "HTTP Settings: Missing 'url' field in: " + YAML::Dump(node));
+    if (auto entryParam = node["url"]) {
+        conf.urlPattern = conf.urlPatternString = entryParam.as<std::string>();
+    }
+    else {
+        if (auto entryParamScope = node["scope"])
+            conf.scope = entryParamScope.as<std::string>();
+        else
+            conf.scope = "*";
+        conf.urlPatternString = convertToRegex(*conf.scope);
+        conf.urlPattern = conf.urlPatternString;
+    }
 
     if (auto cookies = node["cookies"])
         conf.cookies = cookies.as<std::map<std::string, std::string>>();
@@ -172,7 +219,7 @@ std::pair<Config, std::string> configFromNode(YAML::Node const& node)
     if (auto apiKey = node["api-key"])
         conf.apiKey = apiKey.as<std::string>();
 
-    return {std::move(conf), std::move(urlPattern)};
+    return conf;
 }
 }
 
@@ -302,12 +349,20 @@ void Settings::load()
 
     try {
         log().debug("Loading HTTP settings from '{}'...", cookieJar);
-        auto node = YAML::LoadFile(cookieJar);
+        document = YAML::LoadFile(cookieJar);
+        YAML::Node httpSettingsNode;
         uint32_t idx = 0;
 
-        for (auto const& entry : node.as<std::vector<YAML::Node>>()) {
-            auto [conf, urlPattern] = configFromNode(entry);
-            settings[urlPattern] = std::move(conf);
+        if (document.IsMap()) {
+            httpSettingsNode = document["http-settings"];
+        }
+        else {
+            // Keep supporting the old format, where the root structure is a settings array.
+            httpSettingsNode = document;
+        }
+
+        for (auto const& entry : httpSettingsNode.as<std::vector<YAML::Node>>()) {
+            settings.emplace_back(configFromNode(entry));
             ++idx;
         }
 
@@ -330,9 +385,16 @@ void Settings::store()
     try {
         auto node = YAML::Node();
 
-        for (const auto& [key, config] : settings)
+        for (const auto& config : settings)
             node.push_back(configToNode(config));
 
+        if (document && document.IsMap()) {
+            document["http-settings"] = node;
+        }
+        else {
+            document = node;
+        }
+
         log().debug("Saving HTTP settings to '{}'...", cookieJar);
         std::ofstream os(cookieJar);
         os << node;
@@ -345,16 +407,16 @@ void Settings::store()
 Config::Config(const std::string& yamlConf)
 {
     YAML::Node parsedYaml = YAML::Load(yamlConf);
-    *this = configFromNode(parsedYaml).first;
+    *this = configFromNode(parsedYaml);
 }
 
 Config Settings::operator[] (const std::string &url) const
 {
     Config result;
 
-    for (auto const& [pattern, config] : settings)
+    for (auto const& config : settings)
     {
-        if (!std::regex_match(url, std::regex(pattern)))
+        if (!std::regex_match(url, config.urlPattern))
             continue;
         result |= config;
     }