simplified logging in provider and simplified Result type handling

mochi-hpc · Sep 26, 2023 · 4e57d2d · 4e57d2d
1 parent b6889b1
commit 4e57d2d
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Showing 9 changed files with 214 additions and 143 deletions.
diff --git a/examples/client.cpp b/examples/client.cpp
@@ -35,8 +35,6 @@ int main(int argc, char** argv) {
             client.makeResourceHandle(g_address, g_provider_id,
                     alpha::UUID::from_string(g_resource.c_str()));
 
-        resource.sayHello();
-
         int32_t result;
         resource.computeSum(32, 54, &result);
 

diff --git a/include/alpha/ResourceHandle.hpp b/include/alpha/ResourceHandle.hpp
@@ -72,11 +72,6 @@ class ResourceHandle {
      */
     operator bool() const;
 
-    /**
-     * @brief Sends an RPC to the resource to make it print a hello message.
-     */
-    void sayHello() const;
-
     /**
      * @brief Requests the target resource to compute the sum of two numbers.
      * If result is null, it will be ignored. If req is not null, this call

diff --git a/include/alpha/Result.hpp b/include/alpha/Result.hpp
@@ -6,6 +6,7 @@
 #ifndef __ALPHA_RESULT_HPP
 #define __ALPHA_RESULT_HPP
 
+#include <alpha/Exception.hpp>
 #include <string>
 
 namespace alpha {
@@ -79,6 +80,53 @@ class Result {
         return m_value;
     }
 
+    /**
+     * @brief Value if the request succeeded,
+     * throws otherwise.
+     */
+    const T& valueOrThrow() const & {
+        check();
+        return m_value;
+    }
+
+    /**
+     * @brief Value if the request succeeded,
+     * throws otherwise.
+     */
+    T&& valueOrThrow() && {
+        check();
+        return std::move(m_value);
+    }
+
+    /**
+     * @brief Execute a function on the value
+     * if the value is present, otherwise throws
+     * an Exception.
+     */
+    template<typename F>
+    decltype(auto) andThen(F&& f) const & {
+        return std::forward<F>(f)(valueOrThrow());
+    }
+
+    /**
+     * @brief Execute a function on the value
+     * if the value is present, otherwise throws
+     * an Exception.
+     */
+    template<typename F>
+    decltype(auto) andThen(F&& f) && {
+        return std::forward<F>(f)(valueOrThrow());
+    }
+
+    /**
+     * @brief Throw an Exception if the Result
+     * contains an error.
+     */
+    void check() const {
+        if(!m_success)
+            throw Exception(m_error);
+    }
+
     /**
      * @brief Serialization function for Thallium.
      *
@@ -88,8 +136,11 @@ class Result {
     template<typename Archive>
     void serialize(Archive& a) {
         a & m_success;
-        a & m_error;
-        a & m_value;
+        if(m_success) {
+            a & m_value;
+        } else {
+            a & m_error;
+        }
     }
 
     private:
@@ -134,6 +185,31 @@ class Result<std::string> {
         return m_content;
     }
 
+    const std::string& valueOrThrow() const & {
+        check();
+        return m_content;
+    }
+
+    std::string&& valueOrThrow() && {
+        check();
+        return std::move(m_content);
+    }
+
+    template<typename F>
+    decltype(auto) andThen(F&& f) const & {
+        return std::forward<F>(f)(valueOrThrow());
+    }
+
+    template<typename F>
+    decltype(auto) andThen(F&& f) && {
+        return std::forward<F>(f)(valueOrThrow());
+    }
+
+    void check() const {
+        if(!m_success)
+            throw Exception(m_content);
+    }
+
     template<typename Archive>
     void serialize(Archive& a) {
         a & m_success;
@@ -181,10 +257,27 @@ class Result<bool> {
         return m_success;
     }
 
+    bool valueOrThrow() const {
+        check();
+        return true;
+    }
+
+    template<typename F>
+    decltype(auto) andThen(F&& f) const {
+        check();
+        return std::forward<F>(f)();
+    }
+
+    void check() const {
+        if(!m_success)
+            throw Exception(m_error);
+    }
+
     template<typename Archive>
     void serialize(Archive& a) {
         a & m_success;
-        a & m_error;
+        if(!m_success)
+            a & m_error;
     }
 
     private:

diff --git a/src/Admin.cpp b/src/Admin.cpp
@@ -46,10 +46,7 @@ UUID Admin::createResource(const std::string& address,
     auto endpoint  = self->m_engine.lookup(address);
     auto ph        = tl::provider_handle(endpoint, provider_id);
     Result<UUID> result = self->m_create_resource.on(ph)(token, resource_type, resource_config);
-    if(not result.success()) {
-        throw Exception(result.error());
-    }
-    return result.value();
+    return std::move(result).valueOrThrow();
 }
 
 UUID Admin::openResource(const std::string& address,
@@ -60,10 +57,7 @@ UUID Admin::openResource(const std::string& address,
     auto endpoint  = self->m_engine.lookup(address);
     auto ph        = tl::provider_handle(endpoint, provider_id);
     Result<UUID> result = self->m_open_resource.on(ph)(token, resource_type, resource_config);
-    if(not result.success()) {
-        throw Exception(result.error());
-    }
-    return result.value();
+    return std::move(result).valueOrThrow();
 }
 
 void Admin::closeResource(const std::string& address,
@@ -73,9 +67,7 @@ void Admin::closeResource(const std::string& address,
     auto endpoint  = self->m_engine.lookup(address);
     auto ph        = tl::provider_handle(endpoint, provider_id);
     Result<bool> result = self->m_close_resource.on(ph)(token, resource_id);
-    if(not result.success()) {
-        throw Exception(result.error());
-    }
+    result.check();
 }
 
 void Admin::destroyResource(const std::string& address,
@@ -85,9 +77,7 @@ void Admin::destroyResource(const std::string& address,
     auto endpoint  = self->m_engine.lookup(address);
     auto ph        = tl::provider_handle(endpoint, provider_id);
     Result<bool> result = self->m_destroy_resource.on(ph)(token, resource_id);
-    if(not result.success()) {
-        throw Exception(result.error());
-    }
+    result.check();
 }
 
 void Admin::shutdownServer(const std::string& address) const {

diff --git a/src/Client.cpp b/src/Client.cpp
@@ -55,17 +55,13 @@ ResourceHandle Client::makeResourceHandle(
     auto endpoint  = self->m_engine.lookup(address);
     auto ph        = tl::provider_handle(endpoint, provider_id);
     Result<bool> result;
-    result.success() = true;
     if(check) {
         result = self->m_check_resource.on(ph)(resource_id);
     }
-    if(result.success()) {
+    return result.andThen([&]() {
         auto resource_impl = std::make_shared<ResourceHandleImpl>(self, std::move(ph), resource_id);
         return ResourceHandle(resource_impl);
-    } else {
-        throw Exception(result.error());
-        return ResourceHandle(nullptr);
-    }
+    });
 }
 
 std::string Client::getConfig() const {

diff --git a/src/ClientImpl.hpp b/src/ClientImpl.hpp
@@ -21,13 +21,11 @@ class ClientImpl {
 
     tl::engine           m_engine;
     tl::remote_procedure m_check_resource;
-    tl::remote_procedure m_say_hello;
     tl::remote_procedure m_compute_sum;
 
     ClientImpl(const tl::engine& engine)
     : m_engine(engine)
     , m_check_resource(m_engine.define("alpha_check_resource"))
-    , m_say_hello(m_engine.define("alpha_say_hello").disable_response())
     , m_compute_sum(m_engine.define("alpha_compute_sum"))
     {}