feat: curl diagnostics (#46)

closes #45

---------

Co-authored-by: Jiacai Liu <dev@liujiacai.net>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: 3 people

README.org

@@ -38,7 +38,7 @@ pub fn main() !void {
 
     const ca_bundle = try curl.allocCABundle(allocator);
     defer ca_bundle.deinit();
-    const easy = try curl.Easy.init(.{
+    var easy = try curl.Easy.init(.{
         .ca_bundle = ca_bundle,
     });
     defer easy.deinit();

examples/advanced.zig

@@ -20,7 +20,7 @@ const Response = struct {
     url: []const u8,
 };
 
-fn putWithCustomHeader(allocator: Allocator, easy: Easy) !void {
+fn putWithCustomHeader(allocator: Allocator, easy: *Easy) !void {
     const body =
         \\ {"name": "John", "age": 15}
     ;
@@ -87,7 +87,7 @@ fn putWithCustomHeader(allocator: Allocator, easy: Easy) !void {
     }
 }
 
-fn postMultiPart(allocator: Allocator, easy: Easy) !void {
+fn postMultiPart(allocator: Allocator, easy: *Easy) !void {
     // Reset old options, e.g. headers.
     easy.reset();
 
@@ -118,10 +118,37 @@ pub fn main() !void {
 
     const ca_bundle = try curl.allocCABundle(allocator);
     defer ca_bundle.deinit();
-    const easy = try Easy.init(.{ .ca_bundle = ca_bundle });
+
+    var easy = try Easy.init(.{
+        .ca_bundle = ca_bundle,
+    });
     defer easy.deinit();
 
     println("PUT with custom header demo");
-    try putWithCustomHeader(allocator, easy);
-    try postMultiPart(allocator, easy);
+    putWithCustomHeader(allocator, &easy) catch |err| {
+        if (easy.diagnostics.error_code) |error_code| {
+            switch (error_code) {
+                .code => |c| {
+                    std.log.err("putWithCustomHeader encountered a curl error! error code: {}", .{c});
+                },
+                .m_code => |mc| {
+                    std.log.err("putWithCustomHeader encountered a curl multi error! error code: {}", .{mc});
+                },
+            }
+        }
+        return err;
+    };
+    postMultiPart(allocator, &easy) catch |err| {
+        if (easy.diagnostics.error_code) |error_code| {
+            switch (error_code) {
+                .code => |c| {
+                    std.log.err("postMultipart encountered a curl error! error code: {}", .{c});
+                },
+                .m_code => |mc| {
+                    std.log.err("postMultipart encountered a curl multi error! error code: {}", .{mc});
+                },
+            }
+        }
+        return err;
+    };
 }

examples/basic.zig

@@ -10,7 +10,7 @@ pub fn main() !void {
 
     const ca_bundle = try curl.allocCABundle(allocator);
     defer ca_bundle.deinit();
-    const easy = try curl.Easy.init(.{
+    var easy = try curl.Easy.init(.{
         .ca_bundle = ca_bundle,
     });
     defer easy.deinit();

examples/header.zig

@@ -3,7 +3,7 @@ const curl = @import("curl");
 const Easy = curl.Easy;
 const println = @import("util.zig").println;
 
-fn iterateHeaders(easy: Easy) !void {
+fn iterateHeaders(easy: *Easy) !void {
     // Reset old options, e.g. headers.
     easy.reset();
 
@@ -29,11 +29,12 @@ fn iterateHeaders(easy: Easy) !void {
     }
 }
 
-fn iterateRedirectedHeaders(easy: Easy) !void {
+fn iterateRedirectedHeaders(easy: *Easy) !void {
     try easy.setFollowLocation(true);
     const resp = try easy.fetch("https://edgebin.liujiacai.net/redirect/2", .{});
 
-    const redirects = try resp.getRedirectCount();
+    var diagnostics: Easy.Diagnostics = .{};
+    const redirects = try resp.getRedirectCount(&diagnostics);
     try std.testing.expectEqual(redirects, 2);
 
     for (0..redirects + 1) |i| {
@@ -64,7 +65,7 @@ pub fn main() !void {
 
     const ca_bundle = try curl.allocCABundle(allocator);
     defer ca_bundle.deinit();
-    const easy = try Easy.init(.{ .ca_bundle = ca_bundle });
+    var easy = try Easy.init(.{ .ca_bundle = ca_bundle });
     defer easy.deinit();
 
     if (comptime !curl.hasParseHeaderSupport()) {
@@ -73,11 +74,11 @@ pub fn main() !void {
     }
 
     println("Iterate headers demo");
-    try iterateHeaders(easy);
+    try iterateHeaders(&easy);
 
     // Reset old options, e.g. headers.
     easy.reset();
 
     println("Redirected headers demo");
-    try iterateRedirectedHeaders(easy);
+    try iterateRedirectedHeaders(&easy);
 }

examples/multi.zig

@@ -10,7 +10,7 @@ const checkCode = curl.checkCode;
 const Writer = std.io.Writer;
 
 fn newEasy(writer: *Writer, url: [:0]const u8) !Easy {
-    const easy = try Easy.init(.{});
+    var easy = try Easy.init(.{});
     try easy.setUrl(url);
     try easy.setWriter(writer);
     // CURLOPT_PRIVATE allows us to store a pointer to the ctx in the easy handle
@@ -25,16 +25,23 @@ pub fn main() !void {
     defer if (gpa.deinit() != .ok) @panic("leak");
     const allocator = gpa.allocator();
 
-    const multi = try Multi.init();
+    var diagnostics: Multi.Diagnostics = .{};
+
+    const multi = try Multi.init(&diagnostics);
     defer multi.deinit();
 
     var wtr1 = std.Io.Writer.Allocating.init(allocator);
     defer wtr1.deinit();
     var wtr2 = std.Io.Writer.Allocating.init(allocator);
     defer wtr2.deinit();
 
-    try multi.addHandle(try newEasy(&wtr1.writer, "http://edgebin.liujiacai.net/headers"));
-    try multi.addHandle(try newEasy(&wtr2.writer, "http://edgebin.liujiacai.net/ip"));
+    var easy1 = try newEasy(&wtr1.writer, "http://edgebin.liujiacai.net/headers");
+    defer easy1.deinit();
+    var easy2 = try newEasy(&wtr2.writer, "http://edgebin.liujiacai.net/ip");
+    defer easy2.deinit();
+
+    try multi.addHandle(&easy1);
+    try multi.addHandle(&easy2);
 
     var keep_running = true;
     while (keep_running) {
@@ -60,16 +67,16 @@ pub fn main() !void {
         }
 
         // check that the request was successful
-        try checkCode(info.msg.data.result);
+        try checkCode(info.msg.data.result, &diagnostics);
 
         // Read the HTTP status code
         var status_code: c_long = 0;
-        try checkCode(c.curl_easy_getinfo(easy_handle, c.CURLINFO_RESPONSE_CODE, &status_code));
+        try checkCode(c.curl_easy_getinfo(easy_handle, c.CURLINFO_RESPONSE_CODE, &status_code), &diagnostics);
         std.debug.print("Response Code: {any}\n", .{status_code});
 
         // Get the private data (buffer) associated with this handle
         var private_data: ?*anyopaque = null;
-        try checkCode(c.curl_easy_getinfo(easy_handle, c.CURLINFO_PRIVATE, &private_data));
+        try checkCode(c.curl_easy_getinfo(easy_handle, c.CURLINFO_PRIVATE, &private_data), &diagnostics);
         const writer: *Writer = @ptrCast(@alignCast(private_data.?));
 
         std.debug.print("Response body: {s}\n", .{writer.buffered()});

examples/post.zig

@@ -8,7 +8,7 @@ pub fn main() !void {
 
     const ca_bundle = try curl.allocCABundle(allocator);
     defer ca_bundle.deinit();
-    const easy = try curl.Easy.init(.{
+    var easy = try curl.Easy.init(.{
         .ca_bundle = ca_bundle,
     });
     defer easy.deinit();

examples/upload.zig

@@ -13,7 +13,7 @@ pub fn main() !void {
 
     const ca_bundle = try curl.allocCABundle(allocator);
     defer ca_bundle.deinit();
-    const easy = try curl.Easy.init(.{
+    var easy = try curl.Easy.init(.{
         .ca_bundle = ca_bundle,
     });
     defer easy.deinit();
@@ -37,10 +37,10 @@ pub fn main() !void {
     easy.reset();
 
     // Upload with multipart/form-data
-    try multipartUpload(allocator, easy);
+    try multipartUpload(allocator, &easy);
 }
 
-fn multipartUpload(allocator: Allocator, easy: curl.Easy) !void {
+fn multipartUpload(allocator: Allocator, easy: *curl.Easy) !void {
     std.debug.print("Multipart upload demo\n", .{});
     try easy.setUrl(URL);
     var multi_part = try easy.createMultiPart();