rest json v1 basic requests (responses tbd)

This provides initial implementation with some basic calls
working. Only GET requests have been verified so far.
Http header support missing. POST/PUT might work, but
have not been tested. Currently the demo tests are
failing due to a response deserialization issue that
is still being debugged

codegen/src/main.zig

@@ -340,12 +340,32 @@ fn generateSimpleTypeFor(_: anytype, type_name: []const u8, writer: anytype, all
 
 fn generateComplexTypeFor(allocator: *std.mem.Allocator, members: []smithy.TypeMember, type_type_name: []const u8, shapes: anytype, writer: anytype, prefix: []const u8, all_required: bool, type_stack: anytype) anyerror!void {
     const Mapping = struct { snake: []const u8, json: []const u8 };
-    var mappings = try std.ArrayList(Mapping).initCapacity(allocator, members.len);
+    var json_field_name_mappings = try std.ArrayList(Mapping).initCapacity(allocator, members.len);
     defer {
-        for (mappings.items) |mapping| {
+        for (json_field_name_mappings.items) |mapping| {
             allocator.free(mapping.snake);
         }
-        mappings.deinit();
+        json_field_name_mappings.deinit();
+    }
+    // There is an httpQueryParams trait as well, but nobody is using it. API GW
+    // pretends to, but it's an empty map
+    //
+    // Same with httpPayload
+    //
+    // httpLabel is interesting - right now we just assume anything can be used - do we need to track this?
+    var http_query_mappings = try std.ArrayList(Mapping).initCapacity(allocator, members.len);
+    defer {
+        for (http_query_mappings.items) |mapping| {
+            allocator.free(mapping.snake);
+        }
+        http_query_mappings.deinit();
+    }
+    var http_header_mappings = try std.ArrayList(Mapping).initCapacity(allocator, members.len);
+    defer {
+        for (http_header_mappings.items) |mapping| {
+            allocator.free(mapping.snake);
+        }
+        http_header_mappings.deinit();
     }
     // prolog. We'll rely on caller to get the spacing correct here
     _ = try writer.write(type_type_name);
@@ -359,15 +379,20 @@ fn generateComplexTypeFor(allocator: *std.mem.Allocator, members: []smithy.TypeM
         // in API Gateway. Not sure what we're supposed to do there. Checking the go
         // sdk, they move this particular duplicate to 'http_method' - not sure yet
         // if this is a hard-coded exception`
-        var found_trait = false;
+        var found_name_trait = false;
         for (member.traits) |trait| {
-            if (trait == .json_name) {
-                found_trait = true;
-                mappings.appendAssumeCapacity(.{ .snake = try allocator.dupe(u8, snake_case_member), .json = trait.json_name });
+            switch (trait) {
+                .json_name => {
+                    found_name_trait = true;
+                    json_field_name_mappings.appendAssumeCapacity(.{ .snake = try allocator.dupe(u8, snake_case_member), .json = trait.json_name });
+                },
+                .http_query => http_query_mappings.appendAssumeCapacity(.{ .snake = try allocator.dupe(u8, snake_case_member), .json = trait.http_query }),
+                .http_header => http_header_mappings.appendAssumeCapacity(.{ .snake = try allocator.dupe(u8, snake_case_member), .json = trait.http_header }),
+                else => {},
             }
         }
-        if (!found_trait)
-            mappings.appendAssumeCapacity(.{ .snake = try allocator.dupe(u8, snake_case_member), .json = member.name });
+        if (!found_name_trait)
+            json_field_name_mappings.appendAssumeCapacity(.{ .snake = try allocator.dupe(u8, snake_case_member), .json = member.name });
         defer allocator.free(snake_case_member);
         try writer.print("{s}    {s}: ", .{ prefix, avoidReserved(snake_case_member) });
         if (!all_required) try writeOptional(member.traits, writer, null);
@@ -377,6 +402,20 @@ fn generateComplexTypeFor(allocator: *std.mem.Allocator, members: []smithy.TypeM
         _ = try writer.write(",\n");
     }
 
+    // Add in http query metadata (only relevant to REST JSON APIs - do we care?
+    // pub const http_query = .{
+    //     .master_region = "MasterRegion",
+    //     .function_version = "FunctionVersion",
+    //     .marker = "Marker",
+    //     .max_items = "MaxItems",
+    // };
+    var constprefix = try std.fmt.allocPrint(allocator, "{s}    ", .{prefix});
+    defer allocator.free(constprefix);
+    if (http_query_mappings.items.len > 0) _ = try writer.write("\n");
+    try writeMappings(constprefix, "pub ", "http_query", http_query_mappings, writer);
+    if (http_query_mappings.items.len > 0 and http_header_mappings.items.len > 0) _ = try writer.write("\n");
+    try writeMappings(constprefix, "pub ", "http_header", http_header_mappings, writer);
+
     // Add in json mappings. The function looks like this:
     //
     // pub fn jsonFieldNameFor(_: @This(), comptime field_name: []const u8) []const u8 {
@@ -387,19 +426,24 @@ fn generateComplexTypeFor(allocator: *std.mem.Allocator, members: []smithy.TypeM
     //     return @field(mappings, field_name);
     // }
     //
-    // TODO: There is a smithy trait that will specify the json name. We should be using
-    //       this instead if applicable.
+    var fieldnameprefix = try std.fmt.allocPrint(allocator, "{s}        ", .{prefix});
+    defer allocator.free(fieldnameprefix);
     try writer.print("\n{s}    pub fn jsonFieldNameFor(_: @This(), comptime field_name: []const u8) []const u8 ", .{prefix});
     _ = try writer.write("{\n");
-    try writer.print("{s}        const mappings = .", .{prefix});
+    try writeMappings(fieldnameprefix, "", "mappings", json_field_name_mappings, writer);
+    try writer.print("{s}        return @field(mappings, field_name);\n{s}", .{ prefix, prefix });
+    _ = try writer.write("    }\n");
+}
+
+fn writeMappings(prefix: []const u8, @"pub": []const u8, mapping_name: []const u8, mappings: anytype, writer: anytype) !void {
+    if (mappings.items.len == 0) return;
+    try writer.print("{s}{s}const {s} = .", .{ prefix, @"pub", mapping_name });
     _ = try writer.write("{\n");
     for (mappings.items) |mapping| {
         try writer.print("{s}    .{s} = \"{s}\",\n", .{ prefix, avoidReserved(mapping.snake), mapping.json });
     }
     _ = try writer.write(prefix);
     _ = try writer.write("};\n");
-    try writer.print("{s}        return @field(mappings, field_name);\n{s}", .{ prefix, prefix });
-    _ = try writer.write("    }\n");
 }
 
 fn writeOptional(traits: ?[]smithy.Trait, writer: anytype, value: ?[]const u8) !void {

smithy/src/smithy.zig

@@ -92,6 +92,9 @@ pub const TraitType = enum {
     aws_protocol,
     ec2_query_name,
     http,
+    http_header,
+    http_label,
+    http_query,
     json_name,
     required,
     documentation,
@@ -120,6 +123,9 @@ pub const Trait = union(TraitType) {
         uri: []const u8,
         code: i64 = 200,
     },
+    http_header: []const u8,
+    http_label: []const u8,
+    http_query: []const u8,
     required: struct {},
     documentation: []const u8,
     pattern: []const u8,
@@ -559,6 +565,10 @@ fn getTrait(trait_type: []const u8, value: std.json.Value) SmithyParseError!?Tra
     }
     if (std.mem.eql(u8, trait_type, "smithy.api#jsonName"))
         return Trait{ .json_name = value.String };
+    if (std.mem.eql(u8, trait_type, "smithy.api#httpQuery"))
+        return Trait{ .http_query = value.String };
+    if (std.mem.eql(u8, trait_type, "smithy.api#httpHeader"))
+        return Trait{ .http_header = value.String };
 
     // TODO: Maybe care about these traits?
     if (std.mem.eql(u8, trait_type, "smithy.api#title"))
@@ -583,14 +593,11 @@ fn getTrait(trait_type: []const u8, value: std.json.Value) SmithyParseError!?Tra
         \\smithy.api#eventPayload
         \\smithy.api#externalDocumentation
         \\smithy.api#hostLabel
-        \\smithy.api#http
         \\smithy.api#httpError
         \\smithy.api#httpChecksumRequired
-        \\smithy.api#httpHeader
         \\smithy.api#httpLabel
         \\smithy.api#httpPayload
         \\smithy.api#httpPrefixHeaders
-        \\smithy.api#httpQuery
         \\smithy.api#httpQueryParams
         \\smithy.api#httpResponseCode
         \\smithy.api#idempotencyToken

src/aws.zig

@@ -11,6 +11,7 @@ const log = std.log.scoped(.aws);
 pub const Options = struct {
     region: []const u8 = "aws-global",
     dualstack: bool = false,
+    success_http_code: i64 = 200,
 };
 
 /// Using this constant may blow up build times. Recommed using Services()
@@ -65,12 +66,45 @@ pub const Aws = struct {
         switch (service_meta.aws_protocol) {
             .query => return self.callQuery(request, service_meta, action, options),
             // .query, .ec2_query => return self.callQuery(request, service_meta, action, options),
-            .rest_json_1, .json_1_0, .json_1_1 => return self.callJson(request, service_meta, action, options),
+            .json_1_0, .json_1_1 => return self.callJson(request, service_meta, action, options),
+            .rest_json_1 => return self.callRestJson(request, service_meta, action, options),
             .ec2_query, .rest_xml => @compileError("XML responses may be blocked on a zig compiler bug scheduled to be fixed in 0.9.0"),
         }
     }
 
-    /// Calls using one of the json protocols (rest_json_1, json_1_0, json_1_1
+    /// Rest Json is the most complex and so we handle this seperately
+    fn callRestJson(self: Self, comptime request: anytype, comptime service_meta: anytype, action: anytype, options: Options) !FullResponse(request) {
+        const Action = @TypeOf(action);
+        var aws_request: awshttp.HttpRequest = .{
+            .method = Action.http_config.method,
+            .content_type = "application/json",
+            .path = Action.http_config.uri,
+        };
+
+        log.debug("Rest JSON v1 method: {s}", .{aws_request.method});
+        log.debug("Rest JSON v1 success code: {d}", .{Action.http_config.success_code});
+        log.debug("Rest JSON v1 raw uri: {s}", .{Action.http_config.uri});
+
+        aws_request.query = try buildQuery(self.allocator, request);
+        log.debug("Rest JSON v1 query: {s}", .{aws_request.query});
+        defer self.allocator.free(aws_request.query);
+        // We don't know if we need a body...guessing here, this should cover most
+        var buffer = std.ArrayList(u8).init(self.allocator);
+        defer buffer.deinit();
+        var nameAllocator = std.heap.ArenaAllocator.init(self.allocator);
+        defer nameAllocator.deinit();
+        if (std.mem.eql(u8, "PUT", aws_request.method) or std.mem.eql(u8, "POST", aws_request.method)) {
+            try json.stringify(request, .{ .whitespace = .{} }, buffer.writer());
+        }
+
+        return try self.callAws(request, service_meta, aws_request, .{
+            .success_http_code = Action.http_config.success_code,
+            .region = options.region,
+            .dualstack = options.dualstack,
+        });
+    }
+
+    /// Calls using one of the json protocols (json_1_0, json_1_1)
     fn callJson(self: Self, comptime request: anytype, comptime service_meta: anytype, action: anytype, options: Options) !FullResponse(request) {
         const target =
             try std.fmt.allocPrint(self.allocator, "{s}.{s}", .{
@@ -97,7 +131,6 @@ pub const Aws = struct {
 
         var content_type: []const u8 = undefined;
         switch (service_meta.aws_protocol) {
-            .rest_json_1 => content_type = "application/json",
             .json_1_0 => content_type = "application/x-amz-json-1.0",
             .json_1_1 => content_type = "application/x-amz-json-1.1",
             else => unreachable,
@@ -377,6 +410,53 @@ fn queryFieldTransformer(field_name: []const u8, encoding_options: url.EncodingO
     return try case.snakeToPascal(encoding_options.allocator.?, field_name);
 }
 
+fn buildQuery(allocator: *std.mem.Allocator, comptime request: anytype) ![]const u8 {
+    // query should look something like this:
+    // pub const http_query = .{
+    //     .master_region = "MasterRegion",
+    //     .function_version = "FunctionVersion",
+    //     .marker = "Marker",
+    // };
+    const query_arguments = @TypeOf(request).http_query;
+    var buffer = std.ArrayList(u8).init(allocator);
+    const writer = buffer.writer();
+    defer buffer.deinit();
+    var has_begun = false;
+    inline for (@typeInfo(@TypeOf(query_arguments)).Struct.fields) |arg| {
+        const val = @field(request, arg.name);
+        if (@typeInfo(@TypeOf(val)) == .Optional) {
+            if (val) |v| {
+                try addQueryArg(@field(query_arguments, arg.name), v, writer, !has_begun);
+                has_begun = true;
+            }
+        } else {
+            try addQueryArg(@field(query_arguments, arg.name), val, writer, !has_begun);
+            has_begun = true;
+        }
+    }
+    return buffer.toOwnedSlice();
+}
+
+fn addQueryArg(key: []const u8, value: anytype, writer: anytype, start: bool) !void {
+    if (start)
+        _ = try writer.write("?")
+    else
+        _ = try writer.write("&");
+    // TODO: url escaping
+    try writer.print("{s}=", .{key});
+    try json.stringify(value, .{}, writer);
+}
+
+test "REST Json v1 builds proper queries" {
+    const allocator = std.testing.allocator;
+    const svs = Services(.{.lambda}){};
+    const request = svs.lambda.list_functions.Request{
+        .max_items = 1,
+    };
+    const query = try buildQuery(allocator, request);
+    defer allocator.free(query);
+    try std.testing.expectEqualStrings("?MaxItems=1", query);
+}
 test "basic json request serialization" {
     const allocator = std.testing.allocator;
     const svs = Services(.{.dynamo_db}){};

src/main.zig

@@ -31,6 +31,8 @@ const Tests = enum {
     json_1_0_query_no_input,
     json_1_1_query_with_input,
     json_1_1_query_no_input,
+    rest_json_1_query_no_input,
+    rest_json_1_query_with_input,
 };
 
 pub fn main() anyerror!void {
@@ -69,53 +71,67 @@ pub fn main() anyerror!void {
     var client = aws.Aws.init(allocator);
     defer client.deinit();
 
-    const services = aws.Services(.{ .sts, .ec2, .dynamo_db, .ecs }){};
+    const services = aws.Services(.{ .sts, .ec2, .dynamo_db, .ecs, .lambda }){};
 
     for (tests.items) |t| {
         std.log.info("===== Start Test: {s} =====", .{@tagName(t)});
         switch (t) {
             .query_no_input => {
-                const resp = try client.call(services.sts.get_caller_identity.Request{}, options);
-                defer resp.deinit();
-                std.log.info("arn: {s}", .{resp.response.arn});
-                std.log.info("id: {s}", .{resp.response.user_id});
-                std.log.info("account: {s}", .{resp.response.account});
-                std.log.info("requestId: {s}", .{resp.response_metadata.request_id});
+                const call = try client.call(services.sts.get_caller_identity.Request{}, options);
+                defer call.deinit();
+                std.log.info("arn: {s}", .{call.response.arn});
+                std.log.info("id: {s}", .{call.response.user_id});
+                std.log.info("account: {s}", .{call.response.account});
+                std.log.info("requestId: {s}", .{call.response_metadata.request_id});
             },
             .query_with_input => {
                 // TODO: Find test without sensitive info
-                const access = try client.call(services.sts.get_session_token.Request{
+                const call = try client.call(services.sts.get_session_token.Request{
                     .duration_seconds = 900,
                 }, options);
-                defer access.deinit();
-                std.log.info("access key: {s}", .{access.response.credentials.?.access_key_id});
+                defer call.deinit();
+                std.log.info("call key: {s}", .{call.response.credentials.?.access_key_id});
             },
             .json_1_0_query_with_input => {
-                const tables = try client.call(services.dynamo_db.list_tables.Request{
+                const call = try client.call(services.dynamo_db.list_tables.Request{
                     .limit = 1,
                 }, options);
-                defer tables.deinit();
-                std.log.info("request id: {s}", .{tables.response_metadata.request_id});
-                std.log.info("account has tables: {b}", .{tables.response.table_names.?.len > 0});
+                defer call.deinit();
+                std.log.info("request id: {s}", .{call.response_metadata.request_id});
+                std.log.info("account has call: {b}", .{call.response.table_names.?.len > 0});
             },
             .json_1_0_query_no_input => {
-                const limits = try client.call(services.dynamo_db.describe_limits.Request{}, options);
-                defer limits.deinit();
-                std.log.info("account read capacity limit: {d}", .{limits.response.account_max_read_capacity_units});
+                const call = try client.call(services.dynamo_db.describe_limits.Request{}, options);
+                defer call.deinit();
+                std.log.info("account read capacity limit: {d}", .{call.response.account_max_read_capacity_units});
             },
             .json_1_1_query_with_input => {
-                const clusters = try client.call(services.ecs.list_clusters.Request{
+                const call = try client.call(services.ecs.list_clusters.Request{
                     .max_results = 1,
                 }, options);
-                defer clusters.deinit();
-                std.log.info("request id: {s}", .{clusters.response_metadata.request_id});
-                std.log.info("account has clusters: {b}", .{clusters.response.cluster_arns.?.len > 0});
+                defer call.deinit();
+                std.log.info("request id: {s}", .{call.response_metadata.request_id});
+                std.log.info("account has call: {b}", .{call.response.cluster_arns.?.len > 0});
             },
             .json_1_1_query_no_input => {
-                const clusters = try client.call(services.ecs.list_clusters.Request{}, options);
-                defer clusters.deinit();
-                std.log.info("request id: {s}", .{clusters.response_metadata.request_id});
-                std.log.info("account has clusters: {b}", .{clusters.response.cluster_arns.?.len > 0});
+                const call = try client.call(services.ecs.list_clusters.Request{}, options);
+                defer call.deinit();
+                std.log.info("request id: {s}", .{call.response_metadata.request_id});
+                std.log.info("account has call: {b}", .{call.response.cluster_arns.?.len > 0});
+            },
+            .rest_json_1_query_with_input => {
+                const call = try client.call(services.lambda.list_functions.Request{
+                    .max_items = 1,
+                }, options);
+                defer call.deinit();
+                std.log.info("request id: {s}", .{call.response_metadata.request_id});
+                std.log.info("account has call: {b}", .{call.response.functions.?.len > 0});
+            },
+            .rest_json_1_query_no_input => {
+                const call = try client.call(services.lambda.list_functions.Request{}, options);
+                defer call.deinit();
+                std.log.info("request id: {s}", .{call.response_metadata.request_id});
+                std.log.info("account has call: {b}", .{call.response.functions.?.len > 0});
             },
             .ec2_query_no_input => {
                 std.log.err("EC2 Test disabled due to compiler bug", .{});