access raw query params w/o allocator, close #40

examples/http_params/http_params.zig

@@ -47,6 +47,27 @@ pub fn main() !void {
             var param_count = r.getParamCount();
             std.log.info("param_count: {}", .{param_count});
 
+            // ================================================================
+            // Access RAW params from querystring
+            // ================================================================
+
+            // let's get param "one" by name
+            std.debug.print("\n", .{});
+            if (r.getParamSlice("one")) |maybe_str| {
+                std.log.info("Param one = {s}", .{maybe_str});
+            } else {
+                std.log.info("Param one not found!", .{});
+            }
+
+            var arg_it = r.getParamSlices();
+            while (arg_it.next()) |param| {
+                std.log.info("ParamStr `{s}` is `{s}`", .{ param.name, param.value });
+            }
+
+            // ================================================================
+            // Access DECODED and typed params
+            // ================================================================
+
             // iterate over all params as strings
             var strparams = r.parametersToOwnedStrList(alloc, false) catch unreachable;
             defer strparams.deinit();
@@ -82,15 +103,10 @@ pub fn main() !void {
             }
 
             // check if we received a terminate=true parameter
-            if (r.getParamStr(alloc, "terminate", false)) |maybe_str| {
-                if (maybe_str) |*s| {
-                    defer s.deinit();
-                    if (std.mem.eql(u8, s.str, "true")) {
-                        zap.stop();
-                    }
+            if (r.getParamSlice("terminate")) |maybe_str| {
+                if (std.mem.eql(u8, maybe_str, "true")) {
+                    zap.stop();
                 }
-            } else |err| {
-                std.log.err("cannot check for terminate param: {any}\n", .{err});
             }
         }
     };

src/request.zig

@@ -737,3 +737,59 @@ pub fn getParamStr(self: *const Self, a: std.mem.Allocator, name: []const u8, al
     }
     return try util.fio2strAllocOrNot(a, value, always_alloc);
 }
+
+/// similar to getParamStr, except it will return the part of the querystring
+/// after the equals sign, non-decoded, and always as character slice.
+/// - no allocation!
+/// - does not requre parseQuery() or anything to be called in advance
+pub fn getParamSlice(self: *const Self, name: []const u8) ?[]const u8 {
+    if (self.query) |query| {
+        var amp_it = std.mem.tokenizeScalar(u8, query, '&');
+        while (amp_it.next()) |maybe_pair| {
+            if (std.mem.indexOfScalar(u8, maybe_pair, '=')) |pos_of_eq| {
+                const pname = maybe_pair[0..pos_of_eq];
+                if (std.mem.eql(u8, pname, name)) {
+                    if (maybe_pair.len > pos_of_eq) {
+                        const pval = maybe_pair[pos_of_eq + 1 ..];
+                        return pval;
+                    }
+                }
+            }
+        }
+    }
+    return null;
+}
+
+pub const ParameterSlices = struct { name: []const u8, value: []const u8 };
+
+pub const ParamSliceIterator = struct {
+    amp_it: std.mem.TokenIterator(u8, .scalar),
+
+    pub fn init(query: []const u8) @This() {
+        // const query = r.query orelse "";
+        return .{
+            .amp_it = std.mem.tokenizeScalar(u8, query, '&'),
+        };
+    }
+
+    pub fn next(self: *@This()) ?ParameterSlices {
+        while (self.amp_it.next()) |maybe_pair| {
+            if (std.mem.indexOfScalar(u8, maybe_pair, '=')) |pos_of_eq| {
+                const pname = maybe_pair[0..pos_of_eq];
+                if (maybe_pair.len > pos_of_eq) {
+                    const pval = maybe_pair[pos_of_eq + 1 ..];
+                    return .{ .name = pname, .value = pval };
+                }
+            }
+        }
+        return null;
+    }
+};
+
+/// Returns an iterator that yields all query parameters on next() in the
+/// form of a ParameterSlices struct { .name, .value }
+/// As with getParamSlice(), the value is not decoded
+pub fn getParamSlices(self: *const Self) ParamSliceIterator {
+    const query = self.query orelse "";
+    return ParamSliceIterator.init(query);
+}

src/tests/test_http_params.zig

@@ -33,6 +33,8 @@ test "http parameters" {
         var strParams: ?zap.Request.HttpParamStrKVList = null;
         var params: ?zap.Request.HttpParamKVList = null;
         var paramOneStr: ?zap.FreeOrNot = null;
+        var paramOneSlice: ?[]const u8 = null;
+        var paramSlices: zap.Request.ParamSliceIterator = undefined;
 
         pub fn on_request(r: zap.Request) void {
             ran = true;
@@ -49,6 +51,14 @@ test "http parameters" {
             if (maybe_str) |*s| {
                 paramOneStr = s.*;
             }
+
+            paramOneSlice = blk: {
+                if (r.getParamSlice("one")) |val| break :blk alloc.dupe(u8, val) catch unreachable;
+                break :blk null;
+            };
+
+            // paramSlices = zap.Request.ParamSliceIterator.init(r);
+            paramSlices = r.getParamSlices();
         }
     };
 
@@ -85,12 +95,18 @@ test "http parameters" {
             // allocator.free(p);
             p.deinit();
         }
+
+        if (Handler.paramOneSlice) |p| {
+            Handler.alloc.free(p);
+        }
     }
 
     try std.testing.expectEqual(Handler.ran, true);
     try std.testing.expectEqual(Handler.param_count, 5);
     try std.testing.expect(Handler.paramOneStr != null);
     try std.testing.expectEqualStrings(Handler.paramOneStr.?.str, "1");
+    try std.testing.expect(Handler.paramOneSlice != null);
+    try std.testing.expectEqualStrings(Handler.paramOneSlice.?, "1");
     try std.testing.expect(Handler.strParams != null);
     for (Handler.strParams.?.items, 0..) |kv, i| {
         switch (i) {
@@ -118,6 +134,34 @@ test "http parameters" {
         }
     }
 
+    var pindex: usize = 0;
+    while (Handler.paramSlices.next()) |param| {
+        switch (pindex) {
+            0 => {
+                try std.testing.expectEqualStrings(param.name, "one");
+                try std.testing.expectEqualStrings(param.value, "1");
+            },
+            1 => {
+                try std.testing.expectEqualStrings(param.name, "two");
+                try std.testing.expectEqualStrings(param.value, "2");
+            },
+            2 => {
+                try std.testing.expectEqualStrings(param.name, "string");
+                try std.testing.expectEqualStrings(param.value, "hello+world");
+            },
+            3 => {
+                try std.testing.expectEqualStrings(param.name, "float");
+                try std.testing.expectEqualStrings(param.value, "6.28");
+            },
+            4 => {
+                try std.testing.expectEqualStrings(param.name, "bool");
+                try std.testing.expectEqualStrings(param.value, "true");
+            },
+            else => return error.TooManyArgs,
+        }
+        pindex += 1;
+    }
+
     for (Handler.params.?.items, 0..) |kv, i| {
         switch (i) {
             0 => {