class Oj::StringWriter - Oj

# class Oj::StringWriter

Supports building a JSON document one element at a time. Build the document by pushing values into the document. Pushing an array or an object will create that element in the JSON document and subsequent pushes will add the elements to that array or object until a pop() is called. When complete calling #to_s() will return the JSON document. Note tha calling #to_s() before construction is complete will return the document in it's current state.

### Public Class Methods

new(io, options) click to toggle source

Creates a new StringWriter. Options are supported according the the specified mode or the mode in the default options. Note that if mimic_JSON or Oj.optimize_rails has not been called then the behavior of the modes may not be the same as if they were.

In addition to the regular dump options for the various modes a :buffer_size option is available. It should be set to a positive integer. It is considered a hint of how large the initial internal buffer should be.

- io [IO] stream to write to

- options [Hash] formating options

    static VALUE
    str_writer_new(int argc, VALUE *argv, VALUE self) {
        StrWriter   sw = ALLOC(struct _StrWriter);

        oj_str_writer_init(sw, 0);
        if (1 == argc) {
            oj_parse_options(argv[0], &sw->opts);
        }
        sw->out.argc = argc - 1;
        sw->out.argv = argv + 1;
        sw->out.indent = sw->opts.indent;

        return Data_Wrap_Struct(oj_string_writer_class, 0, str_writer_free, sw);
    }

### Public Instance Methods

pop() click to toggle source

Pops up a level in the JSON document closing the array or object that is currently open.

    static VALUE
    str_writer_pop(VALUE self) {
        oj_str_writer_pop((StrWriter)DATA_PTR(self));
        return Qnil;
    }

pop_all() click to toggle source

Pops all level in the JSON document closing all the array or object that is currently open.

    static VALUE
    str_writer_pop_all(VALUE self) {
        oj_str_writer_pop_all((StrWriter)DATA_PTR(self));

        return Qnil;
    }

push_array(key=nil) click to toggle source

Pushes an array onto the JSON document. Future pushes will be to this object until a pop() is called.

- key [String] the key if adding to an object in the JSON document

    static VALUE
    str_writer_push_array(int argc, VALUE *argv, VALUE self) {
        StrWriter   sw = (StrWriter)DATA_PTR(self);

        switch (argc) {
        case 0:
            oj_str_writer_push_array(sw, 0);
            break;
        case 1:
            if (Qnil == argv[0]) {
                oj_str_writer_push_array(sw, 0);
            } else {
                rb_check_type(argv[0], T_STRING);
                oj_str_writer_push_array(sw, StringValuePtr(argv[0]));
            }
            break;
        default:
            rb_raise(rb_eArgError, "Wrong number of argument to 'push_object'.");
            break;
        }
        if (rb_block_given_p()) {
            rb_yield(Qnil);
            oj_str_writer_pop(sw);
        }
        return Qnil;
    }

push_json(value, key=nil) click to toggle source

Pushes a string onto the JSON document. The String must be a valid JSON encoded string. No additional checking is done to verify the validity of the string.

- value [Object] value to add to the JSON document

- key [String] the key if adding to an object in the JSON document

    static VALUE
    str_writer_push_json(int argc, VALUE *argv, VALUE self) {
        rb_check_type(argv[0], T_STRING);
        switch (argc) {
        case 1:
            oj_str_writer_push_json((StrWriter)DATA_PTR(self), StringValuePtr(*argv), 0);
            break;
        case 2:
            if (Qnil == argv[1]) {
                oj_str_writer_push_json((StrWriter)DATA_PTR(self), StringValuePtr(*argv), 0);
            } else {
                rb_check_type(argv[1], T_STRING);
                oj_str_writer_push_json((StrWriter)DATA_PTR(self), StringValuePtr(*argv), StringValuePtr(argv[1]));
            }
            break;
        default:
            rb_raise(rb_eArgError, "Wrong number of argument to 'push_json'.");
            break;
        }
        return Qnil;
    }

push_key(key) click to toggle source

Pushes a key onto the JSON document. The key will be used for the next push if currently in a JSON object and ignored otherwise. If a key is provided on the next push then that new key will be ignored.

- key [String] the key pending for the next push

    static VALUE
    str_writer_push_key(VALUE self, VALUE key) {
        StrWriter   sw = (StrWriter)DATA_PTR(self);

        rb_check_type(key, T_STRING);
        oj_str_writer_push_key(sw, StringValuePtr(key));

        return Qnil;
    }

push_object(key=nil) click to toggle source

Pushes an object onto the JSON document. Future pushes will be to this object until a pop() is called.

- key [String] the key if adding to an object in the JSON document

    static VALUE
    str_writer_push_object(int argc, VALUE *argv, VALUE self) {
        StrWriter   sw = (StrWriter)DATA_PTR(self);

        switch (argc) {
        case 0:
            oj_str_writer_push_object(sw, 0);
            break;
        case 1:
            if (Qnil == argv[0]) {
                oj_str_writer_push_object(sw, 0);
            } else {
                rb_check_type(argv[0], T_STRING);
                oj_str_writer_push_object(sw, StringValuePtr(argv[0]));
            }
            break;
        default:
            rb_raise(rb_eArgError, "Wrong number of argument to 'push_object'.");
            break;
        }
        if (rb_block_given_p()) {
            rb_yield(Qnil);
            oj_str_writer_pop(sw);
        }
        return Qnil;
    }

push_value(value, key=nil) click to toggle source

Pushes a value onto the JSON document.

- value [Object] value to add to the JSON document

- key [String] the key if adding to an object in the JSON document

    static VALUE
    str_writer_push_value(int argc, VALUE *argv, VALUE self) {
        switch (argc) {
        case 1:
            oj_str_writer_push_value((StrWriter)DATA_PTR(self), *argv, 0);
            break;
        case 2:
            if (Qnil == argv[1]) {
                oj_str_writer_push_value((StrWriter)DATA_PTR(self), *argv, 0);
            } else {
                rb_check_type(argv[1], T_STRING);
                oj_str_writer_push_value((StrWriter)DATA_PTR(self), *argv, StringValuePtr(argv[1]));
            }
            break;
        default:
            rb_raise(rb_eArgError, "Wrong number of argument to 'push_value'.");
            break;
        }
        return Qnil;
    }

reset() click to toggle source

Reset the writer back to the empty state.

    static VALUE
    str_writer_reset(VALUE self) {
        StrWriter   sw = (StrWriter)DATA_PTR(self);

        sw->depth = 0;
        *sw->types = '\0';
        sw->keyWritten = 0;
        sw->out.cur = sw->out.buf;
        *sw->out.cur = '\0';

        return Qnil;
    }

to_s() click to toggle source

Returns the JSON document string in what ever state the construction is at.

return [String]

    static VALUE
    str_writer_to_s(VALUE self) {
        StrWriter   sw = (StrWriter)DATA_PTR(self);
        VALUE       rstr = rb_str_new(sw->out.buf, sw->out.cur - sw->out.buf);

        return oj_encode(rstr);
    }