我看到通过apex_web_service.make_rest_request发送文件的两种方法。在我的示例中，我使用了从表SAMPLE_TABLE列BLOB_TABLE中检索的图像文件blob。

选项1：

直接从查询中将文件blob类型缓存到blob对象中，并通过p_body_blob参数发送

DECLARE 
    obj_sample SAMPLE_TABLE%ROWTYPE;     
    file_blob blob;
    l_response clob;
BEGIN 
    -- query
    select * INTO obj_sample 
    from SAMPLE_TABLE where ID = 123;

    -- file as blob
    file_blob := obj_sample.BLOB_LOGO; 

    l_response   := apex_web_service.make_rest_request(
        p_url           => 'url/to/api/',
        p_http_method   => 'POST',
        p_body_blob     => file_blob,
        p_proxy_override => 'url/to/proxy'
    );
    dbms_output.put_line(l_response);
END;

选项二：

首先将文件blob数据类型转换为base64 clob对象，并通过p_body参数将其作为json body（clob）发送

DECLARE 
    obj_sample SAMPLE_TABLE%ROWTYPE; 
    json_sample clob; 
    file_clob clob;
    l_response clob;
BEGIN 
    -- query
    select * INTO obj_sample 
    from SAMPLE_TABLE where ID = 123;

    -- file as clob
    file_clob := apex_web_service.blob2clobbase64(obj_sample.BLOB_LOGO); 
    json_sample := json_object(
        'SAMPLE_LOGO' value img_clob
    );

    apex_web_service.g_request_headers(1).name := 'Content-Type';
    apex_web_service.g_request_headers(1).value := 'application/json';
    l_response   := apex_web_service.make_rest_request(
        p_url           => 'url/to/api/',
        p_http_method   => 'POST',
        p_body          => json_sample,
        p_proxy_override => 'url/to/proxy'
    );
    dbms_output.put_line(l_response);
END;

docs