This topic describes how to dynamically construct fields, package existing logs as a whole, and add these logs to the new fields.

Example: The first function in the following transformation rule renames the content field in the following raw log entry to k1_content_copy, the name field to k2_name_copy, and the School field to k3_school_copy. The second function constructs a field named __extract_others__, adds the field to the transformed log entry, and drops the k1_content_copy and k3_school_copy fields.

  • Transformation rule:
    e_set("k1_content_copy", v("content"), "k2_name_copy", v("name"), "k3_school_copy", v("School"))
    e_set("__extract_others__", dct_delete(KEEP,"k1_content_copy","k3_school_copy"))
  • Raw log entry:
    School: CMU
    _tag__:__receive_time__: 1591755799
    content: test concent
    name: Twish
  • Result:
    School:  CMU
    __extract_others__:  {"__time__": "1591755799", "__topic__": "", "__source__": "", "__tag__:__client_ip__": "", "__tag__:__receive_time__": "1591755799", "content": "test content", "name": "Twish", "School": "CMU", "k2_name_copy": "Twish"}
    __tag__:__receive_time__:  1591755799
    content:  test content
    k2_name_copy:  Twish
    name:  Twish