This illustration describes execution flow in UTL_HTTP that has two phases: (1) beginning with "begin_request" and ending with "end_request", (2) beginning with "get_response" and ending with "end_response".
The key to the symbols used is:
... -> (an arrow) denotes "continue to next step", for example, "begin_request" -> "get_response"
... material enclosed in double quotation marks denotes an action, for example "PARSE"
... material enclosed in single qutotation marks denotes a choice point, for example, 'perform pre-response set operations': Yes/No
... material unenclosed denotes a choice of direction, for example, Yes
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PHASE #1.
"begin_request" -> 'perform pre-response set operations': Yes/No
'perform set operations': Yes -> "set_cookie_support" (optional with option to repeat multiple times) -> "set_persistent_conn_support" (optional with option to repeat multiple times)-> "set_body_charset" (optional with option to repeat multiple times) -> "set_follow_redirect" (optional with option to repeat multiple times) ->"set_authentication" (optional with option to repeat multiple times) -> "set_header" (optional with option to repeat multiple times) -> 'perform pre-response write operations':Yes/No
'perform set operations': No -> 'perform write operations':Yes/No
'perform pre-response write operations':Yes -> "write_raw" (optional with option to repeat multiple times) -> "write_line" (optional with option to repeat multiple times) -> "write_text" (optional with option to repeat multiple times) -> "end_request"
'perform pre-response write operations': No -> "end_request"
PHASE #2.
"get_response" -> 'perform get operations': Yes/No
'perform get operations': Yes -> "set_body_charset" (optional with option to repeat multiple times) -> "get_authentication" (optional with option to repeat multiple times) -> "get_header_count" (optional with option to repeat multiple times) ->"get_header_by_name" (optional with option to repeat multiple times) -> 'peform read operations':Yes/No
'perform get operations': No -> 'peform read operations':Yes/No
'peform read operations':Yes -> "read_raw" (optional with option to repeat multiple times) ->"read_line" (optional with option to repeat multiple times) -> "read_text" (optional with option to repeat multiple times) -> end_response
'peform read operations':No -> end_response