A base URL must be an absolute http(s) URL. The default transport already gates
the scheme per hop, but the engine is exported as a library and may be handed a
custom transport that does no such check, so the configured base URL is checked
up front too (a file:/ftp: base URL fails fast). A user name or password in it
is rejected as well (the API needs none; the reason never repeats them). The reasons
match the CLI's --base-url parser, which calls this rule.
A base URL must be an absolute http(s) URL. The default transport already gates the scheme per hop, but the engine is exported as a library and may be handed a custom transport that does no such check, so the configured base URL is checked up front too (a
file:/ftp:base URL fails fast). A user name or password in it is rejected as well (the API needs none; the reason never repeats them). The reasons match the CLI's--base-urlparser, which calls this rule.