Tesla.client

You're seeing just the function client, go back to Tesla module for more information.
Link to this function

client(middleware, adapter \\ nil)

View Source (since 1.2.0)

Specs

Dynamically build client from list of middlewares and/or adapter.

# add dynamic middleware
client = Tesla.client([{Tesla.Middleware.Headers, [{"authorization", token}]}])
Tesla.get(client, "/path")

# configure adapter in runtime
client = Tesla.client([], Tesla.Adapter.Hackney)
client = Tesla.client([], {Tesla.Adapter.Hackney, pool: :my_pool})
Tesla.get(client, "/path")

# complete module example
defmodule MyApi do
  # note there is no need for `use Tesla`

  @middleware [
    {Tesla.Middleware.BaseUrl, "https://example.com"},
    Tesla.Middleware.JSON,
    Tesla.Middleware.Logger
  ]

  @adapter Tesla.Adapter.Hackney

  def new(opts) do
    # do any middleware manipulation you need
    middleware = [
      {Tesla.Middleware.BasicAuth, username: opts[:username], password: opts[:password]}
    ] ++ @middleware

    # allow configuring adapter in runtime
    adapter = opts[:adapter] || @adapter

    # use Tesla.client/2 to put it all together
    Tesla.client(middleware, adapter)
  end

  def get_something(client, id) do
    # pass client directly to Tesla.get/2
    Tesla.get(client, "/something/#{id}")
    # ...
  end
end

client = MyApi.new(username: "admin", password: "secret")
MyApi.get_something(client, 42)