tesla v1.2.0 Tesla View Source
A HTTP toolkit for building API clients using middlewares
Building API client
use Tesla
macro will generate basic http functions (e.g. get, post) inside your module.
It supports following options:
:only
- builder will generate only functions included in list given in this option:except
- builder won’t generate functions included in list given in this option:docs
- when set to false builder will won’t add documentation to generated functions
Example
defmodule ExampleApi do
use Tesla, only: [:get], docs: false
plug Tesla.Middleware.BaseUrl, "http://api.example.com"
plug Tesla.Middleware.JSON
def fetch_data do
get("/data")
end
end
In example above ExampleApi.fetch_data/0
is equivalent of ExampleApi.get("/data")
Direct usage
It is also possible to do request directly with Tesla
module.
Tesla.get("https://example.com")
Common pitfalls
Direct usage won’t include any middlewares.
In following example:
defmodule ExampleApi do
use Tesla, only: [:get], docs: false
plug Tesla.Middleware.BaseUrl, "http://api.example.com"
plug Tesla.Middleware.JSON
def fetch_data do
Tesla.get("/data")
end
end
call to ExampleApi.fetch_data/0
will fail, because request will be missing base url.
Default adapter
By default Tesla
is using Tesla.Adapter.Httpc
, because :httpc
is included in Erlang/OTP and
doen not require installation of any additional dependency. It can be changed globally with config
config :tesla, :adapter, Tesla.Adapter.Hackney
or by Tesla.Builder.adapter/2
macro for given API client module
defmodule ExampleApi do
use Tesla
adapter Tesla.Adapter.Hackney
...
end
Link to this section Summary
Functions
Dynamically build client from list of middlewares and/or adapter
Perform a DELETE request
Perform a DELETE request
Perform a GET request
Perform a GET request
Returns value of header specified by key
from :headers
field in Tesla.Env
Perform a HEAD request
Perform a HEAD request
Perform a OPTIONS request
Perform a OPTIONS request
Perform a PATCH request
Perform a PATCH request
Perform a POST request
Perform a POST request
Perform a PUT request
Perform a PUT request
Adds given key/value pair to :opts
field in Tesla.Env
Perform request and raise in case of error
Perform a request
Perform a TRACE request
Perform a TRACE request
Link to this section Types
option() :: {:method, Tesla.Env.method()} | {:url, Tesla.Env.url()} | {:query, Tesla.Env.query()} | {:headers, Tesla.Env.headers()} | {:body, Tesla.Env.body()} | {:opts, Tesla.Env.opts()}
Link to this section Functions
client([Tesla.Client.middleware()], Tesla.Client.adapter()) :: Tesla.Client.t()
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)
delete!(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.t() | no_return()
Perform a DELETE request.
See request!/1
or request!/2
for options definition.
delete!("/users")
delete!("/users", query: [scope: "admin"])
delete!(client, "/users")
delete!(client, "/users", query: [scope: "admin"])
delete(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.result()
Perform a DELETE request.
See request/1
or request/2
for options definition.
delete("/users")
delete("/users", query: [scope: "admin"])
delete(client, "/users")
delete(client, "/users", query: [scope: "admin"])
delete_header(Tesla.Env.t(), binary()) :: Tesla.Env.t()
get!(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.t() | no_return()
Perform a GET request.
See request!/1
or request!/2
for options definition.
get!("/users")
get!("/users", query: [scope: "admin"])
get!(client, "/users")
get!(client, "/users", query: [scope: "admin"])
get(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.result()
Perform a GET request.
See request/1
or request/2
for options definition.
get("/users")
get("/users", query: [scope: "admin"])
get(client, "/users")
get(client, "/users", query: [scope: "admin"])
get_header(Tesla.Env.t(), binary()) :: binary() | nil
Returns value of header specified by key
from :headers
field in Tesla.Env
Examples
# non existing header
iex> env = %Tesla.Env{headers: [{"server", "Cowboy"}]}
iex> Tesla.get_header(env, "some-key")
nil
# existing header
iex> env = %Tesla.Env{headers: [{"server", "Cowboy"}]}
iex> Tesla.get_header(env, "server")
"Cowboy"
# first of multiple headers with the same name
iex> env = %Tesla.Env{headers: [{"cookie", "chocolate"}, {"cookie", "biscuits"}]}
iex> Tesla.get_header(env, "cookie")
"chocolate"
get_headers(Tesla.Env.t(), binary()) :: [binary()]
head!(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.t() | no_return()
Perform a HEAD request.
See request!/1
or request!/2
for options definition.
head!("/users")
head!("/users", query: [scope: "admin"])
head!(client, "/users")
head!(client, "/users", query: [scope: "admin"])
head(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.result()
Perform a HEAD request.
See request/1
or request/2
for options definition.
head("/users")
head("/users", query: [scope: "admin"])
head(client, "/users")
head(client, "/users", query: [scope: "admin"])
options!(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.t() | no_return()
Perform a OPTIONS request.
See request!/1
or request!/2
for options definition.
options!("/users")
options!("/users", query: [scope: "admin"])
options!(client, "/users")
options!(client, "/users", query: [scope: "admin"])
options(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.result()
Perform a OPTIONS request.
See request/1
or request/2
for options definition.
options("/users")
options("/users", query: [scope: "admin"])
options(client, "/users")
options(client, "/users", query: [scope: "admin"])
patch!(Tesla.Env.client(), Tesla.Env.url(), Tesla.Env.body(), [option()]) :: Tesla.Env.t() | no_return()
Perform a PATCH request.
See request!/1
or request!/2
for options definition.
patch!("/users", %{name: "Jon"})
patch!("/users", %{name: "Jon"}, query: [scope: "admin"])
patch!(client, "/users", %{name: "Jon"})
patch!(client, "/users", %{name: "Jon"}, query: [scope: "admin"])
patch(Tesla.Env.client(), Tesla.Env.url(), Tesla.Env.body(), [option()]) :: Tesla.Env.result()
Perform a PATCH request.
See request/1
or request/2
for options definition.
patch("/users", %{name: "Jon"})
patch("/users", %{name: "Jon"}, query: [scope: "admin"])
patch(client, "/users", %{name: "Jon"})
patch(client, "/users", %{name: "Jon"}, query: [scope: "admin"])
post!(Tesla.Env.client(), Tesla.Env.url(), Tesla.Env.body(), [option()]) :: Tesla.Env.t() | no_return()
Perform a POST request.
See request!/1
or request!/2
for options definition.
post!("/users", %{name: "Jon"})
post!("/users", %{name: "Jon"}, query: [scope: "admin"])
post!(client, "/users", %{name: "Jon"})
post!(client, "/users", %{name: "Jon"}, query: [scope: "admin"])
post(Tesla.Env.client(), Tesla.Env.url(), Tesla.Env.body(), [option()]) :: Tesla.Env.result()
Perform a POST request.
See request/1
or request/2
for options definition.
post("/users", %{name: "Jon"})
post("/users", %{name: "Jon"}, query: [scope: "admin"])
post(client, "/users", %{name: "Jon"})
post(client, "/users", %{name: "Jon"}, query: [scope: "admin"])
put!(Tesla.Env.client(), Tesla.Env.url(), Tesla.Env.body(), [option()]) :: Tesla.Env.t() | no_return()
Perform a PUT request.
See request!/1
or request!/2
for options definition.
put!("/users", %{name: "Jon"})
put!("/users", %{name: "Jon"}, query: [scope: "admin"])
put!(client, "/users", %{name: "Jon"})
put!(client, "/users", %{name: "Jon"}, query: [scope: "admin"])
put(Tesla.Env.client(), Tesla.Env.url(), Tesla.Env.body(), [option()]) :: Tesla.Env.result()
Perform a PUT request.
See request/1
or request/2
for options definition.
put("/users", %{name: "Jon"})
put("/users", %{name: "Jon"}, query: [scope: "admin"])
put(client, "/users", %{name: "Jon"})
put(client, "/users", %{name: "Jon"}, query: [scope: "admin"])
put_body(Tesla.Env.t(), Tesla.Env.body()) :: Tesla.Env.t()
put_header(Tesla.Env.t(), binary(), binary()) :: Tesla.Env.t()
put_headers(Tesla.Env.t(), [{binary(), binary()}]) :: Tesla.Env.t()
put_opt(Tesla.Env.t(), atom(), any()) :: Tesla.Env.t()
Adds given key/value pair to :opts
field in Tesla.Env
Useful when there’s need to store additional middleware data in Tesla.Env
Example
iex> %Tesla.Env{opts: []} |> Tesla.put_opt(:option, "value")
%Tesla.Env{opts: [option: "value"]}
request!(Tesla.Env.client(), [option()]) :: Tesla.Env.t() | no_return()
Perform request and raise in case of error.
This is similar to request/2
behaviour from Tesla 0.x
See request/2
for list of available options.
request(Tesla.Env.client(), [option()]) :: Tesla.Env.result()
Perform a request
Options:
:method
- the request method, one of [:head, :get, :delete, :trace, :options, :post, :put, :patch]:url
- either full url e.g. “http://example.com/some/path” or just “/some/path” if usingTesla.Middleware.BaseUrl
:query
- a keyword list of query params, e.g.[page: 1, per_page: 100]
:headers
- a keyworld list of headers, e.g.[{"content-type", "text/plain"}]
:body
- depends on used middleware:- by default it can be a binary
- if using e.g. JSON encoding middleware it can be a nested map
- if adapter supports it it can be a Stream with any of the above
:opts
- custom, per-request middleware or adapter options
Examples:
ExampleApi.request(method: :get, url: "/users/path")
You can also use shortcut methods like:
ExampleApi.get("/users/1")
or
ExampleApi.post(client, "/users", %{name: "Jon"})
trace!(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.t() | no_return()
Perform a TRACE request.
See request!/1
or request!/2
for options definition.
trace!("/users")
trace!("/users", query: [scope: "admin"])
trace!(client, "/users")
trace!(client, "/users", query: [scope: "admin"])
trace(Tesla.Env.client(), Tesla.Env.url(), [option()]) :: Tesla.Env.result()
Perform a TRACE request.
See request/1
or request/2
for options definition.
trace("/users")
trace("/users", query: [scope: "admin"])
trace(client, "/users")
trace(client, "/users", query: [scope: "admin"])