NAME
Net::Async::OpenExchRates - interact with OpenExchangeRates API
via IO::Async
SYNOPSIS
use Future::AsyncAwait;
use IO::Async::Loop;
use Net::Async::OpenExchRates;
my $loop = IO::Async::Loop->new();
my $exch = Net::Async::OpenExchRates->new(
app_id => 'APP_ID',
);
$loop->add( $exch );
my $latest = await $exch->latest();
DESCRIPTION
This module is a simple IO::Async::Notifier wrapper class with a
Net::Async::HTTP object constructed using Object::Pad. Made to
communicate with OpenExchangeRates API providing all its available
endpoints as methods to be called by a program.
Acting as an active Asynchronous API package for Open Exchange Rates
following its API docs
along with providing extra
functionalities like pre-validation, local caching and respecting API
update frequency depending on your APP_ID subscription plan.
For examples and more ways to use this package, please check Examples
directory in package distribution page
CONSTRUCTOR
new
$exch = Net::Async::OpenExchRates->new( %args );
Returns a new Net::Async::OpenExchRates instance, which is a
IO::Async::Notifier too, where one argument is required with others
being optional, detailed as so:
app_id => STRING (REQUIRED)
The only required argument to be passed. Can be obtained from
OpenExchangeRates Account page
.
base_uri => STRING
default: 'https://openexchangerates.org'
The URL to be used as the base to form API request URI.
use_cache => BOOL
default: 1
Toggle to enable/disable the use of Cache::LRU to have the response
locally available for repeated requests only if the API responded
with 304 HTTP code for a previously cached request. As
OpenExchangeRates API offers Cache Control
utilizing ETag
identifiers. Having this enabled is effective for saving on network
bandwidth and faster responses, but not much on API usage quota as it
will still be counted as a resource request.
cache_size => INT
default: 1024
The size limit for the Cache::LRU object. The maximum number of
previous requests responses to be kept in memory.
respect_api_frequency => BOOL
default: 1
As every OpenExchangeRates API subscription plan
comes with its own number of
permitted requests per month and resources update frequency. This
option is made purely to allow your program to query repeated
requests without overwhelming API. If the request is already cached
meaning we already have its response from a previous request
invocation, it will check on the current resources update_frequency
from usage.json API call, if the Last-Modified timestamp HTTP header
that is attached with our existing response compared to current time
is less than update_frequency then most probably even if we call the
API it will return 304 HTTP, hence in this case respect the API and
instead of requesting it to confirm, return the response we already
have without requesting again.
Suitable for repeated requests, and using a restricted subscription
plan.
enable_pre_validation => BOOL
default: 1
Mainly requested currencies, date/time values along with other
limitations for some endpoints. These options are here to toggle
whether to validate those parameters before requesting them or not.
local_conversion => BOOL
default: 1
Given that convert API endpoint is only available for Unlimited
subscription plan, this option is to allow your program to perform
conversion function locally, without applying any formatting to
calculated amount. Not that if you want to use the API instead for
"convert" method you need to pass this as 0
keep_http_response => BOOL
default: 1
Used to allow your program to access the complete HTTP::Response from
the last API request made through "last_http_response". If turned of
by passing 0 last_http_response will stay empty.
METHODS
All available methods are async/await following Future::AsyncAwait and
Future
do_request
await $exch->do_request($page, %args);
The generic method to perform HTTP request for any OpenExchangeRates
API endpoint. It has the gist of the logic, from trying to check Cache
if the request has been made before to actually triggering the request
and parse its response. Takes to main arguments:
$page
as in the endpoint name that needs to be requested.
%args
A hash containing the named parameters to be passed as query
parameters to the API call URI.
use only when you want parse the complete request yourself, you should
be able to get all whats needed from API using other methods.
latest
await $exch->latest();
await $exch->latest('USD', 'CAD', ['JPY']);
To request latest.json enpoint
from API. It
accepts a list, ARRAYref or a mixture of both for currencies as an
argument where:
$base currency
as the first param where its default: 'USD'
@symbols
the rest of the list as symbols to be filtered.
Note that show_alternative is always passed as true to the API.
historical
await $exch->historical($date, $base, @symbols);
await $exch->historical('2024-04-04', 'CAD');
To request historical/*.json endpoint
from
API. Used to retrieve old rates, takes multiple parameters:
$date
required parameter; scalar string following a date format YYYY-MM-DD
$base
base currency to be used with the request, default: 'USD'.
@symbols
the rest of parameters will be taken the list of symbols to be
filtered out. Can be passed as a flat list, an ARRAYref or mix of
both.
note that show alternative is always on.
currencies
await $exch->currencies();
# to list inactive currencies
await $exch->currencies(0, 1);
To request currencies.json endpoint
from
API. it mainly returns list of offered currencies by OpenExchangeRates
API. takes two optional parameters:
$show_alternative
passed as 0 or 1, donating to include alternative currencies or not.
$show_inactive
passed as 0 or 1, donating to list inactive currencies or not.
time_series
await $exch->time_series($start, $end, $base, @symbols);
await $exch->time_series('2024-04-02', '2024-04-04');
To request time-series.json endpoint
from
API. Essentially its multiple historical requests just handled by
OpenExchangeRates API itself. Takes a couple of parameters:
$start
Required start date of the period needed. Following YYYY-MM-DD
format.
$end
Required end date of the period needed. Following YYYY-MM-DD format.
$base
Base currency for the prices requested. default: 'USD'
@symbols
Symbols to be filtered out, can be passed as a flat list list or an
ARRAYref
convert
await $exch->convert($value, $from, $to, $reverse_convert);
await $exch->convert(22, 'USD', 'CAD');
await $exch->convert(22, 'JPY', 'USD', 1);
To request convert endpoint
from API. This
endpoint is only available in Unlimited subscription plan, however you
can enable "local_conversion" which will allow you to perform
conversion operation locally, applying a simple math equation with no
formatting to returned value so make sure to apply your own decimal
point limit to returned value. Accepts these parameters:
$value
The amount you'd like to be converted. keep in mind that
OpenExchangeRates API only accepts INT values. However enabling
"local_conversion" will accept none integer values too and be able to
convert it.
$from
The currency of the $value passed above, passed as three characters.
$to
The currency to be converted to.
$reverse_convert
This is used when "local_conversion" is enabled, in order to overcome
another restriction on API. Which is to get the prices of base
currencies other than USD. Set it to 1 when you want to make it to
use $to for base to convert, and let it be as default: 0 to use $from
currency as the base to convert.
In order for "local_conversion" to work properly with Free subscription
plans, one of the currencies has to be USD where you'd set
"$reverse_convert" to 1 when you are converting $to USD rather than
$from.
ohlc
await $exch->ohlc($date, $time, $period, $base, @symbols);
await $exch->ohlc('2024-04-04', '02:00', '2m');
To request ohlc.json endpoint
from API.
Retrieving OHLC data requires some parameters to be present which are:
$date
Date for selection timeframe needed, follows YYYY-MM-DD format.
$time
Time for selection timeframe needed, follows hh:mm or h:m. All
timings would be based on UTC, as thats what API supports.
$period
Period of OHLC needed, like: '1m', '12h, '1d', and so on.
$base
Optional base currency, default: 'USD'
@symbols
Optional list of symbols to filter result based on.
usage
await $exch->usage();
To request usage.json endpoint
from API.
returning both subscription plan details and app_id API usage so far,
along with current app status.
app_plan
await $exch->app_plan();
await $exch->app_plan($key);
Retrieves only the subscription plan details from "usage" call, with
the possibility of passing:
$key
to get a specific key value from subscription plan details.
app_usage
await $exch->app_usage();
await $exch->app_usage($key);
Retrieves only the application current API usage section from "usage"
method.
$key
A specific key to get value for from API usage.
app_features
await $exch->app_features();
await $exch->app_features($key);
Retrieves the features that are currently enabled for current app_id,
accepts:
$key
as a specific feature, in order to know whether its enabled or not by
API
app_status
await $exch->app_status();
Gets the current app_id status on the API, originally in "usage" call.
plan_update_frequency
await $open_exch_api->plan_update_frequency();
used in order to specifically retrieve the subscription plan
update_frequency in seconds. Which is the rate that data are refreshed
on current active plan.
FIELD ACCESSORS
No real difference between the other typical methods except that they
are not async/await. Also for most of them they will only be populated
after the first request.
last_http_response
$exch->last_http_response();
Used to access the complete HTTP::Response for the last request that
has been made.
app_id
$exch->app_id();
The current APP_ID that is registered with this instance.
api_query_params
$exch->api_query_params();
Referenece of the list of parameters accepted by API.
app_plan_keys
$exch->app_plan_keys();
To get list of subscription plan response hash keys from "usage" call.
app_usage_keys
$exch->app_usage_keys();
To get list of current API usage response hash keys from "usage" call.
app_features_keys
$exch->app_features_keys();
To get list of available API features.