Bitcoin price widget.

Async receiving bitcoin price.
Simple text widget. Provides a price in any currency by code:
(https://en.wikipedia.org/wiki/ISO_4217)

contrib/README.md

@@ -60,6 +60,18 @@ Supported platforms: Linux (required tools: `sysfs`)
 
 **vicious.contrib.batproc**
 
+**vicious.contrib.btc**
+
+Provides current Bitcoin price in any currency by code (
+https://en.wikipedia.org/wiki/ISO_4217).
+Supported platforms: Linux, FreeBSD (required tools: `curl`)
+
+- Arguments:
+  * takes currency code, i.e. `"usd"`, `"rub"` and other. `"usd"` by
+    default
+- Returns
+  * a table with string keys: {price}
+
 **vicious.contrib.countfiles**
 
 **vicious.widgets.cmus**

contrib/btc_all.lua

@@ -0,0 +1,57 @@
+---------------------------------------------------
+-- Licensed under the GNU General Public License v2
+--  * (c) 2017, 0x5b <dragen15051@gmail.com>
+---------------------------------------------------
+
+-- {{{ Grab environment
+local setmetatable = setmetatable
+local pcall = pcall
+local helpers = require("vicious.helpers")
+local spawn = require("awful.spawn")
+local json = require("json")
+local string = {
+    sub = string.sub,
+    upper = string.upper,
+}
+-- }}}
+
+
+-- Btc: provides current bitcoin price
+-- vicious.widgets.btc
+local btc_linux = {}
+
+
+-- {{ Bitcoin widget type
+function btc_linux.async(format, warg, callback)
+    -- Default values
+    if not warg then warg = "usd" end
+
+    local btc = { ["{price}"] = "N/A" }
+    local currency_code = string.upper(warg)
+    local url = "https://api.coindesk.com/v1/bpi/currentprice/" .. currency_code .. ".json"
+    local cmd = "curl "..helpers.shellquote(url)
+
+    -- {{ Checking response
+    local function parse(response)
+        -- If 'response' is not json, 'json.decode' will return Error
+        local status, data = pcall(function() return json.decode(response) end)
+        if not status or not data then
+            return btc
+        end
+
+        btc["{price}"] = string.sub(data["bpi"][currency_code]["rate"], 0, -3)
+        return btc
+    end
+    -- }}
+
+    spawn.easy_async(cmd, function(stdout) callback(parse(stdout)) end)
+end
+-- }}}
+
+-- {{ Bitcoin widget type
+local function worker(format, warg)
+    btc_linux.async(format, warg, function(data) return data end)
+end
+-- }}}
+
+return setmetatable(btc_linux, { __call = function(_, ...) return worker(...) end })

contrib/btc_linux.lua

@@ -0,0 +1,57 @@
+---------------------------------------------------
+-- Licensed under the GNU General Public License v2
+--  * (c) 2017, 0x5b <dragen15051@gmail.com>
+---------------------------------------------------
+
+-- {{{ Grab environment
+local setmetatable = setmetatable
+local pcall = pcall
+local helpers = require("vicious.helpers")
+local spawn = require("awful.spawn")
+local json = require("json")
+local string = {
+    sub = string.sub,
+    upper = string.upper,
+}
+-- }}}
+
+
+-- Btc: provides current bitcoin price
+-- vicious.widgets.btc
+local btc_linux = {}
+
+
+-- {{ Bitcoin widget type
+function btc_linux.async(format, warg, callback)
+    -- Default values
+    if not warg then warg = "usd" end
+
+    local btc = { ["{price}"] = "N/A" }
+    local currency_code = string.upper(warg)
+    local url = "https://api.coindesk.com/v1/bpi/currentprice/" .. currency_code .. ".json"
+    local cmd = "curl "..helpers.shellquote(url)
+
+    -- {{ Checking response
+    local function parse(response)
+        -- If 'response' is not json, 'json.decode' will return Error
+        local status, data = pcall(function() return json.decode(response) end)
+        if not status or not data then
+            return btc
+        end
+
+        btc["{price}"] = string.sub(data["bpi"][currency_code]["rate"], 0, -3)
+        return btc
+    end
+    -- }}
+
+    spawn.easy_async(cmd, function(stdout) callback(parse(stdout)) end)
+end
+-- }}}
+
+-- {{ Bitcoin widget type
+local function worker(format, warg)
+    btc_linux.async(format, warg, function(data) return data end)
+end
+-- }}}
+
+return setmetatable(btc_linux, { __call = function(_, ...) return worker(...) end })