TT#131255 NGCPPush class

* simple POST via request function
* interface to store/retrieve/delete values from a list
  at central redis

Change-Id: Ibae0f9b5c04dec3004b6d33e271866c722da3182

ngcp/push.lua

@@ -0,0 +1,238 @@
+--
+-- Copyright 2021 SipWise Team <development@sipwise.com>
+--
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation, either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This package is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program. If not, see <http://www.gnu.org/licenses/>.
+-- .
+-- On Debian systems, the complete text of the GNU General
+-- Public License version 3 can be found in "/usr/share/common-licenses/GPL-3".
+--
+
+local NGCPPush = {
+     __class__ = 'NGCPPush'
+}
+local redis = require 'redis';
+local curl = require 'curl'
+local utils = require 'ngcp.utils'
+local utable = utils.table
+local separator = "#"
+
+-- class NGCPPush
+local NGCPPush_MT = { __index = NGCPPush }
+
+NGCPPush_MT.__tostring = function (t)
+    return string.format("config:%s", utable.tostring(t.config))
+end
+
+function NGCPPush.new()
+    local t = NGCPPush.init();
+    setmetatable( t, NGCPPush_MT )
+    return t;
+end
+
+function NGCPPush.init()
+    local t = {
+        config = {
+            url   = 'http://127.0.0.1:45059/push',
+            central = {
+                host = '127.0.0.1',
+                port = 6379,
+                db = "3"
+            },
+        },
+        c = curl.easy_init(),
+        client = {},
+    };
+    return t;
+end
+
+function NGCPPush:_test_connection()
+    if not self.client then return nil end
+    local ok, _ = pcall(self.client.ping, self.client);
+    return ok
+end
+
+function NGCPPush:_connect()
+    local config = self.config.central
+    self.client = redis.connect(config.host, config.port);
+    self.client:select(config.db);
+    KSR.dbg(string.format("connected to redis server %s:%d at %s\n",
+        config.host, config.port, config.db));
+end
+
+function NGCPPush:len(key, node)
+    local values = self:get(key)
+    local res = 0
+
+    if values then
+        for _,v in pairs(values) do
+            if v.node == node then
+                res = res + 1
+            end
+        end
+    end
+    return res
+end
+
+local function value_base(v)
+    return v.idx .. separator .. v.label .. separator .. v.node .. separator .. v.node_uri
+end
+
+function NGCPPush:add(v)
+    if not self:_test_connection() then
+        self:_connect();
+    end
+    local val_base = value_base(v)
+    local val = v.callid.. separator ..val_base
+    local pos = self.client:lpush(v.key, val)
+    KSR.dbg(string.format("lpush[%s]=>[%s] %s\n",
+        v.key, val, tostring(pos)));
+
+    val = v.key .. separator .. val_base
+    pos = self.client:lpush(v.callid, val)
+    KSR.dbg(string.format("lpush[%s]=>[%s] %s\n",
+        v.callid, val, tostring(pos)));
+    if v.expire then
+        self.client.expire(v.key, v.expire)
+        self.client.expire(v.callid, v.expire)
+        KSR.dbg(string.format(
+            "set expire %d for keys:[%s, %s]", v.expire, v.key, v.callid));
+    end
+end
+
+local function split_val(value)
+    local t = utils.explode(separator, value);
+    return t[1], t[2], t[3], t[4], t[5];
+end
+
+local function insert_val(res, v, key_name)
+    local key, idx, label, node, node_uri = split_val(v)
+    local val = {idx=idx, label=label, node=node, node_uri=node_uri}
+    val[key_name] = key
+    table.insert(res, val)
+end
+
+function NGCPPush:get(key)
+    if not self:_test_connection() then
+        self:_connect();
+    end
+    local res = {}
+    for _,v in pairs(self.client:lrange(key, 0, -1)) do
+        insert_val(res, v, "callid")
+    end
+    return res
+end
+
+function NGCPPush:callid_get(callid)
+    if not self:_test_connection() then
+        self:_connect();
+    end
+    local res = {}
+    for _,v in pairs(self.client:lrange(callid, 0, -1)) do
+        insert_val(res, v, "key")
+    end
+    return res
+end
+
+function NGCPPush:del(v)
+    if not self:_test_connection() then
+        self:_connect();
+    end
+    local val_base = value_base(v)
+    local val = v.callid.. separator ..val_base
+    local res = self.client:lrem(v.key, 0, val)
+    KSR.dbg(string.format("lrem[%s] all [%s] %s\n",
+            v.key, val, tostring(res)));
+    if self.client:llen(v.key) == 0 then
+        self:clear(v.key)
+    end
+
+    val = v.key .. separator .. val_base
+    res = self.client:lrem(v.callid, 0, val)
+    KSR.dbg(string.format("lrem[%s] all [%s] %s\n",
+            v.callid, val, tostring(res)));
+    if self.client:llen(v.callid) == 0 then
+        self.client:del(v.callid)
+    end
+end
+
+function NGCPPush:clear(key)
+    if not self:_test_connection() then
+        self:_connect();
+    end
+    local res = self.client:del(key)
+    KSR.dbg(string.format("del[%s] %s\n", key, tostring(res)));
+end
+
+--function helper for result
+--taken from luasocket page (MIT-License)
+local function build_w_cb(t)
+    return function(s,len)
+        table.insert(t, s)
+    return len,nil
+    end
+end
+
+--function helper for headers
+--taken from luasocket page (MIT-License)
+local function h_build_w_cb(t)
+    return function(s,len)
+        --stores the received data in the table t
+        --prepare header data
+        local name, value = s:match("(.-): (.+)")
+        if name and value then
+            t.headers[name] = value:gsub("[\n\r]", "")
+        else
+            local code, codemessage = string.match(s, "^HTTP/.* (%d+) (.+)$")
+            if code and codemessage then
+                t.code = tonumber(code)
+                t.codemessage = codemessage:gsub("[\n\r]", "")
+            end
+        end
+        return len,nil
+    end
+end
+
+local function postfields(data)
+    local str = ""
+    for k, v in pairs(data) do
+        str = str .. string.format("%s=%s&", k, curl.escape(v))
+    end
+    return str:sub(1, -1)
+end
+
+function NGCPPush:request(postdata)
+    local ret = {headers={}}
+    local response_body = {}
+    local headers = {
+        'Content-Type: application/x-www-form-urlencoded',
+    }
+    self.c:setopt(curl.OPT_VERBOSE, 0)
+
+    self.c:setopt(curl.OPT_SSL_VERIFYHOST, 0)
+    self.c:setopt(curl.OPT_SSL_VERIFYPEER, 0)
+    self.c:setopt(curl.OPT_HTTPHEADER, headers)
+    self.c:setopt(curl.OPT_URL, self.config.url)
+    self.c:setopt(curl.OPT_HEADERFUNCTION, h_build_w_cb(ret))
+    self.c:setopt(curl.OPT_WRITEFUNCTION, build_w_cb(response_body))
+    self.c:setopt(curl.OPT_POSTFIELDS, postfields(postdata))
+    self.c:perform()
+
+    if curl.close then
+       self.c:close()
+    end
+    ret.body = table.concat(response_body)
+    return ret
+end
+
+return NGCPPush