Posts
Twilio Call Status StateChart
I was not familiar with SIP states during the integration of VoIP products such as twilio, plivo and sinch. I am still confused about the state changes after reading documents. Here try to visualize the state change and help me to remember it. The state chart is based on my understanding. It is not necessarily correct. It is just for my reference.
QueuedInitiatedRingingAnsweredInProgressCompletedBusyNoAnswerCanceledFailed
Posts
Unit 1: Experimental Chemistry
Measurement Physical properties
SI Units
Other Common Units
Common measuring apparatus
Name
Symbol
time
second
s
hour (h)
minutes(min)
day
digital stopwatch
analogue stopwatch
mass
kilogram
kg
gram(g)
tonne(t)
Posts
Asciidoc diagram samples of UML
PlantUML Diagram Class diagram—​Relations between Class:
Type
Sysmbol
Extension
<!--
Composition
*--
Aggregation
o--
Asciidoc UML sample
Class01Class02Class03Class04Class05Class06Class07Class08Class09Class10 PlantUML sample
Class01Class02Class03Class04Class05Class06Class07Class08Class09Class10
Posts
Asynchronization is hard to implement
Asynchronization is very hard. It brings benefits with several catches for backend programming. Here is serveral catches and respective solutions. However all those will increase the cost of developments.
Hard to debug and trace As the process breaks down to serveral asynchronious subprocesses, it is very difficult to relate all information of the process when something goes wrong. An extra overhead correlation Id is needed to adopt to ameliorate this issue.
Posts
Why I start to write again
I read a lot of blogs. However I rarely wrote my blogs about my thoughts and learning experiences as I thought those are lack of originality.
I changed my mind after I learned more than ten thousand words using anki and memrise in the past 2 years. A writing can serve multiple purposes even lack of originality and thorough thought. Here is a list of those purposes:
Deepen my understanding in the topics and improve efficiency of learning
Posts
Diagrams samples
Ditaa
0 start1 q scans from start to end.....endrest of theallocated memory.....n