angularjs - Improving mobile aps client server communication efficiency and data availability in offline mode -

-

my question how store data once received online , still can processed after mobile device got offline and/or restarted. i'm using angularjs ionic (phonegap) building apps. question not explicitly adressing these technologies.

best practices, patterns or algorythms helpful me or useful articles or key words.

1) simple challenge make app more user-friendly making functionality usable not if device online in offline mode. in case implies have make last fetched online data available later use (while device offline , after restarting device!).

2) bit more difficult reduce communication costs synchronizing server side changed data when device reconnects internet.

3) entities can produced on client side while device offline , must synchronized server too. there no potential risks of conflicts because users don't share entities write access.

4) use googles , apples push services inform devices newer entity versions, should updated on client side. polling isn't needed.

client side technologies: javascript, angularjs framework, ionic framework, sqlite (websql) or indexeddb, phonegap (cordova)

server side technologies: java ee, jpa, mysql

data format , communication: json on rest / http, googles , apples push services server-to-client messaging

1) store needed data inside local sqlite database, , pull out when app starts/resumes.

2)in mysql database need table creates new entries when update/change/create content. need store id , timestamp (maybe boolean value if content deleted).

on device make request server send data table , compare locally stored data. if there new id or timestamp has change make new request pull updated data.

3)store created data locally flag isn't synced server. when device goes online again check not synced flags , send data server identifier know device comes , save it.

4)see 2)

you make java script checks every x minutes updated entries , send automatic push notification it. need 2 tables, 1 newest updates , 1 updates got pulled device(just id's , timestamps, not data).

i hope helpful, if new comes mind update answer.


Comments

Post a Comment

Popular posts from this blog

python - No exponential form of the z-axis in matplotlib-3D-plots -

-
Image
i have similar problem described in how prevent numbers being changed exponential form in python matplotlib figure : i don't want (in special case) weird scientific formatting of axis. problem different have problem @ z -axis. 2-d plots can use ax.get_yaxis().get_major_formatter().set_useoffset(false) . , there no function ax.get_zaxis() what use format z -axis same way? edit: example: from mpl_toolkits.mplot3d import axes3d import numpy np import sys import matplotlib import matplotlib.pyplot pyplot def func(xi, ti): res = 10e3 + np.cos(ti) * np.sin(xi) return res if __name__ == '__main__': timespacing = 20 timestart = 0 timeend = 1 time = np.linspace(timestart, timeend, timespacing) widthspacing = 50 widthstart = 0 widthend = 3 width = np.linspace(widthstart, widthend, widthspacing) reslist = [] matplotlib.rcparams['legend.fontsize'] = 10 fig = pyplot.figure() ax = fig.gca(projection = '3d...
Read more

php - Best Light server (Linux + Web server + Database) for Raspberry Pi -

-
i install web server database on raspberry pi (little computer). computer has 1gb ram. i want know best combination: linux distribution , web server , dbms run local server multiple users minimal latency, use php on server. , best settings performance , not have bugs (memory usage, disable plugin, disable service, etc)? i thought light debian , lighttpd server , sqlite database. solution? i think lighttpd + sqlite great choice. linux distro, debian @ centos or tiny core linux , although i'm not sure of compatibility pi. obviously, can't go wrong raspbian if want use in production , more stable performance, few more pi's , set them in cluster .
Read more

c# - "Newtonsoft.Json.JsonSerializationException unable to find constructor to use for types" error when deserializing class -

-
i developing app in xamarin android. have splash screen serialize class , pass mainactivity using intent . when try deserialize in mainactivity error message : "serializationexception unable find constructor use types" serialization : void loaddata() { currency currency = new currency(this); intent = new intent(this, typeof(mainactivity)); intent.putextra("currency", newtonsoft.json.jsonconvert.serializeobject(currency)); startactivity(intent); } deserialization : cur = newtonsoft.json.jsonconvert.deserializeobject<currency> (intent.getstringextra("currency")); // error here class constructor : public currency(context context) { thiscontext = context; } i began experiencing problem after added parameter context context constructor. has caused this? how can solve it? possible serialize/deserialize class has parameters? you need have empty constructor in currency class in order deserialize it. ...
Read more