Thursday, March 31, 2016

Hystrix

Latency tolerance, fault tolerance and monitoring for distributed systems.
https://github.com/Netflix/Hystrix/wiki

JSON Web Token (JWT)


Other links:

LMAX Disruptor - High performance parallel event processing in Java

  • Multicast.
  • Event pre-allocation.

  • https://github.com/LMAX-Exchange/disruptor

    Tuesday, March 29, 2016

    OpenLayers 3



    Review
    Pros
    • Map rotation.
    • Large SRS support.
    • Reprojection.
    • Accurate (pixel-perfect) hit test.
    • RTree-indexed features.
    • Drawing optimizations (geometry simplification and clipping).
    • Wider support of map sources including OGC protocols.
    • Styling/symbolizers.
    • API compatible WebGL renderer (lines not supported).
    • No plugins required: built-in clustering, edition, heatmap and many other features.
    • Async rendering with "Beforeoperations”, “postcompose” y “postrender” hooks.
    Cons
    • Large API.
    • Still changing.
    • Code size.
    Resources
    Books

    Minimal Angular 2 seed

    SystemJS, TypeScript and NPM:
    https://github.com/jhades/ng2-minimal

    SystemJS, TypeScript, NPM and Gulp:
    https://github.com/angular/angular2-seed/tree/systemjs

    According to this article it should be a good starting point while angular-cli gets matured.

    Tuesday, March 15, 2016

    QlikView extensions

    Definition.xml

    <ExtensionObject PageHeight="" PageWidth=""/>
    • PageWidth: maximum number of columns to retrieve.
    • PageHeight: maximum number of  rows to retrieve.
    Data Object

    • PageSize.x:  current page column count (maximum is PageWidth).
    • PageSize.y: current page row count (maximum is PageHeight).
    • TotalSize.x: total number of columns on the data set.
    • TotalSize.y: total number of rows on the data set.
    Selection
    You can use the SearchColumn, SelectValuesInColumn or SelectTextsInColumn API methods.

    this.Data.SelectTextsInColumn(0, true, value);

    You can only make selections in the dimensions that are exposed to the extension.
    The extension functions like any chart in QlikView meaning that it can only select in the underlying hypercube

    References

    Thursday, March 10, 2016

    Vert.x



    • Asynchronous programming model.
    • Multi-reactor (one ore more event loops).
    • Polyglot: Java, JavaScript, Groovy, JRuby, Scala, ...
    • Verticles: processing units. Akka/Actor similarities.
    • Worker Verticles: blocking code.
    • Modules: reusable Verticle set with isolated classloader.
    • Local/clustered Shared Map.
    • Local/clustered Event Bus.
    • HA (auto-deploy of failed Verticles on other nodes).
    • Hot deployment (auto-reload on development).
    • Light with minimum dependencies: Netty, Jackson & Hazelcast.
    • Deployment: fat JAR or minimal Vert.x container.
    • Fast: https://www.techempower.com/benchmarks/#section=data-r12&hw=peak&test=json.