Description: Information System Practice Notes series is the author in peacetime research and development has encountered the size of the problem, perhaps simple and subtle, but often is often encountered problems. The author is more typical of which to collect, describe, summarize and share.
Absrtact: This article describes the interface between the information system or the platform which the author has contacted, and exhaustive to share it.
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Series of essays Directory: Information System Practice notes (http://www.cnblogs.com/taichu/p/5305603.html)
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In applications that revolve around maps (GIS), there are a number of third-party platforms that need to be accessed, which is more or less mentioned in previous shares.
The "Bayonet platform", as a proprietary platform closely related to the application of maps, is often provided exclusively to public security, traffic police or professional users by third party vendors.
But this supplier itself does not have the ability to be a powerful integrated application platform, and this is our strength, so the business around the GIS, also certainly includes docking "bayonet platform" one.
The following is a very specific description of the relevant content, including: The business situation of the bayonet platform, the form of docking platform, the specific problems encountered in the docking, such as some examples of analysis and other content.
A. Business situation of the bayonet platform :
A1 Bayonet Platform Introduction
Bayonet Platform It is a software platform and has many front-end devices (of course, these front-end devices may also be governed by another dedicated device platform and connected to the bayonet platform).
The front-end devices in the bayonet platform are cameras that are mounted at the intersection gantry and can be instantly highlighted, regardless of the night or morning. In addition to intersections, it is possible to have a camera on an elevated toll station or a gantry on an entrance to the driveway. These cameras are usually one or more "guards" a lane, each lane is one-way traffic. So the general two-lane, four-lane, or even six-lane road, at the intersection of the place, you will see the gantry mounted on a lot of cameras, flash one after the clap of photos, not necessarily illegal photos, there are normal circumstances of the photo.
Users of the bayonet platform are generally public security or traffic police departments, they need to collect information on these bayonet, in order to manage traffic and maintain public order. In fact, different front-end devices (Camera, abbreviated CAM) belong to different departments, but because the information between the departments is not fully interoperable, there must be a waste of resources exist.
A2 Card Opening platform business
- Check the history of the car's past (business platform platform for active query card port platform);
- Bayonet arming and disarming;
- The distribution of the real-time record of the bayonet (the bayonet platform actively pushes to the business platform);
- The arming and disarming of the license plate blacklist;
- License plate blacklist alarm distribution (bayonet platform actively pushed to the business platform);
* Here only to list and compare the typical basic business, there are some infrequently used not listed, the reader can do their own research;
About the bayonet subscription, unsubscribe and real-time record distribution: The business platform can be based on the user's needs, through the open interface of the bayonet platform, to the bayonet platform to subscribe to the alarm, that is, arming, can be targeted at a bayonet a real-time arming. Then once the arming is successful, all the real-time information of the bayonet passing through the car (vehicle information including, license plate, body color, whether speeding, photos, etc.) will be sent to the subscribed business platform and forwarded to the user for real-time viewing. Do not need to follow the interface to unsubscribe (disarm). This is similar to the classic subscription distribution model inside the design pattern. In addition, the distribution of the interface can be provided by the business platform, or can be provided by the bayonet platform, which depends on how the platform between the docking (see: Information System Practice notes 4-platform docking some thinking);
About blacklist arming, disarming and warning distribution: It's sort of like a bayonet subscription, but it's for a certain time period of a license plate A to be armed, to see if the two blacklisted cars appear. If it does, grab it, take a photo and alarm to the business platform (upper platform), and trigger more complex business and rule applications.
B. Overview of the details of the docking-bayonet platform :
Platform docking overview are in (Information systems Practice notes 4-platform docking Some thinking) mentioned, no longer described, here is only a list of details for the relevant professional reference;
- Business related to "bayonet arming":
- Bayonet Device Query (call direction: Business platform-and bayonet platform): This is important, is the basis of some of the business and interface of the bayonet, it generally returns a long list of bayonet devices, which is common.
- Bayonet Subscription interface (call direction: Business Platform---bayonet platform) : Generally, there are many forms of webservice (also popular restful); You can export Java classes directly from WSDL using tools such as axis, and add business, relatively simple and clear, (if it is a specific private interface, such as the private proprietary format of the socket interface, the two sides contract the binary byte format or some of the advanced strings string, or even XML format, so that requires specialized parsing code, a little bit of trouble, But also good, execution speed faster);
- request typically contains fields: "Bayonet ID, subscription start time, subscription end time, business platform tag, and so on"
- Business platform tag field: Yes, considering the bayonet Platform and a number of business platforms are connected, depending on the bayonet platform to do well, the design staff is not high. Without consideration, the experts of both sides should mention it when negotiating the interface. If the bayonet platform is considered, and does not need to add the "Business platform tag", it can be based on the call information or IP to differentiate, natural better, and stronger!
- start and End field: if both the subscription and the unsubscribe are in effect immediately, the start and end time can be omitted, the default current time;
- response generally contains fields: "Subscription number ID,ERRORNBR , ErrorMsg, and so on "
- " Subscription id "field: For unsubscribe
- Business Competency Survey: Although the interface is clear, the business capability of the bayonet platform Also need to understand, to cite only one example for reference: such as "arming start and end time", is it allowed to exceed "100 years" between? may not take so long, but this is to be considered, according to business capabilities, user interface GUI above need to do "match" restrictions! Such details are numerous, and the system experts on both sides must discuss it clearly. It is best to have an organizational process asset like interface design checklist to help, as we share in the follow-up, when it comes to agile development.
- Bayonet Unsubscribe Interface (call direction: Business Platform---bayonet platform): General and arming subscriptions symmetric, form and model consistent.
- The request generally contains fields: "Subscription number ID, etc.";
- Response generally contain fields: "errornbr,errormsg, etc.";
- Card exit record escalation (call direction: Bayonet Platform--business platform): in the period of the effective start-up time of the subscription, or in the case of real-time efficiency, the general guardian of the card port has a car situation, the relevant information to the business platform. The use of more is the HTTP protocol post, with custom fields, generally with the "|" To separate, the entire string as value, put in the Key=value format, which is a common means.
- Request generally contains fields: "Bayonet ID, bayonet name, time of vehicle, license plate information, vehicle type, photo URL, etc.";
- response generally contains fields: "Errornbr,errormsg, et cetera "; (normally 200OK is returned in accordance with the HTTP protocol, and if there is an error, it should be returned in accordance with the Protocol, no longer burdensome)
- Bayonet Drive record query (call direction: Bayonet Platform--business platform): In addition to proactive push means, actively querying historical data is another means. Many ways, such as platform docking and interface definition, such as:
- Business platform directly query the card port db (not very good, the business platform will be back on performance, security and other additional issues);
- The business platform calls the interface of the history query record of the bayonet platform directly (this method is most formal and good!) ）
- The Business Platform transmits SQL query statements to the bayonet platform (not very well, but sometimes because of the third-party platform situation first, but only then)
- Specific interface because of various forms, do not explain;
- Business related to "bayonet arming":
- Blacklist Subscription interface (call direction: Business Platform---bayonet platform): form similar to bayonet subscription, slightly;
- blacklist unsubscribe Interface (call direction: Business Platform---bayonet platform): slightly;
- blacklist over-vehicle record escalation (call direction: Bayonet Platform--business platform): in essence, is the vehicle information, support the departure condition is not the Guardian "bayonet", but the Guardian "license plate" just;
- blacklist record query: also similar, slightly;
C. Internal bayonet model of the business platform :
here a little mention of the business platform internal to the bayonet model of the establishment, arrangement and processing, involving demand analysis, system design and other content, only to mention the outline for reference;
- Business systems must not have a dedicated internal "bayonet model" to correspond to the business of the bayonet, otherwise the code is too bad;
- The "Bayonet model" concept is divided into several pieces: a list of bayonet devices; a piece of a blacklist subscription entry; The actual vehicle record information piece; historical vehicle information piece;
- The design of "bayonet model" is divided into: Bayonet device cache, bayonet subscription and blacklist subscription cache, real-time cache of vehicle history, table (persistence) of historical vehicle record;
- "Bayonet Model" business rules: around the above several concepts, as well as the concept of landing data interface, such as cache,table, you can write the business of Pseudo-code;
- Abstract: Through the above processing, shielding the business platform for different bayonet platform differences, because different bayonet platform has a lot of different:
- Business functions are different: Some have a blacklist, some only bayonet, and some no real-time push, only historical query, and so on;
- Business restrictions are different: Some start and end time can only support 50, some longer, some return device list will be automatically paged, some have a limited length, and so on;
- The business ability is different: Some push fast, can support 10 seconds a, even faster, even can be configured, some can not be configured, some very slow, and so on;
- Summary: In fact, the docking card platform, can be abstracted as a docking of a "competency platform", then naturally to the ability to set {capacity 1, capacity 2, ...} Peel clear, and then design internal models to support these capabilities in multiple layers, while taking into account the abstraction and degree of implementation of these capabilities are different, and then consider different docking scenarios.
Summarize:
Platform docking is a huge macro, but meticulous work, no more than 5-10 years of experience, down, not good.
and categories of various industries of different needs, platforms, docking style, changing, the situation is complex and changeable,
Often absolutely excellent frame design, pattern design, aspect programming, scene deduction, but also difficult to solve all problems,
Sometimes even the human problem, it is particularly regrettable. This refers to the development process and development management issues, next time maybe we have a chance to talk about this old problem.
Information System Practice notes 7-docking bayonet platform details
