Skip to Content
Last modified by Erik Bakker on 2024/08/26 12:37
From version 45.1
edited by Erik Bakker
on 2022/10/31 10:43
Change comment: There is no comment for this version
To version 30.2
edited by Erik Bakker
on 2022/06/10 13:23
Change comment: Update document after refactoring.

Summary

Details

Page properties
Title
... ... @@ -1,1 +1,1 @@
1 -Volume Mapping (On-premise)
1 +novice-file-based-connectivity-characterset
Default language
... ... @@ -1,1 +1,0 @@
1 -en
Content
... ... @@ -1,9 +1,11 @@
1 1  {{container}}{{container layoutStyle="columns"}}(((
2 +In some cases, you want to treat each unique part of your input file as its message instead of processing the complete file as its message. In this microlearning, we will learn how you can process a (large) file on a per-line basis.
2 2  
3 -When you need to read and write files from an on-premise disk, you need to know the path in which the data is stored and make sure that the docker container in your runtime(s) running has access to this path. There are several ways of dealing with this challenge. First, this microlearning will discuss the various alternatives and best approaches in these scenarios.
4 -
5 5  Should you have any questions, please contact [[academy@emagiz.com>>mailto:academy@emagiz.com]].
6 6  
6 +* Last update: May 31th, 2021
7 +* Required reading time: 7 minutes
8 +
7 7  == 1. Prerequisites ==
8 8  
9 9  * Basic knowledge of the eMagiz platform
... ... @@ -10,91 +10,93 @@
10 10  
11 11  == 2. Key concepts ==
12 12  
13 -This microlearning centers around learning how to set up your volume mapping correctly so you can exchange file-based data on-premise.
15 +This microlearning centers around learning how to process an incoming file per line.
14 14  
15 -By volume mapping, we mean: Creating a configuration through which the docker container can read and write data on a specific path on an on-premise machine.
17 +By processing per line, we mean: Splitting up the input into discernable pieces that each will become a unique message
16 16  
17 -There are several options for volume mapping for your on-premise machine.
18 -* Volume
19 -* Bind mount
20 -* Temporary file system
21 -* Named pipe
19 +* Easy way of reading a file line by line and sending it to eMagiz (Low on memory)
20 +* Ability to process each line based on distinctive logic that is relevant on line level
21 +* Can be used for flat file as well as XML input files
22 22  
23 -== 3. Volume Mapping (On-premise) ==
23 +== 3. Processing a File per Line ==
24 24  
25 -When you need to read and write files from an on-premise disk, you need to know the path in which the data is stored and make sure that the docker container in your runtime(s) running has access to this path. There are several ways of dealing with this challenge. First, this microlearning will discuss the various alternatives and best approaches in these scenarios.
25 +In some cases, you want to treat each unique part of your input file as its message instead of processing the complete file as its message. In this microlearning, we will learn how you can process a (large) file on a per-line basis.
26 26  
27 -There are several options for volume mapping for your on-premise machine.
28 -* Volume
29 -* Bind mount
30 -* Temporary file system
31 -* Named pipe
27 +To make this work in eMagiz you need to navigate to the Create phase of eMagiz and open the entry flow in which you want to retrieve the file to a certain location. Within the context of this flow, we need to add functionality that will ensure that each line is read and processed separately and will become its unique message. To do so first enter "Start Editing" mode on flow level. After you have done so please add a file item reader message source to the flow. We will use this component to read and process our input file on a per-line basis.
32 32  
33 -Below we will explain the differences between the various options available for your volume mapping. But before we do, we first explain how to set up this configuration within eMagiz. Then, you must navigate to Deploy -> Architecture on the model level. In this overview, you can access the Volume mapping per runtime deployed on-premise. To do so, you can right-click on the runtime to access the context menu.
29 +The first step would be to define the directory from which we read our messages. As always reference to the directory with the help of a property.
34 34  
35 -[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-volume-mapping-on-premise--volume-option-context-menu.png]]
31 +[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-processing-a-file-per-line--file-item-reader-directory.png]]
36 36  
37 -When you click this option, you will see the following pop-up. In this pop-up, you can define the machine-level and runtime-level volumes. More on that later. This is the starting point for configuring your volume mapping. We will walk through each available option and explain how they work and should be configured.
33 +Secondly, just as when reading the file as a whole ensure that you use a filter to retrieve only the correct files from the directory.
38 38  
39 -[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-volume-mapping-on-premise--volume-mapping-pop-up.png]]
35 +=== 3.1 Item reader Type ===
40 40  
41 -{{info}}Note that you should be in "Start editing" mode to make any changes to the configuration of your volume mapping.{{/info}}
37 +Now it is time to select our Item reader Type. As the help text of the eMagiz component suggest there are two choices with this component. The first (and most frequently used) option is the Flat file item reader. With this option, you can read each line within the flat file input file and output is at a separate message. The second option is called the Stax event item reader. With this option, you can read your input XML and output messages on a per-record basis.
42 42  
43 -=== 3.1 Volume ===
39 +[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-processing-a-file-per-line--item-reader-type-options.png]]
44 44  
45 -The first type available to you is Volume. With this option you create one or more folders on docker that is relevant for that runtime to read and/or write **persistent** data. To configure this type you need to link the runtime volume to a machine volume that you can create within the same pop-up. This means that you can re-use a "Machine volume" over multiple runtimes (i.e. containers).
41 +Based on your choice the exact configuration will differ.
46 46  
47 -So, at first we open the tab called "Machine volume". By pressing the "New" button we can define a new "Machine volume". In the pop-up that follows we can define the name of a machine volume and tell whether the volume already exists on your docker installation or not.
43 +==== 3.1.1 Stax Event Item Reader ====
48 48  
49 -[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-volume-mapping-on-premise--machine-volumes-configuration.png]]
45 +For the Stax event item reader, you need to define the name of the element on which you want to split the XML and define whether you want to throw an error in case no such element exists in the input file (By (de)selecting the option Strict). The default setting of eMagiz is advisable for this option.
50 50  
51 -Once you have done so we press "Save" and switch back to the "Runtime volumes" tab. In here we press the "New" button to create a new "Runtime volume". In the pop-up that follows we first need to select the Type we want to use. For this example we use the type called "Volume". Based on your selection the relevant input fields will change.
47 +[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-processing-a-file-per-line--stax-event-item-reader-config.png]]
52 52  
53 -[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-volume-mapping-on-premise--runtime-volumes-configuration-type-volume.png]]
49 +==== 3.1.2 Flat File Item Reader ====
54 54  
55 -The first thing we need to select is the "Machine volume". Once we have selected our "Machine volume" we need to select the Target that is specific for this runtime. This target defines the second part of the path to which the runtime will gain access. For example, when you fill in "/target" we can combine this with the "Machine volume" name to arrive at the correct directory from which eMagiz needs to read data (or write data to). So in our case this would be "/file-directory/target."
51 +For the Flat File item reader, there are some more choices and configurations to be made. There are three options you can choose from:
52 +- Pass through line mapper
53 +- Default line mapper
54 +- Pattern matching composite line mapper
56 56  
57 -The last setting we need to configure is to define which rights we will grant our runtime on the volume we are creating. The default setting is read/write rights for the runtime which is sufficient in most cases. The result of following these steps will be the following.
56 +Each of these options has some advantages and disadvantages. Adhering to the best practices of eMagiz (i.e. no transformation in the entry) the best option would be to use the pass-through line mapper. As the name suggests this option does nothing except give a string back to the flow on a per line basis. However, choosing this option means that the actual transformation from that string to XML needs to happen later in the process (most likely in the onramp) with the help of a flat-file to XML transformer (more on that component in a later course).
58 58  
59 -[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-volume-mapping-on-premise--runtime-volumes-configuration-type-volume-filled-in.png]]
58 +The other two options transform the input line into an XML output. So you win one step in the process. However, no standard eMagiz error handling is advisable when you start transforming data within the entry. So in case, something goes wrong to analyze the error will become more difficult. Furthermore, another potential disadvantage is that when one line fails the processing of the rest of the file also halts.
60 60  
61 -{{warning}}Note, that when you use the Volume option the external system with which you exchange data on-premise via a file based method need to be able to write or read the data from the volume (i.e. directory) you have configured in Docker. Should this be a problem the Bind mount alternative discussed below should be considered.{{/warning}}
60 +For the remainder of this microlearning, we will assume that the option pass through line mapper is chosen.
62 62  
63 -=== 3.2 Bind mount ===
62 +[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-processing-a-file-per-line--flat-file-item-reader-passthrough.png]]
64 64  
65 -An alternative option to read and write **persistent** data is to use the "Bind mount" option avaiable. In general we advice to use the "Volume" option because they have better performance and bind mounts are dependent on the directory structure and OS of the host machine. Having said that not all external systems can adapt to this that easily. That is why the "Bind mount" option can be of interest in your use case.
64 +As you can see on the Basic level we are done. However, it is always good to check out the settings on the Advanced tab, especially in this case, to see if there are additional configuration options that could benefit us. The setting of most interest, in this case, is the Lines to Skip setting (default setting is 0). With this setting, you can define whether or not you want to process the header line(s) that exists within your input file. The remainder of the settings is (in most cases) good the way eMagiz has set them up.
66 66  
67 -To configure a "Bind mount" you need to define a source and a target directory that are linked to each other. The source directory defines the directory on your local system (that might already be in use currently to exchange files). The target directory defines a directory on your docker installation that can be accessed by the runtime.
66 +[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-processing-a-file-per-line--flat-file-item-reader-passthrough-advanced.png]]
68 68  
69 -=== 3.3 Temporary file system ===
68 +=== 3.2 Poller ===
70 70  
71 -=== 3.4 Named pipe ===
70 +Now that we have selected and configured the item reader type it becomes time to fill in the last part of the configuration, the poller. For polling eMagiz offers three options:
72 72  
73 -The named pipe option can be selected but we yet have to see a valid use case within the context of eMagiz for using this option. Therefore we won't discuss this option further in this microlearning.
72 +- Fixed Delay Trigger
73 +- Fixed Rate Trigger
74 +- Cron Trigger
74 74  
76 +Of these options, the cron trigger is used most frequently in eMagiz. The reason being is that you can define this option via a property that you can alter without having to alter the flow version in Create.
77 +
78 +[[image:Main.Images.Microlearning.WebHome@novice-file-based-connectivity-processing-a-file-per-line--poller-config.png]]
79 +
80 +After finishing all these configuration steps we can press Save to save our work and ensure that we can process the input file on a per-line basis.
81 +
75 75  == 4. Assignment ==
76 76  
77 -Configure an entry in which you build the archiving and the clean up of the archiving.
84 +Configure an entry in which you define the component and configuration needed to process a file on a per-line basis.
78 78  This assignment can be completed with the help of the (Academy) project that you have created/used in the previous assignment.
79 79  
80 80  == 5. Key takeaways ==
81 81  
82 -* Archiving is used for audit purposes
83 -* Archiving is used for retry scenarios
84 -* Ensure that data is cleaned after a retention period to keep in control of the data
85 -* Don't forget the max messages per poll
89 +* Easy way of reading a file line by line and sending it to eMagiz (Low on memory)
90 +* Ability to process each line based on distinctive logic that is relevant on line level
91 +* Can be used for flat file as well as XML input files
92 +* Try to avoid complex transformations within the entry
86 86  
87 87  == 6. Suggested Additional Readings ==
88 88  
89 -If you are interested in this topic and want more information on it please read the help text provided by eMagiz and check out the following store content:
96 +There are no suggested additional readings on this topic
90 90  
91 -* [[File Archiving>>doc:Main.eMagiz Store.Accelerators.File Archiving.WebHome||target="blank"]]
92 -* [[Delete Folder(s)>>doc:Main.eMagiz Store.Accelerators.Delete Folder(s).WebHome||target="blank"]]
93 -
94 94  == 7. Silent demonstration video ==
95 95  
96 96  This video demonstrates how you could have handled the assignment and gives you some context on what you have just learned.
97 97  
98 -{{video attachment="novice-file-based-connectivity-characterset.mp4" reference="Main.Videos.Microlearning.WebHome"/}}
102 +{{video attachment="novice-file-based-connectivity-processing-a-file-per-line.mp4" reference="Main.Videos.Microlearning.WebHome"/}}
99 99  
100 100  )))((({{toc/}}))){{/container}}{{/container}}