1 00:00:00,000 --> 00:00:12,866 Hi, Let us understand how to modify scope using 'with' . I can create a block of restricted scope using with 2 00:00:12,866 --> 00:00:16,766 keyword. I can have a with and then a pipeline where 3 00:00:16,766 --> 00:00:20,899 It's going to evaluate a condition or it's going to read a collection of values. 4 00:00:20,900 --> 00:00:27,900 And once the condition is evaluated, it's going to execute the collection of statements within the block. 5 00:00:27,900 --> 00:00:34,633 And the value that got evaluated using the pipeline will be available or can be used only within that 6 00:00:34,633 --> 00:00:38,433 specific block, within the restricted scope. 7 00:00:38,433 --> 00:00:42,499 Let us understand, using a small demo. Let me get into the chart that we had created. 8 00:00:42,500 --> 00:00:45,333 Let me add some sample values. 9 00:00:45,333 --> 00:00:47,566 I'm going to edit the values file. Here 10 00:00:47,566 --> 00:00:55,099 I'm going to add a key called tags and it's going to have a collection of key value pair like machine as key 11 00:00:55,100 --> 00:00:56,900 and frontdrive as value 12 00:00:56,900 --> 00:01:01,466 Like that I have some key and value pair within the key tags. 13 00:01:01,466 --> 00:01:03,366 So this is something like a map. 14 00:01:03,366 --> 00:01:06,999 Or we can visualize this as a collection as well. 15 00:01:07,000 --> 00:01:10,733 Now I'm going to change the template. So within the template 16 00:01:10,733 --> 00:01:21,166 I'm going to add the with condition and I'm going to read the values.tags, observe the space whitespace. 17 00:01:21,166 --> 00:01:26,699 So I do have two white spaces and the condition is getting started over here. 18 00:01:26,700 --> 00:01:34,100 And the key value pair, I am adding it in the same indent where I am doing the evaluation with 19 00:01:34,100 --> 00:01:39,000 I am adding the keyword then I'm getting the values.tags 20 00:01:39,000 --> 00:01:44,433 So all the values within the tags will be available only within this specific scope and within 21 00:01:44,433 --> 00:01:48,366 this scope, the global within this specific scope 22 00:01:48,366 --> 00:01:51,966 The builtin objects will also be not accessible. 23 00:01:51,966 --> 00:01:53,899 We will do that as a separate demo. 24 00:01:53,900 --> 00:01:58,900 Now I'm going to use this specific values.tag as a with and directly 25 00:01:58,900 --> 00:02:06,300 I can access.machine because the parent scope of this particular block is tags. So within the tags 26 00:02:06,300 --> 00:02:15,033 I can access the machine, rack, dry and Vcard. Let me go ahead and execute the dry run. 27 00:02:15,033 --> 00:02:18,833 And the entire content of this particular YAML file as well as the commands 28 00:02:18,833 --> 00:02:24,833 It will be added along with the resources so directly you can download and start using them. 29 00:02:24,833 --> 00:02:28,499 Now, let me go ahead and do a dry run. 30 00:02:28,500 --> 00:02:33,933 Now, let me go ahead and do a dry run. 31 00:02:33,933 --> 00:02:42,966 So the condition got evaluated and it read the Values SSD, frontdrive, 4c and 8g and it got printed here. 32 00:02:42,966 --> 00:02:48,899 Now let's go ahead and try another scenario of how the indent can be used. 33 00:02:48,900 --> 00:02:53,500 Getting into the template here the same values from the tags 34 00:02:53,500 --> 00:03:00,300 I'm going to read and add it as a part of the labels. 35 00:03:00,300 --> 00:03:05,300 This is another good example to understand how the white space should be used, so within labels, I 36 00:03:05,300 --> 00:03:09,000 am going to have a set of labels that is first, second and third. 37 00:03:09,000 --> 00:03:14,266 The values will be picked because I am using with within this particular block. 38 00:03:14,266 --> 00:03:20,499 So it's going to read all the values from the tags and all the references within this particular block 39 00:03:20,500 --> 00:03:23,933 will be to that particular tags scope only. 40 00:03:23,933 --> 00:03:27,066 So within the tags, it's going to read machines, rack and dry. 41 00:03:27,066 --> 00:03:34,199 And with the same indent, it's going to print the values, let me go ahead and do a dry run. 42 00:03:34,200 --> 00:03:37,366 The dry run will be very useful for debugging as well. 43 00:03:37,366 --> 00:03:44,799 So within labels, I do have three labels with the key and value and it got added. So the whitespace 44 00:03:44,800 --> 00:03:46,900 Indent is very, very important. 45 00:03:46,900 --> 00:03:51,500 Now, let's go ahead and add something which is not there within the scope. 46 00:03:51,500 --> 00:03:58,633 So within this specific block, I'm going to access the builtin object release.name 47 00:03:58,633 --> 00:04:03,566 So within the tags I will not have anything with release or name. 48 00:04:03,566 --> 00:04:06,966 So there should not be any value getting printed for this. 49 00:04:06,966 --> 00:04:15,399 Let me go ahead and do a dry run. Its not getting any value. 50 00:04:15,400 --> 00:04:22,633 So the yaml it turned out to be a not valid template, and there are some options to solve this 51 00:04:22,633 --> 00:04:28,266 particular problem and definitely there will be a need to access the builtin objects within the 52 00:04:28,266 --> 00:04:31,766 blocks and we can solve it using variables. 53 00:04:31,766 --> 00:04:34,799 We will be discussing about variables in future lecture. 54 00:04:34,800 --> 00:04:39,033 And I can go ahead and add this particular release name. 55 00:04:39,033 --> 00:04:43,233 outside the restricted block and that should work. 56 00:04:43,233 --> 00:04:49,099 If I add this particular release name outside this restricted block 57 00:04:49,100 --> 00:04:56,300 this should work. Let me go ahead and do a dry run. 58 00:04:56,300 --> 00:04:59,400 And yes, it's able to read the release name. 59 00:04:59,400 --> 00:05:07,200 So basically within the restricted block, we cannot use the values from other scope or even the builtin objects. 60 00:05:07,200 --> 00:05:11,900 We cannot access and that should be accessed using the variables. 61 00:05:11,900 --> 00:05:15,133 And this restricted block will be very useful whenever I wanted to 62 00:05:15,133 --> 00:05:17,533 iterate over a given set of values 63 00:05:17,533 --> 00:05:23,666 or given set of arrays it will be very useful so that I can work only on that restricted set of values.