I'm new to TOML and I have several sets of a scenario where two tables are identical. Is it possible to define multiple tables with the same keys without having to repeat everything?
For example, take this TOML file for AWS SAM configuration. When using the sam local commands, the options I require are exactly the same, but I have to define them twice.
version = 0.1
[dev1.local_invoke.parameters]
profile = "dev1"
...
[dev1.local_start_lambda.parameters]
profile = "dev1"
...
[dev2.local_invoke.parameters]
profile = "dev2"
...
[dev2.local_start_lambda.parameters]
profile = "dev2"
...
I've tried the obvious things, but they don't work. I've also looked at the documentation but there is nothing obvious, though as mentioned I'm new to TOML so I may be missing something.
[dev.local_invoke.parameters]
[dev.local_start_lambda.parameters]
...
[dev.local.parameters]
...
It looks like TOML files don't support this feature as a deliberate design choice. In fact, this was discussed in more detail in issue #697.
It seems like the driving philosophy is that as soon as values in the TOML file refer to other values, it ceases to become a flat file and also becomes less readable.
As a workaround, you may be able to keep your TOML files thin-and-readable by consolidating the shared values up front and then having a separate program or script process the TOML file and delegate the repeat values.
Related
I have a really complicated system which use multiple languages and frameworks (Java Python Scala Bash). In each module I need to retrieve configuration values which are similar and change frequently. Currently I'm maintaining multiple conf files which holds lots of duplicates.
I wonder if there is out of the box RestAPI which can retrieve variables by demand from remote location.
All I manage to find by now are ways to load the entire file from remote source which is half a solution from me:
YAML.parse(open('https://link_to_file/file.yaml'))
My goal, which I fail to find a lead to it, is to make a direct call.
MyRemoteAPI.get("level1.level2.x")
P.S
YAML is not mandatory solution for me, I'm Open for suggestions.
I don't know about an out-of-the-box API, but it's fairly trivial to build. Make a service that will read the YAML file and traverse to the appropriate key. e.g. using a dynamic language like Ruby (+Rails), you could do something like
def value
config = YAML.load_file '/local/path/to/config.yaml'
render plain: config.dig(params[:key].split('.'))
end
dig essentially traverses a structure and safely returns nil if a key isn't found, so this returns the value at the "leaf" of the requested path.
You might also want to cache the structure in memory to prevent constantly reading from the file, e.g. could do something like ##config ||= YAML.parse(open('https://link_to_file/file.yaml')) or config = Rails.cache.fetch('config', expire_in: 1.hour) { ... }. And/or cache the API's HTTP response.
I'm defining my own Puppet class, and I was wondering if it is possible to have an array variable which contains a list of all files in a specific directory. I was wondering to have a similar syntax like below, but didn't found a way to make it work.
$dirs = Dir.entries('C:\\Program Files\\Java\\')
Does anyone how to do it in a Puppet file?
Thanks!
I was wondering if it is possible to have an array variable which contains a list of all files in a specific directory.
Information about the current state of the machine to be configured is conveyed to the catalog compiler via facts. These are available to your classes as top-scope variables, and Puppet (or Facter, actually) provides ways to define your own custom facts. That's a link into the Facter 3 manual, but similar applies to earlier versions. Do not overlook the rest of the Facter documentation, which has more relevant information on this topic.
On the other hand, information about the machine providing catalog-building services -- the master in a master / agent setup -- can be obtained by writing and calling a custom function. This is rarely what you actually want, but it's worth mentioning because you might one day want a custom function for some other purpose.
Is there any way to have a user defined parameter in a file and then have the dist.ini set the value for the parameter. For example, a file might contain {{$THE_ANSWER}} and the dist.ini file would provide a value like THE_ANSWER = 42? I'm pretty new to using dist::zilla to work with perl distributions, and I'm having problems understanding how it treats files as templates. There seem to be only a couple of hard-codeed parameters, varying by plugin, that can be used for any file. One such parameter is the {{$NEXT}} variable made available by [NextRelease] in the Changes file.
I read through the tutorials and searched the modules on CPAN and can't figure out if this is even possible. It is not an acceptable work-around to use the [GenerateFile] plugin to put the whole file in the dist.ini file. Besides a lack of flexibility and just plain ugliness, it doesn't seem possible to add lines with leading white-space that way.
What I would do is use a stash or plugin to store the variables. Stashes are like plugins, but they don't do anything but store data, and they can be put into your global configuration as well as your dist.ini.
[%Vars]
favorite_pie = pumpkin
Then you can get at them like this:
$zilla->stash_named('%Vars')->favorite_pie
This assumes that you've made Dist::Zilla::Stash::Vars and given it a favorite_pie attribute.
You could make a totally generic stash, though, which accepts anything as a key. For that, I'd look at the source of Dist::Zilla::Plugin::Prereqs, which allows arbitrary configuration options and shoves them into a hash attribute in its BUILDSARGS method.
You could make that Dist::Zilla::Stash::Generic, and then register it as many times as you want for different reasons:
[%Generic / Pies]
favorite = pumpkin
hated = rhubarb
firstever = quince
[%Generic / Passwords]
pause = PeasAreDelicious
google = secret
reddit = SecretPeasAreDelicious
...then, as needed, say in templates...
{{ $zilla->stash_named('Passwords')->get_var('pause' }}
If I was making a lot of files that used this sort of generic thing, I'd pass their Text::Template instance a closure called get_password like this:
get_password => sub { $zilla->stash_named('Passwords')->get_var($_[0]) }
Then your template could include:
Login with: {{ get_password("pause") }}
This answer obviously leaves some source digging for you, but I think it should point at all the pieces I'd use to do what you want.
I need to analyse several sets of data which are associated with different parameter sets (one single set of parameters for each set of data). I'm currently struggling to find a good way to store these parameters such that they are readily available when analysing a specific dataset.
The first thing I tried was saving them in a script file parameters.m in the data directory and load them with run([path_to_data,'/parameters.m']). I understand, however, that this is not good coding practice and it also gave me scoping problems (I think), as changes in parameters.m were not always reflected in my workspace variables. (Workspace variables were only changed after Clear all and rerunning the code.)
A clean solution would be to define a function parameters() in each data directory, but then again I would need to add the directory to the search path. Also I fear I might run into namespace collisions if I don't give the functions unique names. Using unique names is not very practical on the other hand...
Is there a better solution?
So define a struct or cell array called parameters and store it in the data directory it belongs in. I don't know what your parameters look like, but ours might look like this:
parameters.relative_tolerance = 10e-6
parameters.absolute_tolerance = 10e-6
parameters.solver_type = 3
.
.
.
and I can write
save('parameter_file', 'parameters')
or even
save('parameter_file', '-struct', 'parameters', *fieldnames*)
The online help reveals how to use -struct to store fields from a structure as individual variables should that be useful to you.
Once you've got the parameters saved you can load them with the load command.
To sum up: create a variable (most likely a struct or cell array) called parameters and save it in the data directory for the experiment it refers to. You then have all the usual Matlab tools for reading, writing and investigating the parameters as well as the data. I don't see a need for a solution more complicated than this (though your parameters may be complicated themselves).
What is a good strategy for dealing with changing product and feature names in source code. Here's the situation I find myself in over and over again (most of you can relate?)...
Product name starts off as "DaBomb"
Major features are "Exploder", "Lantern" and "Flag".
Time passes, and the Feature names are changed to "Boom", "Lighthouse" and "MarkMan"
Time passes, and the product name changes to "DaChronic"
...
...
Blah, blah, blah...over and over and over
And now we have a large code base with 50 different names sprinkled around the directory tree and source files, most of which are obsolete. Only the veterans remember what each name means, the full etimologic history, etc.
What is the solution to this mess?
Clarification: I don't mean the names that customers see, I mean the names of directories, source files, classes, variables, etc. that the developers see where the changing product and feature names get woven into.
Given your clarification that you "don't mean the names that customers see, [you] mean the names of directories, source files, classes, variables, etc. that the developers see", yeah, this can be an annoying problem.
The way teams I've been on have coped with best when we've had a policy of always using only one name for each thing in the code base. If the name changes later on we either stay with the old name in the code, or we migrate all instances of the old name to the new name. The important thing is to never start using the new name in the code unless all instance of the old name have been migrated. That way you only ever have to keep 2 names for something in your head: the "old name", used in the code, and the name everyone else uses.
We've also often chosen a very generic/descriptive name for things when starting out if we know the "brand name" is likely to change.
I consider renaming to better naming conventions just another form of refactoring. Create a branch, perform the renames, run unit/integration tests, commit, merge, repeat. It's all about process control to keep consistency in the project.
The solution to the mess is to not create it in the first place. Once a code path is named, there's rarely a good reason to change it and never a good reason to use a new name alongside the old one. When "Exploder" becomes "Boom", you have two choices: Either keep using Exploder exclusively, and never mention Boom anywhere, or change all instances of Exploder to Boom and then continue on using Boom exclusively and never mention Exploder again.
If you're using both Exploder and Boom in the same code base, you're doing it wrong.
Also, I know you clarified that you're not talking about the user-visible names, but, if you start out working with your own internal names which are relevant to what the code does and completely independent of what marketing wants to call the product/feature, then this is much less likely to become an issue. If you're already referring to Exploder internally as TNT, then what difference does it make if Exploder gets changed to Boom?
How do you deal with Localization? Same thing; same method.
We use an internal and and external name. It could be as simple as a static variable definition like
public static final String EXPLODER = "Boom";
And in code you'll always use the reference to EXPLODER. Same for path names and the like - hard coding those paths at different places is a no-go anyway. If some guys starts digging through internal stuff (like JS sources or ini files or whatever), who cares if they discover Exploder?
Just use internal names, and ignore changes to marketing/official names: https://softwareengineering.stackexchange.com/a/208578/55472.