I'm trying to get this Sinatra GET request to work:
get '/:year/:month/:day/:slug' do
end
I know you can get one param to work with block parameters:
get '/:param' do |param|
"Here it is: #{param}."
end
But how can I use multiple block parameters with the first code block? I'm open to other methods.
Multiple placeholders are stored in params as Hash.
# Request to /2009/10/20/post.html
get '/:year/:month/:day/:slug' do
params[:year] # => 2009
params[:month] # => 10
params[:day] # => 20
params[:post] # => post.html
end
Forgive my ignorance of Sinatra, but shouldn't this set named parameters like Rails map.connect?:
get '/:year/:month/:day/:slug
Now the parameters should be accessible in the params hash:
params = { :year => "foo", :month => "bar", :day => "baz", :slug => "etc" }
Related
Is there the possibility in Ruby to use a variable / string to define a file path?
For example I would like to use the variable location as follow:
location = 'C:\Users\Private\Documents'
#### some code here ####
class Array
def to_csv(csv_filename)
require 'csv'
CSV.open(csv_filename, "wb") do |csv|
csv << first.keys # adds the attributes name on the first line
self.each do |hash|
csv << hash.values
end
end
end
end
array = [{:color => "orange", :quantity => 3},
{:color => "green", :quantity => 1}]
array.to_csv('location\FileName.csv')
You can use variable inside string, following way:
array.to_csv("#{location}\FileName.csv")
You can use File.join, which accepts variables as arguments.
irb(main):001:0> filename = File.basename('/home/gumby/work/ruby.rb')
=> "ruby.rb"
irb(main):002:0> path = '/home/gumby/work'
=> "/home/gumby/work"
irb(main):003:0> File.join(path, filename)
=> "/home/gumby/work/ruby.rb"
As noted above, if you start embedding slashes in your strings things may get unmanageable in future.
I want to define a method_missing function for one of my classes, and I want to be able to pass in a hash as the argument list instead of an array. Like this:
MyClass::get_by_id {:id => id}
MyClass::get_by_id {:id => id, :filters => filters}
MyClass::get_by_id {:id => id, :filters => filters, :sort => sort}
As far as I can tell, the args list gets passed in as an array, so keys get dropped and there's no way to tell which arguments is which. Is there a way to force Ruby to treat the argument list in method_missing as a hash?
What issue are you having? This works for me:
class MyClass
def self.method_missing name, args
puts args.class
puts args.inspect
end
end
MyClass.foobar :id => 5, :filter => "bar"
# Hash
# {:id=>5, :filter=>"bar"}
Is this what you are looking for ?
class Foo
def self.method_missing(name,*args)
p args
p name
end
end
Foo.bar(1,2,3)
# >> [1, 2, 3]
# >> :bar
I'm answering my own question based on experimentation that I've done since asking. When using a hash splat on the arg list, you can pass in a hash like this:
MyClass::get_by_id(:id => id, :filters => filters)
And the argument list will look like this:
[
{
:id => id,
:filters => filters
}
]
Ruby places the key/value pairs into a single hash object at location args[0]. If you call the method like this:
MyClass::get_by_id(id, :filters => filters)
Your argument list will be this:
[
id,
{:filters => filters}
]
So basically, key/value pairs are merged together into a single hash and passed in order.
I would like to return the results of a SOQL query as JSON, but the data seems to be returned as a string.
client = SFDC_Adapter.login
data = client.query("SELECT MarkupAmount__c,
MarkupPercent__c,
Product_Type_Id__c,
Product_Type__c
FROM Product_Type__c
WHERE Product_Type_Id__c = #{product_type_id}")
p data
=> [#<Product_Type__c:0x00000001c356f8 #Id=nil, #OwnerId=nil, #IsDeleted=nil, #Name=nil, #CreatedDate=nil, #CreatedById=nil, #LastModifiedDate=nil, #LastModifiedById=nil, #SystemModstamp=nil, #MarkupPercent__c=5.0, #Subscription__c=nil, #Product_Type__c="Research Trip", #MarkupAmount__c=nil, #Product_Type_Id__c=36.0>]
puts data
=> #<Product_Type__c:0x00000001c356f8>
puts data.to_json
=> ["#<Product_Type__c:0x00000001c356f8>"]
How do I materialize these results into a JSON object for use in a Restful service?
I don't know that gem, but from looking at your output, and glancing at your results, it looks like you got a Product_Type object back.
When you use p or puts, inspect is being used, which is turning the instance into something viewable in a web-page, by using an HTML encoding on it. That's why you see < and > in the output.
Instead, you need to access the values in the object. According to the docs, you can use standard getters or using a hash[key] form to do that:
contact = Contact.find("contact_id") #=> #
contact = Contact.find_by_Name("John Smith") #=> dynamic finders!
contacts = Contact.all #=> a Databasedotcom::Collection of Contact instances
contacts = Contact.find_all_by_Company("IBM") #=> a Databasedotcom::Collection of matching Contacts
contact.Name #=> the contact's Name attribute
contact["Name"] #=> same thing
contact.Name = "new name" #=> change the contact's Name attribute, in memory
contact["Name"] = "new name" #=> same thing
contact.save #=> save the changes to the database
contact.update_attributes "Name" => "newer name",
"Phone" => "4156543210" #=> change several attributes at once and save them
contact.delete #=> delete the contact from the database
Try data['Product_Type_Id'] and you should get 36.0. An alternate way of doing the same thing is data.Product_Type_Id.
Once you have your accessors figured out you can generate JSON using a simple hash or array of hashes. This would generate a hash:
require 'json'
hash = {
'Id' => data.Id,
'OwnerId' => data.OwnerId,
'IsDeleted' => data.IsDeleted,
'Name' => data.Name,
'CreatedDate' => data.CreatedDate,
'CreatedById' => data.CreatedById,
'LastModifiedDate' => data.LastModifiedDate,
'LastModifiedById' => data.LastModifiedById,
'SystemModstamp' => data.SystemModstamp,
'MarkupPercent' => data.MarkupPercent,
'Subscription' => data.Subscription,
'Product_Type' => data.Product_Type,
'MarkupAmount' => data.MarkupAmount,
'Product_Type_Id' => data.Product_Type_Id,
}
puts hash.to_json
I didn't see a to_h or to_hash method which would be a shortcut.
My form receives data via POST. When I do puts params I can see:
{"id" => "123", "id2" => "456"}
now the commands:
puts params['id'] # => 123
puts params[:id] # => 123
params['id'] = '999'
puts params # => {"id" => "999", "id2" => "456"}
but when I do:
params[:id] = '888'
puts params
I get
{"id" => "999", "id2" => "456", :id => "888"}
In IRB it works fine:
params
# => {"id2"=>"2", "id"=>"1"}
params[:id]
# => nil
params['id']
# => "1"
Why can I read the value using :id, but not set the value using that?
Hashes in Ruby allow arbitrary objects to be used as keys. As strings (e.g. "id") and symbols (e.g. :id) are separate types of objects, a hash may have as a key both a string and symbol with the same visual contents without conflict:
irb(main):001:0> { :a=>1, "a"=>2 }
#=> {:a=>1, "a"=>2}
This is distinctly different from JavaScript, where the keys for objects are always strings.
Because web parameters (whether via GET or POST) are always strings, Sinatra has a 'convenience' that allows you to ask for a parameter using a symbol and it will convert it to a string before looking for the associated value. It does this by using a custom default_proc that calls to_s when looking for a value that does not exist.
Here's the current implementation:
def indifferent_hash
Hash.new {|hash,key| hash[key.to_s] if Symbol === key }
end
However, it does not provide a custom implementation for the []=(key, val) method, and thus you can set a symbol instead of the string.
Given the following code,
How would you refactor this so that the method search_word has access to issueid?
I would say that changing the function search_word so it accepts 3 arguments or making issueid an instance variable (#issueid) could be considered as an example of bad practices, but honestly I cannot find any other solution. If there's no solution aside from this, would you mind explaining the reason why there's no other solution?
Please bear in mind that it is a Ruby on Rails model.
def search_type_of_relation_in_text(issueid, type_of_causality)
relation_ocurrences = Array.new
keywords_list = {
:C => ['cause', 'causes'],
:I => ['prevent', 'inhibitors'],
:P => ['type','supersets'],
:E => ['effect', 'effects'],
:R => ['reduce', 'inhibited'],
:S => ['example', 'subsets']
}[type_of_causality.to_sym]
for keyword in keywords_list
relation_ocurrences + search_word(keyword, relation_type)
end
return relation_ocurrences
end
def search_word(keyword, relation_type)
relation_ocurrences = Array.new
#buffer.search('//p[text()*= "'+keyword+'"]/a').each { |relation|
relation_suggestion_url = 'http://en.wikipedia.org'+relation.attributes['href']
relation_suggestion_title = URI.unescape(relation.attributes['href'].gsub("_" , " ").gsub(/[\w\W]*\/wiki\//, ""))
if not #current_suggested[relation_type].include?(relation_suggestion_url)
if #accepted[relation_type].include?(relation_suggestion_url)
relation_ocurrences << {:title => relation_suggestion_title, :wiki_url => relation_suggestion_url, :causality => type_of_causality, :status => "A", :issue_id => issueid}
else
relation_ocurrences << {:title => relation_suggestion_title, :wiki_url => relation_suggestion_url, :causality => type_of_causality, :status => "N", :issue_id => issueid}
end
end
}
end
If you need additional context, pass it through as an additional argument. That's how it's supposed to work.
Setting #-type instance variables to pass context is bad form as you've identified.
There's a number of Ruby conventions you seem to be unaware of:
Instead of Array.new just use [ ], and instead of Hash.new use { }.
Use a case statement or a constant instead of defining a Hash and then retrieving only one of the elements, discarding the remainder.
Avoid using return unless strictly necessary, as the last operation is always returned by default.
Use array.each do |item| instead of for item in array
Use do ... end instead of { ... } for multi-line blocks, where the curly brace version is generally reserved for one-liners. Avoids confusion with hash declarations.
Try and avoid duplicating large chunks of code when the differences are minor. For instance, declare a temporary variable, conditionally manipulate it, then store it instead of defining multiple independent variables.
With that in mind, here's a reworking of it:
KEYWORDS = {
:C => ['cause', 'causes'],
:I => ['prevent', 'inhibitors'],
:P => ['type','supersets'],
:E => ['effect', 'effects'],
:R => ['reduce', 'inhibited'],
:S => ['example', 'subsets']
}
def search_type_of_relation_in_text(issue_id, type_of_causality)
KEYWORDS[type_of_causality.to_sym].collect do |keyword|
search_word(keyword, relation_type, issue_id)
end
end
def search_word(keyword, relation_type, issue_id)
relation_occurrences = [ ]
#buffer.search(%Q{//p[text()*= "#{keyword}'"]/a}).each do |relation|
relation_suggestion_url = "http://en.wikipedia.org#{relation.attributes['href']}"
relation_suggestion_title = URI.unescape(relation.attributes['href'].gsub("_" , " ").gsub(/[\w\W]*\/wiki\//, ""))
if (!#current_suggested[relation_type].include?(relation_suggestion_url))
occurrence = {
:title => relation_suggestion_title,
:wiki_url => relation_suggestion_url,
:causality => type_of_causality,
:issue_id => issue_id
}
occurrence[:status] =
if (#accepted[relation_type].include?(relation_suggestion_url))
'A'
else
'N'
end
relation_ocurrences << occurrence
end
end
relation_occurrences
end