Mechanize users - Nov 2006 - Adding fields to a form

Is there a decent way to add a field to a form before posting it?  I  
haven''t tried using HPricot manipulations just yet, since I
can''t
ever find really solid docs on hpricot....

Form#[]= doesn''t work because it first searches only pre-existing  
fields.  I''m investigating how to write  a patch now.

But I thought maybe someone here might have an idea.

Thanks in advance,
Mat

On Nov 2, 2006, at 3:32 PM, Mat Schaffer wrote:
> Is there a decent way to add a field to a form before posting it?   
> I haven''t tried using HPricot manipulations just yet, since I
can''t
> ever find really solid docs on hpricot....
>
> Form#[]= doesn''t work because it first searches only pre-existing
> fields.  I''m investigating how to write  a patch now.
>
> But I thought maybe someone here might have an idea.
>
> Thanks in advance,
> Mat
Well I think I answered my own question.  Aaron, you deserve some  
props.  I haven''t found a quirk in Mechanize yet that I
couldn''t
patch in one line of code.  Way to be extensible.

--- field_patch.rb ---

class WWW::Mechanize::Form
   # Fetch the first field whose name is equal to field_name, or  
create a new field
   def field(field_name)
     fields.find { |f| f.name.eql? field_name } || fields <<  
WWW::Mechanize::Field.new(field_name, '''')
   end
end

--- end field_patch.rb ---

On Thu, Nov 02, 2006 at 03:41:18PM -0500, Mat Schaffer
wrote:
> On Nov 2, 2006, at 3:32 PM, Mat Schaffer wrote:
> > Is there a decent way to add a field to a form before posting it?   
> > I haven''t tried using HPricot manipulations just yet, since I
can''t
> > ever find really solid docs on hpricot....
> >
> > Form#[]= doesn''t work because it first searches only
pre-existing
> > fields.  I''m investigating how to write  a patch now.
> >
> > But I thought maybe someone here might have an idea.
> >
> > Thanks in advance,
> > Mat
> 
> Well I think I answered my own question.  Aaron, you deserve some  
> props.  I haven''t found a quirk in Mechanize yet that I
couldn''t
> patch in one line of code.  Way to be extensible.
Thanks!  I''ll apply this patch and it will be in the next release.

--Aaron

-- 
Aaron Patterson
http://tenderlovemaking.com/

Hey Mat,

On Thu, Nov 02, 2006 at 03:41:18PM -0500, Mat Schaffer
wrote:
> On Nov 2, 2006, at 3:32 PM, Mat Schaffer wrote:
> > Is there a decent way to add a field to a form before posting it?   
> > I haven''t tried using HPricot manipulations just yet, since I
can''t
> > ever find really solid docs on hpricot....
> >
> > Form#[]= doesn''t work because it first searches only
pre-existing
> > fields.  I''m investigating how to write  a patch now.
> >
> > But I thought maybe someone here might have an idea.
> >
> > Thanks in advance,
> > Mat
> 
> Well I think I answered my own question.  Aaron, you deserve some  
> props.  I haven''t found a quirk in Mechanize yet that I
couldn''t
> patch in one line of code.  Way to be extensible.
> 
> --- field_patch.rb ---
> 
> class WWW::Mechanize::Form
>    # Fetch the first field whose name is equal to field_name, or  
> create a new field
>    def field(field_name)
>      fields.find { |f| f.name.eql? field_name } || fields <<  
> WWW::Mechanize::Field.new(field_name, '''')
>    end
> end
> 
> --- end field_patch.rb ---
I was thinking about this patch for a little bit, and I think it might
be a little dangerous to add a field without the user explicitly
knowing.

I don''t see the Form#field method as a destructive method.  Would you
be
okay with having an "add_field!" method, and also having the
Form#[]method be destructive?  That would make the Form class more Hash like.

Basically these two code snippets would be exactly the same:

  form.add_field!(''name'', ''Aaron'')  #The
second arg could be nil

-or-

  form[''name''] = ''Aaron''

Both of those would create a new field.  Let me know what you think.

--Aaron

-- 
Aaron Patterson
http://tenderlovemaking.com/

Aaron Patterson wrote:
> I was thinking about this patch for a little bit, and I think it might
> be a little dangerous to add a field without the user explicitly
> knowing.
I agree 100%. Had a partially composed email saying the same thing.

Your recommendations are good.

Jon

On Nov 3, 2006, at 1:22 PM, Aaron Patterson wrote:
> I was thinking about this patch for a little bit, and I think it might
> be a little dangerous to add a field without the user explicitly
> knowing.
>
> I don''t see the Form#field method as a destructive method.  Would
> you be
> okay with having an "add_field!" method, and also having the
Form#[]> method be destructive?  That would make the Form class more Hash
like.
>
> Basically these two code snippets would be exactly the same:
>
>   form.add_field!(''name'', ''Aaron'') 
#The second arg could be nil
>
> -or-
>
>   form[''name''] = ''Aaron''
>
> Both of those would create a new field.  Let me know what you think.
>
> --Aaron
Yeah, that''s a really good point.  I only needed statements like form 
[''name''] = ''Aaron'' work, and adding to the
Form#field method seemed
to be the simplest way to achieve that.

Since the form is accessed like a Hash, using Form#[]= makes sense to  
me.  Probably the most intuitive and it doesn''t add another method to  
the interface.  add_field! isn''t bad either though, if that''s
your
fancy.

Good catch, thanks,
Mat