Get group from D3js selectAll in console? - d3.js

In the context of understanding better the details of D3.js, I am a bit puzzled how selectAll works.
For example, based on this codepen, it is possible to write:
vis.selectAll("circle.nodes")
or:
vis.selectAll("my_own_tag_group")
But after the D3js code is executed, I would expect that the selectAll gives a group that I could access from the web console too:
document.getElementsByClassName('my_own_tag_group')
HTMLCollection [ ] (empty)
What am I missing from the explanations given in http://bost.ocks.org/mike/selection/

At least from your code, it looks like you're doing the selection wrong. selectAll follows CSS3 selector rules:
D3 uses CSS3 to select elements. For example, you can select by tag ("div"), class (".awesome"), unique identifier ("#foo"), attribute ("[color=red]"), or containment ("parent child"). Selectors can also be intersected (".this.that" for logical AND) or unioned (".this, .that" for logical OR). If your browser doesn't support selectors natively, you can include Sizzle before D3 for backwards-compatibility.
Therefore, you'd probably want to use
vis.selectAll(".my_own_tag_group")
if it refers to a class, and
vis.selectAll("#my_own_tag_group")
if it refers to an id (which might either make sense or not).
If it refers to something else, you might want to restructure it so that it refers to a class.

Related

XPath fails because Namespace colon in Title

I'm generating an XML report, using the JDF standard for PDFs going into a printing workflow.
There are 3 "DPart" sections, and I can use an xPath query to recognize them, but I want to grab the "Separation" attribute of each "cip4:Part". I can also get a query to find that, but it does not distinguish between the multiple "DPart"s.
<DPart End="0" ID="0003" ParentRef="0002" Start="0">
<DPM>
<cip4:Root>
<cip4:Intent cip4:ProductType="ProductPart"/>
<cip4:Production>
<cip4:Resource>
<cip4:Part Separation="K1"/>
<cip4:Color cip4:ActualColorName="Black" cip4:ColorType="Normal">
</cip4:Resource>
<cip4:Resource>
<cip4:Part Separation="S1"/>**
<cip4:Color cip4:ActualColorName="Dieline" cip4:ColorType="Normal">
</cip4:Resource>
<cip4:Resource>
<cip4:ColorantControl ColorantOrder="K1 S1" ColorantParams="K1 S1"/>
</cip4:Resource>
<cip4:Resource>
<eg:InkCoverage>
<eg:InkCov eg:Mm2="0.000000" eg:Pct="0.000000" eg:Separation="K1"/>
<eg:InkCov eg:Mm2="182.337538" eg:Pct="0.721209" eg:Separation="S1"/>
</eg:InkCoverage>
</cip4:Resource>
</cip4:Production>
</cip4:Root>
</DPM>
</DPart>
I want to do something like:
/DPM[2]/*[name ()='cip4:Part'], but it's not working.
I'm in a low-code pre-press environment (Esko Automation Engine), but the system gives me tools to parse an xPath, and throw some JavaScript at it.
There are at least three reasons your XPath selects nothing:
DPM is not an immediate child of the root node
There is only one DPM, so DPM[2] won't select anything
There is no child of a DPM whose name is cip4:Part.
You also say in the narrative that there are three DPart's, which implies that DPart is not actually the outermost element as it appears to be in your sample. This makes it difficult to provide the correct XPath. However, you might be able to make a start with
(//DPM)[2]//*[name()='cip4:Part']

Using selectAll in d3.js

I would like to selectAll X that have the properties Y and Z. For instance, I would specifically like to select all lines with an ID of d.id AND a target of d.target. It's the 'and' part that I can't figure out; I assumed from the documentation that it should be something like this:
selectedLine = d3.selectAll("line[id="+d.id+"]").selectAll(line[target="+d.target+"]");
But calling selectAll on a selection always returns an empty selection to me, regardless of the contents (In this case, I'm certain that exists one line with an ID of d.id and a target of d.target).
I suspect that target is not an attribute that the line element but a data property instead. Besides that, calling selectAll on a selection does not return an empty selection: you probably have some other problem. Finally, pay attention to the fact that you are using selectAll with an ID, which makes little sense: IDs have to be unique.
Anyway, whatever you are using in those attribute selectors, you can simply use multiple attribute selectors:
selectedLine = d3.selectAll("line[id='foo'][target='bar']")
According to the documentation:
Multiple attribute selectors can be used to refer to several attributes of an element, or even several times to the same attribute.
Here, the selector matches all SPAN elements whose "hello" attribute has exactly the value "Cleveland" and whose "goodbye" attribute has exactly the value "Columbus":
span[hello="Cleveland"][goodbye="Columbus"]

getting attribute via xpath query succesfull in browser, but not in Robot Framework

I have a certain XPATH-query which I use to get the height from a certain HTML-element which returns me perfectly the desired value when I execute it in Chrome via the XPath Helper-plugin.
//*/div[#class="BarChart"]/*[name()="svg"]/*[name()="svg"]/*[name()="g"]/*[name()="rect" and #class="bar bar1"]/#height
However, when I use the same query via the Get Element Attribute-keyword in the Robot Framework
Get Element Attribute//*/div[#class="BarChart"]/*[name()="svg"]/*[name()="svg"]/*[name()="g"]/*[name()="rect" and #class="bar bar1"]/#height
... then I got an InvalidSelectorException about this XPATH.
InvalidSelectorException: Message: u'invalid selector: Unable to locate an
element with the xpath expression `//*/div[#class="BarChart"]/*[name()="svg"]/*
[name()="svg"]/*[name()="g"]/*[name()="rect" and #class="bar bar1"]/`
So, the Robot Framework or Selenium removed the #-sign and everything after it. I thought it was an escape -problem and added and removed some slashes before the #height, but unsuccessful. I also tried to encapsulate the result of this query in the string()-command but this was also unsuccessful.
Does somebody has an idea to prevent my XPATH-query from getting broken?
It looks like you can't include the attribute axis in the XPath itself when you're using Robot. You need to retrieve the element by XPath, and then specify the attribute name outside that. It seems like the syntax is something like this:
Get Element Attribute xpath=(//*/div[#class="BarChart"]/*[name()="svg"]/*[name()="svg"]/*[name()="g"]/*[name()="rect" and #class="bar bar1"])#height
or perhaps (I've never used Robot):
Get Element Attribute xpath=(//*/div[#class="BarChart"]/*[name()="svg"]/*[name()="svg"]/*[name()="g"]/*[name()="rect" and #class="bar bar1"])[1]#height
This documentation says
attribute_locator consists of element locator followed by an # sign and attribute name, for example "element_id#class".
so I think what I've posted above is on the right track.
You are correct in your observation that the keyword seems to removes everything after the final #. More correctly, it uses the # to separate the element locator from the attribute name, and does this by splitting the string at that final # character.
No amount of escaping will solve the problem as the code isn't doing any parsing at this point. This is the exact code (as of this writing...) that performs that operation:
def _parse_attribute_locator(self, attribute_locator):
parts = attribute_locator.rpartition('#')
...
The simple solution is to drop that trailing slash, so your xpath will look like this:
//*/div[#class="BarChart"]/... and #class="bar bar1"]#height`

Retrieve an xpath text contains using text()

I've been hacking away at this one for hours and I just can't figure it out. Using XPath to find text values is tricky and this problem has too many moving parts.
I have a webpage with a large table and a section in this table contains a list of users (assignees) that are assigned to a particular unit. There is nearly always multiple users assigned to a unit and I need to make sure a particular user is assigned to any of the units on the table. I've used XPath for nearly all of my selectors and I'm half way there on this one. I just can't seem to figure out how to use contains with text() in this context.
Here's what I have so far:
//td[#id='unit']/span [text()='asdfasdfasdfasdfasdf (Primary); asdfasdfasdfasdfasdf, asdfasdfasdfasdf; 456, 3456'; testuser]
The XPath Query above captures all text in the particular section I am looking at, which is great. However, I only need to know if testuser is in that section.
text() gets you a set of text nodes. I tend to use it more in a context of //span//text() or something.
If you are trying to check if the text inside an element contains something you should use contains on the element rather than the result of text() like this:
span[contains(., 'testuser')]
XPath is pretty good with context. If you know exactly what text a node should have you can do:
span[.='full text in this span']
But if you want to do something like regular expressions (using exslt for example) you'll need to use the string() function:
span[regexp:test(string(.), 'testuser')]

Query html tag with XPath

I am writing the selenium test.
I have a label there "Assign Designer" and the select box followed right after the label.
Unfortunetely, select box has the dynamic id and I can not query it by id or any other it's attribute.
Can I build the XPath query that returns "First select tag after text 'Assign Designer'"?
PS. Selenium supports only XPath 1.0
This would be something like:
//label[text() = 'Assign Designer']/following-sibling::select[1]
Note that:
The // shorthand is quite inefficient, because it causes a document-wide scan. If you can be more specific about the label's position, I recommend doing so. If the document is small, however, this won't be a problem.
Since I don't know much about Selenium, I used "label". If it is not a <label>, you should use the actual element name, of course. ;-)
be sure to include a position predicate ([1], in this case) whenever you use an axis like "following-sibling". It's easily forgotten and if it is, your expressions may produce unexpected results.

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