Impossible to make href links work properly

[Hellisotherpeople]

I'm trying to make a web-page that displays a bunch of values from MongoDB, here is my code:

class LangCol(Col):             # This lets me get a webaddress into the table
    def td_format(self, content):
        parsed=urllib.parse.unquote(content)
        split = urlsplit(parsed)

        return ('<a href='+("".join(['http://',split.netloc, split.path]))+ '>'+content+'</a>')



class ItemTable(Table):
    ID = Col('IDs')
    type = Col("type")
    Job_URL = LangCol("URL")

items = mongodb.bdb.find({"OS" : "CentOS7.3"})
items2 = mongodb.bdb.find({"OS" : "RHEL7.3"})
# Get some objects
#class Item(object):
#    def __init__(self, name, description):
#        self.name = name
#        self.description = description
#items = [Item('Job1', 'Job1'),
#         Item('Job2', 'Job2'),
#         Item('Job3', 'Job3')]


app = Flask(__name__)

@app.route('/')
def index():
    table = ItemTable(items)
    table2 = ItemTable(items2)
    return table.__html__()

The relevant code is the return statement of LangCol
I've tried other returns, such as (the one I REALLY hoped would worked)

return ('<a href='+content+ '>'+content+'</a>')

Unfortunately, no matter what I do, I either get a URL that includes my hosted flask server
(like http://127.0.0.1:5000/http%3A//10.23.182.101%3A8080/job/%28CHPC%29%20Factory%20-%20CentOS%207.3%20x86_TS/57/)
or, if I unquote my weburl instead, it will truncate everything after part of my link
(like http://10.23.182.101:8080/job/(CHPC) )

This issue is very frustrating, because the closest thing to a solution I've found looks like it should, but doesn't work correctly.

https://stackoverflow.com/questions/17056408/flask-jinja2-href-not-linking-correctly

As we can see, content displays the exact URL correctly on the page. I want this exact URL to be a clickable hyperlink to the address that it prints. Unfortunately, this seems to be impossible.

I'm an intern at a large tech company which probably makes your CPU, and I (along with my team) am very inexperienced with web technologies. Apologies if I'm doing something silly and don't notice it.

[plumdog]

Hi! I'm glad you're using flask table, and thanks for asking a question!

I suspect part of the problem here is that you haven't got quotes around the value for your href. Eg:

<a href="http://myurl.com/test thing">My link<a>

is different HTML to

<a href=http://myurl.com/test thing>My link<a>

as GitHub's HTML syntax highlighting nicely shows.

You get away with this if your URL doesn't have any spaces or things like < or > in, but using quotes is definitely best practice here regardless, and you definitely need them because your links have spaces in.

So I suspect that

return '<a href="' + content + '">' + content + '</a>'

will probably do it. However, you will still run into problems if your URLs ever have " in. So you can make use of the html helper in flask_table.

# with your imports:
from flask_table.html import element
...

# then in your td_format, just do:
return element('a', attrs=dict(href=content), content=content)
# to get an anchor with the given URL as the href and the displayed text

---

Also, the problem that you had where the flask application's URL at the start will be happen if you set the href to something that doesn't look like a full URL. Then your browser says "this isn't a proper URL, it must be relative to the current page".

This points towards a generally pretty good debugging strategy for stuff like this where it pays to check exactly what HTML you're actually producing - sometimes browsers fudge and patch up bits of HTML to try to make it work. Writing something that prints the HTML to your console, or - better still maybe - write a unit test is a great way of making sure your code is actually doing what you want it to.

[plumdog]

Hi @Rainsilves, I'm closing this issue as it's been a while without activity. But if you still have questions about the above, the please do reopen and ask.

[Hellisotherpeople]

I am sorry Plumdog, I ended up moving in a somewhat different direction with the project and will not use flask_table. I am very thankful for your long post explaining a solution!

[CheapB]

I am trying to do the same except I need the displayed value to be another fieldname from db.model - similar to using attr in LinkCol
`

class UrlCol(Col):
def td_format(self, content,attr):
return element('a', attrs=dict(href=content), content=attr)

class ProductStoreTable(Table):
store = LinkCol('Store', 'productstoreupsert', url_kwargs=dict(productid='productid',storeid='storeid'),attr='store')

Product = UrlCol('Product', 'url',attr='product')
`

I am getting "TypeError: init() got multiple values for argument 'attr'" What am I missing?

[plumdog]

@CheapB Hi!

What you're getting there is just a plain old Python error. Your UrlCol inherits from Col without overriding __init__, so it looks like:

def __init__(self, name, attr=None, ...

Your UrlCol('Product', 'url',attr='product') calls this __init__ with attr set twice.

Which of 'url' and 'product' do you want to be the attr? And what do you want the other one to be?

[CheapB]

Thanks for the fast response. What I am trying to do is '<a href="' + url+ '">' + product+ '</a>'
where both url and product are columns in my db.model.

[plumdog]

You perhaps want to use LinkCol for both of store = ... and Product = ...?

[CheapB]

You perhaps want to use LinkCol for both of store = ... and Product = ...?

It i understand it correctly LinkCol is only for urls native to the app and calls a function. I am looking to have an internet url (content of url) such as "https://www.totalwine.com/spirits/gin/monkey-47-schwarzwald-dry-gin/p/139532375?s=1501&igrules=true"

[plumdog]

@CheapB You are absolutely right.

I've added an example here: #116 that I think does what you want.

That example gives output that looks like

<table>
  <thead><tr><th>URL</th></tr></thead>
  <tbody>
    <tr><td><a href="https://google.com">Google</a></td></tr>
    <tr><td><a href="https://yahoo.com">Yahoo</a></td></tr>
  </tbody>
</table>

which becomes:

URL
Google
Yahoo

It might be worth flask_table growing a dedicated column class that does something like this.

[CheapB]

That is EXACTLY what I was going for. I am working on getting all my templates moved to Flask Table and this is a huge step in the right direction. Thank you very much.