How to insert a string after a specific closing curly brace in Python?

Question

I'm trying to insert a sub string right after a specific closing curly brace of a string.

For example let's say the full string looks like following:

"{records#QUERY# { edges { node { id legalname countryiso naicscode naicsdescription } } <need to place another string here> } }"

So I'd need to like append a string in that place holder <> above (please note that in the original string this place holder won't be provided).

Basically I need to find out the closing curly brace of the second opening curly brace and place it before that.

Any help or pointers could be appreciated.

maybe look at this question, it is fairly similar: https://stackoverflow.com/questions/1883980/find-the-nth-occurrence-of-substring-in-a-string - here it would get you the position of the character and then use this to insert the string https://www.adamsmith.haus/python/answers/how-to-insert-a-character-into-a-string-at-an-index-in-python — Oliver, Oct 06 '22 at 06:17
Double curly brackets? `"{{records#QUERY# {{ edges {{ xx }} }} {} }}".format('xxx')`? — r.user.05apr, Oct 06 '22 at 06:19
thnx @r.user.05apr Unfortunately we can't change that query.. since its coming from a metadata service..plus it doesn't come with a place holder in the original string. I need to find and append it — Kulasangar, Oct 06 '22 at 06:25

score 1 · Answer 1 · answered Oct 06 '22 at 06:29

1

Hi| Is the end always the same ? "}} }}" if so you can remove it and add it witht he new text.

text = "{records#QUERY# { edges { node { id legalname countryiso naicscode naicsdescription } } } }"
text_split = ss.strip("} }")

new_text2 = text_split+("} } New Text Inserted } }")

answered Oct 06 '22 at 06:29

Dini

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1
12

thnx @dini.. yeah the end will be always the same.. but i have one question in the above approach.. how will it know to strip the last two curly braces and not the ones before that? – Kulasangar Oct 06 '22 at 06:37
It will remove the last 4 because we said }} and they appear twice and then we add {{ text }} – Dini Oct 07 '22 at 09:15

score 1 · Answer 2 · answered Oct 06 '22 at 07:36

Dini's answer is practical, but if you want to use regex for this purpose, one solution may be:

import re
string = "{records#QUERY# { edges { node { id legalname countryiso naicscode naicsdescription } } <need to place another string here> } }"
match = re.search("\{.*?\{.*?\{.*?\{.*?\}.*?(\}).*?(\}).*?\}",string)

idx1 = match.span(1)[0] # index of second "}"
idx2 = match.span(2)[0] # index of third "}"

string = string[:idx1+1] + " " + "apple" + " " + string[idx2:]
print(string)

Output is:

{records#QUERY# { edges { node { id legalname countryiso naicscode naicsdescription } } apple } }

Regex will be a better solution, yes. – Dini Oct 07 '22 at 09:24 — Dini, Oct 07 '22 at 09:24

Kulasangar · Answer 3 · 2022-10-06T10:33:42.317

I managed to resolve this by finding the indices of the second close curly brace from last and the third and placed the string in between them:

fetcher_query = "{records#QUERY# { edges { node { id legalname countryiso naicscode naicsdescription}}}}"
    
close_curly_brace_iterator = re.finditer(r"}", fetcher_query)
indices = [m.start(0) for m in close_curly_brace_iterator]

third_before_last_idx = indices[-2]  # index of third from last }
second_before_last_idx = indices[-3]  # index of second from last }

fetcher_query = fetcher_query[:third_before_last_idx] + " " + "pageInfo {endCursor hasNextPage}" + " " + fetcher_query[second_before_last_idx:-1]
logger.info(f'updated fetcher query with graphql pagination: {fetcher_query}')

How to insert a string after a specific closing curly brace in Python?

3 Answers3