How to split a long Go template function across multiple lines?

Question

I have a very long printf call in a Go template. Example:

{{ printf "mongodb://%s:%s@%s/%s?authSource=admin&replicaSet=%s&readPreference=nearest&w=majority" .Values.rocketchat.mongo.username .Values.rocketchat.mongo.password .Values.rocketchat.mongo.database .Values.mongodb-replicaset.replicaSetName | b64enc | quote }}

How can I split this across multiple lines (like below)?

{{ printf "mongodb://%s:%s@%s/%s?authSource=admin&replicaSet=%s&readPreference=nearest&w=majority"
    .Values.rocketchat.mongo.username
    .Values.rocketchat.mongo.password
    .Values.rocketchat.mongo.database
    .Values.mongodb-replicaset.replicaSetName
    | b64enc | quote }}

The only way to do that would be to change your function to take a composite type (such as a `struct` or `map`), then build that composite type line-by-line. But don't do that. Generally speaking, but doubly so in templates, if you feel your lines are too long, it means you need to refactor with a simplification. — Jonathan Hall, Apr 13 '18 at 12:42

score 19 · Accepted Answer · answered Apr 13 '18 at 12:27

19

This cannot be done. From the text/template documentation:

Except for raw strings, actions may not span newlines, although comments can.

answered Apr 13 '18 at 12:27

score 1 · Answer 2 · answered Feb 18 '23 at 19:51

1

For posterity, since Go 1.16 you can have template actions span more than one line; from the release notes:

Newlines characters are now allowed inside action delimiters, permitting actions to span multiple lines.

(example implementation)

answered Feb 18 '23 at 19:51

Carrotman42

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score 0 · Answer 3 · answered Jul 05 '20 at 16:26

0

I think you need to use string literals instead, see some examples here: https://golang.org/src/html/template/example_test.go

answered Jul 05 '20 at 16:26

Ariel Monaco

3,695
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How to split a long Go template function across multiple lines?

3 Answers3

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