[yaml] Expected block end YAML error

When pasting this YAML file into an online yaml parser, I got an expected block end error:

ADDATTEMPTING: 'Tentative d ajout '
ATTEMPTINGTOGIVE: 'Tenter de donner '
ATTEMPTINGTOSET1: 'Tentative de définition '
ATTEMPTINGTOSET2: ' avec '
ALREADYEXISTS: 'Erreur. Package existe déjà’
CANCEL1: 'Annulation...'
(...)

Error

ERROR:

while parsing a block mapping
  in "<unicode string>", line 1, column 1:
    ADDATTEMPTING: 'Tentative d ajout '
    ^
expected <block end>, but found '<scalar>'
  in "<unicode string>", line 6, column 11:
    CANCEL1: 'Annulation...'
              ^

With YAML, remember that it is all about the spaces used to define configuration through the hierarchical structures (indents). Many problems encountered whilst parsing YAML documents simply stems from extra spaces (or not enough spaces) before a key value somewhere in the given YAML file.

In my case, the error occured when I tried to pass a variable which was looking like a bytes-object (b"xxxx") but was actually a string.

You can convert the string to a real bytes object like this:

foo.strip('b"').replace("\\n", "\n").encode()

YAML follows indentation structure very strictly. Even one space/tab can cause above issue. In my case it was just once space at the start.

So make sure no extra spaces/tabs are introduced while updating YAML file

I would like to make this answer for meaningful, so the same kind of erroneous user can enjoy without feel any hassle.

Actually, i was getting the same error but for the different reason, in my case I didn't used any kind of quoted, still getting the same error like expected <block end>, but found BlockMappingStart.

I have solved it by fixing, the Alignment issue inside the same .yml file.

If we don't manage the proper 'tab-space(Keyboard key)' for maintaining successor or ancestor then we have to phase such kind of things.

Now i am doing well.

This error also occurs if you use four-space instead of two-space indentation.

e.g., the following would throw the error:

fields:
    - metadata: {}
        name: colName
        nullable: true

whereas changing indentation to two-spaces would fix it:

fields:
  - metadata: {}
    name: colName
    nullable: true