Fix quotation marks of tag values and escaping of field values

[Robert-Steiner]

Description

Fixes two issues related to quotation marks of tag values and improper escaping of field values.

1. Removed additional quotation marks for tag values with the type Float, SignedInteger and UnsignedInteger, otherwise they will be part of the string. (Removing the quotation marks for Text was already fixed in Fix improper quoting on tag values when the value was text #64.)

InfluxDB docs:

Do not double or single quote measurement names, tag keys, tag values, and field keys. It is valid line protocol but InfluxDB assumes that the quotes are part of the name.

2. Removed escaping of commas, equals and spaces for field values.

InfluxDB docs:

For string field values use a backslash character \ to escape:
double quotes "

Checklist

• Formatted code using cargo fmt --all
• Linted code using clippy cargo clippy --all-targets --all-features -- -D warnings
• Updated README.md using cargo readme -r influxdb -t ../README.tpl > README.md
• Reviewed the diff. Did you leave any print statements or unnecessary comments?
• Any unfinished work that warrants a separate issue captured in an issue with a TODO code comment

[Empty2k12]

Thanks for opening this PR 👍

Hopefully all issues regarding the line-protocol are resolved now!

If you notice any other problems feel free to open more issues or pull requests.

[mcronce]

@Empty2k12 this and #64 should actually fix a problem I was just debugging :) what are the chances you could push a new release to crates.io that includes these?

[Empty2k12]

@mcronce I'm looking to get #69 reviewed, and then release the crate on crates. Until then, you can reference the Git repo directly.

[mcronce]

@Empty2k12 So, this is fairly weird - I gave that a shot and got the following pair of errors (with a bonus warning) that, all together, are super confusing:

error[E0277]: the trait bound `influxdb::WriteQuery: influxdb::query::Query` is not satisfied
  --> src/main.rs:84:23
   |
84 |             match client.query(&query).await {
   |                                ^^^^^^ the trait `influxdb::query::Query` is not implemented for `influxdb::WriteQuery`

error[E0277]: the trait bound `influxdb::query::QueryTypes<'_>: From<&influxdb::WriteQuery>` is not satisfied
  --> src/main.rs:84:17
   |
84 |             match client.query(&query).await {
   |                          ^^^^^ the trait `From<&influxdb::WriteQuery>` is not implemented for `influxdb::query::QueryTypes<'_>`
   |
   = help: the following implementations were found:
             <influxdb::query::QueryTypes<'a> as From<&'a influxdb::query::read_query::ReadQuery>>
             <influxdb::query::QueryTypes<'a> as From<&'a influxdb::query::write_query::WriteQuery>>
   = note: required because of the requirements on the impl of `Into<influxdb::query::QueryTypes<'_>>` for `&influxdb::WriteQuery`

warning: unused import: `influxdb::Query`
  --> src/main.rs:19:5
   |
19 | use influxdb::Query;
   |     ^^^^^^^^^^^^^^^
   |
   = note: `#[warn(unused_imports)]` on by default

But it gets weirder. This doesn't happen when I specify version 0.1 from crates.io, but it does happen when I clone the repo, checkout the 0.1.0 tag, and build against that. I thought maybe I was hitting a compiler bug, but I tried updating stable and nightly to latest and got the same result.

This is probably just a fundamental language misunderstanding on my part, but what are the chances you have a recommendation? Also, if it's easier/preferable, I can file a separate issue.

In any case, the code in question:

// queries is a Vec<WriteQuery>
for query in queries.into_iter() {
        match client.query(&query).await {
                Ok(_) => (),
                Err(e) => println!("Query for character {} fail: {:?}", id, e)
        };
}