Summary:
We store the relational view in `view.json.gz` instead of `view.json`,
taking advantage of the isomorphic `pako` library for gzip encoding and
decoding.
Sample space savings (note that post bodies are included; i.e., #747 has
not been applied):
SAVE OLD (B) NEW (B) REPO
89.7% 25326 2617 sourcecred/example-github
82.9% 3257576 555948 sourcecred/sourcecred
85.2% 11287621 1665884 ipfs/js-ipfs
88.0% 20953425 2520358 gitcoinco/web
84.4% 38196825 5951459 ipfs/go-ipfs
84.9% 205770642 31101452 tensorflow/tensorflow
<details>
<summary>Script to generate space savings output</summary>
```shell
savings() {
printf '% 7s % 11s % 11s %s\n' 'SAVE' 'OLD (B)' 'NEW (B)' 'REPO'
for repo; do
file="${SOURCECRED_DIRECTORY}/data/${repo}/github/view.json.gz"
if ! [ -f "${file}" ]; then
printf >&2 'warn: no such file %s\n' "${file}"
continue
fi
script="$(sed -e 's/^ *//' <<EOF
repo = '${repo}'
pre_size = $(<"${file}" gzip -dc | wc -c)
post_size = $(<"${file}" wc -c)
percentage = '%0.1f%%' % (100 * (1 - post_size / pre_size))
p = '% 7s % 11d % 11d %s' % (percentage, pre_size, post_size, repo)
print(p)
EOF
)"
python3 -c "${script}"
done
}
```
</details>
Closes#750.
Test Plan:
Comparing the raw old version with the decompressed new version shows
that they are identical:
```
$ <~/tmp/sourcecred/data/sourcecred/example-github/github/view.json \
> shasum -a 256 -
63853b9d3f918274aafacf5198787e18185a61b9c95faf640a1e61f5d11fa19f -
$ <~/tmp/sourcecred/data/sourcecred/example-github/github/view.json.gz \
> gzip -dc | shasum -a 256
63853b9d3f918274aafacf5198787e18185a61b9c95faf640a1e61f5d11fa19f -
```
Additionally, `yarn test --full` passes, and `yarn start` still loads
data and runs PageRank properly.
wchargin-branch: gzip-relational-view
7f81337d74